Polyoelis aoronata aoronata (Girard, 1891) 



Phagocata aoronata Girard, 1891. 



18 



0.5 mm 



ode bd 



ph m b 



Mature animals up to 19 mm long and 2.4 mm wide. Head truncate, with 

 convex frontal margin and a pair of triangular auricles with rounded 

 tips extending anterolaterally. Eyes multiple, irregularly scattered on 

 the dorsal side of the head in a band which parallels the margin of the 

 head, narrows posteriorly, and extends over the anterior quarter of the 

 prepharyngeal region. Dorsal side brown to almost black, ventral side 

 lighter. The individual eyes have no pigmentless fields. Testes ventral, 

 prepharyngeal. Penis with very muscular bulb and more or less conical 

 papilla, the size relations of the two parts being subject to great vari- 

 ation according to the state of contraction of the organ (generally the 

 papilla is as long as the bulb). The male atrium duplicates in shape the 

 penis papilla and receives in its posterior part the mouth of the common 

 oviduct. Bursa usually large, with a wide bursal duct proceeding back- 

 ward to one side (usually left) of the midline, lined with the same 

 glandular epithelium as the bursal sac and covered by a very feeble mus- 

 cle layer. Only in its posterior fourth the histological aspect of the 

 epithelial lining changes suddenly, the canal narrows, and its muscular 

 coat thickens. Reproduction sexual and asexual. Inhabits springs and 

 cold creeks in southern Wyoming, Utah, Montana, New Mexico. Principal 

 literature: Girard (1893), Braithwaite (1962). 



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