FISHERY BULLETIN: VOL. 69, NO. 3 



of anteniial carina; branchial region covered 

 with short setae; pair of small, bare, crescent- 

 shaped to semicircular areas- at anterior end of 

 posterior third of carapace, flanking postrostral 

 carina. Abdomen naked, except for elongate 

 patches of long setae on each side of mid-dorsal 

 carina on third to sixth somites, and two addi- 

 tional paired patches often present on sixth so- 

 mite, one dorsal and other ventral to cicatrices. 

 Telson (Figure 3A) with two pairs of longitudi- 

 nal bands of long setae, one along walls of median 

 sulcus, and other along lateral sulci. 



Rostral teeth 6-7, first tooth situated imme- 

 diately behind orbital margin; epigastric tooth 

 at posterior end of anterior fourth of carapace. 

 Rostrum reaching as far as proximal fourth of 

 dorsal flagellum; basal portion ascending well 

 above level of carapace, and apical one-third, un- 

 armed portion, decreasing progressively in 

 height, and curving upward. Adrostral carina 

 slightly sigmoidal, ending about midway between 

 first rostral and epigastric tooth. Postrostral 

 carina strong, long, reaching almost to posterior 

 margin of carapace, higher anteriorly, bearing 

 elongate fossette, immediately behind midlength, 

 and several pits posteriorly. Orbital angle pro- 

 duced into rather broad orbital spine. Gastro- 

 orbital carina and orbito-antennal sulcus absent. 

 Postocular sulcus deep, extending posterovent- 

 rally to about level of orbital angle. Longitudinal 

 suture well marked, long, extending along two- 

 thirds of carapace or slightly more. Ti'ansverse 

 suture short, clearly distinct, situated at level 

 of coxa of third pereiopod. Antennal and hepatic 

 spines long and strongly acuminate. Antennal 

 carina prominent, extending to below hepatic 

 spine. Cervical sulcus shallow and short, not in- 

 tercepting longitudinal suture. Hepatic carina 

 and hepatic sulcus well marked, and inclined 

 anteroventrally, their length about one-third that 

 of carapace. Postcervica! line sinuous, extend- 

 ing from postrostral carina to near posterior end 

 of hepatic carina. Branchiocardiac sulcus feeble, 

 marked ventrally by obtuse carina. Pterygosto- 

 mian angle obtuse, its ventral margin sloping 

 posteroventrally before turning backwards. 



Antennular flagella subequal, shorter than 

 either antennular ])eduncle or carajiace, slightly 

 longer in males than in females of same length, 



and proportionally longest in subadult; ratio of 

 flagellar length to carapace length about 0.66 in 

 shrimp of 1.5 mm carapace length, ratio decreas- 

 ing with increasing length of shrimp to about 

 0.40 in shrimp with carapace length of 40 mm. 

 First .'egment of antennular peduncle with disto- 

 median boi'der produced into heavy, scalelike 

 projection densely covered with long setae; dis- 

 tolateral spine prominent, slender and sharp; 

 prosartema long, extending to distal end of seg- 

 ment; stylocerite attaining midlength of seg- 

 ment. 



Antennal flagellum long, almost twice total 

 length of shrimp; scaphocerite reaching distal 

 end of antennular peduncle, elongate, its length 

 2'/-; times maximum width; lateral, thickened 

 margin ending anteriorly in strongly pointed 

 spine. 



Third maxilliped surpassing carpocerite by as 

 much as dactyl and one-fourth of propodus; first 

 pereiopod reaching, at most, base of carpocerite; 

 second pereiopod surpassing distal end of car- 

 pocerite by as much as three-quarters of dactyl; 

 third pereiopod exceeding carpocerite by as much 

 as projiodus and one-tenth of carpus; fourth per- 

 eiopod extending to about same level as first; fifth 

 pereiopod very long and slender, exceeding car- 

 pocerite by entire length of dactyl, and surpass- 

 ing fourth by projiodus and four-fifths length of 

 carpus. Spine on basis of third maxilliped, and, 

 as in all members of genus, on first and second 

 pereipods. Epipodites on first and second 

 pereiopods deeply bifurcate, epipodites on second 

 maxilliijed and third pereiopod unfurcate; ves- 

 tigial anterior arthrobranchia on somite XIII. 



Abdomen with middorsal carina extending 

 from posterior half of second to sixth somite, 

 carina low and rounded on second, rather acute 

 on third, and forming high and sharp keel from 

 fourth to sixth somites; fourth and fifth somites 

 with ])osteromedian V-shaped notch; sixth so- 

 mite bearing middorsal spine posteriorly, small 

 spine at posteroventral angles, and two cicatrices 

 on each side, anterior one sensibly longer. Telson 

 (Figure 3A) shorter than inner ramus of uropod, 

 with median sulcus deep anteriorly and well 

 marked posteriorly to base of terminal portion; 

 paired rounded carinae flanking median sulcus, 

 and sharp carinae bordering oblique, lateral 



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