Dugesia dorotoaephata (Woodworth, 1897) 



Synonyms: Planaria dovotoaephala Woodworth, 1897; P. agilis Stringer, 1909; 

 Euplanaria dorotooephala: Kenk, 1930; E. agilis: Kenk, 1930; E. philadelphioa 

 Hyman, 1931; Dugesia agilis: Hyman, 1939; B. diabolis Hyman, 1956. 



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0.1 mm 



A polytypic species, in nature up to 30 mm long and about 3.5 mm wide 

 (may grow larger in laboratory cultures). Head triangular, with slightly 

 convex sides and rather pointed tip. A pair of elongated, sharply 

 pointed auricles extends laterally, during gliding usually held elevated. 

 Eyes normally two, close together, just anterior to the base of the 

 auricles. Color brown to almost black dorsally, somewhat lighter ven- 

 trally, occasionally with a darker middorsal streak behind the pharynx. 

 Under magnification small white and dark spots are seen on the general 

 background color. Pharynx pigmented light gray, with a short white tip. 

 Testes numerous, ventral, extending to posterior end. Penis with spher- 

 ical bulb and short conical or rounded papilla pointing posteroventrally. 

 Vasa deferentia enter bulb dorsolateral ly, bend down toward the axis of 

 the papilla, and increase in diameter, each duct forming a seminal vesi- 

 cle. Distal ly they unite to a short ejaculatory duct opening at the tip 

 of the papilla. Under certain conditions the two seminal vesicles may 

 appear fused, forming a larger, round vesicle. Bursal duct running pos- 

 teriorly above the penis, then curving ventral ly toward the small common 

 atrium. At the turning point it receives the two oviducts from the 

 posterolateral sides. Below these openings (which are close together) 

 is a short zone where numerous outlets of shell glands open into the 

 bursal canal (none into the oviducts) . Sexual or asexual reproduction 

 may predominate in different populations. Cocoon spherical, stalked. 

 Distributed in running and standing waters across the continent in the 

 United States and southern Canada. Principal literature: Woodworth 

 (1897), Hyman (1925, 1929, 1931b), Kenk (1944). 



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