PEREZ FARFANTE: AMERICAN SOLENOCERID SHRIMPS 



FIGURE 19. — Hymenopenaeus doris, syntype 9 32.5 mm cl, off Cabo Velas, Costa Rica. A, Thelycum, ventral view. 

 B, syntype 2 32 mm cl, same locality, thelycum, ventrolateral view (setae omitted). 



median lamella of sternite XIII; lamella, project- 

 ing vertically, heavily sclerotized, excavate ante- 

 riorly, with distal margin truncate or convex; pair 

 of high ridges (triangular in cross section) 

 flanking and posteriorly overlapping median 

 lamella; posterior part of sternite XII bearing 

 paired short, blunt horns covered by long setae. 



Maximum size. -Females: 33.5 mm cl. 



Geographic and bathymetric ranges. -Eastern 

 Pacific: from off Punta Chivato (27°09'N, 

 111°42'W), Gulf of California, to Isla del Coco, 

 Costa Rica (Figure 20), at depths between 549 and 

 4,082 m (Figure 9). Burkenroad (1938) cited the 

 depth, 300 fm (549 m), at which one juvenile speci- 

 men was taken from the Arcturus off Isla del Coco, 

 but did not give the coordinates of the locality. 

 Beebe ( 1926), however, indicated that the various 

 hauls from the Arcturus in the area were made 

 slightly south of Isla del Coco, and cited the 

 following coordinates: 4°30'N, 87°00'W. 



Affinities -Hymenopenaeus doris is closely allied 

 to H. nereus, the only other member of the genus 

 known from the American Pacific. Females of the 



two species -can be distinguished readily by thely- 

 cal features: in//, doris a strong median protuber- 

 ance is present on sternite XIV, and the lamella 

 on the posterior margin of sternite XIII is disposed 

 vertically, is deeply excavate anteriorly, and its 

 distal margin is truncate or convex; in H. nereus 

 only a median longitudinal rib is present on ster- 

 nite XIV, and the lamella on XIII is inclined 

 anteriorly, is flattened, and its distal margin is 

 concave. Finally, in//, doris the lamella is flanked 

 by high ridges whereas in H. nereus these are 

 replaced by flattened, scalelike processes directed 

 caudally. 



Remarks-Only nine specimens of H. doris are 

 known. Seven, five of which are syntypes, were 

 collected by the Albatross (1891); one of these (not 

 designated by Faxon as part of the type-series) 

 was taken with four syntypes at Albatross stn 

 3414, and the seventh was caught in the Gulf of 

 California at Albatross stn 3009. Two additional 

 specimens were cited by Burkenroad (1938), a 

 juvenile female from the mouth of the Gulf of 

 California, and another juvenile from off Isla del 

 Coco (Costa Rica) taken by the Arcturus in 300 fm 

 (549 m). 



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