PEREZ FARFANTE: SPERMATOPHORES OF AMERICAN WHITE SHRIMPS 



A 



B 



C 



Figure 3.-Penaeus (Litopenaeus) vannamei. Left spermatophore dissected from terminal ampulla, <?off Juan Dfaz, Panami. A, 

 Ventrolateral view. B, Mesial view. C, Dorsolateral view (glutinous material removed). Abbreviations as in Figure 1. 



narrows anteromesially along the border of the 

 sac; posteriorly along the flange, it continues as a 

 flexible, but rather tough, narrow band. The flange 

 is long, directed caudally, with the anterior portion 

 marked by transverse wrinkles; a convex ridge 

 runs parallel and contiguous to the free mesial 

 margin along most of the entire length of the 

 flange, and its lateral margin bears the narrow 

 band from which a voluminous glutinous material 

 is suspended. The thin but rigid dorsomesial wall 

 (Figure 3B) is very broad basally and tapers 

 anteriorly where it is produced in a subconical 

 hood. 



The dorsal plate is long (Figure 3C), the longest 

 in the spermatophores of the five species, and at 

 the base of the flange is bent strongly dorsally, the 

 concavity thus formed delimiting two distinct 

 parts. The anterior part, firmly attached to the 

 dorsomesial wall, is nearly triangular in outline 

 and elevated in a blunt mesial ridge which ter- 

 minates anteriorly in a convex border at about the 

 level of the lateral furrow; the posterior part is 

 mostly flattened, and extends over the flange 

 reaching, or almost reaching, its posterior margin. 



The sperm mass, together with the gelatinous 



substance, is concentrated anteriorly in a large 

 subspherical protuberance filling the lateral bulge 

 and extends as a column in the posterior portion of 

 the sac. 



Thelycum (Figure 4A, B) 



Sternite XIV bears a pair of setose, sigmoid, 

 obliquely oriented anterolateral ridges, the lateral 

 portions of which are low and rounded and the 

 posteromesial portions high and sharp; the latter 

 are continuous caudally with short elevations 

 flanking a shallow central depression; sculpture is 

 lacking on the posterior part of the sternite. Ex- 

 tending ventrally from the platelike posterior part 

 of sternite XIII is a large, inverted, troughlike 

 median protuberance which forms the anterior 

 wall of a concavity bounded posteriorly by ridges 

 of sternite XIV; the posterior part of the sternite 

 XIII is also provided with a pair of small teeth, 

 subjacent to the base of the median protuberance, 

 and a pair of hornlike marginal projections lateral 

 to the protuberance. The anterior part of sternite 

 XIII bears two small setose lateral prominences, 

 located close to the margin which is overhung 



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