Somatochlora


Somatochlora, or the striped emeralds, is a genus of dragonflies in the family Corduliidae with 44 described species found across the Northern Hemisphere.

Taxonomy

The name Somatochlora is derived from the Greek soma and khloros. The species Corduliochlora borisi was formerly treated as a member of Somatochlora.

Description

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.

Distribution

Somatochlora 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 of up to 3700 metres. In North America, most species live in the boreal forest and/or Appalachian mountains.

Life History

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.

Species

Somatochlora is the most diverse group within the Corduliidae. Of the 44 described species listed below, 25 are North American, 18 are Eurasian, and 1 is circumboreal.
SpeciesCommon NameDistribution
Somatochlora albicincta ringed emeraldCanada, northern United States
Somatochlora alpestris alpine emeraldEurope and Asia
Somatochlora arctica Northern emeraldEurope and Asia
Somatochlora brevicincta Robert, 1954Quebec emeraldCanada, northern United States
Somatochlora calverti Williamson & Gloyd, 1933Calvert's emeraldsoutheastern United States
Somatochlora cingulata lake emeraldCanada, northern United States
Somatochlora clavata Oguma, 1922Japan and Korea
Somatochlora daviesi Lieftinck, 1977Meghalaya
Somatochlora dido Needham, 1930China and Vietnam
Somatochlora elongata ski-tipped emerald, ski-tailed emeraldnortheastern North America
Somatochlora ensigera Martin, 1907plains emeraldcentral North America
Somatochlora exuberata Bartenev, 1910Japan and eastern Russia
Somatochlora filosa fine-lined emeraldsoutheastern United States
Somatochlora flavomaculata yellow-spotted emeraldEurope
Somatochlora forcipata forcipate emeraldCanada, northern United States
Somatochlora franklini delicate emeraldCanada, northern United States
Somatochlora georgiana Walker, 1925coppery emeraldeastern United States
Somatochlora graeseri Selys, 1887east Asia
Somatochlora hineana Williamson, 1931Hine's emeraldOntario and Midwest United States
Somatochlora hudsonica Hudsonian emeraldwestern and central Canada, northwestern United States
Somatochlora incurvata Walker, 1918incurvate emeraldnortheastern North America
Somatochlora kennedyi Walker, 1918Kennedy's emeraldCanada, northeastern United States
Somatochlora linearis mocha emeraldeastern North America
Somatochlora lingyinensis Zhou & Wa, 1979Zhejiang
Somatochlora margarita Donnelly, 1962Texas emeraldTexas and Louisiana
Somatochlora meridionalis Nielsen, 1935Balkan emeraldsoutheastern Europe
Somatochlora metallica brilliant emeraldEurope
Somatochlora minor Calvert, 1898ocellated emeraldCanada, northern United States
Somatochlora nepalensis Asahina, 1982Nepal
Somatochlora ozarkensis Bird, 1933Ozark emeraldArkansas, Kansas, Missouri and Oklahoma
Somatochlora provocans Calvert, 1903treetop emeraldsoutheastern United States
Somatochlora sahlbergi Trybom, 1889treeline emeraldnorthwestern Canada, Alaska, northern Russia, Scandinavia
Somatochlora semicircularis mountain emeraldwestern North America
Somatochlora septentrionalis muskeg emeraldCanada
Somatochlora shanxiensis Zhu & Zhang, 1999Hubei, Shanxi
Somatochlora shennong Zhang, Vogt & Cai, 2014Guangxi, Hubei
Somatochlora taiwana Inoue & Yokota 2001Taiwan
Somatochlora tenebrosa clamp-tipped emeraldeastern North America
Somatochlora uchidai Förster, 1909Japan, China and Russia
Somatochlora vera Asia
Somatochlora viridiaenea Japan, eastern Russia
Somatochlora walshii brush-tipped emeraldCanada, northern United States
Somatochlora whitehousei Walker, 1925Whitehouse's emeraldCanada, northwestern United States
Somatochlora williamsoni Walker, 1907Williamson's emeraldeastern North America