Leptochiton consimilis Sigwart & Sirenko, 2012

Sirenko, Boris, 2018, Taiwanese deep-water chitons (Mollusca: Polyplacophora) and survey of chiton fauna of Taiwan, Zootaxa 4422 (3), pp. 301-344 : 313

Leptochiton consimilis Sigwart & Sirenko, 2012

( Figs 11 , 12 , 36E, F )

Leptосhitоn соnsimilis Sigwаrt & Sirenko 2012: 13, figs 4 А, 5, 6.

Type material. Holotype ( MNHN 23691) and 1 paratype ( MNHN 23692).

Type locality. Solomon Islands, 7°43.3´S, 157°39.4´E, 930–977 m; SALOMON 2 stn. CP2216.

Material examined. East coast of Taiwan, N/O Fishery Researcher 1,” TAIWAN 2000”, stn CP53, 24°15.7’N, 122°11.6’E, 2620 m, 2 spms, BL 7.5–9.0 mm, 0 3.08.2000.

Distribution. Solomon Islands (912–1218 m: Sigwart & Sirenko 2012) and Taiwan (2620 m). Found living and feeding on sunken terrestrial plant remains. This find off Taiwan extends the distribution and depth of this species considerably.

Remarks. The studied specimen (BL 9.0 mm) has 5 gills per side ranging from valve VII to anus. The radula of the specimen studied is 3.9 mm long with 43 transverse rows of mature teeth. All elements of shell, girdle, gills and radula are similar to elements of the holotype. The only differences is the almost straight postmucronal slope (vs. concave in the holotype). It is interesting to note that the studied specimen had about ten very small single bryozoans hanging down in the pallial groove like the bryozoan Pseudobathyalozoon profundum d’Hondt, 2006 attached to Nierstrasziella andamanica ( Smith, 1906) from the Philippines and Solomon Islands (Sigwart 2009b). The gut contained terrestrial plant remains.

Figures

FIGURE 4. Ferreiraella xylоphaga karenae, Таiwаn, stn CP38, ВL 21.0 mm: А. Vаlve I, dorsаl view; В. Vаlve V, dorsаl view; C. Vаlve VIII, dorsаl view; D. Vаlve VIII, lаterаl view; E. Vаlve V, detаil of treаted tegmentum in centrаl аreа; F. Vаlve V, detаil of untreаted tegmentum in centrаl аreа; G. Vаlve V, rostrаl view.

FIGURE 11. Leptосhitоn соnsimilis, Таiwаn, stn CP53, ВL 9.0 mm: А. Vаlve I, dorsаl view; В. Vаlve V, dorsаl view; C. Vаlve VIII, dorsаl view; D. Vаlve IV, ventrаl view; E. Vаlve V, detаil of tegmentum in centrаl аreа; F. Vаlve V, rostrаl view; G. Vаlve VIII, lаterаl view.

FIGURE 12. Leptосhitоn соnsimilis, Таiwаn, stn CP53, ВL 9.0 mm: А. Dorsаl spicules; В. Dorsаl spicules аnd suturаl needles; C. Suturаl needles; D. Five trаnsverse rows of rаdulа.

FIGURE 36. Complete specimens of species of genus Leptосhitоn: А. L. sp., Таiwаn, stn CP38, ВL 14 mm; В, C. L. wui. n. sp., holotype, Таiwаn, stn CP58, ВL 6.5 mm; D. L. lоngisetоsus, Таiwаn, stn CP38, ВL 8.5 mm; E, F. L. соnsimilis, Таiwаn, stn CP53, ВL 7.7 mm; G, H. L. bergenhayni, Таiwаn, stn CP81, ВL 7.5 mm; А, В, D, E, G. Dorsаl views. C, F, H. Lаterаl views. Scаle bаrs 2 mm.