Lophoplax vermiculata (A. Milne-Edwards, 1873 )

Ng, Peter K. L. & Rahayu, Dwi Listyo, 2023, Review of the pilumnid crab genus Lophoplax Tesch, 1918 from the western Pacific, with descriptions of two new species, and the clarification of the identity of Pseudocryptocoeloma parvus Ward, 1936 (Crustacea: Brachyura), Zootaxa 5244 (5), pp. 428-454 : 437-441

publication ID	https://doi.org/ 10.11646/zootaxa.5244.5.2
publication LSID	lsid:zoobank.org:pub:B55396DA-15DB-4CDF-81FD-78686A0EC3A2
DOI	https://doi.org/10.5281/zenodo.7665797
persistent identifier	https://treatment.plazi.org/id/039087CD-7E0C-7325-47C6-FDDBF26AF810
treatment provided by	Plazi
scientific name	Lophoplax vermiculata (A. Milne-Edwards, 1873 )
status

Treatment

Lophoplax vermiculata (A. Milne-Edwards, 1873) View in CoL

( Figs. 1D–F View FIGURE 1 , 2E–G View FIGURE 2 , 4A–C View FIGURE 4 , 5D, E, J, K View FIGURE 5 , 6D, E View FIGURE 6 , 7D, E, J, K View FIGURE 7 , 8C View FIGURE 8 , 9F, G View FIGURE 9 , 11 View FIGURE 11 )

Pilumnus vermiculatus A. Milne-Edwards, 1873: 247 View in CoL , pl. 9 fig. 6; Miers 1886: 149; Kawamoto & Okuno 2003: 142; Marumura & Kosaka 2003: 57; Ng & Richer de Forges 2007: 327; Titelius et al. 2009: 154; Naruse 2010: 32.

Pilumnus (Parapilumnus) vermiculatus View in CoL — Kossmann 1877: 38.

Planopilumnus vermiculatus — Balss 1933: 13, 41; Balss 1938: 70; Miyake 1939: 218, 239; Garth 1964: 141; Serène 1968: 86; Sakai 1976: 303, 492, pl. 176 fig. 2; Miyake 1983: 233; Garth et al. 1987: 246, 259; Nagai & Nomura 1988: 191; Takeda 1989: 168, 179; Takeda 1994: 211; Nomura et al. 1996: 17; Fransen et al. 1997: 119; Davie & Short 2001: 83; Sakai 2003: 26.

Platypilumnus vermiculatus — Davie 2002: 419.

“ Pilumnus ” vermiculatus View in CoL — Ng et al. 2008: 142.

Lophoplax? sp. — Paulay et al. 2003: 501.

Vellumnus vermiculatus View in CoL — Ng 2010: 51; Hosie et al. 2015: 276; Fujita 2018: 90.

Type material. Lectotype: male (10.6 × 8.2 mm) ( ZRC 2022.696 View Materials ), under stones in middle of corals, New Caledonia, coll. M. Balansa, 1868–1872 . Paralectotypes: 3 dried females (1 ovigerous) ( MNHN B2848 View Materials ), New Caledonia, coll. M. Balansa , 1868–1872.

Other material examined. New Caledonia — 1 juvenile male (7.1 × 5.6 mm) ( UF 39041 ), rubble field, north tip of Huon Atoll , 17.91°S 162.90°E, 0–3 m, coll. N. Evans, 13 November 2013 GoogleMaps ; 1 male (13.9 × 11.0 mm) ( UF 39325 ), lagoon, intertidal area, rock rubble, Surprise Island , 18.49°S 163.10°E, 0–3 m, coll. N. Evans, 19 November 2013 GoogleMaps ; 1 female (17.3 × 12.9 mm) ( UF 39279 ), rubble field, north tip of Huon Atoll , 17.91°S 162.90°E, 0–3 m, coll. N. Evans, 14 November 2013 GoogleMaps . Guam — 1 subadult male (5.6 × 4.5 mm) ( ZRC 2013.1047 View Materials ), in rubble bed, ca. 3 m water, Pago Bay , coll. J. Starmer, 4 December 1998 ; 1 female (7.0 × 5.1 mm) ( UF 785 ), on wall, Tepungan Channel , 13.5°N 144.8°E, ca. 2 m, at night, coll. L. Kirkendale, 17 November 1998 GoogleMaps ; 1 male (14.1 × 10.8 mm) ( UF 388 ), forereef, under rubble in surge zone, Pago Bay , 13.5°N 144.8°E, 4–8 m, coll. G. Paulay, 14 August 2000 GoogleMaps . Saipan — 1 female (14.2 × 11.3 mm) ( UF 34958 ), Saipan Lagoon, North Marianas , 13.5°N 144.8°E, 3 m, coll. J. Starmer GoogleMaps , no date. Palau — 1 male (12.8 × 10.3 mm) ( UF 39950 ), back reefs, coral rubble and sand, near Uchelbelau Reef , 7.26°N 134.52°E, 0–1 m, coll. N. Evans & A. Catches, 29 May 2014 GoogleMaps . Pohnpei — 1 male (12.7 × 10.1 mm), 2 females (13.8 × 10.7 mm, 16.6 × 12.5 mm) ( UF 5873 ), channel with seagrass and coral, next to Japanese dock at clam hatchery, Lenger Island, Caroline Islands , 6.99°S 158.23°E, 0–1 m, coll. J. Starmer, 14 March 2003 GoogleMaps . Japan —1 young male (7.2 × 5.7 mm) ( ZRC 2013.169 View Materials ), Oura Village, Yawada, Okinawa Island , Ryukyu Islands , coll. T. Maenosono, 16 October 2008 ; 2 females (15.3 × 11.7 mm, 16.2 × 13.1 mm) ( ZRC 2022.776 View Materials ), Sesoko Island, Motobu Town, Okinawa Island Group , Ryukyu Islands , coll. T. Maenosono, 3 June 2020 ; 1 female (13.7 × 10.5 mm) ( ZRC 2022.775 View Materials ), Minatogawa, Urasoe City, Okinawa Island , Ryukyu Islands , coll. T. Maenosono, 4 January 2018 ; 2 males, 1 female ( RUMF-ZC 5206 ), Benoki, Kumigani, Okinawa Island , Ryukyu Islands , coll. T. Maenosono, 16 April 2010 .

Diagnosis. Carapace subquadrate ( Fig. 4A–C View FIGURE 4 ); epigastric, hepatic, cardiac and intestinal areolets prominent, distinctly rugose, pitted; epigastric areolets relatively wide, fused with protogastric areolets to varying degrees ( Fig. 4A–C View FIGURE 4 ); protogastric areolet relatively wide ( Fig. 4A–C View FIGURE 4 ); cardiac areolet transverse in position ( Fig. 4A–C View FIGURE 4 ); hepatic areolet prominent, proportionately long, reaching only to base of second anterolateral tooth ( Fig. 4A–C View FIGURE 4 ); external orbital tooth triangular with sharp tip, relatively wide ( Fig. 4A–C View FIGURE 4 ); tips of anterolateral teeth sharply pointed ( Fig. 4A–C View FIGURE 4 ); junction between antero- and posterolateral margins demarcated by sharp granules and/or rugosities ( Figs. 4A–C View FIGURE 4 ); epistome relatively wider longitudinally ( Fig. 5D, E View FIGURE 5 ); median lobe of posterior margin of the epistome broadly triangular, with lateral margins gently concave ( Fig. 5D, E View FIGURE 5 ). Third maxilliped with merus quadrate, ischium subrectangular ( Fig. 5J, K View FIGURE 5 ). Dorsal and lateral surfaces of cheliped carpus with 2 obvious rugose, pitted longitudinal swellings, rest of surface rugose, granulate ( Fig. 6D, E View FIGURE 6 ). Cheliped fingers not distinctly bent, pollex subparallel with ventral margin of palm ( Fig. 7D, E View FIGURE 7 ). P2–P5 relatively short in adults, longer in subadults ( Fig. 7J, K View FIGURE 7 ); outer surface of P3–P5 merus, carpus and propodus gently rugose, with low median longitudinal swelling ( Fig. 7J, K View FIGURE 7 ). Male pleonal somites 4–6 transversely wider ( Fig. 9F, G View FIGURE 9 ), telson wider than long, semicircular in shape ( Fig. 11A View FIGURE 11 ). G1 strongly sinuous, distal part relatively shorter, gently hooked to straight or gently upcurved ( Fig. 11B–D View FIGURE 11 ).

Colour in life. Carapace cream to white with symmetrical patches of magenta, red or orange on carapace, mostly on the gastric and branchial regions; pale magenta patches at joints of chelipeds and ambulatory legs ( Fig. 1D–F View FIGURE 1 ).

Remarks. Alphonse Milne-Edwards (1873: 247, pl. 9 fig. 6) described this species but he did not indicate how many specimens he had. Sakai (1976: 491) in his discussion on Planopilumnus minabensis Sakai, 1969 (at present in Vellumnus Ng, 2010 ), commented that “The holotype of this species was compared with that of P. vermiculatus by courtesy of FOREST and GUINOT at Museum National d’Histoire Naturelle, Paris.” This is not correct as no holotype was selected by A. Milne-Edwards (1873). Fransen et al. (1997: 119) noted that they had some 18 syntype specimens in the Naturalis (Leiden) exchanged from Paris. In the ZRC is an old uncatalogued specimen presumably from old exchanges that is labelled as a syntype of the species. To stabilise the taxonomy of this species, this male is here designated as the lectotype of Pilumnus vermiculatus A. Milne-Edwards, 1873 ( Figs. 2E View FIGURE 2 , 4A View FIGURE 4 , 11 View FIGURE 11 ).

In establishing Vellumnus, Ng (2010: 51) commented that “ Vellumnus vermiculatus is peculiar in that the carapace setae are longer and concentrated along the anterolateral and frontal regions, with the surfaces below relatively more swollen rather than ridge-like. The figures provided for Pilumnus vermiculatus by A. Milne-Edwards (1873: 247, pl. 9 fig. 6) are somewhat schematic and do not show all the features of the species well. The types of V. vermiculatus examined actually more closely resemble species of Heteropilumnus De Man, 1895 , and to some degree, Cryptocoeloma Miers, 1884 (see Ng 1987, 1989). For the moment, it is retained in Vellumnus as an atypical member of the genus.” A re-examination of the available material of V. vermiculatus now shows that it should instead be referred to Lophoplax . In the ZRC and UF are various specimens that had been identified by the first author as “ Lophoplax sp. ” (see Paulay et al. 2003); they are all L. vermiculata .

As with L. sordida n. sp., the setae on the carapace and pereopods of smaller specimens of L. vermiculata are finer, less dense and shorter than adults ( Figs. 2F View FIGURE 2 , 3B View FIGURE 3 ).

The Japanese specimens agree well with the material from Guam and New Caledonia in external morphology and we believe they are conspecific. The only difference is that the distal part of the G 1 in the type is gently curving downwards ( Fig. 11B–D View FIGURE 11 ) whereas Maenosono (2019: fig. 14O, P) depicted it as gently curving upwards. In the material we have from Japan and Guam, the G1s are mostly straight or almost so. Such variation has previously been reported for Heteropilumnus satriai Yeo, Rahayu & Ng, 2004 (cf. Ng et al. 2018: fig. 9A–C, E–G).

Habitat. The types were collected from among under rocks in intertidal coral reefs in New Caledonia. Specimens have also been collected from shallow subtidal waters by snorkelling or SCUBA, in reef habitats, rubble habitats, near seagrass beds, up to depths of 8 m.

Distribution. New Caledonia, Pohnpei, Palau, Guam, Marshall Islands, Ryukyu Islands ( Japan).