Polyoelis aoronata brevipenis new subspecies 



Synonym: Polycelis ooronata: Hyman, 1931. 



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Fig. 19 after Kenk (1952). 



Externally indistinguishable from the subspecies aoronata, differing 

 from it chiefly in the anatomy of the copulatory apparatus. 13-20 mm 

 long when mature. The penis bulb is very large and elongated, the penis 

 papilla short, plug-like. The penial cavity or seminal vesicle is volum- 

 inous, stretched out in the longitudinal axis, and receives the two sperm 

 ducts laterally, often asymmetrically. The ejaculatory duct is rather 

 wide and short. The bursal canal, which lies on the left side of the 

 penis, has a wide anterior portion which is lined with a glandular epi- 

 thelium similar to that lining the bursal sac. Where the duct turns 

 downward at the level of the male atrium, its histological nature changes 

 abruptly. The epithelium becomes nonglandular and the duct acquires a 

 strong muscle coat (this division of the bursal duct into an anterior 

 glandular and a posterior muscular part is seen also in the subspecies 

 ooronata but not in borealis) . Reproduction sexual and by fission. Re- 

 ported from South Dakota and Colorado, but is probably more widely 

 distributed. Literature: Hyman (1931a), Kenk (1952). 



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