Western Pondhawk
Erythemis collocata
Hagen, 1861
Order Odonata
Suborder Anisoptera
Superfamily Libelluloidea
Family Libellulidae
Genus Erythemis
Species collocata (Hagen, 1861) [Mesothemis]
Identification
This common, widespread, western species is similar to Eastern Pondhawk (E. simplicicollis simplicicollis). Its face and thorax are bright green in teneral
s and females. It has green eyes that become blue in older individuals (more so in males). The thorax and abdomen in older males turns completely powder blue or black with a waxy pruinescence. It has clear wings. Young males and females have abdominal segments 1-3 green and 4-10 paler yellowish-green with a black middorsal stripe from segments 2-9. The middle abdominal segments are broader than long and the caudal appendages are black. The female has a "scoop-like" ovipositor that projects ventrally.
Size
Total length: 39-42 mm; abdomen: 23-30 mm; hindwing: 30-33 mm.
Similar Species
Eastern Pondhawk is similar, but older males are paler blue with yellow or white cerci. Females have a more spotted abdomen and the middle abdominal segments in both sexes are narrower than their respective widths. Great Pondhawk (E. vesiculosa
) is larger and has complete black stripes or bands dorsally on abdominal segments 4-6, rather than spots. Snaketails (Ophiogomphus
) and Ringtails (Erpetogomphus
) all have the eyes separated on top of the head.
Habitat
Ponds, lakes and slow flowing waters of streams and creeks.
Discussion
This subspecies is considered a variant or western form of Common Pondhawk . Though many people consider it a valid species, there is evidence that suggests it intergrades with the eastern form. It is common in the extreme parts of the western Texas panhandle where it does occur with Eastern Pondhawk. Nothing has been written on what mechanisms may serve to identify these nearly identical species to each other where they occur together. Western Pondhawk is often seen perching on the ground similar to clubtails, for which they may be mistaken due to their green color. They are capable and fierce predators in the air, taking small to large prey at will.
Distribution
Western U.S. and Mexico.





