PART 1 GARTH : PACIFIC OXYRHYNCHA 241 



Genus EUPLEURODON Stimpson 



Eupleurodon Stimpson, 1871a, p. 98. Miers, 1879c, p. 650. Rathbun, 



1925, p. 160. 

 Euplorodon A. Milne Edwards, 1878, p. 141. 



Type: Eupleurodon trifurcatus Stimpson, by monotypy. 



Description: Allied to Epialtus, but with a depressed and uneven 

 carapace. Anterolateral angles of the carapace strongly prominent, form- 

 ing projecting teeth directed forward, almost parallel to the axis of the 

 body. Ambulatory [legs] strongly prehensile, with dentigerous penult 

 [articles]. Size small. (Stimpson) Five free abdominal articles in both 

 sexes. 



Range: Cape San Lucas, Lower California, Mexico, and from 

 Manta, Ecuador, to Chincha Islands, Peru ; Galapagos Islands. Not 

 found in the Atlantic. Intertidal. 



Key to the Genus Eupleurodon 

 ( Based Upon Female Characters in the Absence of Males of 



Two Species) 



la. Hepatic width exceeding branchial, tip of rostrum slightly 



emarginate, orbital margin arched but not toothed, merus of 



external maxilliped notched to receive palpus 



2a. Orbital margins continuous with anterolateral and concave, 



hepatic lobes large, directed outward as well as forward. 



trifurcatus 



2b. Orbital margins convex, anterolateral margins straight, 

 hepatic lobes small, directed forward. Galapagos only. 



rathbunae 



lb. Branchial width equaling or exceeding hepatic, tip of rostrum 



bilobed, a strong preorbital tooth (lacking in male), merus 



of external maxilliped entire or nearly so. . peruvianus 



Eupleurodon trifurcatus Stimpson 

 Plate N, Figs. 1-6 



Eupleurodon trifurcatus Stimpson, 1871a, p. 98. A. Milne Edwards, 

 1878, p. 142. Rathbun, 1910, pp. 535, 572 (part: not the Ferrol 

 Bay, Peru, specimen; not pi. 49, fig. 5) ; 1925, p. 160. 

 Type: Female holotype, not extant. 



Type locality: Cape San Lucas, Lower California, Mexico; John 

 Xantus, collector. 



