416 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 5 



Superfamlly BRAGHYRHYNGHA 

 Y^mWyPORTUNIDAE 



Subfamily ThALAMITINAE 



Genus PORTUNUS Weber, 1795 



Key to the Galapagos Species of the Genus Portunus 



A^ A spine at posterior angles of the carapace ; merus of swimming 



leg unarmed P. (Achelous) tuberculatus 



A^ No spine at posterior angles of the carapace ; a spine at postero- 

 distal angle of merus of swimming leg 

 B^ Carapace with numerous areolations ; lateral spine as long as 



width of 3 adjacent teeth . . P. (Achelous) stanfordi 

 B^ Carapace flat and smooth ; lateral spine no longer than larg- 

 est of anterolateral spines . . P. (Achelous) angustus 



Subgenus AcHELOUS de Haan 



Portunus (Achelous) stanfordi Rathbun 



Plate 71, Fig. 1 



Portunus (Achelous) brevimanus Rathbun, Proc. U.S. Nat. Mus,, vol. 

 21, p. 593, 1898; vol. 38, p. 578, 1910 (part: the Galapagos speci- 

 mens). 

 Portunus (Achelous) stanfordi Rathbun, Proc. Washington Acad. Sci., 

 vol. 4, p. 282, pi. 12, fig. 11, 1902; Bull. 152, U.S. Nat. Mus., p. 

 69, pi. 31, text fig. 11, 1930. Boone, Zoologica, vol. 8, no. 4, p. 178, 

 fig. 60, 1927. 

 Type locality. — Tagus Cove, Albemarle Island. 

 Type.—\J?>NM No. 24833. 



Range. — Tagus Cove, Albemarle Island (Hopkins-Stanford Expedi- 

 tion), and Hood Island (Arcturus) ; known only from the Galapagos 

 Islands. 



Diagnosis. — Carapace with numerous lumpy elevations. Lateral spine 

 almost transverse, its length equal to the width of the two adjacent teeth. 

 A spine at the posterodistal angle of the merus of the fourth leg. 

 Material examined (234 specimens from 40 stations). — 

 9-32. Tagus Cove, Albemarle Island, Jan. 6, 1932, surface at light, 

 1 female. 

 55-33. Lat. 1° 03' 30'' S, Long. 90° 17' 30" W, 60 fms, Feb. 5, 1933, 



1 young male. 

 78-33. Conway Bay, Indefatigable Island, surface at light, Feb. 15, 

 1933, 2 males, 2 females. 



