Dugesia antillana Kenk, 1941 



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-K 



14 



III 'I 

 III .' I 



pb pp am ac ^p 



Fig. 14 after Kenk (1941). 



Very slender, up to 19 mm long and 0.7 mm wide. Head triangular, rather 

 broad, with long, pointed auricles. Dorsal side grayish-brown, sometimes 

 with an indistinct darker streak in the prepharyngeal midline, ventrally 

 somewhat lighter. Eyes usually two, lying close together. The two eye 

 fields, the auricles and a spot at the site of the gonopore lack pigment. 

 Pharynx pigmented. Testes numerous, predominantly dorsal, starting 

 behind the ovaries and extending to near the posterior end. At full ma- 

 turity, some testes may occupy the entire dorsoventral diameter. Vasa 

 deferentia expand at the level of the mouth into spermiductal vesicles, 

 then narrow again as they approach the penis. The gonopore leads into 

 a common atrium which dorsal ly receives the bursal duct and anteriorly 

 connects with the male atrium. Penis with rather small bulb and short, 

 conical papilla. The vasa deferentia enter the bulb dorsolaterally and 

 widen within the bulb into a pair of spindle-shaped cavities which unite 

 in the papilla to a short canal, the ejaculatory duct, which opens at 

 the tip of the papilla. Close to the union of the two sperm ducts, a 

 pair of tubular diverticula extend toward the penial bulb (very charac- 

 teristic of the species). Copulatory bursa voluminous, bursal stalk 

 running dorsal to the penis and bending ventrally behind it to approach 

 the common atrium. Oviducts open separately into the bursa stalk. Below 

 their opening, the stalk receives numerous eosinophilic shell glands. 

 Inhabits mountain streams. Only sexual reproduction has been observed. 

 Known only from Puerto Rico. Literature: Kenk (1941). 



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