Libelloides macaronius (Scopoli, 1763)

(Figs. 2E, 13)

Brauer (1854, 1855) deeply treated the larval morphology and life history of this species, representing the first accurate account regarding an ascalaphid larva. Later descriptions of the larva were realized by Hagen (1873) and Pieper and Willmann (1980). A photo of a larva is shown in U. Aspöck & H. Aspöck (1999).

Examined specimens. Italy. Friuli Venezia Giulia, 3 L3 laboratory-reared from a female collected at Trieste (TS), VI.2010 (L. Morin) .

Description of 3 rd instar larva. Size (based on 3 specimens): BL 11.81 mm; HL 2.43 mm (2.38–2.49), HW 2.81 mm (2.77–2.86), ML 2.77 mm (2.63–2.90), HW/HL 1.15, ML/HL 1.14. General colouring pale brown with dark areas and markings, dorsal side with a median paler stripe, ventral side pale mottled with dark grey; head capsule dark brown, anterior portion darker, ventral side of the head dark brown, mandibles dark brown; legs with dark brown coxae and lighter femora, tibiae and tarsi. Head wider than long, slightly dilated posteriorly; mandible longer than the head capsule (Fig. 13a) interdental mandibular pseudo-teeth (4–5)(3–4)(0–1) (Fig. 13b); external margin of the mandible covered by short setae. Pronotum brown with darker stripes and covered with short setae; mesothoracic spiracles brownish with black apex. Abdominal spiracles dark brown; VIII sternite with brown spots on the odontoid processes; IX sternite with longitudinal brown markings and a dark apex (Fig 2E).

Bio-ecology. L. macaronius is a widespread, euryoecious species occurring in open habitats with herbaceous vegetation from the sea level to the mountains. This ascalaphid is a typical species of steppes and similar biotopes, explaining its wide distribution in Central Asia. The larvae live on the soil in the same environments inhabited by the adults.

Distribution. Widely distributed in central and eastern Europe and Asia, from easternmost part of northern Italy (surroundings of Trieste) eastward to western China.

Remarks. The larva of L. macaronius disposes on average of a greater number of pseudo-teeth (3–4) between the basal and median mandibular teeth than congeners.