Hemigomphus heteroclytus - Stout Vicetail

Male identification: A robust yellow and black dragonfly with paired, conjoined paired white spots along the top of the abdomen and large pale claspers at the tip. Last three segments swollen so tail is clubbed. Usually perches with tail slightly elevated and arched. Upper thorax with variable patterning but antehumeral commonly joined to collar. Single isolated and prominent black spot near top of intersegmental suture on side of thorax.

Female identification: Unknown. Assumed to be similar to female gouldii.

Similar species: Extremely similar to gouldii. Field separation characteristics are only postulated at this stage. Gouldii appears to differ by having an indistinct and often absent isolated black spot on the intersegmental suture. Clubbed tail is also less heavy, with segment 7 only gently tapering in size (in heteroclytus segment 7 doubles in width). gouldii also appears to have largely separated paired spots on the upper abdomen, particularly on segment 2. On heteroclytus, the spots are joined over the mid-dorsal line of the abdomen.

Behaviour: Readily perches on rocks and flies low and fast over water.

Distribution: May be confined to northeast Victoria, north of the Alps. Has been recorded in Middle Creek and the Mitta Mitta River. Only recorded at altitudes less than 400m.

Australian State distribution (from CSIRO Entomology)

Habitat: Wide, relatively fast flowing rocky rivers with riffles.

Status: Uncommon and localised

Flight period: December to February