Synthemis ariadne Lieftinck, 1975

(Fig. 60)

Synthemis ariadne Lieftinck, 1975: 160 .

Distribution (Fig. 61). Endemic to Grande Terre. This species is known from six localities spread along the central range. Winstanley (1984c) collected the first female in November–December 1981. Its apparent rarity is probably due to its early flight period, from mid-October to late December, a time of the year collectors seldom search for Odonata .

Habitat. Synthemis ariadne frequents mountain creeks and streams, covered by forests, on non-ultramafic soil.

FIGURE 62. Synthemis campioni: a) male, b) female.

Biology and behaviour. The biology of this species is little known. Its final stadium larvae, described by supposition (Winstanley 1984b; Fleck 2005), lives in small creeks and their tributaries. Hiding among rocks, it may occasionally be found with S. fenella Campion, 1921 . Emergence occurs not far above water surface (Winstanley 1984b). Fleck (2005) reared several larval stages in laboratory conditions without obtaining any adults because its development was so slow. This author concluded that the larval development takes at least four years.

Status. Synthemis ariadne is known from a very few localities scattered over the main island. Although its habitat is not immediately threatened, we rank it EN, because of its rarity.