Loricella profundior ( Dell, 1956 )

Sirenko, Boris, 2021, Composition of the genus Loricella (Mollusca: Polyplacophora: Loricidae) and the description of two new species, Zootaxa 4981 (2), pp. 275-300 : 278-281

Loricella profundior ( Dell, 1956)

( Figs. 1 , C, D, 2–7 )

Paricoplax profundior Dell 1956: 157 , figs. 213–219; O’Neill 1987: 134; Xu 1990: 377.

Loricella profundior, Beu 1967: 478 ; Fitzgerald 1969: 23; Beu 1977: 42; Powell 1979: 25; Kaas 1990: 178 (in part); 1991: 22 (in part); Kaas et al. 2006: 67 (in part); Spencer et al. 2009: 197.

Loricella oviformis, Kaas 1985: 310 (in part, not Squamophora oviformis Nierstrasz, 1905 ).

Sinolorica profundior, Xu 1990: 377 .

Type material. Holotype ( NMNZ M972 ), not seen.

Type locality. New Zealand, Chatham Islands, off the Forty Fours , 238 m.

Material examined. Tonga Islands, Tongatapu, N/O “Alis”, BORDAU 2 stn CP1510, 21°05.5’S, 175°23’W, 461–497 m, 1 spm (MNHN-IM-2013-59980), BL 11.5 mm, 31.05.2000 ; stn CP1545, 21°17’S, 175°17’W, 444–447 m, 1 spm (MNHN-IM-2013-59981), BL 9.0 mm, 05.06.2000 ; stn DW1628, 23°22’S, 176°18’W, 400–416 m, 2 spms (MNHN-IM-2013-59982, MNHN-IM-2013-59983), BL 8.0–11.0 mm, 19.06.2000 ; New Zealand, southern Kermadec Ridge , Rumble V volcano, RVTangaroa, 36°8.80’S, 178°12.20’E, 772–951 m, 1 spm ( NMNZ M.319774), BL 18.0 mm, 23.05.2001 ; Chatham Rise, RVTangaroa, 42°35.15’S, 179°10.57’E, 602 m, 1 spm ( NMNZ M.183839), BL 11.5 mm, 29.12.2003 .

Distribution. New Zealand (238–772 m: Dell 1956 and this study), Tonga (416–461: this study).

Remarks. Specimens from Tonga and New Zealand are very similar to the holotype (NMNZ M972) in shape and structure of the shell. Dorsal scales have grooves near the edge of the distal part. Aspecimen (NMNZ M.319774) from New Zealand (BL 18 mm) has a dorsal elevation of 0.27, slit formula 12/1/sinus + 8 obsolete, 18 gills on each side, and the nephridiopore and gonopore arranged between 4–5 and 5–6 gills accordingly counted from the last one. Aspecimen (MNHN-IM-2013-59983) from Tonga (BL 11 mm) has dorsal elevation of 0.31, slit formula 14/1 (rare 2)/sinus + 5 obsolete (valve II has two slits in one side), 16 gills in each side extending from valve IV to valve VII, nephridiopore and gonopore arranged between 4–5 and 5–6 gills accordingly counted from the last one, and a radula 1.6 mm long with 38 transverse rows of mature teeth.

L. profundior is very similar to L. scissurata , but differs from the latter in having grooves on the dorsal scales near the edge of the distal part (vs pits on the dorsal scales in L. scissurata ) and a shorter postmucronal area.

L. profundior differs from L. eernissei in having grooves on the dorsal scales near the edge of the distal part (vs smooth dorsal scales in L. eernissei )

Figures

FIGURE 1. Complete specimens of selected species of the genus Loricella. A, B. L. neoguinensis n. sp. Papua New Guinea, holotype (MNHN-IM-2013-45614), BL 16.0 mm; C, D. L. profundior, Tonga Islands, (MNHN-IM-2013-59980), BL 11.5 mm; E-G. L. vanbellei, New Caledonia, (MNHN-IM-2013-69525) BL 16.0 mm; A, C, G. Dorsal view; B, E. Ventral view; D, F. Lateral view. m.f.—mantle fold.

FIGURE 2. Loricella profundior, New Zealand, southern Kermadec Ridge, (NMNZ M.319774), BL 18.0 mm. A. Valve VII, dorsal view; B. Valve VIII, dorsal view; C. Valve VII, rostral view; D. Valve VII, detail of tegmentum in central and lateral areas; E. Valve VIII, lateral view.

FIGURE 3. Loricella profundior, New Zealand, southern Kermadec Ridge, (NMNZ M.319774), BL 18.0 mm. A. Dorsal and ventral scales; B, D. Dorsal scales; C. Dorsal scales and marginal spicules.

FIGURE 4. Loricella profundior, New Zealand, southern Kermadec Ridge, (NMNZ M.319774), BL 18.0 mm. A. Dorsal scales, marginal spicules and ventral scales on edge of caudal incision; B. Part of radula; C. Dorsal scales and bristles; D. Central, first lateral and major lateral teeth of radula.

FIGURE 5. Loricella profundior, Tonga Islands, (MNHN-IM-2013-59983), BL 11.0 mm. A. Valve I, dorsal view; B. Valve V, dorsal view; C. Valve VIII, dorsal view; D. Valve IV, ventral view; E. Valve V, detail of tegmentum in central and lateral areas; F. Valve V, rostral view; G. Valve VIII, lateral view.

FIGURE 6. Loricella profundior, Tonga Islands, (MNHN-IM-2013-59983), BL 11.0 mm. A. Dorsal and ventral scales; B. Dorsal scales and marginal spicules; C. Dorsal scales; D. Ventral scales.

FIGURE 7. Loricella profundior, Tonga Islands, (MNHN-IM-2013-59983), BL 11.0 mm. A. Dorsal scales and marginal spicules; B. Part of radula; C. Insertion plate, ventral view; D. Insertion plate, lateral view.