Synthemis miranda Selys-Longchamps, 1871

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 : 66-68

Synthemis miranda Selys-Longchamps, 1871

( Fig. 68 )

Synthemis miranda Selys-Longchamps, 1871: 557 .

Distribution ( Fig. 69 ). Endemic to Grande Terre. This large species (wing span up to 90 mm) is recorded from at least 35 localities around the island. Bigot (1985) collected a female in the Baie du Prony. One specimen collected in January 1957 in the Thy Forest is held in the ONNC collection and another, collected in March 1998 in La Foa (Pocquereux valley), is held in the CXMNC collection.

Habitat. Synthemis miranda occurs on mountain forest creeks and streams. It can also sometimes be found in the lowlands. This species tolerates ultramafic soils.

Biology and behaviour. Synthemis miranda is highly territorial, males patrol around shallow ponds (4–5 m 2) or puddles near very fast-flowing creeks. However, oviposition sites are located in pools that are more or less disconnected from the creek. Males are highly aggressive towards other males. Resident males attack other males or any specimen belonging to smaller species that enter their territory. If a female enters a male’s territory, the male will capture her immediately. After tandem formation mating lasts for about 40 seconds in flight 0.6–1.5 m above the ground, while the couple complete six to eight chaotic circling flights over the oviposition site (more than 10 observations). Once released, the female will only lay in the area previously patrolled by the male. She lays eggs onto a substrate with plant debris covered with a film of water (up to a few mm). The exuviae of S. miranda are sometimes found more than 3 m away from the water, clinging to tree trunks, up to 2.5 m above the ground. The larva was described by Lieftinck (1976). On the 22 th January 2010, DG discovered, along the Sanatorium stream (Païta), a pair of S. miranda in the wheel position; the female in this case had extensive wing coloration. Under the still conditions, this couple hung under a twig at more than 5 m height and was observed for more than 10 minutes. It is possible, if not probable, that this species may have two methods of mating, as the Afro-European Libellulidae Crocothemis erythraea (Brullé, 1832) that normally mates in flight for about ten seconds, but may perch to form a wheel depending on the strength of wind and the presence of congeners.

Morphological variations. There is variation in the wing colour pattern in females. Typical females have a strong transparent saffron tint that covers the wing from the basis to the discoidal cell. However, in some females, the tint ranges from deep yellow to light brown and may reach the nodus. Based on sympatric occurrence from the northeast of Grande Terre, Marinov & Richards (2013) formally recognised two forms – f. typica which includes the holotype female and f. extenuata for the females with reduced colour on the wings. These names were proposed for convenience in recording future observations and do not reflect the actual abundance, nor do they have formal nomenclatorial status recognised by the ICZN. A flight of twenty individuals was observed in a creek near the Mont Koghis auberge. At least five or six females had strongly coloured wings, hovering quietly at a height of 4– 10 m.

Status. Synthemis miranda is widely distributed over Grande Terre with large populations. We rank this species as LC.

Figures

FIGURE 68. Synthemis miranda: a) male, b) female f. typica, c) female f. extenuata.

FIGURE 69. Records of Synthemis miranda.