Ischnura aurora Brauer, 1865

Grand, Daniel, Marinov, Milen, Jourdan, Herve, Cook, Carl, Rouys, Sophie, Mille, Christian & Theuerkauf, Jörn, 2019, Distribution, habitats, phenology and conservation of New Caledonian Odonata, Zootaxa 4640 (1), pp. 1-112 : 25-27

Ischnura aurora Brauer, 1865

( Fig. 17 )

Agrion (Ischnura) aurora Brauer, 1865a: 510 ; Agrion delicatum Brauer, 1858 ; Ischnura orientalis Selys-Longchamps, 1876 ; Ischnura delicata Selys-Longchamps, 1876 ; Ischnura bhimtalensis Sahni, 1965 .

Distribution ( Fig. 18 ). This species is widespread in the tropical and temperate zones. Dumont (2013) provided molecular evidence that established its current range to lie mainly between Wallace’s Line and the Society Islands ( French Polynesia) in the east ( Paulian 1998), including Australia and Tasmania ( Theischinger & Hawking 2006) and New Zealand ( Rowe 1987). On Grande Terre I. aurora has been recorded from 13 sites where it is rarely abundant. Bigot (1985) reports collecting two females in Nakutakoin (Dumbéa municipality), where we also found it in February 2011.

Habitat. Ischnura aurora is observed in sunlit areas with standing to very slowly running water, not very deep and with dense aquatic vegetation. These habitats can be swamps, pools and ponds but also wetlands along drains and other waterways. The species avoids ultramafic soils.

Biology and behaviour. Ischnura aurora is opportunistic and migratory with a strong dispersion ability. Rowe

(1987) gives some information on immature stages. Eggs measure from 0.75 to 0.78 mm long. In New Zealand, eggs develop within two or three weeks and larvae in seven to eight weeks. Emergence occurs at midday, 2–3 cm above the water, larvae clasping herbaceous plants. Adults fly over calm water with dense aquatic plants reaching the sur- face. Males guard a tiny territory and pursuit females that cross their territories. The mating wheel lasts almost an hour. The female lays its eggs in floating plants or in aquatic plants reaching the surface, but avoids immersion.

Status. Considering its global distribution, I. aurora is not threatened. However, in New Caledonia only small and scattered populations are recorded, so we consider it to be VU.

Figures

FIGURE 17. Ischnura aurora: a) male, b) female.

FIGURE 18. Records of Ischnura aurora.