Figube 136. — Calappa sulcata Rathbun. A, male first 

 pleopod in ventral view, approximately X 3 ; B, male 

 second pleopod in dorsal (anterior) view, approximately 

 X 3 ; C, abdomen of male, approximately X 0.8 ; D, 

 abdomen of female, approximately X 0.6 ; A-C from 

 near Margarita Island, Venezuela ; D from Surinam 

 (after Holthuis, 1958). 



Chelipeds with outer surface of palm divided 

 into three zones as in preceding species; large 

 tubercles of lower zone low and inconspicuous; 

 zones one, two, and three each separated by a row 

 of sharply pointed tubercles; middle zone not 

 extending horizontally, but curving dorsally in 

 distal part, smooth, with minute granules; zone 

 three smooth, except for two low, inconspicuous, 

 granular tubercles near upper margin of palm; 

 granulations on palm more distinct in females 

 than in males; tooth on outer, lower, proximal 

 surface of palm nearly rectangular in large in- 

 dividuals, slender and acute in smaller ones. Meral 

 articles of walking legs with granules on lower 

 surface. 



Measurements. — Carapace: male, length, 77 

 mm., width, 98 mm.; female, length, 92 mm., 

 width, 119 mm. 



Color. — In alcohol, often light pinkish brown 

 with small, narrow rings of dark red, median ring 

 most conspicuous; each carpus with a ring, and 

 each palm with one near upper margin enclosing 

 tubercle toward proximal end of margin (Rath- 

 bun, 1937). 



Habitat. — Twelve to 100 fathoms (Cerame- 

 Vivas, personal communication). 



Type locality.— Oft Louisiana, lat. 29°24'30" N., 

 long. 88°0r W., depth, 35 fathoms. 



Known range. — Cape Hatteras, N.C., to Gulf of 

 Mexico; through West Indies to French Guiana. 



Remarks. — Hildebrand (1954) reported this 

 species (under the name C. spring en) as con- 

 spicuous but never abundant in the western and 

 northwestern Gulf of Mexico at depths of 12 to 

 35 fathoms. One ovigerous female was found in 

 May off Padre Island, Tex. 



Genus Acanthocarpus Stimpson, 1871 



Rathbun, 1937, p. 220. 



Acanthocarpus alexandri Stimpson 



Figure 137 



Acanthocarpus alexandri Stimpson, 1871a, p. 153. — Rathbun, 

 1937, p. 221, pi. 69, figs. 1-2 (rev.). 



Recognition characters. — Carapace ovate, regu- 

 larly convex, widest in anterior half; surface un- 

 even, granulate, and punctate, with protuberances 

 arranged longitudinally in roughly five rows cen- 

 trally, and two shorter, intercalated rows behind 

 orbits; all rows formed into ridges, those adjacent 

 to midline each terminating in a spine on postero- 

 lateral margin. Posterior margin arcuate bearing 

 a low eminence at middle; inferior margin of 

 pterygostomian region with a row of 7 to 11 

 strong, widely spaced, oblique ridges of varying 

 length. Orbits large, margins ciliated. 



Chelipeds strong; merus bispinose on distal 

 outer surface, inferior spine strong and a little 

 longer or shoiter than half width of carapace, 

 superior spine one-fourth to one-third length of 

 inferior spine; hand with superior crest of 7 

 closely placed teeth, and an oblique 6-toothed crest 

 on outer surface extending from base of dactyl to 

 posteroinferior angle, scattered tubercles between 

 crests; inner surface of hand with stridulating 

 ridge composed of about 45 oblique, closely placed 

 striae which can be played against oblique ridges 

 of peterygostomian region. Walking legs smooth. 

 Sternal plastron with a conical tubercle on either 

 side of first article. 



Measurements. — Male carapace: length, 13 

 mm. ; width, 32 mm. 



Color. — Dorsal surface of carapace and cheli- 

 peds pale reddish orange, deepest in hue on eleva- 

 tions of carapace and bases of meral spines of 

 chelipeds; underparts white, slightly tinged with 

 red (Rathbun, 1937). 



Habitat.— Thirty-seven to 208 fathoms. 



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