Cryptoplax elioti Pilsbry, 1901

Schwabe, Enrico, Sirenko, Boris I. & Seeto, Johnson, 2008, A checklist of Polyplacophora (Mollusca) from the Fiji islands, Zootaxa 1777, pp. 1-52 : 27-28

Cryptoplax elioti Pilsbry, 1901

( Figures 6 C–E, 7B–D)

Cryptoplax elioti Pilsbry 1901a: 153 , pl. 14, figs 1–11; Nierstrasz 1906: 150; Thiele 1909a: 52, 53, 56; Taki & Taki 1930: 103; Bergenhayn 1930a: 21; 1930b: 38; 1933b: 160; Leloup 1940: 13, fig. 4; Hyman 1967: 71, figs 29D–E; Kaas & Van Belle 1980: 42; 1998: 66; Johnson 1982: 107; Kilias 1993: 418; Saito 1994: 144; Higo et al. 1999: 31; Schwabe 2001: 27; Saito 2001: 23, pl. 11, fig. 4; 2004: 98, 101, figs 16E–F.

Cryptoplax eleoti [sic]; Nierstrasz 1905a: 75, pl. 2, figs 29–30, pl. 6, figs 159–161; Tchang Shi et al. 1964: 7, fig; Xiutong 2004: 5; pl. 2, fig. B.

Cryptoplax evanescens Cooke 1913: 320 , text fig. (eight isolated valves of a syntype NHM 1929.10.28.3, two complete syntypes NHM 1929.10.28.1–2, type locality: Polynesia: Tuvalu: Funafuti Atoll [08°30’S 179°11’E] [on the label of syntype 1929.10.28.3 is written “Funafuti or Ellice Is.”]); Thiele 1929: 15, fig. 8; Taki & Taki 1930: 103; Leloup 1940: 14; Kaas & Van Belle 1980: 44; 1998: 69.

Cryptoplax jugosus Bergenhayn 1930a: 17 , pl. 1, figs 1–16 (lectotype SMNH 3750, type locality: Micronesia: Marshall Islands: Jaluit Atoll, S entrance, East beach [designated herein]; three paralectotypes SMNH 0 632, locality: Micronesia: Marshall Islands: Kiribati: Aranuka; one paralectotype SMNH 0 628, locality: Micronesia: Marshall Islands: Jaluit Atoll, lagoon, beach north of the station; three paralectotypes SMNH 0 632, locality: Micronesia: Marshall Islands: Kiribati: Aranuka; one paralectotype SMNH 0 629, locality: Micronesia: Marshall Islands: Jaluit Atoll, reef south west of South east entrance; one paralectotype SMNH 0 627, locality: Polynesia: Tuvalu: Nukufetau Atoll; one paralectotype SMNH 674, locality: Micronesia: Marshall Islands: Jaluit Atoll, near South entrance; one paralectotype SMNH 676, locality: Polynesia: Tuvalu: Nukufetau Atoll; one paralectotype SMNH 673, locality: Micronesia: Marshall Islands: Ebon, north west beach of lagoon; one paralectotype SMNH 675, locality: Micronesia: Marshall Islands: Jaluit Atoll, north of South entrance; three paralectotypes SMNH, locality: Micronesia: Marshall Islands: South entrance, east beach); 1930b: 38, pl. 10, figs 96–98; 1933a: 53; 1933b: 158; Leloup 1940: 14; Kaas & Van Belle 1980: 68; 1998: 101.

Cryptoplax larvaeformis (de Blainville MS, Burrow, 1815); Madrigal 1999: 42, fig.

Cryptoplax sp.; Risbec 1946: 151, pl. 2, figs 2–4.

Locus typicus: Samoa, Upolu Island, Apia [13°48’S 171°44’W].

Primary type: Holotype (ANSP 77308).

Material examined: ZSM Mol 20061619: 1 juvenile spm, Viti Levu, Laucala Bay, west side of the Nukumbutho channel of the fringing reef opposite the USP, 18°10.899'S 178°27.971'E, attached to a bottle, embedded in fine coral sand among dead coral blocs, strong currents, about 1 m, leg. Enrico Schwabe, 24 August 2006, wet; ZSM Mol 20061916: 1 juvenile spm, 2 adult spms, Viti Levu, Laucala Bay, reef flat opposite the Suva Harbour at the fringing reef, 18°10.434'S 178°24.987'E, at low tide, high amount of living corals, some sandy channels and patches, 1 m, under coral plates, leg. Enrico Schwabe & Michael Schrödl, 29 August 2006, wet; ZSM Mol 20061633: 1 adult spm, Viti Levu, Laucala Bay, North of Makuluva Island, 18°10.890'S 178°30.587'E, dead coral plateau with secondary coral growth, under a limestone, partly embedded in sand, surge exposed, 1–3 m, leg. Enrico Schwabe, 30 August 2006, wet; ZISP: 1 adult spm, Suva [18°08'S 178°25'E] coral reefs, leg. S. Stepanjants, 17 May 1966, wet.

Habitat: The species lives on the underside of coral boulders, slightly embedded in sand.

Distribution: The species is known from the Samoan Islands (type locality), the Marshall islands, Ellice and Kiribati (Bergenhay 1930, as Cryptoplax jugosus ), New Caledonia (Risbec 1946, as Cryptoplax sp.) Indonesia (Nierstrasz 1905a), Japan (Saito 2001), and the Chinese Sea (Xiutong 2004), the first author also examined a single wet preserved specimen from Queensland (NHM) (first record for Australia).

Remarks: This is the first record of this species from Fiji. To our knowledge for the first time a juvenile of this species is illustrated here ( Fig. 7 B). Clearly visible is that in juveniles, the valves are still in contact and are not covered by the perinotum. Although the intermediate valves of adults are hardly visible in ethanol preserved specimens, they are practically indiscernible in living specimens and the animal may easily be taken for a wormlike animal. In one of the collected specimens a gastropod that most probably belongs to the Capulidae is attached to the posterior perinotum region ( Figs 6 D–E). It is unknown, if the animal is parasitic or in any other way associated with the polyplacophoran.

The specimens of Cryptoplax jugosus come from different localities and in his original description Bergenhayn (1930a) did not choose a distinct specimen as holotype, so all the specimens have to be considered as syntypes. The label of sample number SMNH 3750 is marked to indicate it is the type. Thus we select herewith this specimen as the lectotype, leaving the others as paralectotypes. This makes “ Micronesia: Marshall Islands: Jaluit Atoll, S entrance, East beach” the type locality of C. jugosus .

Figures

FIGURE 6. A – B, Acanthopleura gemmata (de Blainville, 1825). A, the so called " tadruku " sold on the market in Suva. B, the species in a limestone in the intertidal zone in the Somosomo Strait of Vanua Levu (photo by Achim Nimmerfroh). C – E, Cryptoplax elioti Pilsbry, 1901, ZSM Mol 20061916: Fiji, Viti Levu, Laucala Bay, reef flat opposite the Suva Harbour at the fringing reef, 18 ° 10.434 ' S 178 ° 24.987 ' E, dorsal views of a living specimen. C, anterior part to show the head valve surrounding tuft pores. D, posterior portion with a sessil gastropod (arrow). E, detail view of the gastropod, which most probably belongs to the Capulidae. Scale unknown.

FIGURE 7. A, Onithochiton societatis Thiele, 1909, ZISP: Fiji, Cicia Island [17 ° 45 ’ S 179 ° 18 ’ W], Callisto St. 83, dorsal view. B – D, Cryptoplax elioti Pilsbry, 1901, dorsal views. B, ZSM Mol 20061619: Fiji, Viti Levu, Laucala Bay, west side of the Nukumbutho channel of the fringing reef opposite the USP, 18 ° 10.899 ' S 178 ° 27.971 ' E. C, ZSM Mol 20061916: Fiji, Viti Levu, Laucala Bay, reef flat opposite the Suva Harbour at the fringing reef, 18 ° 10.434 ' S 178 ° 24.987 ' E, anterior portion. D, same specimen as in fig. C, but posterior portion. E – F, Cryptoplax larvaeformis (de Blainville MS, Burrow, 1815), ZISP: Fiji, Cicia Island [17 ° 45 ’ S 179 ° 18 ’ W], Callisto St. 83. E, dorsal view of the anterior portion. F, dorsal view of the posterior portion. Scale bars 2 mm.