Platyozius laevis ( Borradaile, 1902 )

CASTRO, PETER & NG, PETER K. L., 2010, Revision of the family Euryplacidae Stimpson, 1871 (Crustacea: Decapoda: Brachyura: Goneplacoidea), Zootaxa 2375 (1), pp. 1-130 : 84-89

publication ID

https://doi.org/ 10.11646/zootaxa.2375.1.1

persistent identifier

https://treatment.plazi.org/id/03F487A8-390F-427C-7D8C-FB23F645F9D1

treatment provided by

Felipe

scientific name

Platyozius laevis ( Borradaile, 1902 )
status

 

Platyozius laevis ( Borradaile, 1902)

( Figs. 33A–F View FIGURE 33 ; 34A–F View FIGURE 34 ; 35A–G View FIGURE 35 ; 38A–C View FIGURE 38 )

Pseudozius (Platyozius) laevis Borradaile, 1902: 243 , fig. 45. — Garth 1971: 185 [in list].

Platyozius laevis — Rathbun 1906: 861, pl. 11, fig. 7 [Hawaiian Is.].

Eucrate sulcatifrons — Edmondson 1962: 4, figs. 1 b, 2a-c [Hawaiian Is.] — McLaughlin et al. 2005: 257 [in list]. [not Eucrate sulcatifrons ( Stimpson, 1858) = Eucrate crenata (De Haan, 1835) ]

Eucrate laevis — Dai et al. 1996: 247, fig. 10 [South China Sea]. — Ng et al. 2008: 78 [in list]. — Yang et al. 2008: 770 [in list] [ China].

Eucrate sp. — Kawamoto & Okuno 2003: 149 [colour photograph] [ Japan].

Type material. Male holotype, 5.0 mm × 6.0 mm ( UMZC) ( Fig. 34A View FIGURE 34 ) ; 1 female, 7.5 mm × 9.5, 1 male, 7.0 mm × 8.5 mm ( UMZC) not mentioned in the description .

Type locality. Maldives, Suvadiva Atoll , 36 m.

Material examined. Madagascar. North of Nosy Be , 12°26’N, 48°16’E, 200 m, G. Casellato coll., 10.1971: 1 male ( MNHN-B30524 ) GoogleMaps .

Seychelles. REVES 2: stn.18, 05.09.1980: 1 female, 4.4 mm × 4.8 mm ( MNHN-B30539 ) ; stn. 32, 57 m, 09.09.1980: 1 female, 4.2 mm × 4.3 mm ( MNHN-B30535 ) ; stn. 51, 42 m, coral and sand, 15.09.1980: 1 male 6.4 mm × 7.7 mm, 1 female, 5.3 mm × 6.2 mm ( MNHN-B30537 ) ; stn. 60, 41 m, 19.09.1960: 1 male, 6.0 mm × 7.5 mm, 4 pre-adults females, 6.3 mm × 7.7 mm, 6.4 mm × 7.7 mm, 6.0 mm × 7.2 mm, cw 7.8 mm, 1 preadult 4.5 mm × 5.2 mm ( MNHN-B30534 ) .

Maldives. Suvadiva Atoll , 36 m.: male holotype, 5.0 mm × 6.0 mm; same location: 1 female, 7.5 mm × 9.5, 1 male, 7.0 mm × 8.5 mm ( UMZC). – Laamu Atoll, under boulders in reef, A. Anand J. K. coll., 1 male, 6.1 mm × 7.8 mm ( ZRC 2007.0707 View Materials ) .

Japan. Ogasawara Is., off Chichi-jima I., 27°06.35’N, 142°10.48’E, 59– 55 m, coral sand and rock, TRV Shin’yo-maru, 1997 cruise, stn. 10, T. Komai coll.: 2 males, 5.0 mm × 5.6 mm, 4.6 mm × 5.2 mm ( CBMZC 6531 ) GoogleMaps .

Hong Kong. No data: 1 female ( SWIMS SML-Z-159.1 ) .

Philippines. Sulu Archipelago , Basilan Straits, SW Malanipa I., 48–51 m, Pele, B. R. Wilson coll., 12.02.1964: 1 male, 5.4 mm × 7.0 mm ( MNHN-B10342 ) .

Bohol, Panglao I., Balicasag I., tangle nets of local fishermen, 12.2003: 1 female, 11.0 mm × 14.0 mm ( ZRC 2004.0806 View Materials ); 02.05.2004 : 1 female, 9.5 mm × 11.9 mm ( ZRC 2004.0732 View Materials ) .

Indonesia. Ceram , Mariel King Memorial Expedition: stn. CP I, haul 1, Piru Bay, 03°15’S, 128°8’E, 59– 64 m, 01.06.1970: 1 male, 4.5 mm × 4.8 mm ( MNHN-B30773 ); stn. CP III, 01.06.1970: 1 male, 5.7 mm × 6.6 mm ( MNHN-B30774 ) GoogleMaps .

Kai Is., Mariel King Memorial Expedition: stn. KR VI, haul 3–10, north of Du Rowa I., 05°32’S, 132°41’E, 27–37 m, 11.06.1970: 1 female, 5.1 mm × 6.3 mm ( MNHN-B30840 ) GoogleMaps .

Solomon Is. SALOMON 1: stn. DW 1822, 09°51.8’S, 160°51.8’E, 51–54 m: 1 male, 4.2 mm × 4.7 mm ( MNHN-B30777 ); 1 male, 4.6 mm × 4.8 mm ( MNHN-B32011 ) GoogleMaps .

Vanuatu. SANTO 2006: stn. DB29, west of Malo I., 15°38.9’S, 167°05.1’E, 15 m, 17.09.2006: 1 male, 6.9 mm × 8.5 mm ( ZRC) GoogleMaps .

Australia. Queensland, Wreck Reef near Porpoise Cay , 22°11’S, 155°20’E, outer reef flat under dead coral boulders at base of live coral heads, low tide, J. Short & S. Mullens coll., 14.05.1988: 1 female, 12.3 mm × 15.0 mm ( QM W15174 View Materials ) GoogleMaps . – Flinders Reef, off Cape Moreton , 26°59’S, 155°29’E, fringing reef under rock, scuba, 20 m, N. Coleman coll., 09.07.1997: 1 male, 10.9 mm × 13.5 mm ( QM W24144 View Materials ) GoogleMaps .

Chesterfield Is. CORAIL 2: stn.DW1, 20°55.9’S, 161°40.7’E, 59 m, 20.07.1988: 1 female, 6.5 mm × 7.7 mm ( MNHN-B30801 ). – Stn. DW 11, 20°59’S, 161°41’E, 58 m, 20.07.1988: 1 male, 5.5 mm × 6.9 mm ( MNHN-B30779 ) GoogleMaps .

New Caledonia. LAGON: stn. 229, Ile Ouen, Baie du Prony, 22°39’S, 166°39’E, 41 m: 1 male, 6.6 mm × 8.0 mm ( MNHN-B30778 ) GoogleMaps .

LAGON EST: stn. 748, 21°16.9’S, 165°49.9’E, 35 m, 06.01.1987: 1 pre-adult female, 6.1 mm × 7.4 mm, photograph CB 392 ( MNHN-B30782 ) GoogleMaps .

MUSORSTOM 5: stn. DW 264, 25°19.69’S, 159°44.33’E, 56 m, 08.10.1986: 1 male, 7.0 mm × 8.5 mm, photograph ( MNHN-B30780 ) GoogleMaps

NORFOLK 2: stn. DW 2135, 23°02’S, 168°21’E, 295–330 m, 03.11.2003: 1 female, 5.4 mm × 6.7 mm ( MNHN-B30781 ) GoogleMaps .

Loyalty Is. Ouvéa I., Mouli, diving, 11 m, J.-P. Menou coll., 13.11.1991: 1 male, 10.1 mm × 12.5 mm, photograph CB 1070 ( MNHN-B30608 ) .

Micronesia. Yap I., Y–251, R. Hiatt coll., 1952: 1 male, 8.5 mm × 10.7 mm ( MNHN-B24496 ) .

Marshall Is. Enewetak Atoll, #090351-B: 1 male, 1 pre-adult female, 1 female ( LACM) .

Hawaiian Is. Northwest Hawaiian Is, French Frigate Shoals, stn. FFS 114, 23.699°N, 166.058°W, fore reef, 16.8 m, G. Paulay et al. coll., 19.10.2006: 1 male, photograph 1JMO166, 6.9 mm × 8.6 mm ( LACM) GoogleMaps ; 23.699°N, 166.0575°W, under coral rubble, 16.7 m: 1 male, photograph, 5.0 mm × 6.5 mm ( UF 12194 ) GoogleMaps . – Stn FFS 192, 23.699°N, 166.058°W, fore reef, under coral rubble, 25.7 m, G. Paulay et al. coll., 26.10.2006: 1 male, photograph, 7.7 mm × 9.7 mm ( UF 12283 ) GoogleMaps ; 23.8633°N, 166.1877°W: 1 male, photograph, 4.4 mm × 4.9 mm ( UF 12284 ) GoogleMaps . – Stn FFS 193, 23.8445°N, 166.3348°W, back reef, under coral rubble, 18.1 m, G. Paulay et al. coll., 26.10.2006: 1 male, photograph, 13.5 mm × 10.4 mm ( UF 12282 ) GoogleMaps .

Oahu, Halona Blowhole, 17 m, 21°26’N, 157°58’W, under surface of rubble, R. Holcom coll., 2.08.1997: 1 male, 7.7 mm × 9.5 mm (QM W28380 View Materials ) GoogleMaps .

French Polynesia. Tuamotu Archipelago , Rangiroa Atoll , ca. 1 km S of NW point of atoll off Motu Maeherahonae, stn. BRNG–31, 14°55.72’S, 147°51.47’W, reef flat, under coral rubble, Liu et al. coll., 13.10.2001: 2 females, 9.5 mm × 12.1 mm, 12.5 mm × 16.0 mm, photographs GP909: 5–7 and 912: 9–11 ( UF 1534 ) GoogleMaps .

Society Is., Moorea , offshore between Motu Tiahura and Fareone, outer reef slope, 17.4848°N, 149.9172°W, S. McKeon et al. coll., 14.10.2008: 1 ovigerous female, 7.8 mm × 9.4 mm ( UF 15510 ) GoogleMaps .

Diagnosis. Anterolateral borders of carapace each with three short, triangular teeth ( Figs. 33A–E View FIGURE 33 ; 34 View FIGURE 34 ); postorbital ridge along entire anterior portion of carapace ( Fig. 34E View FIGURE 34 ); obtuse outer orbital angle ( Figs. 34 View FIGURE 34 ; 35A–C View FIGURE 35 ). Dorsal surface of carapace with brightly coloured pattern of irregular lines ( Fig. 33 View FIGURE 33 ).

Remarks. Unique among euryplacids is a postorbital ridge that curves along the entire anterior portion of the carapace between the second anterolateral teeth and parallel to the front and orbits of Platyozius . In small individuals (e.g. male, 5.5 mm × 6.9 mm, MNHN-B30779; male, 7.0 mm × 8.5 mm MNHN-B30780; female, 5.4 mm × 6.7 mm, MNHN-B30781) the ridge, as well as the third anterolateral teeth, are only slightly evident.

Also diagnostic is the unique colour pattern ( Fig. 33 View FIGURE 33 ). The details of the colour pattern (see below) vary, even among specimens collected from the same locality. This relative variation is not correlated with any morphological differences suggesting that these differences are not species specific.

Other details of the morphology of the species are given in the diagnosis of Platyozius (see above) and in Table 1.

Platyiozius laevis shows a very wide geographical distribution across the Indo-West Pacific , wider than any known euryplacid. It has been collected from under coral rubble or rocks at low tide in the Maldives, Australia, the Hawaiian Islands, and French Polynesia as well as dredged in water as deep as 200 m.

Colour pattern. The colourful pattern diagnostic of P. laevis rapidly disappears in alcohol-preserved specimens. It is still discernible in a photograph of a specimen from the Hawaiian Is. given by Rathbun (1906: pl. 11, fig. 7). A colour photograph of a specimen from the type locality, the Maldives (male, 6.1 mm × 7.8 mm; ZRC 2007.0707), shows irregular, red-brown spots and wavy lines across the carapace, an almost continuous, wavy, thin, red-brown band around the anterior and lateral borders of the carapace, and a large irregular spot of the same red-brown colour on the gastric region. There are three red-brown bands across each of the ambulatory legs and one on dactylus of the chelipeds. All carapace and pereopod markings are on a light pink background, except on the anterior half of the carapace, which is yellowish orange. A colour photograph of a specimen from the Ryukyu Is., Japan ( Kawamoto & Okuno 2003: 149, as Eucrate sp. ) shows an almost identical colour pattern to that of the Maldives specimen. There are variations of this colour pattern, however. A specimen from New Caledonia (male, 7.0 mm × 8.5 mm; MNHN-B30780) shows the dark red-brown pattern across the anterior and anterolateral portions of the carapace and a cross-like pattern along the front, bound by two pink circles. The rest of the carapace and the pereopods are pink, with red-brown bands on the ambulatory legs. The colour pattern of two females from French Polynesia (9.5 mm × 12.1 mm, 12.5 mm × 16.0 mm; UF 1534; Fig. 33A, B View FIGURE 33 ) is similar to that of the New Caledonia male except that the red-brown markings on the carapace show slightly different patterns, the carapace having an orange background except six greyish spots, the bands on the ambulatory legs thicker and four in number, and there are irregular spots on each of the chelipeds. Specimens from the Northwest Hawaiian Islands ( Fig. 33C, E, F View FIGURE 33 ) and Vanuatu ( Fig. 33D View FIGURE 33 ) show an orange or white carapace background and variations in the spotting of the chelipeds and banding of the ambulatory legs.

Distribution. Wide distribution across the Indo-West Pacific region: Indian Ocean from Madagascar, Seychelles, the Maldives, and India (unpublished manuscript by M. Deb, Zoological Survey of India); western Pacific from southern Japan to Indonesia (photographic evidence from Sulawesi), New Caledonia, and Queensland, Australia; Micronesia, Marshall Is., Hawaiian Is., and French Polynesia. Depth: intertidal to 200 m.

Genus Psopheticoides Sakai, 1969

Psopheticoides Sakai, 1969: 272 ; 1976: 523 [in key], 528. — Serène & Vadon 1981: 127 [discussion]. - Karasawa & Kato 2003a: 151 [in list]; 2003b: 139 [in list]. — Castro 2007: 618, 620 [discussion]. — Ng & Castro 2007: 44 [in list]. — Ng et al. 2008: 78, 79 [in list]. — De Grave et al. 2009: 33 [in list].

Diagnosis. Carapace ( Figs. 36A View FIGURE 36 ; 39C View FIGURE 39 ) trapezoidal, almost as wide as long, dorsal surface smooth without clear indication of regions, large orange-red, circle on cardiac region (remains visible in preserved specimens); anterolateral borders arched; front wide, straight with small median notch (absent in large individuals), transverse sulcus along margin. Two teeth posterior to triangular outer orbital angle, first short, elongated with rounded outline following arched anterolateral border, second acute, dorsally salient. Orbits long, wide, spherical ( Fig. 36B View FIGURE 36 ), 2 weak notches on supraorbital border, raised lobe immediately before inner notch; small, low inner suborbital tooth on broad, suborbital border ( Fig. 36C View FIGURE 36 ); eye peduncles short, large reniform (dorsoventrally flattened) corneas ( Fig. 36B, C View FIGURE 36 ). Basal antennal article slightly mobile, completely closing orbital hiatus so that antennal flagellum is excluded from orbit ( Fig. 36B, C View FIGURE 36 ). Anteroexternal margin of third maxilliped merus auriculiform ( Fig. 36C View FIGURE 36 ). Cheliped fingers ( Fig. 36D View FIGURE 36 ) stout, slightly longer than swollen propodus, light in colour; carpus with tooth on inner margin, merus with acute anterodorsal tooth; row of short setae along anterior margin of carpus. Dorsal margins of ambulatory legs (P2–P5) meri, carpi, propodi unarmed, dactyli slender, smooth, setose; P5 propodus, dactylus proportionally short, flattened ( Fig. 36A View FIGURE 36 ), fringed with many short setae. Thoracic sternum ( Fig. 36E, G View FIGURE 36 ) wide; thoracic suture 2/3 complete, straight ( Fig. 36E View FIGURE 36 ); 3/4 deep, short, interrupted; 4/5, 6/7, 7/8 interrupted, 5/6 complete ( Fig. 36G View FIGURE 36 ); median groove on thoracic sternites 7, 8. Sterno-abdominal cavity of male deep, nearly reaching anterior margin of sternite 4 ( Fig. 36E View FIGURE 36 ). Press-button of male abdominal-locking mechanism as large tubercle near thoracic suture 4/5 (presence in pre-adult females unknown). Male abdomen narrow, slender (T-shaped), lateral margins of somites 4–6 abruptly narrowing from somite 3 to transversely narrow, pointed telson ( Fig. 36E View FIGURE 36 ); somite 3 reaching inner margins of P5 coxae; no portions of thoracic sternite 8 exposed by closed abdomen, somite 2 transversely slightly shorter than somite 3 ( Fig. 36F View FIGURE 36 ), somite 1 conspicuous. G1 long, slender, slightly sinuous, arrowhead-shaped apex, relatively large denticles ( Fig. 38D, E View FIGURE 38 ); G2 less than one-third of G1, straight, apex with 2 processes: one long, tip obtuse; second much shorter, tip obtuse ( Fig. 38F View FIGURE 38 ). Male genital opening (gonopore) coxal; coxosternal disposition of long penis with greatly expanded proximal portion, protected by concave posterior portion of thoracic sternite 7. Vulva crescent shaped, extending across anterior, median portion of sternite 6 close to median axis of thorax ( Fig. 36G View FIGURE 36 ); thick, transverse, ventrally projecting sternal vulvar cover on outer margin in large females ( Fig. 36G View FIGURE 36 ).

Type species. Psopheticoides sanguineus Sakai, 1969 (by original designation, gender masculine).

Remarks. The inclusion of the genus in the subfamily Euryplacinae of the Goneplacidae was first suggested (conduisent à l’inclure) by Serène & Vadon (1981: 127), although Sakai (1969: 272) had noted the similarities in the male abdomen and gonopods of his new species with those of Eucrate . Karasawa & Kato (2003a: 151; 2003b: 139) formally included Psopheticoides in the Euryplacinae and ultimately in the Euryplacidae ( Castro 2007: 618, 620; Ng et al. 2008: 78, 79).

Unusual among euryplacids are the dorsoventrally flattened reniform eyes in this species ( Fig. 36B View FIGURE 36 ), a character also found in Frevillea ( Figs. 18E, F View FIGURE 18 ; 19A, B View FIGURE 19 ) and in some members of the Goneplacidae ( Castro 2007) . The G1 is unusual in featuring an arrowhead-shaped apex ( Fig. 38D, E View FIGURE 38 ; Sakai 1969: fig. 17a, a’). Also unusual among euryplacids is the presence of a fully sclerotised sternal vulvar cover ( Fig. 36G View FIGURE 36 ). Psopheticoides shares such a structure with only one euryplacid genus, Trissoplax n. gen. ( Fig. 41G View FIGURE 41 ). The typical euryplacid vulva has simple margins and the opening itself is covered by a soft membrane (e.g. Figs. 3G View FIGURE 3 , 19H View FIGURE 19 ). The role of such a sclerotised vulvar cover, in goneplacoids remains unknown (see Castro 2007: 755).

Species included. Psopheticoides sanguineus Sakai, 1969 The genus is restricted to the Indo-West Pacific region.

ZRC

Zoological Reference Collection, National University of Singapore

QM

Queensland Museum

LACM

Natural History Museum of Los Angeles County

Kingdom

Animalia

Phylum

Arthropoda

Class

Malacostraca

Order

Decapoda

Family

Euryplacidae

Genus

Platyozius

Loc

Platyozius laevis ( Borradaile, 1902 )

CASTRO, PETER & NG, PETER K. L. 2010
2010
Loc

Eucrate sp.

Kawamoto, T. & Okuno, J. 2003: 149
2003
Loc

Eucrate laevis

Ng, P. K. L. & Guinot, D. & Davie, P. 2008: 78
Yang, S. & Chen, H. & Jiang, W. 2008: 770
Dai, A & Cai, Y. & Yang, S. 1996: 247
1996
Loc

Psopheticoides

De Grave, S. & Pentcheff, N. D. & Ahyong, S. T. & Chan, T-Y & Crandall, K. A. & Dworschak, P. C. & Felder, D. L. & Feldmann, R. M. & Fransen, C. H. J. M. & Goulding, L. Y. D. & Lemaitre, R. & Low, M. E. Y. & Martin, J. W. & Ng, P. K. L. & Schweitzer, C. E. & Tan, S. H. & Tshudy, D. & Wetzer, R. 2009: 33
Ng, P. K. L. & Guinot, D. & Davie, P. 2008: 78
Castro, P. 2007: 618
Ng, P. K. L. & Castro, P. 2007: 44
Karasawa, H. & Kato, H. 2003: 151
Serene, R. & Vadon, C. 1981: 127
Sakai, T. 1976: 523
Sakai, T. 1969: 272
1969
Loc

Eucrate sulcatifrons

McLaughlin, P. A. & Camp, D. K. & Angel, M. V. & Bousfield, E. L. & Brunel, P. & Brusca, R. C. & Cadien, D. & Cohen, A. C. & Conlan, K. & Eldredge, L. G. & Felder, D. L. & Goy, J. W. & Haney, T. & Hann, B. & Heard, R. W. & Hendrickx, E. A. & Hobbs, H. H. & Holsinger, J. R. & Kensley, B. & Laubitz, D. R. & LeCroy, S. E. & Lemaitre, R. & Maddocks, R. F. & Martin, J. W. & Nikkelsen, P. & Nelson, E. & Newman, W. A. & Overstreet, R. M. & Poly, W. J. & Price, W. W. & Reid, J. W. & Robertson, A. & Rogers, D. C. & Ross, A. & Schotte, M. & Schram, F. R. & Shih, C. - T. & Watling, L. & Wilson, G. D. F. & Turgeon, D. D. 2005: 257
Edmondson, C. H. 1962: 4
1962
Loc

Platyozius laevis

Rathbun, M. J. 1906: 861
1906
Loc

Pseudozius (Platyozius) laevis

Garth, J. S. 1971: 185
Borradaile, L. A. 1902: 243
1902