Capitulum naked, thick-walled, globular, supported by stout peduncle; filamentary appendage at base of cirrus I; caudal appendage multi-segmented; cirri ctenopod or acanthopod, rarely lasiopod.

Heteralepas Pilsbry, 1907a.

The family consists of two genera: Heteralepas Pilsbry, 1907a and Paralepas Pilsbry, 1907a.

Filamentary appendage present at base of cirrus I, short; posterior rami of cirri V and VI shorter and more slender than anterior rami.

Alepas rex Pilsbry, 1907c: 186, fig. 3, pl. IV fig. 7; type locality: Kauai Island, Hawaiian waters.

Tanimbar Island: 1 specimen, MNHN-IU-2019-4877, stn. CP 46, 08°01'S, 132°51'E, 271–273 m depth, 29 October 1991.

Capitulum rounded, plates absent; wall of capitulum thick; orifice crenulated with no more than two crests on carinal region; cirrus VI with caudal appendage; maxillule strongly notched.

Capitulum and peduncle yellowish. Orifice slightly protuberant, crenulated, occupying one half to one third capitular length, parallel to or at oblique angle to capitulum; integument thick, chitinous. Cirrus I with anterior rami (20-segmented) shorter than posterior rami (25-segmented); cirrus VI with long caudal appendage, 24-segmented, 2/3 length of anterior ramus. Mandibles with four large teeth excluding inferior angle; maxillule strongly notched, two large setae at upper angle, blade-shaped setae on cutting margin; labrum concave with numerous teeth. Measurements of specimen: height of capitulum 18.50 mm, width 12.82 mm, thickness 5.97 mm; length of peduncle 15.26 mm, width 5.55 mm.

Singapore; Indo-west Pacific: Indian Ocean; Australia; Malay Archipelago; Vietnam; Condor Island; South China Sea; East China Sea; Taiwan, Philippines; South Japan; NE New Zealand; fouling hard rock substrata, crabs, gorgonians, antipatharians, deep-sea cables; 48–500 m depth (Jones and Hosie 2016). Recently, the species has also been recorded from the Lifamatola Sea and the Halmahera Sea, Indonesia (Pitriana et al. 2020). In this study, Heteralepas japonica was found at Tanimbar Island, Indonesia.

Hirado Strait, Japan, 146 m depth (Aurivillius 1892).

Figure 1. 

Heteralepas japonica (Aurivillius, 1892) (MNHN-IU-2019-4877). a. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. anterior view, orifice; d. posterior view, capitulum and peduncle. Scale bar: 6 mm (a–d).

Maxillule slightly notched; filamentary appendages well-developed; posterior and anterior rami of cirri V and VI similar in length; segments of cirri V and VI square-shaped, each armed with semi-circular brush of many setae on anterior face.

Alepas percarinata Pilsbry, 1907c: 185, fig. 2, pl. IV, fig. 8; type locality: Molokai, Hawaiian waters.

– Kei Islands: 6 specimens, MNHN-IU-2019-4882, Stn. CP 25, 05°30'S, 132°52'E, 336–346 m depth, 26 October 1991, attached to dead stem of gorgonian.

– Tanimbar Island: 4 specimens, MNHN-IU-2019-4883, Stn. CP 85, 09°22'S, 131°14'E, 240–245 m depth, 4 November 1991, attached to spine of sea urchin.

Capitulum yellowish with globular shape; anterior and posterior rami of cirrus V and VI similar in length.

Capitulum yellowish, globose, small-sized, externally smooth; orifice crenulated; peduncle rather short. Segments of rami of cirrus I wide, anterior ramus (9-segmented) shorter than posterior ramus (13-segmented); cirrus VI with short caudal appendage, 8-segmented. Penis annulated, setae sparsely distributed over most of surface, a few longer setae towards tip. Maxillule notched, two large and one small setae at upper angle; mandible with four major teeth; labrum concave, with numerous teeth. Measurements of specimen: height of capitulum 8.34 mm, width 6.67 mm, thickness 4.53 mm; length of peduncle 3.84 mm, width 2.60 mm.

Java Sea (Indonesia); Mediterranean Sea; West Africa; Indo-west Pacific: Indian Ocean; Australia; Malay Archipelago; Taiwan; Japan; Philippines; Northern New Zealand; 485–736 m depth; attached to spines of cidarids (Jones and Hosie 2016). In this study, Paralepas minuta was found at Kei Islands and Tanimbar Island, Indonesia.

Mediterranean Sea (Chan et al. 2009b).

Paralepas minuta (Philippi, 1836) can be distinguished from Paralepas ovalis (Hoek, 1907) by the presence of triangular scutal areas and from Paralepas nodulosa Broch, 1922 by the absence of “well defined, scanty, almost thorn-like warts” (Broch 1922).

Figure 2. 

Paralepas minuta (Philippi, 1836) (MNHN-IU-2019-4882). а. left lateral view, capitulum and peduncle; b. right lateral view, capitulum and peduncle; c. anterior view, orifice. Scale bar: 5 mm (a–c).

– Tanimbar Island: 45 specimens, MNHN-IU-2019-4878, Stn. CP 54, 08°21'S, 131°43'E, 836–869 m depth, 30 October 1991, attached to spine of sea urchin.

Capitulum globular with numerous tubercles on surface, scuta absent, orifice small, not protuberant, peduncular length more than half capitular length.

Capitulum and peduncle yellowish. Capitulum globular with thick, chitinous, large warts all over surface. Peduncle rather long, narrower than capitulum; surface bearing tubercles, smaller than those of capitulum. Cirrus I placed rather far from cirrus II; cirri II–VI similar, length and number of segments slightly increasing from second to sixth; cirrus VI with 7-segmented caudal appendage. Penis indistinctly segmented, few long hairs towards tip. Maxillule notched, two large setae on upper notch; mandibles with three major teeth, inferior angle considered as fourth tooth; labrum with continuous row of numerous short, strong, blunt teeth. Measurements of specimen: height of capitulum 5.14 mm, width 3.69 mm, thickness 1.81 mm; length of peduncle 5.08 mm, width 1.31 mm.

Flores Sea (Indonesia); Philippines; Bass Strait, N of Tasmania; attached to spines of echinoids, for example, Histocidaris elegans (Agassiz, 1879); 182–538 m depth (Jones and Hosie 2016). In this study, Paralepas morula was found at Tanimbar Island, Indonesia.

Bali Sea, North of Lombok; 538 m depth (Hoek 1907).

Most of the smaller specimens do not show the warts that are characteristic of this species.

Figure 3. 

Paralepas morula (Hoek, 1907) (MNHN-IU-2019-4878). а. left lateral view, capitulum and peduncle; b. right lateral view, capitulum and peduncle. Scale bar: 3 mm (a, b).

Capitulum with up to five plates, including tergum and scutum; scutum in some species split into two (resulting in seven plates); some or all plates may be degenerate or absent; umbos of terga apical, those of carina and scuta fundamentally basal; peduncle without calcareous scales; maxillule not stepped; cirrus I widely separated and much shorter than posterior cirri; caudal appendages uniarticulate, spinose.

Poecilasma Darwin, 1852: 99.

Capitulum with five plates, approximate or variously reduced; scutum divided into two parts; apex of carina extending to, or slightly overlapping basal end of terga, basally terminating in disc.

Poecilasma fissa Darwin, 1852: 109, pl. II, fig. 4, pl. X, fig. 29.

– Tanimbar Island: 2 specimens, MNHN-IU-2019-4861, Stn. CP 79, 09°16'S, 131°22'E, 239–250 m depth, 3 November 1991, attached to crab leg.

Capitulum broadly oval, with five smooth plates; carina not extending to area between terga; peduncle with circles of small protuberances; cirri short.

Capitulum yellowish, with five tranparent, smooth plates. Scutum bilobed, occludent segment narrow, bow-shaped; tergum sub-triangular, nearly half as broad as long. Carina very narrow, slightly curved downwards, end blunt. Peduncle yellow, plainly ringed, spines absent. Cirrus I with anterior ramus wider than posterior ramus. Maxillule notched, with two strong teeth in upper part; mandible with four teeth, fourth pectinated, placed very close to inferior angle; labrum with row of minute teeth. Measurements of specimen: basal diameter of capitulum 0.94 mm; capitular height 7.03 mm; total height 10.40 mm; scutal width 4.11 mm; scutal length 5.85 mm; tergal width 1.00 mm; tergal length 3.13 mm.

Indo-west Pacific: Indian Ocean; Madagascar through Malaysia, Hong Kong, South China Sea; Taiwan; Philippines; South Japan; tropical West and central Pacific Ocean to Fiji and Hawaii; attached to decapod crustaceans; shallow water (Jones and Hosie 2016). In this study, Dianajonesia amygdalum was found at Tanimbar Island, Indonesia.

Nordwachter Island, Thousand Islands, Java Sea (Aurivillius 1894).

Figure 4. 

Dianajonesia amygdalum (Aurivillius, 1894) (MNHN-IU-2019-4861). а. left lateral view, capitulum and peduncle; b. right lateral view, capitulum and peduncle; c. anterior view, orifice; d. posterior view, carina. Scale bar: 2 mm (a–d).

– Tanimbar Island: 3 specimens, MNHN-IU-2019-4859, Stn. CP 78, 09°06'S, 131°24'E, 284–295 m depth, 3 November 1991.

Capitulum with scutum divided into two segments parallel to occludent margin; tergum with excavation in scutal margin near occludent margin, receiving tip of occludent segment of scutum.

Capitulum oval, apex pointed, slightly thick, swollen. Scutum with larger segment strongly bowed, basal margin short, apex pointed; smaller segment bowed, terminating in point at base, tergal margin rounded, fitting exactly into excavation of tergum. Tergum triangular, characteristic excavation at scutal margin near occludent margin. Carina narrow, terminating in spatula-shaped disc. Cirrus I with anterior and posterior rami subequal (each five-segmented); cirri II–VI longer, more slender; cirrus VI with caudal appendages. Penis thick, ringed, especially mid-length, terminating in narrower, curved part. Maxillule notched, two large teeth on upper side; mandible with four teeth, largedistance between first and second teeth. Labrum convex, with numerous blunt teeth. Measurements of specimen: basal diameter of capitulum 1.06 mm; capitular height 7.12 mm; total height 12.69 mm; scutal width 3.08 mm; scutal length 6.09 mm; tergal width 1.30 mm; tergal length 3.47 mm.

Indo-west Pacific: East coast of Africa (Zanzibar); Gulf of Aden; Indonesia; Malay Archipelago; South China Sea; East China Sea; Philippines; South Japan (Goto Island); attached to echinoid spines, crustaceans; palinurids and cirripedes; 189–600 m depth (Jones and Hosie 2016). In this study, Dianajonesia excavatum was found at Tanimbar Island, Indonesia.

Siboga station 253; 5°48.2'S, 132°15'E; depth: 304 m; bottom: grey clay, hard and crumbly (Hoek 1907).

Figure 5. 

Dianajonesia excavatum (Hoek, 1907) (MNHN-IU-2019-4859). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. anterior view, orifice; d. posterior view, carina. Scale bar: 2 mm (a–d).

Capitulum with five plates; scutum with two distinct segments, united at rostral angle; carina generally extending up between terga, terminating downwards as imbedded disc (fork- or cup-shaped).

Octolasmis warwicki Gray, 1825: 100. – 1830: pl. VI, fig. 16.

– Kei Islands: 4 specimens, MNHN-IU-2019-4864, Stn. CP 27, 05°33'S, 132°51'E, 314–304 m depth, 27 October 1991.

– Tanimbar Island: 6 specimens, MNHN-IU-2019-4862, Stn. DW 24, 05°32'S, 132°51'E, 230–243 m depth, 26 October 1991.

Capitulum flattened; five plates, separated by thin membrane; scutum consisting of two distinct segments, with point of junction perfectly calcified; base of carina oval.

Capitulum and peduncle yellowish. Scutum with basal segment narrow, L-shaped; tergum triangular, three prominent ridges at scutal margin; base of carina crescent-formed cup. Cirrus I with anterior ramus (6-segmented) shorter than posterior ramus (8-segmented); cirrus VI with small caudal appendage. Maxillule notched, three large setae on upper notch; mandible with four teeth, inferior angle produced into single strong spine; labrum concave, with numerous teeth. Measurements of specimen: basal diameter of capitulum 1.89 mm; capitular height 8.69 mm; total height 10.47 mm; scutal width 3.5 mm; scutal length 7.16 mm; tergal width 0.80 mm; tergal length 6.53 mm.

Indo-west Pacific: East and South African Coast, Indian Ocean, Australia, Indonesia, Malay Archipelago, Vietnam, South China Sea, East China Sea, Philippines, Taiwan, South Japan; attached to hydroid, gorgonians, antipatharians, sea urchin spines, nylon cord, sometimes fouling; 14–818 m depth (Jones and Hosie 2016). In this study, Dichelaspis orthogonia was found at Kei Islands and Tanimbar Island, Indonesia.

Unknown.

The type locality of this species is unknown. The species was re-discovered in the Malay Archipelago by the Siboga Expedition in 40–112 m depth (Hoek 1907) and the Albatross Expedition, off Kagoshima Gulf, Japan, in 87 m depth (Pilsbry 1907d).

Figure 6. 

Dichelaspis orthogonia Darwin, 1852 (MNHN-IU-2019-4864). а. left lateral view capitulum and peduncle; b. right lateral view, capitulum and peduncle. Scale bar: 2 mm (a–b).

Capitulum with five approximate, fully calcified plates; scutum quadrangular, umbone subcentral; carina becoming larger towards base; peduncle short.

Megalasma (Glyptelasma) subcarinatum Pilsbry, 1907a: 91, pl. VII, figs 1–5; type locality: Atlantic Ocean, East of New Jersey, USA.

– Tanimbar Island: 14 specimens, MNHN-IU-2019-4873, Stn. CP 54, 08°21'S, 131°43'E, 836–869 m depth, 30 October 1991, attached to spine of sea urchin; 1 specimen, MNHN-IU-2019-4875, Stn. CC 57, 08°19'S, 31°53'E, 603–620 m depth, 31 October 1991; 3 specimens (1 adult, 2 juveniles), MNHN-IU-2019-4876, Stn. CP 73, 08°29'S, 131°33'E, 840–855 m depth, 2 November 1991, attached to spines of sea urchins.

Capitulum with five plates; carina enlarged, keel-shaped; tergum with basal point truncated; maxillule notched; caudal appendages with relatively-long spines at tip.

Capitulum whitish, peduncle brownish. Capitulum compressed, striated, about twice as long as broad. Scutum with apex pointed; tergum basally truncated, flat, oblong. Carina flat, very narrow, enlarged, keel-shaped in basal region. Cirrus I with anterior and posterior rami equal length; cirrus II–VI long, slender; cirrus VI with small caudal appendages. Penis with few long hairs towards tip. Maxillule notched, with strong teeth on upper side; mandible with four teeth; labrum with row of small teeth on crest. Measurements of specimen: basal diameter of capitulum 1.45 mm; capitular height 10.44 mm; total height 13.99 mm; scutal width 4.79 mm; scutal length 9.01 mm; tergal width 1.87 mm; tergal length 5.07 mm.

West-southwest Pacific: from Australia (Sydney) to Indonesia (Sumbawa) and the Philippines (northwest Panay Island); East Indian Ocean; attached to glassy spicule of hexactinellid sponge, fragments of sea urchin tests, spines of cidarids; 395–935 m depth (Jones and Hosie 2016). In this study, Glyptelasma gracile was found at Tanimbar Island, Indonesia.

Challenger expedition Station 164a (off Sydney, Australia); 34°13'S, 151°38'E; depth 125 m; bottom: grey ooze (Hoek 1883).

Figure 7. 

Glyptelasma gracile (Hoek, 1883) (MNHN-IU-2019-4875). а. left lateral view, capitulum and peduncle; b. right lateral view, capitulum and peduncle; c. anterior view, orifice; d. posterior view, carina. Scale bar: 2 mm (a–d).

Capitulum with five strong, calcified plates; scutal umbones subcentral; apex of carina sometimes slightly overlapping basal end of terga, progressively becoming broader towards base; peduncle very short.

Megalasma striatum Hoek, 1883: 51, pl. II, figs 5–9, pl. VII, figs 8, 9.

– Kei Islands: 1 specimen, MNHN-IU-2019-4868, Stn. CP 09, 05°23'S, 132°29'E, 368–389 m depth, 23 October 1991; 1 specimen, MNHN-IU-2019-4869, Stn. CP 16, 05°17'S, 132°50'E, 315–349 m depth, 24 October 1991, attached to sea urchin spine; 2 specimens, MNHN-IU-2019-4866, Stn. CP 17, 05°15'S, 133°01'E, 439–459 m depth, 24 October 1991.

– Tanimbar Island: 1 specimen, MNHN-IU-2019-4867, Stn. CP 46, 08°01'S, 132°51'E, 271–273 m depth, 29 October 1991; 4 specimens (3 attached to sea urchin spine), MNHN-IU-209-4870, Stn. DW 49, 08°00'S, 132°59'E, 206–210 m depth, 29 October 1991; 6 specimens, MNHN-IU-2019-4871, Stn. CP 85, 09°22'S, 131°14'E, 240–245 m depth, 4 November 1991, attached to spines of sea urchin.

Capitulum ovate, occludent margin almost same length as carinal margin; capitular plates heavily calcified, markedly sculptured with radial striations between grooves of growth lines; peduncle short, covered by capitulum.

Capitulum white, with five calcified plates, surfaces strongly striated. Scutum with basal margin rotated; tergum triangular in lateral view; carina with dorsal roof widening apically on either side of midline groove. Cirrus I with anterior ramus wider than posterior ramus. Maxillule with three strong setae at upper angle separated by wide notch; mandible with four teeth, lower angle sharp. Measurements of specimen: basal diameter of capitulum 2.14 mm; capitular height 9.36 mm; total height 9.36 mm; scutal width 3.81 mm; scutal length 7.28 mm; tergal width 1.58 mm; tergal length 4.29 mm.

West-southwest Pacific, Indo-west Pacific, East coast of Africa, Indian Ocean, north Australia, Indonesia, Malay Archipelago, East China Sea, South China Sea, Taiwan, Philippines, south Japan to New Zealand; attached to echinoid spines, antipatharians, gorgonians, glassy spicule of hexactinellid sponges, corallines; 125–984 m depth (Jones and Hosie 2016). In this study, Megalasma striatum was found at Kei Islands and Tanimbar Island, Indonesia.

Philippine Archipelago (Hoek 1883).

Figure 8. 

Megalasma striatum Hoek, 1883 (MNHN-IU-2019-4868). а. left lateral view, capitulum; b. right lateral, capitulum; c. anterior view, capitulum and peduncle; d. posterior view, carina. Scale bar: 2 mm (a–d).

Capitulum with fully or partially calcified plates; peducle with calcareous or phosphorus scales. According to Gale (2016), the Scalpellidae have a maximum of 14 plates i.e. carina, rostrum, paired scuta, terga, upper latera, carinolatera, rostrolatera and inferior median latera; and rarely 13 plates, due to secondary loss of the rostrum.

Formerly, the subfamily was characterised by a subapical carinal umbo, inflexed carina and subapical umbones of the upper and inframedian latus (Zevina 1978a). Gale (2016) characterised the subfamily by the broad, low, straplike and gently incurved rostrolatus. The rostrum is broader than high, rectangular, trapezoidal or triangular and its large, triangular, lateral surfaces contact the interior of the rostrolatus. The articulation surface between the rostrum and rostrolatus extends over the entire height of both plates.

Scalpellum Leach, 1817: 68.

Scalpellines without specialised contact between carina and carinolatus, merely a cresentic concavity on interior of plate that forms a rim slightly overlapping the upper latus; umbo of carinolatus upright, only slightly incurved, dorsal margin gently convex; inframedian surface of carinolatus well demarcated, slightly inset.

– Kei Islands: 2 specimens, MNHN-IU-2019-4925, Stn. CP 09, 05°23'S, 132°29'E, 368–389 m depth, 23 October 1991; 1 specimen, MNHN-IU-2019-4926, Stn. CP 16, 05°17'S, 132°50'E, 330–350 m depth, 24 October 1991, attached to gorgonian.

Capitulum with 14 plates, smooth, white and reddish coloured; carina simply, strongly bowed, roof slightly convex with umbo at apex; rostrum triangular, distinct; upper latus quadrangular, large; infra-median latus triangular.

Capitulum flat, rather broad, not covered by distinct membrane. Scutum with occludent margin arched, forming with tergal margin a triangular portion projecting over tergum. Tergum surpassing scutal area with occludent margin almost straight. Upper latus quadrangular, angle at apex between scutal and tergal margins distinctly projecting over scutum. Rostrum small, triangular; rostrolatus very low, quadrangular; infra-median latus small, triangular, umbo at apex; carinal latus larger than other latera with carinal margin arched. Cirrus I with anterior and posterior rami almost same length; cirrus VI with long caudal appendages. Maxillule not notched, with large spine on upper side, cutting edge almost straight; mandible with three large teeth excluding inferior angle. Measurements of two specimens: height of capitulum 12.51–20.57 mm, width 7.39–10.55 mm, thickness 4.09–6.51 mm; length of peduncle 5.10–7.76 mm, width 4.36–6.62 mm.

Java Sea, Indonesia. Pacific: western central and northwest; Philippines; Kagoshima Sea and Sagami Bay, Japan; 133–551 m depth (Shalaeva and Boxshall 2014). In this study, Diotascalpellum rubrum was found at Kei Islands, Indonesia.

Philippines, 12°43'N, 122°10'E; depth, 180 m and 207 m; bottom, mud (near Luzon) (Hoek 1883).

Figure 9. 

Diotascalpellum rubrum (Hoek, 1883) (MNHN-IU-2019-4925). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. rostral view showing the capitulum and peduncle; d. carinal view. Scale bar: 5 mm (a–d).

Concave scalpellines; internal surface upper latus covered by epidermis, short carinal margin present on carinolatus; carinolatus with incurved umbones, lateral margin strongly convex.

Scalpellum regium Thomson, 1873; type locality: Stn 61: Atlantic, Western Central (North Western Atlantic Basin); 5,210 m depth.

– Tanimbar Island: 3 specimens, MNHN-IU-2019-4909, Stn. CP 38, 07°40'S, 132°27'E, 620–666 m depth, 28 October 1991; 1 specimen, MNHN-IU-2019-4910, Stn. DW 49, 08°00'S, 132°59'E, 206–210 m depth, 29 October 1991; 1 specimen, MNHN-IU-2019–4911, Stn. CC 57, 08°19'S, 131°53'E, 603–620 m depth, 31 October 1991; 1 specimen, MNHN-IU-2019-4912, Stn. CP 52, 08°03'S, 131°48'E, 1244–1266 m depth, 30 October 1991.

Capitulum with 14 plates, surface covered by chitinous, almost smooth membrane; carina simply, not strongly bowed, apex projecting freely, roof not flat; umbo of the carina apical; upper latus almost triangular.

Capitulum inflated, subtriangular, apices of plates projecting freely through membrane, growth lines fairly distinct. Scutum trapezioid, umbo apical. Tergum large, oval, truncated, very pointed, extending between upper latus and carina. Carina simply, slightly bowed, roof slightly convex, apex projecting freely. Upper latus quadrangular; rostrum very small, carinate; rostral latus trapeziform; infra-median latus triangular, moderately small; carinal margins of carinal latera convex, touching each other at base and below middle of carina. Peduncle stout, slightly thinner below apex. Cirrus I unequal, anterior ramus oval, posterior ramus more slender; cirrus VI with long caudal appendages. Maxillule not notched, large spine on upper side, cutting edge almost straight; mandible with three large teeth excluding inferior angle. Measurements of five specimens: height of capitulum 7.88–14.89 mm, width 4.81–10.65 mm, thickness 2.15–5.24 mm; length of peduncle 3.38–9.13 mm, width 2.09–6.04 mm.

Pacific, Central and Southwest; Tasman Sea, north-eastern Australia; 788–2,745 m depth (Jones 2012; Shalaeva and Boxshall 2014). In this study, Regioscalpellum moluccanum was found at Tanimbar Island, Indonesia.

Banda Sea (4°21'S, 129°7'E); Challenger stn 195; 2,606 m depth: bottom temp. 3 °C; substrate grey ooze (Hoek 1883).

Figure 10. 

Regioscalpellum moluccanum (Hoek, 1883) (MNHN-IU-2019-4909). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. carinal view showing the capitulum and peduncle; d. rostral view showing the capitulum and peduncle. Scale bar: 4 mm (a–d).

Scalpellines with carinal and scutal umbones subapical; carinolatus with horn-like projection, often recurved, extending beyond carinal margin; inframedian latus rectangular to slightly trapezoidal, with low umbo; upper latus rhomboidal with subapical umbo; rostrum rectangular, pyramidal, with large sub-umbonal surface.

Lepas scalpellum Linnaeus, 1767: 1109.

Unknown.

– Tanimbar Island: 1 specimen, MNHN-UI-2019-4929, Stn. DW 49, 08°00'S, 132°59'E, 206–210 m depth, 29 October 1991.

Capitulum with 14 fully calcified plates; tergum triangular; inframedian latus broad, quadrilateral with umbo near to basal; upper latus rhomboidal, umbo sub-apical; carinal lateral horn-shaped, with angle extending beyond carina.

Capitulum subtriangular, covered by membrane. Tergum triangular, occludent and basal margins slightly convex; scutum quadrangular, basal and upper latus margins concave; upper latus pentagonal; rostrolatus quadrangular; inframedian latus broad, rectangular, umbo close to basal margin; carinolatus horn-shaped with slightly deep transverse furrows, umbo at basi-carinal angle; carina convex, umbo apical. Cirrus I with rami unequal, anterior ramus broader than posterior ramus; both rami densely covered with long setae. Maxilla subtriangular, with dense long setae; maxillule notched, with numerous setae; mandible with three teeth, inferior angle with large cuspidate setae. Measurements of specimen: height of capitulum 15.90 mm, width 10.29 mm, thickness 4.58 mm; length of peduncle 6.97 mm, width 5.67 mm.

In this study, Scalpellum sp. was found in Tanimbar Island, Indonesia.

Figure 11. 

Scalpellum sp. (MNHN-UI-2019-4929). а. left lateral view, capitulum and peduncle; b. right lateral view, capitulum and peduncle; c. rostral view, capitulum and peduncle; d. carinal view. Scale bar: 7 mm (a–d).

– Tanimbar Island: 1 specimen, MNHN-IU-2019-4888, Stn. CP 71, 08°38'S, 131°44'E, 477–480 m depth, 2 November 1991; 1 specimen, MNHN-IU-2019-4889, Stn. CC 58, 08°19'S, 132°02'E, 457–461 m depth, 31 October 1991; 6 specimens, MNHN-IU-2019–4890, Stn. CC 42, 07°53'S, 132°42'E, 350–354 m depth, 28 October 1991; 3 specimens, MNHN-IU-2019-4891, Stn. CP 69, 08°42'S, 131°53'E, 356–368 m depth, 2 November 1991; 5 specimens, MNHN-IU-2019-4892, Stn. CC 41, 07°45'S, 132°42'E, 393–401 m depth, 28 October 1991; 5 specimens, MNHN-IU-2019-4893, Stn. CP 59, 08°20'S, 132°11'E, 399–405 m depth, 31 October 1991, 2 specimens attached to glass rope sponge.

– Kei Islands: 8 specimens, MNHN-IU-2019-4894, Stn. CP 06, 05°49'S, 132°21'E, 287–298 m depth, 22 October 1991.

Capitulum rhomboidal, compressed; carina strongly angled at umbo; scutum large, umbo at tergo-occludent angle; tergum triangular; inframedian latus pentagonal; carinolateral horn-shaped.

Capitulum with 14 fully calcified plates. Scutum large, longer than broad, apex slightly projecting over tergum; tergum large, triangular, apex erect, slightly recurved. Carina distinctly bent near middle, umbo distant from apex. Cirrus I with anterior ramus oval (12-segments), posterior ramus slender, long (15-segments); cirri II–VI slender, long, rami almost equal length; cirrus VI with short caudal appendages (six segments). Maxillule not notched, with numerous setae; mandible with six teeth excluding inferior angle. Measurements of five specimens: height of capitulum 31.69–52.00 mm, width 28.20–40.11 mm, thickness 11.19–18.56 mm; peduncle length 28.29–86.59 mm, width 11.39–17.94 mm.

Indo-west Pacific: Indian Ocean, off Nicobar Island; Indonesia: Java Sea, Bali Straits; north west & north east Australia; Malay Archipelago; Celebes; Sulu Arch.; Sulu Sea; South China Sea; East China Sea; Philippines; Taiwan; east coast of south Japan, Sagami Bay, off Hondo; attached to mollusc shells, anchor filaments of hexactinellid sponges, telegraph cables, carapaces of crabs, stones; 146–2117 m depth (Jones and Hosie 2016). In this study, Scalpellum stearnsi was found at Tanimbar Island and Kei Islands, Indonesia.

East coast of Japan, between the Bay of Tokyo and the Inland Sea (Jones 1992).

For the first time, Scalpellum stearnsi was found in Japan and described by Pilsbry (1890). During the Siboga expedition (1899), S. stearnsi was collected from different locations in the Malay Archipelago with the depths varying from 204 m to 450 m. Hoek (1907) found intraspecific variations of the shell plate morphology. He then divided S. stearnsi into two groups, i.e. variety robusta and var. gemina, which differed in the shape of the tergum. The species S. stearnsi in this study belongs to the group of var. gemina because of the V-shaped tergum.

Scalpellum stearnsi has a low period of larval development (Ozaki et al. 2008) and a slow growth rate (Yusa et al. 2018). This can result in the broad geographical distribution of this species. Recently, Lin et al. (2020) examined the diversity and genetic differentiation of populations of S. stearnsi from the East China Sea, West Philippine Basin, Sulu Sea and Caroline Trenches, which resulted in four distinct clades of S. stearnsi.

Figure 12. 

Scalpellum stearnsi Pilsbry, 1890 (MNHN-IU-2019-4888). а. left lateral view, capitulum and peduncle; b. right lateral view, capitulum and peduncle; c. rostral view, capitulum and peduncle; d. carinal view. Scale bar: 14 mm (a–d).

Capitulum with 14 or 13 plates, reduced in differing stages or proportions; carina with two umbo positions; females considered rarer than hermaphrodites; males saclike, usually without plates, rarely with two or four reduced plates.

Meroscalpellum Zevina, 1978b: 1346.

Plates strongly reduced; partly obscured under heavy cuticle; tergum double branched, depressed at base; scutum triangular; upper lateral triangular; midlateral very small, umbo apical; caudal appendages very long; hermaphrodites.

Scalpellum alcockianum Annandale, 1905: 82; type locality: Gulf of Manaar and Andaman Sea.

– Tanimbar Island: 2 specimens, MNHN-IU-2019-4903, Stn. CP 71, 08°38'S, 131°44'E, 477–480 m depth, 2 November 1991; 5 specimens, MNHN-IU-2019-4904, Stn. CC 21, 05°14'S, 133°00'E, 688–694 m depth, 25 October 1991 attached to glass rope sponge; 1 specimen, MNHN-IU-2019-4905, Stn. CC 40, 07°46'S, 132°31'E, 443–468 m depth, 28 October 1991; 5 specimens, MNHN-IU-2019-4906, Stn. CC 57, 08°19'S, 131°53'E, 603–620 m depth, 31 October 1991.

Capitulum with plates buried or obscure; plates reduced in size; tegum reduced, forming four-pointed star; scutum small; peduncle armed with distinct circles of large, calcareous scales.

Capitulum brownish, large, ovoid, inflated, with 13 capitular plates, including a vestigial rostrum, plates embedded and mostly concealed by thick, opaque membrane. Scutum small, widely separated from all remaining plates except tergum, margins not excavated or deeply concave; tergum reduced in form as four-pointed star, with two rays greatly and two rays slightly produced. Carina reduced in size, apex approaching terga, widely separated from remaining plates. Peduncle cylindrical, similar length to capitulum, with large calcareous scales arranged in alternating rows. Cirrus I with anterior ramus oval (8-segments), posterior ramus slender, long (12-segments); cirri II–VI slender, long, rami almost equal length; cirrus VI with caudal appendages; caudal appendages 1/3 length of cirrus VI, 15-segmented, tapering distally. Penis rather short, smooth, pointed. Maxilla bilobed, dense setae on margin. Maxillule relatively large, with broad, shallow excavation on lower margin occupying more than half margin, remainder of margin obliquely subtruncate; mandible with three main teeth in addition to inner angle, which is variously divided, broad as a whole. Measurements of five specimens: height of capitulum 17.71–35.06 mm, width 12.91–28.06 mm, thickness 4.96–18.20 mm; length of peduncle 13.42–28.67 mm, width 6.66–10.79 mm.

Indonesian Seas, eastern Australia, New Zealand; 109–915 m depth (Jones 1992). In this study, Alcockianum persona was found at Tanimbar Island, Indonesia.

Type лocality. Timor Sea (10°22'30"S, 120°7'30"E); 109–366 m depth: bottom temp. 13.1 °C (Jones 1992).

Figure 13. 

Alcockianum persona (Annandale, 1916) (MNHN-IU-2019-4903). а. left lateral view, capitulum and peduncle; b. right lateral view, capitulum and peduncle; c. rostral view, capitulum and peduncle; d. carinal view. Scale bar: 9 mm (a–d).

Capitulum of female with 14 partially calcified plates; tergum in shape of inverted V; scutum with moderately long apicolateral arm, 1/4 to 1/2 length of tergal margin; basal margin of scutum entire; upper latus pentagonal to triangular or subrectangular, with or without short depending arm; carinolatus as high as or slightly higher than wide, umbo at basicarinal angle; inframedian latus higher than wide, vase-shaped, umbo submedial to basal; rostrolatus wider than high, commonly less than twice height of inframedian latus; caudal appendage relatively long.

Scalpellum subflavum Annandale, 1906.

– Tanimbar Island: 4 specimens, MNHN-IU-2019-4932, Stn. CP 53, 08°18'S, 131°41'E, 1026–1053 m depth, 30 October 1991.

Capitulum with 14 partly calcified plates; carina with flat roof; apex of tergum curved towards carina; rostral latus trapezoidal in shape; peduncle short.

Capitulum yellowish, with 14 plates separated by broad, chitinous spaces. Peduncle short, curved, scales large, not numerous. Scutum long, narrow; umbo apical, divided into two segments, occludent segment large, increasing in width from upper to lower part, other segment very narrow. Tergum divided into occludent and carinal segments, with triangular, chitinous portion between, umbo apical, distinctly recurved. Cirrus I unequal, anterior ramus oval, posterior ramus slender long; cirrus VI with caudal appendages. Maxillule slightly notched, two long and one short setae on upper side; mandible with three teeth excluding inferior angle; labrum cutting edge straight, very fine teeth on cutting edge. Measurements of the four specimens: height of capitulum 9.56–12.73 mm, width 4.67–7.13 mm, thickness 1.85–3.21 mm; length of peduncle 3.37–4.77 mm, width 1.83–3.27 mm.

Eastern Indian Ocean; Northwest and Western Central Pacific; Malay Archipelago; Japan; Taiwan; Indonesia; attached to shell of gastropod, gorgonians, rocks; 805–6,810 m depth (Jones and Hosie 2016). In this study, Annandaleum japonicum was found at Tanimbar Island, Indonesia.

Pacific, Northwest (off Nagoya, south of Japan); 1,017 m depth (Shalaeva and Boxshall 2014).

Figure 14. 

Annandaleum japonicum (Hoek, 1883) (MNHN-UI-2019-4932). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. rostral view showing the capitulum and peduncle; d. carinal view. Scale bar: 2 mm (a–d).

– Tanimbar Island: 1 specimen, MNHN-IU-2019-4931, Stn. CP 54, 08°21'S, 131°43'E, 836–869 m depth, 30 October 1991, attached to gastropod shell.

Capitulum regularly oval; carina simply bowed; tergum almost triangular; scutum subtriangular; upper latus large, perfectly calcified part irregularly triangular, constricted above; rostral latus quadrangular; peduncle at least half as long as capitulum.

Capitulum compressed; 13 plates completely covered by fine, hairless membrane. Peduncle half length of capitulum, stout, cylindrical, armed with small, transversely elongated plates. Scutum subtriangular, lateral margin excavated with tooth above excavation blunt, short, simple; tergum almost triangular, scutal margin excavated, but not very boldly, occludent margin slightly, regularly convex outwards. Carina simply bowed, umbo subterminal, in contact with terga above or just entering between them. Cirrus I unequal, anterior ramus oval, posterior ramus slender, long; cirri II–VI slender, long, rami almost equal lengths; cirrus VI with long, slender caudal appendages. Maxillule slightly notched, two major setae on upper side; mandible with four teeth. Measurements of specimen: height of capitulum 18.88 mm, width 11.41 mm, thickness 6.30 mm; length of peduncle 11.45 mm, width 4.89 mm.

Gulf of Oman, Arabian Sea, Sri Lanka, Japan (Chan et al. 2009b). In this study, Annandaleum laccadivicum was found at Tanimbar Island, Indonesia.

Laccadive Sea, 2,077 m depth; on living shells of Dentalium (Annandale 1906).

Figure 15. 

Annandaleum laccadivicum (Annandale, 1906) (MNHN-IU-2019-4931). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. rostral view showing the capitulum and peduncle; d. carinal view. Scale bar: 5 mm (a–d).

– Tanimbar Island: 10 specimens, MNHN-IU-2019-4915, Stn. CP 52, 08°03'S, 131°48'E, 1244–1266 m depth, 30 October 1991; 1 specimen, MNHN-IU-2019-4913, Stn. CP 53, 08°18'S, 131°41'E, 1026–1053 m depth, 30 October 1991; 1 specimen, MNHN-IU-2019-14, Stn. CP 89, 08°39'S, 131°08'E, 1058–1084 m depth, 5 November 1991, attached to pumice.

Capitulum narrow; carinal margin strongly curved; laterally compressed; bearing fourteen imperfectly formed, thin, smooth, translucent plates, eight formed like a Greek lambda.

Capitulum with 14 plates. Peduncle shorter than capitulum, cylindrical, rather slender, expanded at base. Tergum lambda-shaped, with prominent tooth on carinal margin just above point where apex of carina approaches it. Scutum shaped similarly, but occludent branch much stouter, with vertical ridge running nearer to lateral than occludent margin. Cirrus I unequal, anterior ramus oval, posterior ramus slender, long; cirri II–VI slender, long, with rami almost equal length; cirrus VI with long, slender caudal appendages. Maxillule not notched, two major setae on upper side; mandible with four teeth including inner angle. Measurements of five specimens: height of capitulum 16.61–24.27 mm, width 8.73–14.49 mm, thickness 3.17–6.31 mm; length of peduncle 5.54–15.27 mm, width 3.73–6.26 mm.

Indo-Pacific from off Zanzibar, Indian Ocean, eastern Australia; Sumbawa, Indonesia; Malay Arch.; SW of Calatagan Pt, Philippines; S Japan (S of Honda I.), SW Pacific; attached to shells of bivalves; 234–2077 m depth (Jones and Hosie 2016). In this study, Annandaleum lambda was found at Tanimbar Island, Indonesia.

Eastern Indian Ocean (13°54'15"N, 94°02'15"E), Investigator Stn. 372; 1,176 m depth (Jones 1992).

Figure 16. 

Annandaleum lambda (Annandale, 1910) (MNHN-IU-2019-4915). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. rostral view showing the capitulum and peduncle; d. carinal view. Scale bar: 6 mm (a–d).

Capitulum with 14 plates, mostly not reduced; tergum with straight basal margin or shallow notch; scutum with straight, smooth basal margin; upper latus triangular or elongate, commonly with slightly hollowed-out basal margin, rarely with deep notch; inframedian latus narrow, triangular or quadrilateral, umbo apical; caudal appendages present.

Litoscalpellum fissicarinatum Newman & Ross, 1971: 108, pl. XC, text-fig. 55.

– Tanimbar Island: 5 specimens, MNHN-IU-2019-4896, stn. CC 56, 08°16'S, 131°59'E, 549–552 m depth, 31 October 1991; 1 specimen, MNHN-IU-2019-4898, stn. CP 71, 08°38'S, 131°44'E, 477–480 m depth, 2 November 1991; 6 specimens, MNHN-IU-2019-4901, stn. CP 72, 08°36'S, 131°33'E, 676–699 m depth, 2 November 1991.

Capitulum compressed, oval, notched above; surface covered with very short velvety pubescence, areas of valves defined by grooves, lines of growth strongly marked; carina flattened.

Capitulum with 14 plates, cartilaginous thick. Terqum irregularly triangular, apex projecting above carina, recurved. Scutum triangular, basal width more than half height, apex overlapping tergum. Carina evenly curved, apex projecting freely for short distance, touching or entering between terga, its base rounded, widely separated from carinal latera; roof strongly convex. Upper latus triangular with base convex. Rostrum triangular; inframedian latus small, triangular, base deeply embedded. Peduncle with large transverse plates, not overlapping (widely spaced). Cirrus I unequal, anterior ramus oval, posterior ramus slender, long; cirrus VI with caudal appendages. Maxillule with oral edge sinuous, a large seta at its proximal third, another at its distal end; mandible with four teeth. Measurements of five specimens: height of capitulum 16.94–39.25 mm, width 11.39–28.28 mm, thickness 5.20–19.89 mm; length of peduncle 15.02–52.02 mm, width 5.63–16.87 mm.

In this study, Litoscalpellum juddi was found at Tanimbar Island, Indonesia.

11°0'S, 121°30'E (Java-Australia), 720 m depth (Calman 1918b).

Figure 17. 

Litoscalpellum juddi (Calman, 1918) (MNHN-UI-2019-4898). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. rostral view showing the capitulum and peduncle; d. carinal view. Scale bar: 11 mm (a–d).

– Kei Islands: 1 specimen, MNHN-IU-2019-4934, Stn. CP 05, 05°49'S, 132°18'E, 296–299 m depth, 22 October 1991; 1 specimen, MNHN-IU-2019-4936, Stn. CP 09, 05°23'S, 132°29'E, 368–389 m depth, 23 October 1991.

– Tanimbar Island: 4 specimens, MNHN-IU-2019-4935, Stn. CP 83, 09°23'S, 131°00'E, 285–297 m depth, 4 November 1991; 16 specimens, MNHN-IU-2019-4937, Stn. CP 69, 08°42'S, 131°53'E, 356–368 m depth, 2 November 1991.

Capitulum plates separated, covered by fine membrane; carina slightly angularly bent; upper latus trapeziform; inframedian latus triangular; peduncle with scattered, calcareous scales.

Capitulum with 14 plates, lines of growth not distinct, plates separated by broad, membranous interspaces. Scutum elongate quadrangular, broader at base than in upper half; umbo apical, slightly projecting outwards. Tergum triangular; carina bowed; upper latus trapeziform; inframedian latus very small, triangular. Peduncle cylindrical with numerous calcareous scales scattered over surface. Cirrus I with rami unequal, anterior ramus oval, posterior ramus slender, long, segments very hairy. Maxilla bilobed; maxillule notched, two large setae above notch; mandible with three teeth, inferior angle pectinated. Measurements of five specimens: height of capitulum 16.15–26.05 mm, width 9.24–16.59 mm, thickness 4.45–8.18 mm; length of peduncle 7.25–20.90 mm, width 4.13–8.95 mm.

Indian Ocean, Antarctic and Southern (South of the Kerguelen Islands); known depth range 195 to 274 m (Shalaeva and Boxshall 2014). In this study, Litoscalpellum recurvirostrum was found at Kei Islands and Tanimbar Island, Indonesia.

Between Kerguelen and Heard Islands; 52°4'S, 71°22'E; depth: 270 m; bottom temperature: 1.8 °C; bottom: rocks (Hoek 1883).

Figure 18. 

Litoscalpellum recurvirostrum (Hoek, 1883) (MNHN-UI-2019-4934). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. rostral view showing the capitulum and peduncle; d. carinal view. Scale bar: 6 mm (a–d).

– Tanimbar Island: 1 specimen, MNHN-IU-2019-4927, Stn. CP 91, 08°44'S, 131°05'E, 884–891 m depth, 5 November 1991.

Capitulum with 14 plates; inframedian latus triangular, very small, narrow; carina with flat roof; rostrum minute; scutum lacking prominent apicolateral arm; maxilla subtriangular, slightly trilobate; maxilulle slightly notched with teeth diverging laterally from cutting edge; caudal appendage multi-articulate, slightly shorter than first segment of cirrus VI.

Capitulum elongate, higher than broad; plates ornamented with growth lines. Carina bowed, roof slightly convex, bounded by angles. Tergum triangular; scutum with lateral margin concave; upper latus roughly quadrangular; carinal latus higher than wide; rostral latus quadrangular, slightly broader than high; rostrum minute, narrow, essentially rectangular. Cirrus I unequal, anterior ramus shorter, broader than posterior ramus; both rami densely covered with long setae. Mandible with four teeth including inferior angle, inferior angle serrate along basal margin with four spines. Measurements of specimen: height of capitulum 14.56 mm, width 8.09 mm, thickness 2.50 mm; length of peduncle 7.52 mm, width 3.89 mm.

Southeast Pacific Ocean (Newman and Ross 1971). In this study, Litoscalpellum walleni was found at Tanimbar Island, Indonesia.

northeast of Peter I Island, southeast Pacific Ocean; 65°50'S, 88°56'W; depth: 4,502 m (Newman and Ross 1971).

Figure 19. 

Litoscalpellum walleni Newman & Ross, 1971 (MNHN-UI-2019-4927). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. rostral view showing the capitulum and peduncle; d. carinal view. Scale bar: 4 mm (a–d).

Capitulum with plates packed very closely; carina slightly convex; umbo of scutum and tergum apical.

Arcoscalpellum Hoek, 1907: 57.

Capitulum of female or hermaphrodite with 13 or 14 completely calcified plates; scutum and tergum with umbones apical; carina evenly bent, umbo apical or subapical; middle latera narrowly triangular, baton-like, small, umbo apical, not reaching upper latera; carinolatera typically with umbo orientated in middle part of carinal area, not extending beyond rim of capitulum; caudal appendages usually uni-articulate, but possibly absent or extended to seven segments; basically females with dwarf males.

Scalpellum manum Zevina, 1973: 843, figs 1–7; type locality: Indian Ocean, 12°18'S, 112°43'E.

– Tanimbar Island: 2 specimens, MNHN-IU-2019-4922, Stn. CC 21, 05°14'S, 133°00'E, 688–694 m depth, 25 October 1991, attached to glass rope sponge.

Capitulum triangular; plates ornamented with radial ridges, covered by sparsely hirsute integument; carina with roof deeply grooved; scutum with apex overlapping tergum; inframedian latus triangular, very small.

Desciption. Capitulum yellowish, with 13 fully calcified plates. Peduncles short with scales slightly overlapping in the middle part. Scutum with pit for complemental males, above shallow pit for adductor muscle. Carina wide in lower part, ribbed in upper part. Upper latus with straight sides; rostrum appearing externally as inverted triangle. Cirrus I unequal, anterior ramus oval, posterior ramus slender, long; cirrus VI with very short caudal appendages. Maxillule with notch between two or three stout setae at upper angle, group of more slender setae on cutting edge; mandible with three teeth excluding inferior angle; labrum cutting edge slightly concave, numerous pointed teeth on cutting edge. Measurements of two specimens: height of capitulum 12.44–13.88 mm, width 6.97–7.52 mm, thickness 2.77–3.47 mm; length of peduncle 2.99–3.15 mm, width 2.94–3.24 mm.

Indian Ocean, Eastern and Western; Pacific, Southwest and Western Central; Atlantic, Southeast and Eastern central; 110–2,397 m depth (Shalaeva and Boxshall 2014). In this study, Amigdoscalpellum costellatum was found at Tanimbar Island, Indonesia.

1. Station 135: Island of Tristan da Cunha; depth: 110 m, 137 m, 183 m, 274 m, 1,006 m, 1,829 m, 2,012 m; bottom: rocky, shells. 2. Station 164a: off Sydney, 34°13'S, 151°38'E; depth: 750 m; bottom: grey ooze. 3. Station 169: off East Cape, Auckland, 37°34'S, 179°22'E; depth: 1,280 m; bottom temperature: 4.2 °C; bottom: grey ooze (Hoek 1883).

Figure 20. 

Amigdoscalpellum costellatum (Withers, 1935) (MNHN-IU-2019-4922). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. carinal view; d. rostral view showing the capitulum and peduncle. Scale bar: 3 mm (a–d).

– Kei Islands: 1 specimen, MNHN-IU-2019-4921, Stn. CP 20, 05°15'S, 132°59'E, 769–809 m depth, 25 October 1991.

Capitulum with 13 fully calcified plates; carina slightly bowed, umbo at apex; upper latus trapeziform; inframedian latus small, narrow; carinal latus not projecting beyond carina; peduncle short, cylindrical.

Capitulum yellowish, elongate-oval shape; surface with distinct lines of growth. Carina large, simply bowed. Scutum with umbo at apex, slightly recurved, projecting slightly over tergum; tergum triangular, stout, broad, apex recurved, scutal margin almost straight. Upper latus quadrangular, apex slightly projecting over scutum. Rostral latus quadrangular, scutal and basal margins parallel. Carinal latus quadrangular, carinal margin almost straight. Cirrus I unequal, anterior ramus oval, posterior ramus more slender. Maxillule with notch between two or three stout setae at upper angle, a group of more slender setae on cutting edge; mandible with three teeth excluding inferior angle; labrum with numerous blunt teeth on straight, cutting edge. Measurements of specimen: height of capitulum 7.26 mm, width 3.74 mm, thickness 1.40 mm; length of peduncle 3.00 mm, width 1.99 mm.

Indian Ocean, Antarctic and Southern (North East of Prince Edward Island); known depth 2,516 m (Shalaeva and Boxshall 2014). In this study, Amigdoscalpellum tenue was found at Kei Islands, Indonesia.

46°46'S, 45°31'E; depth: 2,475 m; bottom temperature: 1.5 °C; bottom: globigerina ooze (Hoek 1883).

Figure 21. 

Amigdoscalpellum tenue (Hoek, 1883) (MNHN-IU-2019-4921). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. carinal view showing the capitulum and peduncle; d. rostral view showing the capitulum and peduncle. Scale bar: 2 mm (a–d).

Capitulum with 13 or 14 plates; inframedian latus very narrow, bacilliform, umbo sub-medial; umbo of upper latus apical or sub-apical; carinal latus broad, umbo sub-basicarinal, not extending beyond carinal margin; caudal appendages long.

Scalpellum recurvitergum Gruvel, 1902; type locality: Atlantic Ocean, SW of Azores.

– Tanimbar Island: 1 specimen, MNHN-IU-2019-4933, Stn. DW 02, 05°47'S, 132°13'E, 209–240 m depth, 22 October 1991.

Capitulum smooth, elongate, 14 fully calcified plates; inframedia latus rectangular, not constricted; rostrum large, ovo-triangular; caudal appendages short.

Capitulum long, narrow, sparsely covered with hairs, plates separated by narrow, chitinous interspaces, marked with growth lines. Occludent margin strongly convex; carinal margin irregularly straight; apex slightly retroverted towards carinal side. Carina long, simply bowed; roof flat; parietes well developed towards distal half of plate. Tergum triangular, occludent margin short, convex, scutal and basal margins almost straight, carinal margin concave. Scutum with umbo apical, overlapping occludent margin of tergum. Upper latus triangular; carinal latus twice as long as broad; inframedian latus rectangular; rostral latus nearly rectangular in outline; rostrum large, elongate triangular, broad above, pointed below. Cirrus I unequal, anterior ramus oval, posterior ramus more slender; cirrus VI with caudal appendages. Maxillule not notched stout spine along the cutting edge; mandible with three teeth excluding inferior angle. Measurements of specimen: height of capitulum 9.67 mm, width 5.52 mm, thickness 2.58 mm; length of peduncle 2.79 mm, width 2.29 mm.

East China Sea, Pacific Ocean, Taiwan (Chan et al. 2009b). In this study, Catherinum rossi was found at Tanimbar Island, Indonesia.

Stn. 3, Hess Guyot (17°53.2'N, 174°24.8'W), 1,692–1,735 m depth (Sigsbee beam trawl); Stn. 1, Allison Guyot (18°31.0'N, 179°36.0'W), 1,413–1,645 m depth (otter trawl) (Rao and Newman 1972).

Figure 22. 

Catherinum rossi (Rao & Newman, 1972) (MNHN-IU-2019-4933). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. rostral view showing the capitulum and peduncle; d. carinal view. Scale bar: 3 mm (a–d).

Upper latus with umbo on scutal margin; inframedian latus with umbo apical or sub-basal; carinal latus with umbo on carinal part, may be protruding.

Scalpellum planum Hoek, 1883; type locality: 42°42'S, 134°10'E; depth: 4,755 m; bottom temperature: 0.2 °C; bottom: red clay.

– Tanimbar Island: 2 specimens, MNHN-IU-2019-4928, Stn. DW 49, 08°00'S, 132°59'E, 206–210 m depth, 29 October 1991.

Capitulum with 13 plates separated from each other by distinct chitinous interspaces; scutum almost triangular; upper latus hexagonal, large.

Capitulum flattened, elongate-oval shape; plates with distinct growth lines, separated from each other by rather broad chitinous interspaces. Scutum triangular, occludent margin arched, umbo of scutum apical, apex slightly turned upwards. Tergum triangular, occludent margin not very long. Carina simply bowed. Upper latus irregularly hexagonal, rostral latus irregularly quadrangular, infra-median latus in the form of wine-glass, carinal latus irregularly quadrangular. Peduncle short, with very small, numerous, calcareous scales. Cirrus I unequal, anterior ramus oval, posterior ramus more slender; cirrus VI with short caudal appendages. Maxillule notched, three stout spines on the upper side; mandible with three teeth, excluding inferior angle. Measurements of two specimens: height of capitulum 6.80–7.90 mm, width 3.68–4.36 mm, thickness 1.24–1.26 mm; length of peduncle 1.39–2.49 mm, width 1.80–2.04 mm.

Pacific, Western Central; known depth range 1,302 to 2,745 m (Shalaeva and Boxshall 2014). In this study, Planoscalpellum distinctum was found at Tanimbar Island, Indonesia.

2°33'S, 144°4'E; depth: 1,926 m; bottom temperature: 2.1 °C; bottom: Globigerina ooze (Hoek 1883).

Figure 23. 

Planoscalpellum distinctum (Hoek, 1883) (MNHN-IU-2019-4928). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. rostral view showing the capitulum and peduncle; d. carinal view. Scale bar: 2 mm (a–d).

Capitulum with 13 or 14 plates; carinal lateral umbo at basi-carinal angle, angle not extending beyond carinal margin; inframedian latus triangular or rod-like-shaped, umbo apical or sub-apical; caudal appendage multi-segmented.

Scalpellum spicatum Zevina, 1975.

– Kei Islands: 1 specimen, MNHN-IU-2019-4917, Stn. CP 35, 06°08'S, 132°45'E, 390–502 m depth, 27 October 1991.

– Tanimbar Island: 1 specimen, MNHN-IU-2019-4918, Stn. CP 59, 08°20'S, 132°11'E, 399–405 m depth, 31 October 1991.

Capitulum compressed, elongated; 14 plates, sculptured with radiating ribs; inframedian latus triangular; rostro-lateral plates very low; penis and caudal appendages absent.

Capitulum with all plates strongly ribbed, lines of growth marked by fine, inconspicuous striation. Tergum with occludent margin straight, carinal margin convex, but straight concave near apex. Scutum with occludent margin convex, other margins straight, apex slightly overlapping tergum. Carina evenly curved with flat roof bordered by strong ridges; upper latus quadrangular; rostrum small, triangular, overlapped at sides by rostral latera; inframedian latus very narrow. Peduncle shorter than capitulum, covered with strong scales. Cirrus I with unequal rami (anterior ramus: 11 segmented, posterior ramus: 13 segmented). Maxilla globular with serrulate setae; maxillule not notched; mandible with three major teeth, lower margin with three to four denticles. Measurements of two specimens: height of capitulum 12.07–18.59 mm, width 6.17–11.47 mm, thickness 2.68–5.41 mm; length of peduncle 6.30–8.33 mm, width 3.21–5.41 mm.

Java Sea, Indonesia; Philippines (Chan 2009). In this study, Teloscalpellum ecaudatum was found at Kei Islands and Tanimbar Island, Indonesia.

Java Sea; 7°35'S, 114°30'30"E; 132–315 m depth (Calman 1918b).

Figure 24. 

Teloscalpellum ecaudatum (Calman, 1918) (MNHN-IU-2019-4917). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. carinal view; d. rostral view showing the capitulum and peduncle. Scale bar: 5 mm (a–d).

Capitulum of female or hermaphrodite with 13 or 14 completely calcified plates; tergum and scutum with umbones apical; middle latera triangular, sometimes quadrangular, with apical umbo reaching upper latera; carinolatera triangular or subtriangular with apical umbo; caudal appendages distinctly long.

Scalpellum balanoides Hoek, 1883: 129, pl. V, fig. 15, pl. X, fig. 11, pl. XI, figs 1–3; type locality: 5°42'S, 132°25'E; depth: 236 m; bottom: mud; it was found attached to an arm of a Comatula or Pentacrinus.

– Kei Islands: 1 specimen, MNHN-IU-2019-4923, Stn. CP 16, 05°17'S, 132°50'E, 330–350 m depth, 24 October 1991, attached to crinoid.

– Tanimbar Island: 2 specimens, MNHN-IU-2019-4924, Stn. CP 86, 09°26'S, 131°13'E, 223–225 m depth, 4 November 1991.

Capitulum with 13 fully calcified plates, covered by thin membrane; carina and extremely short, simply bowed without distinct roof; umbo of carina at apex; upper latus triangular; carinal latus almost as high as carina, umbo apical, carinal latus very large, almost similar size to tergum.

Capitulum flat, narrow at base, same breadth as peduncle. Scutum about twice as long as broad; occludent margin almost straight, umbo at apex. Tergum triangular, the same size as scutum. Carina very short, simply, not very strongly, bowed, umbo at apex. Upper latus triangular, carinal margin absent. Rostral latus quadrangular, umbo at apex of angle formed by rostral and scutal margins. Infra-median latus elongate, triangular, umbo apical. Carinal latus very large, convex, umbo at top of carinal margin. Cirrus I unequal, posterior ramus more slender than anterior ramus; cirrus VI with caudal appendages. Maxillule distinctly notched, two stout spines on upper side; mandible with three teeth excluding inferior angle. Measurements of specimen: height of capitulum 8.20 mm, width 4.40 mm, thickness 1.75 mm; length of peduncle 5.06 mm, width 2.10 mm.

Pacific, Western Central; South and East China Sea; South of Sumatra, Banda Sea, Indonesia; Vietnam; Philippines; Taiwan; South of Japan; attached to crinoids, hydroids; 220–1,097 m depth (Jones et al. 2001; Chan et al. 2009b; Shalaeva and Boxshall 2014). In this study, Trianguloscalpellum balanoides was found at Kei Islands and Tanimbar Island, Indonesia.

5°42'S, 132°25'E; depth: 232 m; bottom: mud; attached to arm of a Comatula or Pentacrinus (Hoek 1883).

Figure 25. 

Trianguloscalpellum balanoides (Hoek, 1883) (MNHN-IU-2019-4923). а . left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. rostral view showing the capitulum and peduncle; d. carinal view. Scale bar: 2 mm (a–d).

– Tanimbar Island: 1 specimen, MNHN-IU-2019-4908, Stn. CP 91, 08°44'S, 131°05'E, 884–891 m depth, 5 November 1991.

Capitulum with 14 plates covered by membrane, covered by very long hairs; carina simply bowed, umbo at apex, roof flat; upper latus triangular; rostrum very narrow stripe distinctly visible at surface.

Capitulum small, long hairs covering plates. Scutum elongate, convex, more than twice as long as broad. Tergum large, elongate rhomboid, umbo at apex. Carina simply bowed, roof flat. Upper latus almost triangular, carinal-basal margin arched. Rostrum small, linear-shaped. Rostral latus quadrangular, basal and scutal margins parallel. Infra-median latus triangular, umbo apical. Carinal latus with irregular shape, umbo near apex. Peduncle short. Cirrus I with rami unequal, anterior ramus oval, posterior ramus more slender; cirrus VI with caudal appendages. Maxillule not notched, two stout spines on upper side; mandible with three teeth excluding inferior angle. Measurements of the specimen: height of capitulum 12.18 mm, width 6.50 mm, thickness 3.74 mm; length of peduncle 4.10 mm, width 3.43 mm.

Borneo, Indonesia; Pacific, Western Central and Southeast; Australia; Taiwan; Antarctica; attached to gastropod shells, rocks; 1,502–1,965 m depth (Chan et al. 2010; Jones 2012; Shalaeva and Boxshall 2014). In this study, Trianguloscalpellum hirsutum was found at Tanimbar Island, Indonesia.

Pacific, Western Central (Moluccas Sea); 0°48'S, 120°58'E; depth: 252 m; bottom temperature: 2.4 °C; bottom: rock (Hoek 1883).

Figure 26. 

Trianguloscalpellum hirsutum (Hoek, 1883) (MNHN-IU-2019-4908). а . left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. carinal view; d. rostral view showing the capitulum and peduncle. Scale bar: 5 mm (a–d).

Capitulum of female or hermaphrodite, with 13–14 completely calcified plates; tergum with carinal margin straight or slightly to moderately recurving; scutum with or without short apico-lateral arm, umbo apical; carina with apical or subapical umbo, evenly curved or angularly flexed; upper latera sub-triangular or pentagonal, umbo apical or subapical; middle latera narrow, triangular or quadrangular, umbo basal or sub-basal; carinolatera short, umbo basal to sub-basocarinal, usually not or slightly projecting beyond rim of capitulum; caudal appendages short.

Scalpellum zenkevichi Zevina, 1972: 44, fig. 3; type locality: Pacific Ocean, 24°27'S, 70°42'E.

– Tanimbar Island: 1 specimen, MNHN-IU-2019-4930, Stn. CP 86, 09°26'S, 131°13'E, 223–225 m depth, 4 November 1991.

Capitulum with 13 plates closely locked together, surface smooth with slightly prominent ridges; carina simply bowed with flat roof; upper latus trapeziform; inframedian latus elongate, narrow; carinal latus with umbo projecting beyond carina.

Capitulum elongate-oval, flat with distinct ridges and furrow. Scutum slightly convex, umbo apical, occludent margin arched. Tergum triangular, umbo apical, distinctly recurved. Rostral latus irregularly quadrangular; infra median latus narrow, umbo near base; carinal latus quadrangular. Peduncle slightly conical, short, scales near capitulum larger than those near base. Cirrus I unequal, anterior ramus oval, posterior ramus more slender; cirri II to VI very long, rami subequal, segments elongate; cirrus VI with caudal appendages. Maxillule not notched, large spine on upper side, cutting edge almost straight; mandible with three large teeth excluding inferior angle. Measurements of specimen: height of capitulum 10.33 mm, width 6.09 mm, thickness 2.08 mm; length of peduncle 4.62 mm, width 2.24 mm.

Indian Ocean, Western; Pacific Western Central and Southeast; Zanzibar; known depth range 463–2,561 m (Shalaeva and Boxshall 2014). In this study, Verum australicum was found at Tanimbar Island, Indonesia.

between New Guinea and Australia (12°08'S, 145°10'E): Challenger station 184: depth: 2,561 m: bottom temperature: 1.8 °C; substrate grey ooze (Hoek 1883).

Figure 27. 

Verum australicum (Hoek, 1883) (MNHN-IU-2019-4930). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. rostral view showing the capitulum and peduncle; d. carinal view. Scale bar: 3 mm (a–d).

– Kei Islands: 1 specimen, MNHN-IU-2019-4920, Stn. DW 18, 05°18'S, 133°01'E, 205–212 m depth, 24 October 1991.

Capitulum with 14 plates separated by chitinous interspaces, surface smooth; carina bowed, angularly bent, with flat roof; upper latus irregular pentagonal; inframedian latus large, wine-glass-shaped.

Capitulum elongate, plates covered by thin, chitinous membrane. Scutum elongated, apex pointed, occludent margin very convex. Tergum flat, triangular, apex very recurved, occludent margin very arched. Carina with umbo at top of flat roof. Upper latus flat, irregular pentagonal; rostrum narrow, elongated; rostral lateral convex with rostral margin short; inframedian latus wine-glass-shaped; carinal latus flat, large. Peduncle short, calcareous scales distinct. Cirrus I unequal, anterior ramus broader than posterior ramus; cirri II to VI long, rami equal; cirrus VI with caudal appendages. Maxillule not notched, two large spines on upper side, cutting edge almost straight; mandible with three large teeth excluding inferior angle. Measurements of specimen: height of capitulum 9.14 mm, width 4.53 mm, thickness 1.74 mm; length of peduncle 2.54 mm and width 2.20 mm.

Atlantic, excluding polar areas; Pacific, Southeast. Known depth range 600 to 2,400 m (Shalaeva and Boxshall 2014). In this study, Verum carinatum was found at Kei Islands, Indonesia.

Station 135, near the Island of Tristan da Cunha; depth: 1,800 m; bottom: rock, shells (Hoek 1883).

Figure 28. 

Verum carinatum (Hoek, 1883) (MNHN-IU-2019-4920). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. rostral view showing the capitulum and peduncle; d. carinal view. Scale bar: 3 mm (a–d).

– Tanimbar Island: 1 specimen, MNHN-IU-2019-4919, Stn. CP 87, 08°47'S, 130°49'E, 1017–1024 m depth, 5 November 1991.

Capitulum with 13 plates covered by very thin, chitinous membrane; carina simply bowed, flat roof with umbo apical; upper latus quadrangular or rather pentagonal, lower edge being truncated; inframedian latus elongate, quadrangular; carinal latus large, elongate, umbo near base; peduncle short.

Capitulum flatted, elongate, plates separated by narrow, chitinous interspaces. Scutum quadrangular, umbo apical, occludent margin arched. Tergum triangular with umbo slightly produced apex. Carina with bowed, flat roof, increasing little in width from upper to lower. Upper latus irregularly trapeziform; rostral latus with umbo at top of rostral margin; infra-median latus irregular, quadrangular, elongate, narrow; carina latus quadrangular. Cirrus I unequal, anterior ramus broader than posterior ramus; cirrus VI with short caudal appendages. Maxillule slightly notched, two large spines on upper side; mandible with three large teeth excluding inferior angle; labrum slightly convex, with numerous teeth. Measurements of specimen: height of capitulum 13.46 mm, width 6.98 mm, thickness 2.99 mm; length of peduncle 6.02 mm, width 3.23 mm.

Indo-west Pacific: Eastern Africa, Gulf of Aden, eastwards to New Zealand; Philippines; Taiwan; attached to sunken wood, gorgonians, glassy spicule of hexactinellid sponges; 822–4850 m depth (Shalaeva and Boxshall 2014; Jones and Hosie 2016). In this study, Verum novaezelandiae was found at Tanimbar Island, Indonesia.

37°34'S, 179°22'E; depth: 1,260 m; bottom temperature: 4.2 °C; bottom: grey ooze (Hoek 1883).

Order SESSILIA Lamarck, 1818

Figure 29. 

Verum novaezelandiae (Hoek, 1883) (MNHN-IU-2019-4919). а. left lateral view showing the capitulum and peduncle; b. right lateral view showing the capitulum and peduncle; c. carinal view; d. rostral view showing the capitulum and peduncle. Scale bar: 3 mm (a–d).

Shell asymmetrical with four plates (carina, rostrum, tergum and scutum), base membranous or calcareous.

Scutum and tergum without depressor muscles; movable only on one side; other side immovable, united with rostrum and carina.

Verrucids with erect form; bases of plates not inflected. Operculum close to vertical, myophore absent.

Verruca hoeki Pilsbry, 1907.

– Tanimbar Island: 3 specimens, MNHN-IU-2019-4941, Stn. CP 91, 08°44'S, 131°05'E, 884–891 m depth, 5 November 1991, attached to peduncle of Alcockianum persona (Annandale, 1916).

Shell not depressed; carina and rostrum interlocking with single rib from each plate; movable plates large, scutum with four articular ribs, tergum with six articular ribs, growth lines very distinct; caudal appendages long.

Shell yellowish. Movable scutum elongately triangular, apex distinctly beaked, projecting freely; surface with numerous articular ridges. Movable tergum large, quadrangular; surface with strongly developed, curved axial articular ridge. Carina and rostrum irregular quadrangular, with carina higher, rostrum broader. Fixed tergum with two parts: (1) triangular portion very narrow at apex, slightly broader in its inferior (2) flat and broad part at a rear portion of shell. Fixed scutum pointed with distinctly beaked apex; composed of broader, nearly flat, triangular portion and narrower inflected portion, only widening towards its inferior. Base of shell elongatedly oval-shaped. Cirrus I with rami very unequal (anterior ramus: 12-segmented, posterior ramus: 28-segmented); cirrus VI with caudal appendages. Maxilla bilobed, fringed with setae, except on the notch; maxillule widely notched, horizontally elongated, two large spines above notch, numerous dense setae at notch; mandible with three teeth excluding inferior angle; labrum slightly concave, conical teeth on cutting margin.

Pacific Ocean (Chan et al. 2010). In this study, Altiverruca navicula was found at Tanimbar Island, Indonesia.

(1) 9°3.4'S, 119°56.7'E; depth 959 m; bottom: globigerina ooze. (2) 3°37.7'S, 131°26.4'E; depth 924 m; bottom: fine grey mud (Hoek 1913).

Figure 30. 

Altiverruca navicula (Hoek, 1913) (MNHN-IU-2019-4941). а. left lateral view; b. right lateral view; c. upper lateral view; d. lower lateral view. Scale bar: 7 mm (a–d).

Shell with four plates (carina, rostrum, scutum and tergum); operculum parallel to base.

Verruca albatrossiana Pilsbry, 1912: 292. – 1916: 47; type locality: East of Luzon, Philippines.

– Kei Islands: 1 specimen, MNHN-IU-2019-4942, Stn. CC 21, 05°14'S, 133°00'E, 688–694 m depth, 25 October 1991, attached to glass rope sponge.

Rostrum and fixed scutum with unusual length; rostrum low, fixed scutum larger than fixed tergum.

Movable plates parallel to base, wall of parietal vertically ribbed; fixed scutum without internal pit. Movable scutum with crescentic ridge and longitudinal striations; movable tergum with articular ribs and diagonal rib. Apices of fixed scutum and tergum contiguous. Carina occupying carino-rostral wall, apices marginal. Cirrus I with rami unequal and serrulate setae; cirrus VI with caudal appendages. Maxilla globular, with fringing setae; maxillule notched, two large setae on upper side; mandible with three teeth excluding inferior angle.

Indo-west Pacific: NW Australia; South China Sea; China; Philippines; attached to cidaroid spines (e.g. Stereocidaris indica philippinensis Mortensen, 1928), 345–620 m depth (Jones and Hosie 2016). In this study, Newmaniverruca albatrossiana was found at Kei Islands, Indonesia.

East of Luzon, Philippines (Pilsbry 1912).

Figure 31. 

Newmaniverruca albatrossiana (Pilsbry, 1912) (MNHN-IU-2019-4942). а. left lateral view; b. right lateral view; c. upper lateral view; d. lower lateral view. Scale bar: 3 mm (a–d).

Peduncle absent; shells bilaterally symmetrical on either side of rostrocarinal axis; shell with parietal plates of carina, rostrum and one to three pairs of lateral plates, all separate from one another, variously fused or totally concrescent; base membranous or calcareous; hermaphroditic or with dwarf males.

Shell with four or six plates; wall solid or permeated by single row of chitin-filled longitudinal canals; radii absent; one or both rami of cirri I and cirri II sometimes antenniform; labrum without notch in crest.

Shell with six plates, infiltrated by chitin-filled tubes; basis calcareous; scuta parallel to basis; tergum with distinct spur; cirrus II resembling cirrus I more than cirrus III.

Hexalasma Hoek, 1913.

Parietes solid; radii absent; plates with a carina, paired carinolatera and latera and a rostrum without any sign of fusion; caudal appendages absent.

Hexelasma velutinum Hoek, 1913: 246 (part.); type locality: Indonesia, 6°08'S, 121°19'E (Siboga Station 105).

– Kei Islands: 2 specimens, MNHN-IU-2019-4851, Stn. DW 18, 05°18'S, 133°01'E, 205–212 m depth, 24 October 1991.

Shell with very wide orifice; alae broadly-triangular with summits oblique; scutum folded longitudinally, articular ridge slightly prominent, deep pit for adductor muscle; tergum beaked, with prominent articular ridge, spur very broadly rounded; inner side of scutum and tergum orange-coloured.

Shell yellowish, conical, with six plates. Orifice diamond-shaped; scutum triangular elongated with protruding growth-ridges; tergum smaller than scutum, apex beaked, carinal margin rounded, growth-ridges less distinct than on scutum. Cirrus I with unequal rami (anterior ramus: 8-segmented; posterior ramus: 12-segmented), dense long setae on surface areas. Cirrus II with equal rami, dense long setae. Cirri IV–VI with equal rami with numerous segments; segments almost without exception furnished with two pairs very long, stiff, needle-like spines along inner faces. Measurements of specimen: basal length of shell 14.32 mm, orifice length 8.00 mm, carinal height 12.39 mm, orifice width 6.49 mm, basal width 13.76 mm.

Arafura Sea, Indonesia; 205–560 m depth (Jones and Hosie 2016). In this study, Hexelasma arafurae was found at Kei Islands, Indonesia.

Indonesia; Siboga stat. 262; 5°54'S, 132°49'E; 560 m depth; bottom: solid bluish-grey mud (Hoek 1913).

Figure 32. 

Hexelasma arafurae Hoek, 1913 (MNHN-IU-2019-4851). а. view from above; b. right lateral view. Scale bar: 4 mm (a, b).

Shell wall composed of four or six plates (rostrum, carina and one to three pairs of laterals); parietes solid or tubiferous, when tubiferous rarely secondarily filled; radii solid or tubiferous. Basis commonly calcareous, solid or permeated by tubes, rarely membranous; when basis calcareous, internal surfaces of compartments commonly with uniform ribs; when calcareous commonly forming complex interdigitations with wall. Opercular plates occlude aperture; articulations between the pairs generally shallow or fused. Cirrus I with rami subequal or grossly unequal; cirri II and III with rami never antenniform; cirrus III resembling II more than IV; caudal appendages absent; penis with basidorsal point. Labrum thin, never bullate; crest with pronounced medial incision; mandible quadri- or quinquedentoid; second and following teeth with one or more subsidiary cusps; fifth tooth often vestigial; inferior angle commonly molariform.

Shell with four or sixplates; parietes solid, rarely tubiferous; tubes uniformly or irregularly arranged; radii solid; basis commonly calcareous, rarely tubiferous.

Shell with four or six plates; parietes solid or tubiferous; when tubiferous, tubes uniformly arranged in single row; interlaminate figures simple; basis calcareous or membranous, when membranous wall solid.

Archaeobalanus Menesini, 1971: 19.

Shell firm, strong, with six thick compartments; parietes with or without pores; radii solid with summits parallel to basal margin of parietes and denticulated sutural margins; basis calcareous, elongated along carino-rostral axis, boat-shaped; orifice smooth, not dentated; scutum with simple growth ridges; penis with basidorsal point; attached to gorgonians or antipatharians.

Conopea elongata Say, 1822; type locality: eastern Florida, USA.

– Kei Islands: 9 specimens, MNHN-IU-2019-4823, Stn. DW 30, 05°39'S, 132°56'E, 111–118 m depth, 26 October 1991; 1 specimen, MNHN-IU-2019-4824, Stn. DW 22, 05°22'S, 133°01'E, 82 m depth, 25 October 1991.

Shell irregularly conical; orifice oval with swollen border; basis irregularly cup-formed; scutum and tergum triangular, not calcified together; spur of tergum feebly developed.

Shell yellowish with orange rust-brown in proximal areas. Carina, carinolatera and latera with pale orange-brown and rust red-brown longitudinal stripes, latter may have oblique white spots. Radii with pale orange-brown and rust red-brown horizontal striation. Opercular plates with scutum pink-brown, transparent; tergum transparent white. Shell may appear longer and lower, due to elongation of carina and rostrum or low and comparatively shorter, due to development of rostrum alone or more upright and comparatively higher, with neither carina nor rostrum elongated. Cirrus I with unequal rami (anterior ramus: 7-segmented; posterior ramus: 12-segmented). Cirri II–VI with equal rami, numerous segments. Penis very long, delicate hairs scattered over surface, a few more disposed near tip. Labrum deeply notched, two small teeth on each side of notch. Mandibles with five teeth, inferior angle not distinctly separated from fifth; distance between tips of first and second teeth slightly more than that between those of second and third teeth; third tooth larger; fourth and fifth smaller than others. Maxillule with straight edge and numerous large setae. Measurements of specimen: basal length of shell 7.73 mm, orifice length 4.60 mm, carinal height 8.70 mm, orifice width 3.88 mm, basal width 4.94 mm.

Indo-west Pacific: Indian Ocean; Gulf of Aden, India, east to Fiji and NW to Indonesia, N Australia, Malay Arch.; China; Philippines; S Japan; Fiji Is; attached to coenosarc of gorgonians or antipatharians; littoral–453 m depth (Jones and Hosie 2016). In this study, Conopea cymbiformis was found at Kei Islands, Indonesia.

Near Madras, India; attached to a gorgonian (Darwin 1854).

Figure 33. 

Conopea cymbiformis (Darwin, 1854) (MNHN-IU-2019-4823). а. left lateral view; b. right lateral view; c. view from above; d. basal view. Scale bar: 3 mm (a–d).

– Tanimbar Island: 12 specimens, MNHN-IU-2019-4821, Stn. CP 82, 09°32'S, 131°02'E, 215–219 m depth, 4 November 1991 attached to gorgonian; 4 specimens, MNHN-IU-2019-4822, Stn. DW 49, 08°00'S, 132°59'E, 206–210 m depth, 29 October 1991, attached to gorgonian.

Shell with parietes and basis not porose; carino-lateral compartments very narrow, almost same width from top to bottom; radii with smooth sutural edges; scutum externally striated longitudinally.

Specimens covered with coenosarc of coral, except orifice. Easily recognisable species due to narrow carino-lateral plate, which is nearly same width at top as bottom; scutum externally longitudinally striated; parietal plates studded with calcareous points. Parietal plates pearly white, solid, superficially appearing to possess longitudinal tubes, growth lines horizontal. Alae moderately developed. Basis calcareous. Size small. Rostrum well developed, concave, lying at angle of ~ 45°. Laterals very well developed. Carino lateral parietes thin, radii and alae well developed. Carina tall, about half width of rostrum. External surfaces of all parietes with very small, calcareous studs, regularly spaced, arranged along horizontal growth lines. Opercular plates sunk down into orifice. Cirrus I with unequal rami (anterior ramus: 5-segmented; posterior ramus: 7-segmented). Cirrus II with unequal rami (anterior ramus: 6-segmented; posterior ramus: 9-segmented). Cirri III–VI with subequal rami more slender, longer, with segments more elongate. Penis very long, tapering towards tip, bearing few, very minute hairs. Maxilulle with straight edge with numerous large setae. Mandibles with five teeth and inferior angle. Measurements of four specimens: basal length of shell 2.23–4.22 mm, orifice length 1.09–2.02 mm, carinal height 2.04–3.09 mm, orifice width 0.94–1.59 mm, basal width 1.79–2.80 mm.

Indo-west Pacific, from Gulfs of Aden and Persia, India, Malaysia, Indonesia, Gulf of Siam, to southern Japan; 45–220 m depth (Jones and Hosie 2016). In this study, Conopea navicula was found at Tanimbar Island, Indonesia.

Madras, India; attached to gorgonian (Darwin 1854).

Figure 34. 

Conopea navicula (Darwin, 1854) (MNHN-IU-2019-4822). a. left lateral view; b. orifice view. Scale bar: 1 mm (a, b).

Shell parietes solid, six plates; radii solid, well developed, with denticulate sutural edges; basis calcareous, solid; complemental male, when present, in pit of rostral plate of hermaphrodite.

Balanus auricoma Hoek, 1913: 198, pl. XVIII, figs 20–22, pl. XIX, figs 1–7; type locality: Ternate, Indonesia (Siboga station 136).

Parietes and radii rather thick, smooth, without pores; basis flat, calcareous; rostrum not very elongated; radii with strongly septate sutural edges; tergal spur narrow; crests for lateral depressor muscles of scutum absent; adductor ridge weak or absent; tergum flat or with shallow furrow without infolded sides; conspicuous teeth on anterior margins of fourth cirri absent.

Balanus auricoma Hoek, 1913: 198, pl. XVIII, figs 20–22, pl. XIX, figs 1–7; type locality: Ternate, Indonesia (Siboga station 136).

– Tanimbar Island: 2 specimens, MNHN-IU-2019-4842, Stn. CP 45, 07°54'S, 132°47'E, 302–305 m depth, 29 October 1991, shell only; 10 specimens, MNHN-IU-2019-4841, Stn. DW 49, 08°00'S, 132°59'E, 206–210 m depth, 29 October 1991, attached to sea urchin spines; 1 specimen, MNHN-IU-2019-4838, Stn. CP 82, 09°32'S, 131°02'E, 215–219 m depth, 4 November 1991, attached to antipatharian; 7 specimens, MNHN-IU-2019-4847, Stn. CP 85, 09°22'S, 131°14'E, 240–245 m depth, 4 November 1991, attached to spines of sea urchin; 63 specimens, MNHN-IU-2019-4850, Stn. CP 86, 09°26'S, 131°13'E, 223–225 m depth, 4 November 1991, attached to spines of sea-urchins.

– Kei Islands: 1 specimen, MNHN-IU-2019-4849, Stn. CP 05, 05°49'S, 132°18'E, 296–299 m depth, 22 October 1991, attached to lateral plate of Chirona tenuis; 1 specimen, MNHN-IU-2019-4844, Stn. CP 12, 05°23'S, 132°37'E, 413–436 m depth, 23 October 1991, attached to antipatharian; 6 specimens, MNHN-IU-2019-4848, Stn. CP 16, 05°17'S, 132°50'E, 330–350 m depth, 24 October 1991, attached to dead gorgonian, spines of sea-urchins, arm of crinoid; 3 specimens, MNHN-IU-2019-4840, Stn. CP 35, 06°08'S, 132°45'E, 390–502 m depth, 27 October 1991; 1 specimen, MNHN-IU-2019-4843, Stn. CP 36, 06°05'S, 132°44'E, 210–268 m depth, 27 October 1991.

Shell flatly-conical, colour reddish basally, whitish apically; radii narrow, summits slightly oblique; opercular plates with golden hairs along occludent margins; scutum with articular ridge slightly prominent, adductor ridge absent; tergum narrow, scutal margin distinctly dentated.

Shell with plates ribbed longitudinally. Shell colour brownish-pink to dull rose-pink, ribs tending to white, colour often faded with specimens appearing uniform white. Parietes of carinolatera very narrow, with single, conspicuous, longitudinal ridge. Scutum with occludent margin straight, surface indistinctly ridged, pit for adductor muscle scarcely visible. Tergum short, narrow, scutal margin straight, unusually distinctly dentated, carinal margin short, convex, depressor muscle crests moderately well developed. Opercular plates with long, golden setae fringing occludent margins, especially distally. Cirri I–II with rami slightly unequal, covered with setae; cirri III–VI longer, more slender, dense setae on inner face. Mandible with four teeth, second to fourth with accessory cusps, lower angle molariform with three blunt cusps in series, lower edge with row of stiff setae. Measurements of five specimens: basal length of shell 6.11–8.18 mm, orifice length 4.18–5.83 mm, carinal height 4.11–6.30 mm, orifice width 2.58–3.19 mm, basal width 4.51–5.96 mm.

Banda Sea (Moluccas, Indonesia); SW Australia; New Zealand; New Caledonia; Philippines to southern Japan; Malaysian water; Gulf of Oman, Persia. 27–502 m depth (Jones and Hosie 2016). In this study, Solidobalanus auricoma was found at Kei Islands and Tanimbar Island, Indonesia.

Ternate anchorage; 27 m depth; bottom: mud and stone; numerous specimens on the surface of pieces of rock (Hoek 1913).

Figure 35. 

Solidobalanus auricoma (Hoek, 1913) (MNHN-IU-2019-4850). a. upper lateral view from above; b. left lateral view; c. right lateral view; d. basal view. Scale bar: 2 mm (a–d).

– Kei Islands: 46 specimens, MNHN-IU-2019-4818, Stn. CP 25, 05°30'S, 132°52'E, 336–346 m depth, 26 October 1991, 30 specimens attached to gorgonian, 16 specimens attached to coral; 6 specimens, MNHN-IU-2019-4825, Stn. CP 27, 05°33'S, 132°51'E, 304–314 m depth, 27 October 1991; 1 specimen, MNHN-IU-2019-4826, Stn. CP 05, 05°49'S, 132°18'E, 296–299 m depth, 22 October 1991, attached to crinoid; 13 specimens, MNHN-IU-2019-4827, Stn. CP 16, 05°17'S, 132°50'E, 330–350 m depth, 24 October 1991; 2 specimens, MNHN-IU-2019-4828, Stn. DW 22, 05°22'S, 133°01'E, 82 m depth, 25 October 1991, 1 specimen attached to gorgonian stem; 8 specimens, MNHN-IU-2019-4830, Stn. CP 05, 05°49'S, 132°18'E, 296–299 m depth, 22 October 1991, 5 specimens attached to gorgonian, 1 specimen attached to crinoid.

– Tanimbar Island: 11 specimens, MNHN-IU-2019-4839, Stn. CP 86, 09°26'S, 131°13'E, 223–225 m depth, 4 November 1991, several specimens attached to spines of sea urchins (associated with Solidobalanus auricoma (Hoek, 1913)).

Shell with smooth, glossy white plates, coloured stripes absent; internal plates with thick, solid, finely ribbed longitudinally; base non-porous, radially ribbed.

Shell plates white, stripes absent. Several specimens with pale pink tinge, one with pale brownish-pink parietes with small, narrow ellipsoidal whitish spots, latter orientated longitudinally producing reticulated effect. Radii whitish, pink tinge along distal borders. Scutal growth lines without longitudinal striations; articular ridge absent; pit for adductor muscle small, round. Tergum with shallow, wide furrow running from apex to base. Cirrus I with unequal (anterior ramus: 7-segmented; posterior ramus: 15-segmented). Cirrus II with rami subequal (anterior ramus: 11-segmented; posterior ramus: 12-segmented). Cirri I and II with very dense, long setae on surface areas. Cirri III–VI with rami slightly subequal, rounded. Penis sturdy, not long. Labrum with very shallow notch, three or four irregularly arranged, blunt teeth on each side. Maxillule with distinct, narrow notch with two large setae on upper side. Mandibles with five teeth, second and third bifid and fifth is rudimentary. Measurements of five specimens: basal length of shell 6.23–12.08 mm, orifice length 4.63–9.62 mm, carinal height 3.48–13.22 mm, orifice width 3.24–6.33 mm, basal width 5.66–9.56 mm.

Manado Bay (Indonesia); Japan (Broch 1931–1932). In this study, Solidobalanus pseudauricoma was found at Kei Islands and Tanimbar Island, Indonesia.

Manado Bay, Indonesia (1°31'N, 124°47'E), 500 m depth; Japan (32°25'N, 128°33'E), 400 m depth (Broch 1931–1932).

In the type description, Broch (1931–1932) commented that the specimens were white, without stripes. However, several of the specimens collected by KARUBAR had a pale pink tinge and one specimen (from station DW22) had pale brownish-pink parietes with small, narrow ellipsoidal whitish spots, the latter orientated longitudinally, thus producing a reticulated effect. Radii whitish with pink tinge along distal borders.

Figure 36. 

Solidobalanus pseudauricoma (Broch, 1931) (MNHN-IU-2019-4818). a. left lateral view; b. orifice view; c. basal view; d. right lateral view. Scale bar: 4 mm (a–d).

Parietes and radii without pores; radii usually narrow; scutum striated longitudinally with adductor ridge; tergum furrow deep; cirrus I with rami very unequal in length.

Balanus amaryllis var. (a), var. (b) Darwin, 1854: 279, pl. 7, fig. 6a–c.

Unknown.

– Tanimbar Island: 1 specimen (only shell), MNHN-IU-2019-4814, Stn. CP 65, 09°14'S, 132°27'E, 174–176 m depth, 1 November 1991, attached to broken sea urchin shell.

Shell conical; orifice large, pentagonal, toothed; shell colour pinkish, lighter transparent stripes run longitudinally over surface; radii very narrow, reddish, upper margins very oblique; alae broader, lighter colour.

Shell conical; tips of rostrum and carina slightly curved inwards. Orifice large, pentagonal, toothed. Colour yellowish-white, with slightly darker longitudinal lines on main parts of plates. Radii with very oblique summits, broadest a little distance from the orifice, narrower towards basis. Alae broader than radii, summits rounded. Specimen without scutum, tergum and soft parts. Measurements of specimen: basal length of shell 16.76 mm, orifice length 9.13 mm, carinal height 9.89 mm, orifice width 7.24 mm, basal width 15.14 mm.

Arafura Sea, Indonesia. Indo-west Pacific: South and East Africa, Indian Ocean; Australia (N); Singapore; Malay Arch.; Cambodia; Gulf of Thailand; Mouth of Bassac; Vietnam (Bay of Nhatrang; Lien Chien, Tourane; Codor Is); Hong Kong; S China Sea; China; Philippines; Taiwan; Japan (S); attached to rocks, gastropod shells, rusting iron, fouling species; sublittoral, 5–500 m depth (Jones and Hosie 2016). In this study, Striatobalanus amaryllis was found at Tanimbar Island, Indonesia.

Unknown.

Figure 37. 

Striatobalanus amaryllis (Darwin, 1854) (MNHN-IU-2019-4814). a. orifice view; b. right lateral view. Scale bar: 3 mm (a, b).

– Kei Islands: 5 specimens, MNHN-IU-2019-4820, Stn. CC 10, 05°21'S, 132°30'E, 329–389 m depth, 23 October 1991; 1 specimen (shell only), MNHN-IU-2019-4835, Stn. CP 16, 05°17'S, 132°50'E, 330–350 m depth, 24 October 1991.

– Tanimbar Island: 1 specimen, MNHN-IU-2019-4832, Stn. DW 49, 08°00'S, 132°59'E, 206–2010 m depth, 29 October 1991; 1 specimen (shell only), MNHN-IU-2019-4833, Stn. CP 65, 09°14'S, 132°27'E, 174–176 m depth, 1 November 1991; 4 specimens (shell only), MNHN-IU-2019-4834, Stn. CP 79, 09°16'S, 131°22'E, 239–250 m, 3 November 1991; 1 specimen (only shell), MNHN-IU-2019-4813, Stn. CP 85, 09°22'S, 131°14'E, 240–245 m, 4 November 1991, attached to shell of gastropod; 2 specimens, MNHN-IU-2019-4819, Stn. CP 86, 09°26'S, 131°13'E, 223–225 m depth, 4 November 1991, attached to gastropod shells.

Shell colour whitish to yellowish; surface smooth, glossy; orifice pentagonal shaped, deeply toothed; radii narrow, summits very oblique, slightly concave; basis solid; scutum with longitudinal striations; tergum with short, rather broad spur.

Shell with six plates, conical; orifice large, distinctly toothed; radii well-developed; basis thin, ribbed, solid. Scutum triangular, not elongated, with longitudinal striations; tergum slightly beaked, exhibiting traces of longitudinal striations, spur short, slightly narrow, depressor crests distinctly developed. Cirri I to VI with rami slightly equal in length, transparent and orange-coloured. Penis rather long, sparse, minute hairs on the surface, tapering towards tip, distinctly hairy at tip. Maxillule with edge slightly straight, all the setae similar sized. Mandibles with five teeth, fourth and fifth small. Measurements of five specimens basal length of shell 18.92–28.30 mm, orifice length 13.78–16.29 mm, carinal height 18.02–20.24 mm, orifice width 10.15–13.70 mm, basal width 20.51–28.03 mm.

Arafura Sea, Indonesia; Indo-west Pacific: S Africa; Persian Gulf; Indian Ocean; Australia (N); Singapore; Malay Arch.; Vietnam; Hong Kong; S China Sea; E China Sea; Philippines; Taiwan; Japan (S); W Pacific; attached to crabs, gastropod, bivalve, shells solitary coral, bark of coconut, gorgonians, antipatharians, stones; 7–551 m depth (Jones and Hosie 2016). In this study, Striatobalanus tenuis was found at Kei Islands and Tanimbar Island, Indonesia.

West of Mindoro, Philippines; 6°8'N, 121°19'E; depth: 275 m, at coral-bottom (Hoek 1913).

Figure 38. 

Striatobalanus tenuis (Hoek, 1883) (MNHN-IU-2019-4820). a. orifice view; b. left lateral view; c. right lateral view; d. basal view. Scale bar: 10 mm (a–d).

Wall of four plates wholly concrescent; parietes solid or tubiferous; when tubiferous, tubes occur between outer lamina and sheath or between external ribs of wall; interlaminate figures complex, essentially arborescent; radii solid; basis calcareous, rarely tubiferous, membranous in Pyrgopsella.

Wall of four plates wholly concrescent; opercular valves normal; tergum with weakly developed lateral depressor muscle crests or crests lacking; when shell concrescent, sheath with paired sulci.

Megatrema Sowerby, 1823, by original designation (Holthuis 1982).

Pyrgomina Baluk & Radwanski, 1967.

Pyrgomina seguenzai Baluk & Radwanski, 1967a: 485.

Pliocene (Piacenzian Stage); Gournes, Iraklion nomarchia, Island of Crete, Greece, 35°06'N, 25°47'E; host coral unknown (Ross and Pitombo 2002).

– Tanimbar Island: 1 specimen, MNHN-IU-2019-4817, Stn. CP 86, 09°26'S, 131°13'E, 223–225 m depth, 4 November 1991, attached to coral.

Shell purple-pinkish, tall, conical; oriface oval; base permeated by pores, expanded out of the coral; tergum and scutum subtriangular.

Shell stands exserted on the coral, externally furnished with ribs, lower part rounded with radiating ribs; oriface oval, small and narrow. Scutum triangular, basal margin curved; tergum triangular with narrow spur. Cirrus I with rami unequal (anterior ramus: 10-segmented; posterior ramus: 15-segmented); posterior ramus of cirrus IV without spines. Maxilla globular; maxillule not notched, eight large setae on straight cutting edge; mandible with five major teeth. Measurements of specimen: basal length of shell 7.46 mm, orifice length 2.42 mm, carinal height 10.45 mm, orifice width 1.41 mm, basal width 6.15 mm.

Pyrgomina sp. was found at Tanimbar Island, Indonesia.

Figure 39. 

Pyrgomina sp. (MNHN-UI-2019-4817). a. orifice view; b. left lateral view; c. right lateral view. Scale bar: 2 mm (a–c).

Shell with four or six plates; parietes tubiferous; tubes arranged in single uniform row formed between inner and outer lamina, supplementary tubes may form basally; interlaminate figures complex, arborescent; radii solid or tubiferous, more-or-less developed; basis calcareous, commonly tubiferous; caudal appendages absent; penis commonly with basidorsal point.

Shell with four or six plates; parietal tubes with one or more rows, commonly transverse septa; radii with transverse teeth on sutural edge with denticles on lower side only; alae not cleft; basis with single tubiferous; scutum with conspicuous adductor ridge; tergum with well-developed depressor muscle crests, growth lines in tergum spur display an obvious change in direction; second maxilla with smooth anterior margin of distal lobe, acuminate setae with enlarged, modified tips.

Shell with four or six plates; parietal tubes with one or more rows, commonly transverse septa; radii with transverse teeth on sutural edge, with denticles on lower side only; alae not cleft; basis with single tubiferous; scutum with conspicuous adductor ridge; tergum with well-developed depressor muscle crests, growth lines in tergum spur display an obvious change in direction; second maxilla with smooth anterior margin of distal lobe, acuminate setae with enlarged, modified tips. Cirrus III with inner face of endopod with pinnate setae, rarely bifurcate (complex) setae.

Balanus amphitrite Darwin, 1854: 240 (part.), pl. 5, fig. 2a–d, i–k, m–o; type locality: Natal, South Africa.

– Tanimbar Island: 4 specimens, MNHN-IU-2019-4815, Stn. CP 52, 08°03'S, 131°48'E, 1244–1266 m depth, 30 October 1991.

Primary parietal tubes with transverse septa; exterior of shell with longitudinal purple striations, horizontal striations absent; tergum short with wide spur; cirri III–VI with erect teeth below posterior angles of distal; cirrus III without complex setae.

Shell six-plated, conical, round; externally smooth, white with groups of well-spaced, dark purple vertical stripes; horizontal striations on shell surface absent. Interior of paries with single row of tubes; radii solid, wide; alae with summits moderately oblique; basis porose, calcareous. Scutum externally striped, occludent margin toothed, lateral depressor muscle pit small. Tergum with spur wider than long, less than its own width from basi-scutal angle. Cirrus I with unequal rami (anterior ramus: 10-segmented; posterior ramus: 16-segmented). Cirrus II with slightly equal rami (anterior ramus: 10-segemented; posterior ramus: 12-segmented). Cirrus III with rami subequal (anterior ramus: 12-segmented; posterior ramus: 13-segmented. Cirri IV–VI with rami subequal, longer, more slender. Penis moderately long, tapering distally, sparse, minute hairs on surface, distinctly hairy distally. Labrum deeply notched, numerous teeth on each side. Maxilla without notch below upper pair of spines, nine spines between upper and lower pairs, few short spines on inferior angle; lower pair of spines usually on slight prominence, which may be sometimes moderately strong or strong. Mandible with five teeth, inferior angle with second tooth bifid. Measurements of four specimens: basal length of shell 5.27–12.10 mm, orifice length 3.81–7.89 mm, carinal height 3.64–5.65 mm, orifice width 2.72–5.22 mm, basal width 4.62–12.03 mm.

Cosmopolitan in tropical and subtropical waters. Bermuda & SE USA to Brazil; England and West Europe to South coast of Africa Red, Black and Mediterranean Seas; Suez Canal; SE Africa; Indian Ocean; Australia; Singapore; Malaysia; Réam (Cambodia); Gulf of Siam; Vietnam; Condor Island; Tang Trien (South Annam); Cauda Nhatrang; Hongay, Tonkin; S China Sea; Hong Kong; China; Bohai Sea; Taiwan; Philippines; Japan; South Honsyu, Kyusyu & Ryukyu Island; Vladivostok; Hawaii; central California to SW Mexico; fouling species; lower littoral to sublittoral (Jones and Hosie 2016). Recently, also recorded from Ambon Island and Saparua Island, Indonesia (Pitriana et al. 2020). In this study, Amphibalanus amphitrite was found at Tanimbar Island, Indonesia.

Natal, on a piece of bamboo (Darwin 1854).

Known as an important fouling species of ships and marine installations. The suggestion of anti-fouling paint on the bases of the specimens examined suggests that these specimens were probably knocked off the ship during trawling operations, explaining the great depth at which these specimens were collected, as the normal depth range is 0–9 m.

Figure 40. 

Amphibalanus amphitrite (Darwin, 1854) (MNHN-IU-2019-4815). a. orifice view; b. right lateral view; c. basal view. Scale bar: 4 mm (a–c).