Glyptoxanthus corrosus ( A. Milne-Edwards, 1869 )

Mendoza, Jose Christopher E. & Guinot, Danièle, 2011, Revision of the genus Glyptoxanthus A. Milne-Edwards, 1879, and establishment of Glyptoxanthinae nov. subfam. (Crustacea: Decapoda: Brachyura: Xanthidae), Zootaxa 3015, pp. 29-51 : 37

Glyptoxanthus corrosus ( A. Milne-Edwards, 1869)

( Figs. 4 , 10 D)

Xantho corrosus A. Milne-Edwards, 1869: 376 (type locality: St. Vincent Is., Cape Verde). Actaea (Glyptoxanthus) corrosa, Monod 1956: 298 .

Glyptoxanthus corrosus, Bouvier 1922: 67 , pl. 6 figs. 4, 6. — Guinot 1967: 556, fig. 21; 1971: 1073; 1979: 68, figs. 9, 18E. — Manning & Holthuis 1981: 135. —Ng et al. 2008: 199 (list).

Material examined. Cape Verde: Holotype, male (dry), 26.6 × 18.7 mm (MNHN-B3015), St. Vincent Is., coll. M. Bouvier, 1868-1869.

Diagnosis. Carapace transversely ovate, width-to-length ratio 1.4; gastric, branchial, cardiac and intestinal regions well separated by wide and deep furrows, but subregions (i.e., 1M+2M+3M; 1L+2L+3L+4L+5L+6L) more-or-less fused; 4M distinct, bridging gastric and cardiac regions; carapace vermiculations showing traces of fused granules, anastomosing, forming a regular reticulate pattern, particularly on gastric and branchial regions. Anterolateral margin poorly divided into low lobes, last lobe most definite. Anterior thoracic sternum moderately eroded, with somewhat reticulate sculpturing. G1 long and slender, apex somewhat tapering and devoid of setae, studded with spiniform granules.

Remarks. Alphonse Milne-Edwards (1869) described Xantho corrosus from St. Vincent Island, in the Cape Verde Archipelago, and later ( A. Milne-Edwards 1879) he transferred it to his new genus Glyptoxanthus . It is easily distinguished from a sympatric species, G. cavernosus ( A. Milne-Edwards, 1878) , and from other congeners by the unique sculpturing of the dorsal carapace: i.e. fused carapace subregions, anastomosing and reticulate pattern of vermiculations, and wide and deep cervical and branchio-cardiac grooves.

Ecology and geographical distribution. Glyptoxanthus corrosus is a singular and rare species, only known from the type specimen, which is from Cape Verde, off the northwestern coast of Africa. Very little is known about the biology of this species (see Guinot 1979).

Figures

FIGURE 4. Glyptoxanthus corrosus (H. Milne Edwards, 1834), holotype, male, 26.6 × 18.7 mm (MNHN-B 3015), Cape Verde: A, dorsal view; B, anterior view; C, ventral view; D, right chela, external view.

FIGURE 10. Glyptoxanthus spp. gonopods (G 1). A, G. angolensis (Brito Capello, 1866); B, G. cavernosus (A. Milne-Edwards, 1878); C, G. erosus (Stimpson, 1859); E, G. c o r ro s u s (H. Mile Edwards, 1834); E, G. labyrinthicus (Stimpson, 1860), (LACM CR 1935.075.3); F, G. meandricus (Lockington, 1877), neotype (LACM CR 1940.65); G, G. vermiculatus (Lamarck, 1818). (A – C, D, G, after Guinot 1979).