PART 1 GARTH : PACIFIC OXYRHYNCHA 425 



Genus THOE Bell 



Thoe Bell, 1835b, p. 170. A. Milne Edwards, 1878, p. 120. Rathbun, 



1925, p. 347. 

 Platypes Lockington, 1877b, p. 41 ; type: P. edentata Lockington, 1877 = 

 Thoe sulcata Sti'mpson, by monotypy. 



Type: Thoe erosa Bell, by monotypy. 



Description: Carapace little elongate, depressed, its surface lobulate : 

 interorbital region broad ; rostrum scarcely advanced, no preorbital 

 spines ; supraorbital border without spines. Basal article of the external 

 antennae short and extremely broad ; second article somewhat flattened, 

 nearly reaching the extremity of the rostrum, and inserted at the sides 

 of the latter at a great distance from the orbit. External article of the 

 outer maxillipeds, or exognath, much broadened in its middle portion. 

 Sternal plastron nearly circular. 



Chelipeds of the male long and strong. Manus laterally compressed ; 

 the fingers, excavated into a spoon shape, leaving between them, when 

 close together, a more or less considerable space varying according to 

 sex and age. In young individuals and in females the fingers in contact 

 for most of their length. 



Ambulatory legs heavy; merus decorated with longitudinal crests; 

 propodus and dactylus remarkably small and bearing some nodosities. 

 Second pair of legs [first ambulatories] notably longer than the others; 

 the fifth pair [fourth ambulatories] very small. (A. Milne Edwards, 

 modified) 



Abdomen seven-segmented in both sexes. (Bell) 



Range: Eastern Pacific from Tepoca Bay, Sonora, Mexico, to Santa 

 Elena Bay, Ecuador; Revilla Gigedo and Galapagos Islands. Western 

 Atlantic from Key West, Florida, to Curagao, Netherlands West Indies. 

 Shore to 2.5 fathoms. 



Key to the Pacific Species of Thoe 



la. Only one anterior tooth or lobe on the basal antennal article. 

 Tooth in gape of mature male cheliped bicuspid. A double row 



of deep excavations on the arm erosa 



lb. Two anterior teeth or lobes on the basal antennal article 



2a. Tooth in gape of mature male cheliped simple. A superior 

 row of spinules on meri of walking legs. Outer row of 

 excavations on arm deep as inner row . sulcata sulcata 



