PART 1 garth: pacific oxyrhyncha 179 



of chela 7.5 mm, of dactyl 3.6 mm, height of palm 2.3 mm, length of 

 ambulatory legs 24.5, 18.5, 16.3, and 13.7 mm, respectively. Male 

 paratype: length 24.0 mm, width 14.8 mm. 



Diagnosis: Carapace broad, width greater than length posterior to 

 gastric tubercle. Preorbital horns divergent, equaling or exceeding rostral 

 horns. External maxilliped inflated, basal projection of exognath not 

 recurving over ischium; ischium without a groove. First free antennal 

 segment flattened. Male first pleopod with a terminal triangular opening, 

 protecting flap rudimentary, not extending to tip. Galapagos only. 



Description: Carapace broad, particularly at hepatic level, gastric and 

 cardiac regions elevated and tuberculate, branchial regions depressed, a 

 strong ridge extending from gastric onto anterior branchial region 

 separating the posterior portion of the roughly hexagonal carapace from 

 the laterally depressed and medially declivitous anterior portion. Frontal 

 region composed of four conspicuous flattened horns, two rostral, two 

 preorbital. Rostral horns small, subparallel, separated to bases, tips 

 broadly rounded, a spinous projection extending inward and upward 

 from the midpoint of each and all but meeting in the midline. Preorbital 

 spines strongly divergent, their blunt tips overreaching the rostral horns 

 although inclined in a plane above them. The posterior projection of the 

 orbit and the hepatic lobe, although separated by a deep notch, together 

 forming a leaflike process concealing the long eyestalk and all but the 

 tip of the cornea from dorsal view. Lateral branchial margins rounded 

 and bearing two or three setose tubercles. Four clusters of stout, hooked 

 hairs forming a square outlining the gastric region, and a double row 

 lining the outer margin of each rostral horn. Longer and softer hairs 

 fringing the inner margin of the preorbital spines and the margins of 

 the carapace posterior to the orbito-hepatic suture. Posterior margin 

 lamellate and faintly trilobed. 



Basal antennal article broadened, a low ridge on inner margin, outer 

 margin delimiting the open orbit. First free segment flattened, second 

 cylindrical and half the length of the first, both segments fringed with 

 coarse hair. 



External maxillipeds unusually broad, endognath with ischium and 

 merus inflated, strongly convex, and appearing as if coalesced ; exognath 

 with basal projection directed posteriorly, rather than recurving onto 

 ischium ; ischium without a longitudinal groove. Inner margin of ischium 

 entire, merus inserting deeply into outer margin but not recurving, as in 

 Tyche lamellifrons and T. emarginata. (It is the configuration of the 



