24-8-2024 RIO SERPIS GANDIA, VALENCIA - NOMAD DRAGONFLY (MALE) (Sympetrum fonscolombii)

The red-veined darter or nomad (Sympetrum fonscolombii) is a dragonfly of the genus Sympetrum.

Sympetrum fonscolombii was named under the protonym Libellula fonscolombii by the Belgian entomologist Edmond de Sélys Longchamps, in 1840, in honor of the French entomologist Étienne of Fonscolombe (hence the species name). Its name is sometimes spelt fonscolombei instead of fonscolombii but Askew (2004) gives the latter as the correct spelling.

Sympetrum fonscolombii can reach a body length of 38–40 millimetres (1.5–1.6 in). This species is similar to other Sympetrum species but a good view with binoculars should give a positive identification, especially with a male.

Males have a red abdomen, redder than many other Sympetrum species. The frons and the thorax are red-brown. The eyes are brown above and blue/grey below. The wings have red veins and the wing bases of the hind-wings are yellow. The pterostigma is pale yellow with a border of black veins.

Female are similar but the abdomen is ochre yellow, not red, with two black lines along each side. The wings have yellow veins at the costa, leading edge and base, not red veins as found in the males. The legs of both sexes are mostly black with some yellow.

Immature males are like females but often with more red and a single line along each side of the abdomen.

Male S. fonscolombii can be mistaken for Crocothemis erythraea as both are very red dragonflies with yellow bases to the wings, red veins and pale pterostigma. However C. erythraea has no black on the legs, a broader body and no black on the head. Also C. erythraea females do not oviposit in tandem. The gestalt image of these two species is different and with some experience are easy to tell apart.