PEREZ FARFANTE AMERICAN SOLENOCERID SHRIMPS 



than 0.5 length of dactyl. Third pereopod rather 

 slender, exceeding antennular peduncle by tip or 

 by entire length of dactyl. Fourth pereopod very 

 slender, shorter than third, surpassing carpo- 

 cerite by tip or by entire length of dactyl; length 

 of dactyl 0.65-0.75 that of propodus; length of 

 carpus about 1.1 times that of merus. Fifth pereo- 

 pod very slender and long, overreaching anten- 

 nular peduncle at least by length of dactyl and 

 propodus, and at most by their length and 0.2 

 length of carpus. Order of pereopods in terms of 

 their maximal anterior extensions; first, second, 

 fourth, third, and fifth. First pereopod with very 

 long, slender spine on basis, small spine on disto- 

 mesial margin of ischium, and rather minute one 

 near midlength of mesial margin of merus. Second 

 pereopod with long spine on basis. Coxa of fourth 

 and fifth pereopods in males armed with anterior 

 spine. Coxa of fifth pereopod in females mesially 

 produced into short plate, lacking spine on antero- 

 mesial margin; minute spine present in young. 



Abdomen with high, sharp, median keel from 

 fourth through sixth somites, low, rounded carina 

 sometimes present on third; posterodorsal margin 



of third, fourth, and fifth somites with median 

 incision; sixth somite bearing sharp spine at 

 posterior end of keel, and minute spine on postero- 

 ventral angles. Telson (Figure 46B) with median 

 sulcus deep anteriorly, disappearing well anterior 

 to terminal portion; fixed lateral spines relatively 

 short, their length 0.7-0.8 basal width of terminal 

 portion; latter broad, length 2.5-3.3 times basal 

 width; mesial ramus of uropod overreaching apex 

 of telson by as much as 0.2 of its own length; 

 lateral ramus conspicuously surpassing mesial, 

 and armed with small distolateral spine, slightly 

 projecting beyond contiguous distal margin of 

 ramus. 



Petasma (Figure 51A, B) cincinnulate along 

 proximal 0.6 of median line; broad distal part of 

 ventromedian lobule strongly produced into elon- 

 gate, distally directed distomesial projection, 

 and short distolateral projection, and with ter- 

 minal margin spinulous; distal part of ventro- 

 lateral lobule heavily sclerotized, forming plate 

 with border undulate adjacent to ventral costa, 

 its terminal portion subrectangular, strongly 

 inclined toward, and partially covered by, ventro- 



FIGURE 51.— Hadropenaeus modestus, 6 16.5 mm cl, southeast of Cape Fear, N.C. A, Petasma (partly bent laterally), dorsal view of 

 right half. B, Ventral view. C, Right appendices masculina and interna, dorsal view. D, Ventromesial view. 



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