FISHERY BULLETIN: VOL. 75, NO. 2 



length of ventral margin of pleuron and from 

 there anteriorly to ventral angle of latter. 



Maximum size-Males: 15 mm cl, about 66 mm tl; 

 females: 23 mm cl, about 82 mm tl. 



Geographic and bathymetric ranges. -In the 

 western Atlantic: from off Cape Lookout, N.C. 

 (34°15'N, 75°58'W), southward to the Straits of 

 Florida, in the northeastern part of the Gulf of 

 Mexico (northwest of Charlotte Harbor, Fla.), and 

 throughout the Caribbean. In the eastern Atlan- 

 tic: off Cape Verde Islands (Figure 49). This spe- 

 cies has been found at depths between 165 and 

 570 m (Figure 9), with one dubious record from 

 Haiti at 77 m. 



Affinities. -Hadropenaeus affinis, which is amphi- 

 Atlantic, and H. modestus, found only in the 

 western Atlantic, are closely allied, but can be 

 distinguished by the characters presented in 

 Table 1. 



Burkenroad (1936), for unexplained reasons, 



expressed doubt that H . affinis is different from 

 H. modestus, an opinion apparently shared by 

 Bullis and Thompson (1965) who recognized only 

 H. modestus in their western Atlantic collections. 

 I have examined part of their material and found 

 that it also includes H. affinis. On the basis of 

 the original description of H. modestus (Smith 

 1885), Bouvier (1906b) distinguished H. affinis 

 from the former species by six features. I have 

 found that two of them are diagnostic: the relative 

 length of the scaphocerite, and the ratio length 

 of dactyl/length of propodus of the fourth pereopod 

 (see Table 1). The number of rostral teeth is not 

 7 in H. modestus as Smith indicated, but 6 in all 

 specimens I have examined, the number usually 

 possessed by H. affinis. The relative length of 

 the antennular flagella, which Bouvier indicated 

 was greater in H. affinis, varies within a given 

 length of carapace, and may be the same in ani- 

 mals of the two species, e.g., 1.9 times carapace 

 length in shrimp 23 mm cl. The carpus of the 

 fourth pereopod is longer than the merus in both 

 species, and not shorter in H. modestus, as Bou- 



TT^ 



o H. affinis 

 . H. modestus 



FIGURE 49. — Ranges of Hadropenaeus affinis and Hadropenaeus modestus based on published records and specimens personally 



examined. 



322 



