Genus Ascalaphus Fabricius, 1775
Ascalaphus Fabricius, 1775: 313 . Type species: Myrmeleon barbarum Linnaeus, 1767: 914 . Monotypy.
Helicomitus McLachlan, 1873a: 261 . Type species: Ascalaphus insimulans Walker, 1853: 429 . Subsequent designated by McLachlan, 1873b: 402.
Diagnosis. Ascalaphus can be characterized by the combination of the following characters: wing membrane hyaline, without markings (Figs 4A–C, 5A–C); pterostigma dark brown to light brownish, usually wider than long, rhomboid-shaped; apical area beyond Sc+R with two rows of cells; forewing without triangular projection on the anal area. Moreover, the proximal 1/3 of flagellomeres in male with distinctly S-shaped (Fig. 6D), but straight in female (Fig. 6E); the mesoscutum anteromedially with a brownish triangular process (more prominent in male but smaller in female) (Figs 6A–B); the abdominal terga 4–6 with or without dense, long black setae in male (Figs 4A–C), absent in female (Figs 5A–C).
Note. To date, eight species of the genus Ascalaphus have been recorded from Asia and Pacific Islands (Sziráki 1998). Two of them, i.e., A. abdominalis (Kimmins, 1949) and A. dicax Walker, 1853 from Pakistan, were listed as present in the National Museums of Scotland by Whittington (2002), but without precise location data. However, Ascalaphus abdominalis and A. dicax are widely distributed in India (Fig. 27). Despite no precise location, it is possible to infer that it was collected in the Punjab province because of the distribution data of these species from the neighbouring countries, i.e., India and Iran. No new specimens were recorded in this study. The finding of A. prothoracicus (Kimmins, 1949) is a new record for Pakistan; the species was originally described from India by Kimmins (1949) and placed in the genus Helicomitus . Tjeder later (1972) considered Helicomitus as synonym of Ascalaphus (Oswald & Penny 1991) . Prior to this study A. prothoracicus was known only from India and Thailand (Ghosh 1988; Michel 2005).
Key to Ascalaphus species from Pakistan
1. Mesonotum anteromedially with a distinct brownish triangular process in male (Fig. 6A), relatively smaller in female (Fig. 6B)........................................................................... A. prothoracicus (Kimmins)
_. Mesonotum without any process (Kimminis, 1949: figs 1A, E [A = dixcax; E = abdominalis])........................ .. 2
2. Tergum 4 with a median dilation in lateral view, densely covered with short black setae (Kimmins, 1949: fig. 3)......................................................................................... A. abdominalis (Kimmins)
_. Tergum 4 without dilation, covered with short black setae.......................................... A. dicax Walker