PEREZ FARFANTE: SPERMATOPHORES OF AMERICAN WHITE SHRIMPS 



Figure 14.-Penaeus (Litopenaeiis) schmitti. A, Ventrolateral view of right spermatophore dissected 

 from terminal ampulla,<?off Ubatuba, Sao Paulo, Brasil, B, Dorsomesial view of same specimen. 



plate and a submarginal thickness somewhat stif- 

 fens the entire flap. A glutinous material rests 

 against the flange, and adheres to the mesial sur- 

 face of the flap. 



The thin, translucent dorsomesial wall bulges 

 conspicuously beyond its attachment along an 

 oblique line extending from the anterior 

 extremity of the mesial lapel to the postero- 

 proximal end of the wing (Figure 14B; this bulge, 

 occupied by the extremity of the sperm mass 

 enclosed in the spermatophore, bears a triangular 

 crest, rather similar to the subconical anterior 

 extremity of the sperm sac in P. stylirostris. 

 Posterior to the bulge, the dorsomesial wall, as in 

 all the other spermatophores, is attached to the 

 mesial lapel along its entire length, extending 

 laterally to join the blade, and caudally to become 

 aflixed to the base of the flange. 



The wing is long and irregular in contour, 

 produced caudally in a broad proximal lobe, and 

 tapers to a rounded excavated tip. The ventral 

 surface is scabrous, bearing several projections: a 

 rigid, rounded prominence on the anterior rib; an 

 elongate, twisted process (its base situated 

 slightly distal to midlength) that extends mesially 

 in the form of a subovate to nearly semicircular 

 lobule; and a distal shelf, obliquely flanking the 

 process posterolaterally. 



The dorsal plate (Figure 14B) is roughly tear- 



shaped, rounded anteriorly, tapering posteriorly, 

 and relatively long, extending from the anterior 

 end of the blade (at the base of the wing) almost to 

 its posterior tip. The plate is intimately associated 

 with the blade anteriorly, and practically fused to 

 the flange posteriorly. 



Thelycum (Figure 15) 



Sternite XIV bears a pair of subparallel 

 anterolateral ridges which extend posteriorly 

 without turning mesially, to reach two rigid 

 rounded or subconical prominences; a narrow 

 median sulcus often divided by a slender longi- 

 tudinal rib is present anterior to the prominences. 

 Sternite XIII is rigidly sclerotized forming a 

 strong plate produced posteriorly as an emar- 

 ginate soft shelf overhanging sternite XIV; the 

 anterior part of this sternite bears a pair of soft 

 and naked transverse elevations flanking a 

 tonguelike lamella bordered by setae. The lamella 

 forms the roof of a concavity floored by a strong 

 ridge from sternite XII. The ridge (a marginal 

 thickening of platelike sternite XII and mostly 

 hidden by setose, rounded, and relatively short 

 coxal plates of the third pereopods) is produced 

 into two pairs of convex projections, a small 

 median pair and considerably larger lateral ones 

 armed with long setae. The concavity of sternite 



477 



