Deskripsieng
Description. Based on young specimen (BL 35. 0 mm, ZIN 2449): Anterior five valves in contact, remaining valves separated from each other. Color of tegmentum white or light gray, with brownish tint on pleurolateral area in valves II and III, fine dark brownish streaks on pleurolateral area and dark brownish jugum on valves V and VI. Girdle white in anterior half, yellowish buff in posterior half, with dark brownish transverse bands in the middle part. Ventral side of girdle uniformly light gray. Head valve elongate semicircular, longer than wide, sculptured with elongate pustules. Pustules are irregularly fused with neighboring ones, which are more frequently fused towards the margin of the tegmentum, forming almost flat surface. Valve II oval, widest among all valves. Valve III – VIII narrow, spindle-shaped, of which valve IV is the longest and valves VII and VIII are the shortest. Jugum smooth, wedge-shaped in valves II and III, very narrow and parallel sided in remaining valves. Pleurolateral area sculptured with 5 – 6 longitudinal, slightly radiated ribs formed by coalescence of pustules. In larger specimens, outer longitudinal ribs of valves II – VIII extending commarginally into jugal area, which interrupt inner ribs and even the jugum. Those longitudinal and commarginal ribs often obsolete in the anterior portion of valves (Fig. 1 D). Tail valve with terminal mucro overhanging on very short post-mucronal area where is sculptured with small pustules. Each pustule with 1 – 2 macraesthetes on top. Micraesthetes sparsely distributed along inner basal portion of ribs and prepustular area of pustules; no micraesthete on top of pustules (Figure 3 I). Articulamentum of valves II – VIII extending outward only in anterior half of tegmentum in dorsal view. Insertion plates of head valve long, but slightly shorter than half length of tegmentum. Slit formula 3 / 0 / 0. Color of articulamentum white with cherry under jugum. Girdle rather wide, fleshy. Dorsal side of girdle beset with minute slightly curved, strongly ribbed (8 – 9 double ribs often on one side) spicules, up to 100 μm x 50 μm, intermingling with large rounded or sometimes weakly flattened, smooth but occasionally striated spicules, attaining 250 μm x 100 μm. Sutural tufts of up to 7 slightly curved, smooth, blunt tipped needles, up to 500 μm x 60 μm. Marginal needles similar to those of sutural tufts, but often with several fine grooves, up to 500 μm x 62 μm. Ventral spicules flat, smooth, up to 100 μm x 24 μm. Gills extending from beginning of valve VI to valve VIII, composed of 31 ctenidia on each side. Radula 9.0 mm long with 47 transverse rows of mature teeth. Central tooth small, thick, concave at dorsal two third, keeled at ventral one third, round at top. Centro-lateral (first lateral) tooth with small, cusp at nodulous antero-dorsal corner. Major lateral (second lateral) tooth with large, thick tricuspid head; denticles blunt at tip and about equal length with transverse angular lines on proximal portion. Major uncinal tooth narrow with round tip, weakly keeled on posterior surface.
Sumber: Chitons of the genus Cryptoplax (Mollusca: Polyplacophora) from the Spratly Islands, South China Sea
Distribusieng
Distribution. C. larvaeformis has been recorded from a wide area in the tropical West Pacific, but we have not verified many of those records. At least the following records can be accepted: Tongatapu (Tongatabu), Tonga Islands (Rochebrune 1884, as C. coronatus); Bulia, Cicia, Kandav, Tuvutha, Viti, and Yaukuve Leve Islands, Fiji (Haddon, 1886; Pilsbry 1893; Schwabe et al. 2008); Pombo Island, Ambon, Indonesia (Slieker 2000); Woka Island, Indonesia (Schwabe 2007); Banacon Island, Bohol, the Philippines (Granpoder et al. 2023); “ the Philippines ” (Ang 1967); Spratly Islands, South China Sea (present study). Phi Phi Don Island, Phuket, Thailand (Granpoder et al. 2023). Record from Okinawa, Japan (Saito 2000) is an error caused by misidentifying C. oculata as C. larvaeformis (see below in remarks). In the Spratly Islands, the living animals were found at a depth of 1 – 20 m.
Sumber: Chitons of the genus Cryptoplax (Mollusca: Polyplacophora) from the Spratly Islands, South China Sea
Deskripsieng
Chiton eruciformis Sowerby 1822: pl. 139, fig. 5 [nomen nudum]. Chiton chitonellus de Blainville 1825: 550; Haddon 1886: 37; Kaas & Van Belle 1998: 45; Slieker 2000: 141; Gowlett- Holmes 2001: 46. Chiton vermiformis de Blainville 1825: 553 (de Blainville wrote, that he saw two specimens in the NHM, but the first author failed in finding them, type locality:? New Holland [= Australia]); Haddon 1886: 37; Pilsbry 1893: 57; Iredale & Hull 1925: 102; Kaas & Van Belle 1980: 139; 1998: 197; Slieker 2000: 154; Gowlett-Holmes 2001: 46. Chiton fasciatus Quoy & Gaimard 1835 (non Wood, 1815): 408, pl. 73, figs 21 – 29 (syntype MNHN lost, type locality: Polynesia: Tonga: Ha`apai group [19 ° 48 ’ S 174 ° 21 ’ W]: Pangai-Modou reef); Berge 1847: 113, pl. 20, fig. 6; Kaas & Van Belle 1980: 46; 1998: 71; Slieker 2000: 143; Gowlett-Holmes 2001: 46. Chitonellus fasciatus; Reeve 1847: pl. 1, fig. & spec. 2 a – b; Dall 1879: 299; van Bemmelen 1882: 95; 1883 a: 1; Tryon 1883: 346, pl. 85, fig. 95; Haddon 1886: 36 – 38, 41, 48; Thiele 1893: 400, pl. 32, fig. 35; Plate 1897: 270; von Martens 1889: 199; Clessin 1904: 124, pl. 38, figs 1 – 2. Chiton (Chitonellus) fasciatus; Chenu 1859: 384, fig. 2891; E. A. Smith 1884: 86. Chiton (Chitonellus) larvaeformis; Chenu 1859: 384, fig. 2890; E. A. Smith 1884: 85. Cryptoplax fasciatus; Brazier 1877: 75; Fischer 1887: 883.? Cryptoplax montanoi de Rochebrune 1882: 190 (one syntype MNHN 6066, Philippines: Sulu Islands [05 ° 20 ’ N 120 ° 22 ’ E]); Haddon 1886: 44; Pilsbry 1893: 58; Thiele 1909 a: 9, 52; Ashby 1922 a: 576, 1923 b: 241; Iredale & Hull 1925: 102; Kaas & Van Belle 1980: 87; 1998: 126; Slieker 2000: 148; Gowlett-Holmes 2001: 47; Schwabe 2007: 153. Cryptoplax peroni de Rochebrune 1882: 193 (holotype MNHN 5985, type locality: “ Nouvelle Holland ” [= Australia], based on one of the syntypes of Chitonellus laevis Lamarck, 1819); Haddon 1886: 44; Pilsbry 1893: 58; Thiele 1909 a: 52, 56; Lamy 1923: 260; Iredale & Hull 1925: 102; Taki & Taki 1930: 105; Kaas & Van Belle 1980: 98; 1998: 142; Slieker 2000: 149; Gowlett-Holmes 2001: 47. Cryptoplax (Chitonellus) fasciatus; de Rochebrune 1883: 33. Chiton (Chitonellus) eruciformis; E. A. Smith 1884: 86; Haddon 1886: 36. Chiton (Chitonellus) laevis; E. A. Smith 1884: 86. Cryptoplax coronatus de Rochebrune 1884 b: 238 (two syntypes at MNHN 6180, type locality: Polynesia: Tonga [19 ° 20 ’ S 174 ° 23 ’ W]); Thiele 1909 a: 54; Kaas & Van Belle 1980: 32; 1998: 52; Slieker 2000: 142; Gowlett-Holmes 2001: 47. Cryptoplax larvaeformis; Haddon 1886: 37, pl. 3, figs 12 a – 12 m; Pilsbry 1893 – 94: 56 (1893), pl. 11, figs 31 – 36, 40 – 43 (1894); 1901 a: 152, 154, pl. 14, figs 12 – 16; 1901 b: 204; von Martens 1894: 92; Wettstein 1904: 473 – 504, pls 10 – 12; Nierstrasz 1905 a: 73, pl. 6, figs 154 – 158; 1905 b: 150; Horst & Schepman 1908: 523; Thiele 1909 a: 54 (partim); 1931: 15; Iredale & Hull 1925: 101, pl. 12, figs 5, 10, 17, 25, 28, 35; 1927: 91, pl. 11, figs 5, 10, 17, 25, 28, 35; Ashby 1928: 167; Mackay 1930: 295; Taki & Taki 1930: 103; Bergenhayn 1930 b: 38, pl. 10, figs 91 – 93; Leloup 1933: 30; 1940: 25, pl. 3, fig. 1, text fig. 8; 1949: 8, 9, fig. 3 C; 1952: 53; Risbec 1946: 130, 134 – 144, figs 3 – 6; A. G. Smith 1960: 170, fig 44 1 a – f; Kuroda 1960: 1; Fischer-Piette & Franc 1960: 1718, 1738, 1748, 1754, 1756, 1760, 1761, 1764, 1766, fig. 1556 A; Ang 1967: 393, 423, pl. 16, figs 1 – 4; Kaas & Van Belle 1980: 72; 1998: 106; Van Belle 1983: 136, pl. 12, fig. 4; Zeidler & Gowlett 1986: 113; Saito 1994: 144; Littler, Littler & Taylor 1995: 1679; Gowlett-Holmes 2001: 46; Higo et al. 1999: 31; Littler & Littler 1999: 158, text fig; Anonymous 2000: 172, text fig; Slieker 2000: 22, 54, pl. 15, figs 12 – 12 a; Subba Rao & Dey 2000: 5; Wells 2000: 94; Schwabe 2001: 27; 2005 a: 54, pl. 2, fig. 11; 2006 b: 20; Saito 2001: 23, pl. 11, fig. 3; Xiutong 2004: 4, pl. 2 fig. A; Schwabe & Wanninger 2006: 218, fig. 18.1 C; Saito 2006 c: 131; Schwabe 2007: 149, figs 3, 4 A, C, 5 A, C, E, 6 A, C. Chitonellus rostratus (non of Reeve, 1847); Thiele 1893: 400, pl. 32, fig. 38. Chitonellus larvaeformis; Pelseneer 1898: 7, 22, 26, pl. 9, fig. 79; Clessin 1904: 123, pl. 40 (not 41 as reported by him), fig. 2. Cryptoplax lamarcki Thiele 1909 a [nomen nudum, a manuscript name of de Rochebrune, used for the second syntype of Chitonellus laevis Lamarck, 1819): 54; Lamy 1923: 261; Kaas & Van Belle 1980: 71; 1998: 105; Gowlett-Holmes 2001: 47. Cryptoplax laevis; Dupuis 1918: 529; Ashby 1923 b: 239. Cryptoplax (Chitonellus) larvaeformis; Ashby 1922 a: 576. Cryptoplax (Chitonellus) laevis; Ashby 1922 a: 577; 1926: 383. Cryptoplax (Chitonellus) lamarcki; Ashby 1922 a: 577. Cryptoplax laerviformis [sic]; Bergenhayn 1930 b: 54. Chiton cruciformis; Kaas & Van Belle 1980: 34; 1998: 56; Slieker 2000: 142; Gowlett-Holmes 2001: 46. Cryptochiton; Morton & Raj 1981: 84, pl. IV. 8. Cryptoconchus; Morton & Raj 1981: 86. Cryptoconchus [cf.] japonicus; Morton & Raj 1981: 108, pl. IV. 18. Chiton [sp.]; Abrea 1981: 9, figs 1 – 3. Cryptoplax [sp.]; Coleman 1981: 33 (upper picture). Locus typicus: Unknown. Primary type: Holotype (NHM 1951.1.28.1). Fiji records: Cryptochiton; Morton & Raj 1981: 84, pl. IV. 8. Cryptoconchus; Morton & Raj 1981: 86. Cryptoconchus japonicus (... or a related species); Morton & Raj 1981: 108, pl. IV. 18. Cryptoplax larvaeformis; Haddon 1886: 37, pl. 3, figs 12 a – m; Pilsbry 1893: 56, pl. 11, figs 31 – 34, 40 – 43; Littler & Littler 1999: 158.
Sumber: A checklist of Polyplacophora (Mollusca) from the Fiji islands
