PEREZ FARFANTE: REVISION OF PENAEID SHRIMP GENUS PENAEOPSIS 



Figure 35— Penaeopsis sermta, 9 30 mm cl, N ofThunder Knoll, off Honduras. Sperm receptacles. A, Ventral view. B, Dorsal view 



(specimen stained). Scale = 2 mm. 



teromedian sinus. Receptacles opening through 

 long, paired slits located between sternites XIII 

 and XIV, and separated by narrow, shallow, an- 

 teromedian portion of sternite XIV. 



Stages in development of thelycum: in female 8 

 mm cl (Figure 36A), plate of sternite XIV bearing 

 median ridge produced anteriorly in long, sharp 

 spine not quite reaching sternite XIII; anterolat- 

 eral portions ventrally convex, covering invagina- 

 tions (seminal receptacles) from slitlike openings 

 along anterior margin of plate. Sternite XIII with 

 small triangular median plate produced in long, 

 sharp anteromedian spine reaching margin of 

 sternite XII. Sternite XII bearing minute, sharp 

 posteromedian tooth and pair of ridges extending 

 posterolaterally from base of tooth (tooth and 

 ridges changing little except increasing in size to 

 facies in adult). 



In female 9.5 mm cl (Figure 36B), plate of ster- 

 nite XIV with spine proportionately smaller than 

 that in few preceding instars, farther removed 

 from sternite XIII; anterolateral portions with 



openings of seminal receptacles enlarged and still 

 exposed. Sternite XIII with spine on median plate 

 distinctly overreaching sternite XII. 



In female 10.5 mm cl (Figure 36C), plate of ster- 

 nite XIV with median ridge virtually reaching 

 sternite XIII and bearing no more than rudiment of 

 spine; anterolateral portions overlapping sternite 

 XIII mesially, obscuring openings of sperm recep- 

 tacles, and frequently produced laterally in short 

 lobules, continuous with well-defined, exposed 

 hoods. Median plate of sternite XIII with spine 

 still slightly overreaching sternite XII. 



In female 12.5 mm cl ( Figure 36D), plate of ster- 

 nite XIV with elongate trapezoidal (usually be- 

 coming tear -shaped with increasing size) median 

 ridge, reaching sternite XIII; basal part of ridge 

 with strong median elevation; anterolateral por- 

 tions broadly overlapping sternite XIII and bear- 

 ing prominent lobules partly obscuring hoods. 

 Median plate of sternite XIII considerably 

 broadened, its anteromedian spine minute and 

 far removed from sternite XII; plate produced in 



755 



