OXYSTOMATOUS AND ALLIED CRABS OF AMERICA 259 



Family HAPALOCARCINIDAE Caiman 



Hapalocarcinidae Calman, Trans. Linn. Soc. London, Zool., ser. 2, vol. 8, 

 p. 3, 1900 ("Incertae sedis"). — Borradaile, in Gardiner's The fauna and 

 geography of the Maldive and Laccadive Archipelagoes, vol. 1, p. 271, 

 1902; Ann. Mag. Nat. Hist., ser. 7, vol. 19, p. 483, 1907.— Verrill, Trans. 

 Connecticut Acad. Arts and Sci., vol. 13, p. 427, 1908. — Potts, Pap. Marine 

 Biol. Carnegie Inst. Washington, vol. 8, p. 67, 1915. — Rathbun, U. S. Nat. 

 Mus. Bull. 97, p. 15, 1918. — Shen, Hong Kong Nat., suppl. 5, p. 21, 

 1936. 



Meriis of third maxillipeds small, bearing terminally a carpus of 

 nearly its own width; ischium very broad. Body somewhat oblong. 

 Antennules not retractile into sockets. Parasitic or symbiotic in corals. 



KEY to the AMERICAN GENERA OF THE FAMILY HAPALOCARCINIDAE 



A'. Carapace smooth, anterolateral margin entire Hapalocarcinus (p. 259) 



A^. Carapace more or less granulate or spined, anterolateral margin 



denticulate Cryptochirus (p. 262) 



Genus HAPALOCARCINUS Stimpson 



Hapalocarcinus Stimpson, Proc. Boston Soc. Nat. Hist., vol. 6, p. 412, 1859 

 (type, H. marsupialis Stimpson). 



Front of carapace not bent downward; anterolateral margin and 

 front not denticulate. Antennules not retractile into fossettes; 

 antennae very small and orbits ill defined. Basal article of antennules 

 with a stout dentiform lobe anteriorly. Abdomen of female much 

 enlarged. Live in galls, which are formed to accommodate the crabs 

 by the corals on which they make their homes. 



Islands of the Pacific and Indian Oceans; west coast of Central and 

 South America. 



HAPALOCARCINUS MARSUPIALIS Stimpson 



Figure 46; Plate 79, Figures 3-9 



Hapalocarcinus marsupialis Stimpson, Proc. Boston Soc. Nat. Hist., vol. 6, 

 p. 412, 1859 (type locality, Hilo, Hawaii; type not extant); Smithsonian 

 Misc. Coll., vol. 49, p. 170, pi. 14, fig. 8, 1907.— Calman, Trans. Linn. Soc. 

 London, ser. 2, vol. 8, p. 43, pi. 3, fig. 29-40, and synonymy, 1900. — Bor- 

 radaile, in Gardiner's The fauna and geography of the Maldive and Lac- 

 cadive Archipelagoes, vol. 1, p. 271, 1902. — Rathbun, Bull. U. S. Fish 

 Comm. for 1903, pt. 3, p. 892, 1906; Trans. Linn. Soc. London, ser. 2, vol. 14, 

 p. 242, 1911. — Potts, Pap. Mar. Biol. Carnegie Inst. Washington, vol. 8, 

 p. 35, figs. 5C, 6B, 7B and D, 8B, 9-15, pis. 1, 2, 1915.— Edmondson, 

 Bernice P. Bishop Mus. Bull. 5, p. 24, 1923. — Shen, Hong Kong Nat., 

 suppl. 5, p. 22, 1936. — Schmitt, Explorations and field-work of the Smith- 

 sonian Institution in 1935, pp. 34-36, figs. 36a-f, 1936. 



Description. — Female. Carapace soft and membranous, depressed, 

 broadly oval in outline and truncated in front and behind. Breadth 

 equal to, or a little less than length. Front slightly deflexed, biden- 

 tate (or obscurely tridentate). Lateral margins rounded off dorso- 



