Somatochlora, or the striped emeralds, is a genus of dragonflies in the family Corduliidae with 42 described species found across the Northern Hemisphere.
The name Somatochlora is derived from the Greek soma (body) and khloros (green). The species Corduliochlora borisi was formerly treated as a member of Somatochlora.
Members of this genus are medium-sized dragonflies with dark bodies and a metallic green lustre. The eyes are brilliant green, and many species have dull to bright yellow markings on the thorax and/or abdomen. The abdomens of males are distinctive, with the first two segments bulbous-shaped, the third constricted, and the rest of the abdomen club-shaped with a straight ending. Females have abdomens with straighter sides. Identifying these dragonflies to species can be difficult. The cerci of males, on the tip of the abdomen, are distinctively shaped in each species, as are the subgenital plates on female abdomens. In some species, the subgenital plate is large and projecting, and is used as a "pseudo-ovipositor" for inserting eggs into a substrate.
Somatochlora species are found across the Northern Hemisphere in Europe, Asia, and North America, with some species extending into arctic regions north of the treeline. Some species extend south to Spain, Turkey, northern India, northern Vietnam, Taiwan and the Southern United States. At least one species, S. semicircularis, may be found at altitudes up to . In North America, most species live in the boreal forest and/or the Appalachian Mountains.
Somatochlora larvae typically live in bogs, fens, and/or forest streams, with some species found in lakes. They do not occur in marshy ponds. Many species are limited to very specific habitats and are rare and local. Adults feed in flight and may occur at some distance from their breeding habitat in mixed swarms.
Somatochlora is the most diverse group within the Corduliidae. Of the 42 described species listed below, 25 are North American, 16 are Eurasian, and one is circumboreal (S. sahlbergi). Two additional fossil species have been assigned to this genus: S. brisaci, based on a wing from the Upper Miocene in France, and S. oregonica, based on two wings from the Oligocene in Oregon.
| Image | Species | Common Name(s) | Distribution | |
|---|---|---|---|---|
| Somatochlora albicincta | ringed emerald | Canada, northern United States | ||
| Somatochlora alpestris | alpine emerald | Europe and Asia | ||
| Somatochlora arctica | northern emerald | Europe and Asia | ||
| Somatochlora brevicincta | Quebec emerald | Canada, northern United States | ||
| Somatochlora calverti | Calvert's emerald | southeastern United States | ||
| Somatochlora cingulata | lake emerald | Canada, northern United States | ||
| Somatochlora clavata | Japan and Korea | |||
| Somatochlora daviesi | Bhutan, Nepal, and India | |||
| Somatochlora dido | China and Vietnam | |||
| Somatochlora elongata | ski-tipped emerald, ski-tailed emerald | northeastern North America | ||
| Somatochlora ensigera | plains emerald | central North America | ||
| Somatochlora exuberata | Japan and eastern Russia | |||
| Somatochlora filosa | fine-lined emerald | southeastern United States | ||
| Somatochlora flavomaculata | yellow-spotted emerald | Europe | ||
| Somatochlora forcipata | forcipate emerald | Canada, northern United States | ||
| Somatochlora franklini | delicate emerald | Canada, northern United States | ||
| Somatochlora georgiana | coppery emerald | eastern United States | ||
| Somatochlora graeseri | east Asia | |||
| Somatochlora hineana | Hine's emerald | Ontario and midwest United States | ||
| 120px | Somatochlora hudsonica | Hudsonian emerald | western and central Canada, northwestern United States | |
| Somatochlora incurvata | incurvate emerald | northeastern North America | ||
| Somatochlora kennedyi | Kennedy's emerald | Canada, northeastern United States | ||
| Somatochlora linearis | mocha emerald | eastern North America | ||
| Somatochlora lingyinensis | Zhejiang | |||
| Somatochlora margarita | Texas emerald | Texas and Louisiana | ||
| Somatochlora meridionalis | Balkan emerald | southeastern Europe | ||
| Somatochlora metallica | brilliant emerald | Europe | ||
| Somatochlora minor | ocellated emerald | Canada, northern United States | ||
| Somatochlora ozarkensis | Ozark emerald | Arkansas, Kansas, Missouri and Oklahoma | ||
| Somatochlora provocans | treetop emerald | southeastern United States | ||
| Somatochlora sahlbergi | treeline emerald | northwestern Canada, Alaska, northern Russia, Scandinavia | ||
| Somatochlora semicircularis | mountain emerald | western North America | ||
| Somatochlora septentrionalis | muskeg emerald | Canada | ||
| Somatochlora shanxiensis | Hubei, Shanxi | |||
| Somatochlora shennong | Guangxi, Hubei | |||
| Somatochlora taiwana | Taiwan | |||
| Somatochlora tenebrosa | clamp-tipped emerald | eastern North America | ||
| Somatochlora uchidai | Japan, China and Russia | |||
| Somatochlora viridiaenea | Japan, eastern Russia | |||
| Somatochlora walshii | brush-tipped emerald | Canada, northern United States | ||
| Somatochlora whitehousei | Whitehouse's emerald | Canada, northwestern United States | ||
| Somatochlora williamsoni | Williamson's emerald | eastern North America |