PART 1 GARTH : PACIFIC OXYRHYNCHA 373 



extant, according to Dr. I. Gordon of the British Museum (Natural 

 History). In view of this fact, and in accordance with the Copenhagen 

 Decisions on Zoological Nomenclature, a male specimen from Manta, 

 Ecuador, A.H.F. No. 353, collected by the Velero III on January 19, 

 1935, at station 400-35, is hereby designated neotype. 



Type locality: As stated in the second paragraph under Remarks 

 below, the Galapagos Islands type locality, correct for Mithrax (Mith- 

 raculus) nodosus Bell, is in error with respect to M. (Mithraculus) 

 denticulatus, subsequent collecting having shown the ranges of the two 

 species to be mutually exclusive. The corrected type locality for M. 

 (Mithraculus) denticulatus Bell is Manta Bay, Ecuador, one of Cum- 

 ing's mainland localities from which Hancock expeditions obtained mate- 

 rial. 



Localities subsequently reported, with collectors: Extralimital: Cali- 

 fornia: San Diego (locality supposed correct), San Diego Society of 

 Natural History (Rathbun, 1925, as Mithrax (Mithraculus) areolatus). 

 Mexico: Lower California: L. Diguet (Bouvier) ; Cape San Lucas, 

 John Xantus (Stimpson) ; Gulf of California: [Los] Coronados Islands, 

 Pt. Lobos of Espiritu Santo Island, El Mogote, east of La Paz, and 

 Pulmo Reef, Steinbeck and Ricketts (Steinbeck and Ricketts, as Mithrax 

 areolatus) ; Port [Puerto] Escondido and San Jose Island, W. J. Fisher, 

 types of Mithrax areolatus (Lockington) ; Arena Bank, Zaca (Crane, 

 1937, as Mithrax (Mithraculus) areolatus). Mexico south of Cape 

 Corrientes: Chamela Bay, Sihuatenejo, Port Gatulco, and Tangola 

 Tangola Bay, Zaca (Crane, 1947) ; Manzanillo, F. Bonet, and Aca- 

 pulco, Escuela Nacional (Buitendijk, 1950). Costa Rica: Port Parker, 

 Port Culebra, Piedra Blanca Bay, and Uvita Bay, Zaca (Crane, 1947) ; 

 Cocos Island, Arcturus (Boone). Panama: Capt. John Dow (Rathbun, 

 1892) ; Bahia Honda, Zaca (Crane, 1947) ; Flamenco Island, E. Festa 

 (Nobili) ; Perico Island, Albatross (Rathbun, 1907); Perlas Islands, 

 Vettor Pisani (Cano). Ecuador: Santa Elena Bay, E. Festa (Nobili) ; 

 extralimital: Guayaquil, A. Sinclair (White). 



Atlantic analogue: M. (Mithraculus) coryphe (Herbst). 



Diagnosis: Oblique branchial sulci strong. Two lobes and a forward 

 curving spine on anterolateral margin ; a postlateral spine followed by a 

 dorsal row of tubercles. Inner edge of carpus only of cheliped laminate, 

 lamina faintly bilobed. Carapace wide, breadth exceeding length by 

 nearly one-half. Male first pleopod with broadly pointed tip and two 

 rounded flanges. 



