FISHERY BULLETIN: VOL. 77. NO, 4 



second article and proximal 0.2 of third). Third 

 pereopod of male overreaching antennular 

 peduncle by as much as length of dactyl, that of 

 female, by propodus. Fourth pereopod surpassing 

 carpocerite by length of dactyl or by a maximum 

 of dactyl and propodus. Fifth pereopod exceeding 

 antennular peduncle by dactyl or by latter plus 

 0.4 length of propodus. Order of pereopods in 

 terms of their maximum extensions: first, fourth, 

 second, fifth, and third; fourth pereopod extend- 

 ing almost as far as second, and fifth almost as far 

 as (occasionally farther than) third. 



Abdomen with sixth somite elongate, about 1.7 

 times maximum height, bearing rather prominent 

 interrupted cicatrix on lateral surface. Telson 

 (Figure 21C) with lateral margins bearing three 

 pairs of short movable spines; fixed spines moder- 

 ately long, extending at most as far as base of 

 distal third of terminal portion; terminal portion 

 (Figure 2LD) with length 6-8 times basal width, 

 fiasklike in shape, its lateral margins convex or 

 forming widely obtuse angles anteriorly, converg- 

 ing posteriorly, and with dorsal surface subplane. 

 Mesial ramus of uropod reaching apex of telson or 

 overreaching it by as much as 0.20 of its own 

 length; lateral ramus overreaching mesial by 

 about 0.25 of its own length. 



Petasma (Figure 22A, B) with dorsomedian 

 lobule produced into rather broad distomedian 

 projection, and bearing elongate distal plate and 



broader, subtriangular proximal plate raised 

 mesially in low, sometimes sharp crest; rib of dor- 

 solateral lobule terminating proximally in subcir- 

 cular process. Ventrolateral lobule with distolat- 

 eral portion broadly rounded, bearing distally 

 rather flexible and translucent marginal region, 

 strongly reflexed inwardly; distal part of ventral 

 costa curving abruptly dorsomesially at about 

 right angle, and ending in short, relatively narrow 

 process (free from, though closely appressed to, 

 margin of dorsolateral lobule) reaching approxi- 

 mately to level of cincinnuli. 



Appendix masculina (Figure 22C) considerably 

 broader than long (width 1.7-2.0 length), roughly 

 kidney-shaped; band of relatively long setae ex- 

 tending around free margin, broadening and 

 forming patch mesially, or setae covering more 

 than half of dorsal surface. 



Thelycum (Figures 23; 24A, B) with anterior 

 border of plate of sternite XIV transverse or 

 slightly inclined posterolaterally, almost straight 

 or somewhat sinuous on each side of posteromedi- 

 an projection of sternite XIII, and forming almost 

 right angle with lateral borders. Plate (produced 

 anteriorly in paired small submesial lobules), 

 densely setose laterally, strongly slanting dor- 

 somesially toward deep, usually narrow, subme- 

 dian depressions; median ridge of variable length, 

 broadening and much higher posteriorly, usually 

 appearing flask-shaped, its bulbous portion cov- 



FlGURE 22. — Penaeopsis rectacuta, -i 17.5 mm cl, Singapore. A, Petasma, dorsal view. B, Ventral view. C, Right appendix masculina, 



dorsal view. Scale = 1 mm. 



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