152. 



122, Ovary one monohystGra de Han, 1880 (r;) 



Ovaries two 123 



123. Tails shorter than anal body diameter 



paraobtusicaudatus Micol., 1922 (s) 



Tails longer than anal body diameter I2I4 



I2U. Spear aperture less than half the spear length 



pratensis de Man, I88O (s) 



Spear aperture three-fourths the spear length 

 minutus Butschli, 1873 (s) 



125. Tails uniformly conoid 126 



Tails bluntly convex-conoid to hemispherical Iii5 



126. Length about 1.0 mm, or less 127 



Length about 1,$ mm. or more 133 



127. Spear length three to four times width of lip region 128 



Spear length less than twice width of lip region 129 



128. Spear length three times width of lip region 



penetrans Th. & Swang,, 1936 (s) 



Spear length four times width of lip region 



microdorus de Man, I88O (s) 



129. Width under 3.0% brevidens Th. & Swang,, 1936 (s) 



Width i;,0-^— 6.0^ 130 



130. Spear length three-fourths width of lip region 



diminutivus Th. & Swang., 1936 (s) 



Spear length equal to or longer than width of lip region .... 131 



131. Spear aperture occupying one-seventh the spear length 



bryophilus de Man, I88O (s) 



Spear aperture occupying one-third or more of the spear length. , 132 



132. Lips rounded miser Th, & Swang,, 1936 (s) 



Lips angular productus Th. & Swang., 1936 (s) 



133. Lip region continuous with neck contour 13l| 



Lip region distinctly set off 135 



I3U. Spear about one-fourth as wide as lip region 



angus tic ephalus Steiner, 1911; (s or a) 



Spear about one-ninth as wide as lip region 



frigidus Steiner, I9I6 (s) 



135. Length well over 3.0 mm I36 



Length 2.5 mm. or less I38 



136, Neck constricted posterior to spear .... labiatus de Man, I88O (s) 

 Neck not constricted posterior to spear 137 



