150 



Smith and Pritchard: Odonata 



Fig. 4:88. Prothoraces of female Ischnvra. a, barberi; b, cer- 

 vula; c, perparva; d, denticollis; e, c/emorsa; i, ramburii (Celeste 

 Green). 



south to Mexico) (=extriata Calvert 1895) 



denticollis (Burmeister) 1839 



— Ventral appendage rounded, the dorsal branch projecting 

 dorsad (fig. 4:87d) (California) . .gemina (Kennedy) 1917 



3. Mesothorax with the antehumeral pale stripes repre- 

 sented only by widely separated spots (figs. 4:87/; 

 4:90a) (western U.S. and southwestern Canada, south 

 to Baja California and New Mexico) 



cervula Selys 1876 



— Mesothorax with antehumeral pale stripes complete 



4 



4. Ventral appendage widened and with 2-4 teeth distally 

 (fig. 4:876, e) 5 



— Ventral appendage with a single, slender branch (fig. 

 4:87a, c,.?) 6 



5. Prothorax medially emarginate on caudal margin; 

 abdominal segment 9 usually entirely blue (fig. 4:876) 

 (Montana and Colorado, south to Mexico City) 



demorsa (Hagen) 1861 



— Prothorax with hind margin convex medially; abdominal 

 segment 9 with a lateral black stripe (fig. 4:87e) 

 (British Columbia and western U.S., from Montana and 

 Colorado to Texas and California) 



perparva Selys 1876 



6. Ventral appendage with dorsal margin forming a very 

 large right angle (fig. 4:87<7); abdominal segment 10 

 with a pronounced dorsal development (British Columbia 

 to California) erratica Calvert 1895 



— Ventral appendage with dorsal margin forming at most 

 a small angulation (fig. 4:87a); abdominal segment 10 

 with a small dorsomedian development 7 



7. Ventral appendage with an obvious emargination dor- 

 sally, the tip directed dorsad (fig. 4:87a)(Utah, Colorado 

 New Mexico, Arizona) (=utahensis Muttkowski 1910) 



barberi Currie 1903 



— Ventral appendage without a dorsal emargination and 

 with the tip direct caudad (fig. 4:87c) (California, Baja 

 California to Central America, West Indies and Florida) 

 {-defixum Hagen 1861). . .ramburii credula (Hagen) 1861 



Fig. 4:89. Coloration of I schnura cervula. a, mature male; fa, 

 dark female; c,f, teneral dark female; d,e, teneral light female; 

 g, mature female (Kennedy, 1915). 



— Prothorax without a dorsomedian projection on caudal 



margin 2 



2. Prothorax with a dorsal projection on each mediolateral 

 lobe (fig. 4:88a*) 3 



cnxzzr 



azrn 



r r 



Fema les 



1. Prothorax with a dorsomedian angulation on posterior 

 margin, accompanied by pencils of incurved hairs from 

 each mediolateral lobe (figs. 4:886; 4:89) cervula 



Fig. 4:90. Coloration of Ischnura perparva, female, o-e, stages 

 in teneral coloration, i, intermediate stage between teneral and 

 adult coloration; g, adult coloration (Kennedy, 1915). 



