119 

 Smith and Pritchard: Odonafa 



' Fig. 4:24. Gomphus confraternus confraternus. a,c, vulva; b, 

 f ateral view of male abdominal appendages; d, second abdominal 



egment of male; e, dorsal view of male abdominal appendages; 



female occiput; g, ventral view of male abdominal appendages; 



L color pattern of male; i, color pattern of female (Kennedy, 



917). 



twice the length of segment 10 (fig. 4:276) 



intricatus Hagen 



- Segment 9 with a minute middorsal spine at apex; anal 



appendages equal to segment 10 (fig. 4:27a) 



olivaceous Selys 



Family AESHNIDAE 



Adults belonging to the family Aeshnidae are large, 

 obust, and strong flying dragonflies. They are com- 

 nonly seen over ponds or lakes, feeding on swarming 

 nsects, and many species roam far from water, even 

 nto cities and buildings. Most of the group are diur- 

 tal, but a few species are crepuscular in flight. 



The female has a well-developed ovipositor that 

 she inserts into succulent stems of aquatic plants 

 for oviposition. Most species breed in the quiet water 

 )f lakes or along the margins of slow flowing streams. 



The naiads possess a smooth, elongate body with 

 ong thin legs. They are active and clamber over the 

 iquatic vegetation and bottom trash, sometimes paus- 

 ing to stalk their prey. Almost any living animal that 



they can capture is eaten, even small fish, and the) 

 are also notoriously cannibalistic. 



Many of the genera found in North America are 



indigenous to the eastern United States or else the) 

 are primarily tropical in distribution. Only four genera 

 are known to occur in California, a fifth genus, Oplonr 

 aeschna, occurs in the neighboring slate of Arizona. 



Key to Nearctlc Genera 

 Adults 



1. Arculus with upper sector shorter than lower e< tot 

 (fig. 4:28) Anax Leach 



— Arculus with upper sector as long as or longer than 

 lower sector (figs. 4:29; 4:33) 2 



2. Basal space with 2 or more cross veins 



3 oyer i n Mac I ..uhlan 



— Basal space with not more than a single cross vein 



3 



3. Radial sector simple 4 



— Radial sector forked; stigma surmounting 3 or more 

 cross veins not counting brace vein (fig. 4:29) 6 



4. Stigma surmounting 1 cross vein not counting brace 

 vein; supratriangle without cross veins 



Gomphaeschna Selys 



rnrr^Q gyTn* 



TTT^T?BH3> 



Fig. 4:25. Color patterns in the genus Gomphus. o-c, G. 

 intricatus; d-g, G. olivaceous (Kennedy, 1917). 



