298 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 21 



Notolopas mexicanus Garth 

 Plate Q, Fig. 9; Plate 33, Fig. 2 



Notolopas mexicanus Garth, 1940, p. 61, pi. 14, figs. 1-4. 



Type: Male holotype, U.S.N.M. No. 91081, length 7.5 mm, width 

 5.2 mm. 



Type locality: South and west of White Friars, Guerrero, Mexico, 

 25 fathoms, Velero III station 264-34. 



Localities subsequently recorded: Known only from the type locality. 



Atlantic analogue: Notolopas brasiliensis Miers. 



Diagnosis: Posterior margin of carapace smoothly rounded, no carina 

 or posterior marginal spine. Cardiac region high, domed. Rostrum short, 

 horns little diverging. Basal antennal article with a shallow lobe on outer 

 margin. Merus of external maxilliped subtriangular. Tip of male first 

 pleopod triangular, acuminate, setiferous, and sharply bent at an angle 

 of 90° ; tip opposed by a smaller, thinly rimmed lobe in which aperture 

 is situated. 



Description: Carapace subpyriform, convex, and posteriorly rounded. 

 Regions elevated, separated by deep, naked sulci and surmounted by well- 

 defined tracts of curved setae with the two epigastric most isolated. 

 Rostrum short, horns divergent and papillate, each bearing two rows of 

 curved setae, tips incurving. Supraocular spine slender and curving for- 

 ward ; postocular cup broad, exteriorly flattened, a minute tooth between 

 pre- and postocular projections. Four equidistant setose tubercles, one 

 gastric, two branchial, and one intestinal, forming a diamond on cara- 

 pace ; cardiac area dome-shaped, well separated from branchial swellings. 

 Intestinal area projecting slightly below the general level of the posterior 

 border; no lamellate posterior carina. Basal antennal article wide, con- 

 cave, edge thin, a blunt spine at anteroexternal angle, a shallow lobe 

 near base, and a tubercle opposite green-gland opening; first movable 

 segment slender, spinulous, reaching nearly to tip of rostrum and visible 

 in dorsal view ; flagellum overreaching rostrum by twice its length. Merus 

 of third maxilliped produced at both internal and external distal angles 

 until almost triangular; ischium with internal margin spinulous. Two 

 compressed lobes on pterygostomian ridge. A pair of deep sternal inden- 

 tations opposite coxae of chelipeds. 



Chelipeds of male stouter than legs, merus and propodus of approxi- 

 mately equal length. Merus with four evenly spaced tubercles along 

 inferior margin, the proximal being largest. Manus moderately com- 

 pressed, fingers gaping slightly at base, regularly toothed, tips crossing. 



