Villoplax peruvianus ( Garth, 1973 ), 2010

CASTRO, PETER & NG, PETER K. L., 2010, Revision of the family Euryplacidae Stimpson, 1871 (Crustacea: Decapoda: Brachyura: Goneplacoidea), Zootaxa 2375 (1), pp. 1-130 : 113-115

publication ID

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

persistent identifier

https://treatment.plazi.org/id/03F487A8-392C-4256-7D8C-FA99F645FA64

treatment provided by

Felipe

scientific name

Villoplax peruvianus ( Garth, 1973 )
status

comb. nov.

Villoplax peruvianus ( Garth, 1973) View in CoL , new combination

( Figs. 47A–D View FIGURE 47 ; 48A–G View FIGURE 48 )

Goneplax sp. — Chirichigno 1970: 61, fig. 150.

Trizocarcinus peruvianus Garth, 1973: 9 View in CoL , fig. 5 [ Perú]. — Wicksten 1989: 303 [in list], 316 [in list]. — Ng et al. 2008: 78 [in list].

Type material. Pre-adult female holotype, 13.4 mm × 19.1 mm ( AHF 699 View Materials , now LACM) ( Fig. 47A, B View FIGURE 47 ); 1 male paratype, 19.9 mm × 28.7 mm ( AHF 705 View Materials ; now LACM) ( Fig. 47C, D View FIGURE 47 ) .

Type locality. Perú, off Paita , 144 m.

Material examined. Perú. Off Paita , stn. 106, 144 m, E. N. del Solar coll.: 1 male paratype, 19.9 mm × 28.7 mm ( AHF 705 View Materials , now LACM), pre-adult female holotype, 13.4 mm × 19.1 mm ( AHF 699 View Materials , now LACM) .

Diagnosis. Carapace with one short, acute tooth on each anterolateral border ( Figs. 47A, B View FIGURE 47 ; 48A View FIGURE 48 ). Ambulatory legs with long, conspicuous tomentum ( Fig. 48A View FIGURE 48 ).

Remarks. The holotype, regarded as a female by Garth (1973) is actually a pre-adult specimen where the vulvae are barely visible and closed.

Distribution. Only known from northern Perú, Tropical Eastern Pacific region. Depth: subtidal to at least 144 m.

Genus Xenocrate Ng & Castro, 2007

Xenocrate Ng & Castro, 2007: 45 View in CoL View Cited Treatment . — Ng et al. 2008: 78 [in list]. — De Grave et al. 2009: 33 [in list].

Diagnosis. Carapace ( Fig. 49A View FIGURE 49 ) subhexagonal, almost as wide as long, dorsal surface granular without clear indication of regions; anterolateral borders arched; front wide, nearly straight with median notch, transverse sulcus along margin. Two short teeth (second acute, dorsally salient; small third tooth in small individuals) posterior to short, rounded outer orbital angle. Orbits ( Fig. 49C View FIGURE 49 ) short, shorter than front, wide, spherical; 2 notches, large, thick inner suborbital tooth, shorter, thick median tooth, outer notch on thick suborbital border ( Fig. 49B, C View FIGURE 49 ); eye peduncles short, about as long as cornea ( Fig. 49C View FIGURE 49 ); large, spherical corneas. Basal antennal article immobile, orbital hiatus is closed excluding antennal flagellum from orbit ( Fig. 49B, C View FIGURE 49 ). Anteroexternal margin of third maxilliped merus auriculiform ( Fig. 49B View FIGURE 49 ). Cheliped fingers ( Fig. 49D View FIGURE 49 ) moderately stout, slightly longer than swollen propodus, dark in colour; carpus with tooth on inner margin; glabrous. Dorsal margins of ambulatory legs (P2–P5) meri, carpi, propodi unarmed, dactyli slender, smooth, setose; P5 propodus, dactylus proportionally short, flattened, fringed with many short setae ( Fig. 49A View FIGURE 49 ). Thoracic sternum ( Fig. 49G, H View FIGURE 49 ) wide; thoracic suture 2/3 complete, straight ( Fig. 49G View FIGURE 49 ); 3/4 deep, short, interrupted; 3/4 deep, short, interrupted; 4/5, 6/7, 7/8 interrupted, 5/6 complete ( Fig. 49G, H View FIGURE 49 ); median groove on thoracic sternites 7, 8. Sterno-abdominal cavity of male deep, nearly reaching anterior margin of sternite 4 ( Fig. 49G View FIGURE 49 ). Press-button of male abdominal-locking mechanism as large tubercle near thoracic suture 4/5 ( Fig. 49G View FIGURE 49 ) (presence in preadult 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. 49E View FIGURE 49 ); somite 3 transversely reaching inner margins of P5 coxae; no portions of thoracic 8 exposed by closed abdomen, somite 2 transversely shorter than somite 3 ( Fig. 49F View FIGURE 49 ). G1 long, slender, slightly sinuous, acuminate apex, with small denticles ( Fig. 50A–C View FIGURE 50 ); G2 less than one-third of G1, apex flattened, with obtuse tip ( Fig. 50D View FIGURE 50 ). Male genital opening (gonopore) coxal; coxo-sternal disposition of long penis, protected by concave posterior portion of thoracic sternite 7 ( Ng & Castro 2007: fig. 3B). Female abdomen relatively narrow, not covering outer portions of thoracic sternum ( Ng & Castro 2007: fig. 5B). Vulva ovoid, with thick borders, extending across anterior portion of sternite 6 close to median axis of thorax ( Fig. 49H View FIGURE 49 ); covered by soft membrane, sternal vulvar cover absent. Remarks. This monotypic genus was recently described from specimens collected in the Philippines ( Ng & Castro 2007: 45, figs. 1–5). It is herein reported for the first time from the Solomon Is. and Vanuatu, which suggests a more extensive geographical distribution.

The G2 has a unique flattened apex with an obtuse tip instead of the two unequal processes characteristic of most euryplacids, with the basal, much shorter process missing ( Fig. 50D View FIGURE 50 ). Other characters of Xenocrate are summarized in Table 1.

Species included. Xenocrate peculiaris Ng & Castro, 2007 The genus is restricted to the Indo-West Pacific region.

LACM

Natural History Museum of Los Angeles County

Kingdom

Animalia

Phylum

Arthropoda

Class

Malacostraca

Order

Decapoda

Family

Euryplacidae

Genus

Villoplax

Loc

Villoplax peruvianus ( Garth, 1973 )

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

Xenocrate

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
Ng, P. K. L. & Castro, P. 2007: 45
2007
Loc

Trizocarcinus peruvianus

Ng, P. K. L. & Guinot, D. & Davie, P. 2008: 78
Wicksten, M. K. 1989: 303
Garth, J. S. 1973: 9
1973
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