FISHERY BULLETIN: VOL. 83, NO. 1 



margin, i.e., anterior, opposite, or posterior to 

 hepatic spine; 2) middle tooth, largest of three, 

 placed between 0.34 and 0.48 (mean 0.42) cl from 

 orbital margin; and 3) posterior tooth, positioned 

 well in advance of posterior margin of carapace, 

 between 0.64 and 0.73 (mean 0.70) cl from orbital 

 margin. Antennal spine absent, antennal angle 

 broadly obtuse or rounded; hepatic spine long, 

 sharply pointed, projecting from low buttress, and 

 positioned between 0.20 and 0.30 (mean 0.25) cl 

 posterior to orbital margin. Postocular sulcus 

 short; hepatic sulcus shallow, subhorizontal; hepa- 

 tic carina lacking; branchiocardiac carina at most 

 barely evident. 



Eye (Fig. 15A) with ocular calathus broad and 

 bearing conspicuous tuft of setae on dorsolateral 

 extremity; ratio of length of lateral margin to 

 width (across base of cornea) 0.50-0.60 (mean 0.54) 

 and ratio length of lateral margin to carapace 

 length 0.08-0.13 (mean 0.11). 



Antennular peduncle with stylocerite produced 

 in acute spine reaching 0.65-0.85 of distance be- 

 tween lateral base of first antennular article and 

 mesial base of distolateral spine; latter extending 

 to proximal 0.45 of second antennular article. An- 

 tennular flagella short, mesial one about 0.8 as 

 long as lateral; latter about 0.4 cl. 



Scaphocerite reaching between midlength and 

 distal end of third antennular article; lateral rib 

 produced in long, slender spine conspicuously 

 overreaching lamella. Antennal flagellum as 

 much as 3 times as long as carapace. 



Third maxilliped much stouter than pereopods. 

 Basis and ischium of first pereopod each armed 

 with well-developed sharp spine. 



Figure 15.— Eyes. A, Sicyonia disparri, ? 9 mm cl, NW of 

 Mantanchen, Nayarit, Mexico. B,S. parri (Burkenroad), j 10.5 

 mm cl, east side of Cocoa Point, Barbuda. Dorsal views. Scale 

 = 1 mm. 



Abdomen with dorsomedian carina low an- 

 teriorly, increasing in height posteriorly; carina 

 on first somite produced in rather small, an- 

 teriorly directed tooth, usually smaller than pos- 

 terior tooth on carapace; carina on second somite 

 conspicuously incised, and that on sixth terminat- 

 ing in short, sharp tooth. 



Anteroventral extremity of pleura of first three 

 somites rounded; pleuron of fourth with postero- 

 ventral margin straight to concave, its postero- 

 ventral extremity distinctly angular, occasionally 

 armed with minute tooth; posteroventral extrem- 

 ity of fifth and sixth somites produced in very 

 small, caudally directed, sharp tooth. 



First somite traversed by long, sometimes inter- 

 rupted, deep anteromedian pleural sulcus ending 

 well above ventral margin without meeting long, 

 united posterior tergal-posteromedian pleural 

 sulci. Second and third somites marked by 1) long 

 anterior tergal sulcus and relatively short pos- 

 terior tergal sulcus; 2) anteromedian pleural sul- 

 cus, extending almost to ventral margin on second 

 somite but restricted to dorsal part on third, in 

 both somites delimiting anterior shallow depres- 

 sion setting off rounded prominence dorsally; and 

 3) posteromedian pleural sulcus, its dorsal ex- 

 tremity curving anteriorly, ventral to (not joining) 

 posterior tergal sulcus. Fourth and fifth somites 

 with anterior tergal sulcus (that of fourth usually 

 obliterated at about midlength) fused with united 

 posterior tergal-posteromedian pleural sulci. 

 Sixth somite marked by strongly arched pos- 

 teromedian pleural sulcus and bearing shallow, 

 longitudinal depression between dorsolateral 

 ridge and elongate, often ill-defined cicatrix. 



Telson with pair of short but well-developed 

 fixed spines and two longitudinal rows of movable 

 spinules on either side of densely setose median 

 sulcus — mesial row extending almost to base of 

 spine. Both rami of uropod almost reaching or 

 barely overreaching apex of telson. 



Petasma (Figs. 5, 16A, B) with cornified distal 

 projection of dorsolateral lobule bulbous prox- 

 imodorsally, curved mesially, and minutely bifid 

 distally; fleshy distal projection of ventrolateral 

 lobule directed distolaterally, expanded basally 

 and with slender but blunt terminal part slightly 

 curved proximally. Lateral margin of petasma 

 conspicuously notched just proximal to mid- 

 length, forming shoulder immediately proximal 

 to notch. 



Petasmal endopods coupled in males with 

 carapace length as little as 3 mm (about 13 mm tl) 

 but sometimes unjoined in individuals with 



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