« Previous Species | Next Species » | Photos
Ebony Jewelwing



Search For More Images

Calopteryx maculata

Palisot, 1805


Order Odonata
Suborder Zygoptera
Superfamily Calopterygoidea
Family Calopterygidae
Genus Calopteryx
Species maculata (Palisot, 1805) [Agrion]


Identification

This is a common, large, black species, widely distributed in the eastern part of the region. The head is iridescent blue-green. The thorax is black with strong iridescent blue-green coloration dorsally and on the sides. Males lack a pterostigma. Older, mature males have solid black wings, while wings in teneral individuals are lighter and brown in color. Wings of females are usually paler, becoming progressively darker apically with a conspicuous white pterost igma (enclosing numerous cells ) that is distinctively widened at middle. Length of wings is about three times their greatest width. The abdomen is iridescent blue-green dorsally, black ventrally, except for a white (males ) or brown (females ) area on the posterior of sterna 8 and segments 9 and 10.

Size

Total length: 37-57 mm; abdomen: 30-47 mm; hindwing: 25-37 mm.

Similar Species

Smoky Rubyspot (Hetaerina titia ) is the only other damselfly that may have completely dark wings. It lacks the blue-green iridescence on the body and the wings are only about a fifth as wide as long. In Sparkling Jewelwing (C. dimidiata ) only the apical fourth of the wings are black.

Habitat

Small, slow moving, canopy covered streams and occasionally exposed streams and rivulets.

Discussion

This species ranks among the most studied of damselflies in North America. Nymphs are local in occurrence and restricted to slow creeks and quiet areas of running streams. The primary factors affecting their distribution within streams are rate of flow, depth of water and type of vegetation present while, adults occur along a wide variety of stream-riverine conditions and often disperse well away from water. Males will vigorously compete among themselves for territories with submergent vegetation, the prime egg-laying habitat for females. Males attract females with a "cross display," where the male faces the female with his hindwings deflected downward at right angles to his body, and the forewings and abdomen are raised, revealing the ventral pale area of the abdomen. The major ity of mating and egg laying occurs in the early afternoon and a single male may guard multiple females, resulting in sometimes large congregations. Females will lay their eggs in submergent vegetation for 10 to 120 minutes and usually don't submerge themselves. The displays and behaviors of northern and southern populations may differ. For a summary of these behaviors the reader is directed to Dunkle (1990). Female Ebony Jewelwing has been reported to use her ovipositor to steady herself on a leaf while feeding on a mayfly.

Distribution

Eastern North America including Canada; westward to Wisconsin and south to Texas.