Calopteryx dimidiata

Burmeister, 1839

Sparkling Jewelwing

Calopteryx dimidiata, commonly known as the sparkling jewelwing, is a small to the eastern and southeastern United States. It is one of the smallest members of the Calopterygidae, measuring 37–50 mm in length. The species inhabits sandy forest streams with fast-flowing water, particularly acidic streams with abundant riverside vegetation. are active from spring through autumn depending on latitude, with males defending small territories and engaging in ritualized courtship .

Calopteryx dimidiata 31166030 by Judy Gallagher. Used under a CC BY 4.0 license.

Nature neighbors (Plate 646) (6276932440) by Abbott, Gerard Alan.; Banta, Nathaniel Moore; Higley, William Kerr; Schneider, Albert. Used under a Public domain license.

Nature neighbors - Calopteryx dimidiata by Abbott, Gerard Alan.; Banta, Nathaniel Moore; Higley, William Kerr; Schneider, Albert. Used under a Public domain license.

Pronunciation

How to pronounce Calopteryx dimidiata: /kæˈlɑptərɪks dɪˌmɪdiˈɑːtə/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Distinguished from sympatric Calopteryx by: (1) male wings with black band terminating in straight line to nodus (not curved or irregular), (2) forewings and hindwings subequal in size (difference ≤2 mm), and (3) black sternum on tenth abdominal segment. These features separate it from C. maculata and other in its range. Females are more difficult to identify due to variable wing pigmentation and require examination of associated males or detailed morphological study.

Images

Appearance

Total length 37–50 mm. and long slender metallic bluish-green; brown. Males: terminal fifth of each wing black with straight line separating dark section from transparent hyaline remainder; forewings and hindwings differ in size by no more than 2 mm; sternum of tenth abdominal segment black. Females: slightly more bronzy-green; wing pigmentation variable—may resemble male pattern but less defined, or only hindwings tipped with black, or wings entirely clear; small white pterostigma usually present near wing tip. Immatures: reddish eyes, duller coloration overall.

Habitat

Sandy forest streams with fast-flowing water, particularly acidic streams; requires locations with plentiful riverside vegetation. Found in woodland and open areas near forest rivers and streams.

Distribution

to eastern and southeastern United States. Range extends from New England to Louisiana and parts of Texas, primarily on the Atlantic coastal plain.

Seasonality

on wing May–September in New Jersey; February–November in Florida. Activity period varies with latitude, with longer season in southern portions of range.

Behavior

Males patrol small territories near breeding sites, circling and chasing off rivals. Ritualized courtship precede copulation when female present. Copulation lasts approximately two minutes. Female oviposits by down stem of emergent plant and remaining underwater approximately fifteen minutes to lay batch of several hundred before returning to surface. Both sexes often observed together near breeding sites.

Similar Taxa

Calopteryx maculataOverlapping range; distinguished by male wing band with curved or irregular margin and different wing size proportions
Calopteryx aequabilisSympatric in some areas; larger size and different wing pigmentation pattern

More Details

Taxonomic history

has been subject of taxonomic study examining morphological variability across its range; some geographic variation in wing pigmentation patterns documented

Conservation status

NatureServe records indicate is tracked for conservation status; specific rank not detailed in available sources