Diabolocatantops axillaris (Thunberg, 1815)

Figs 25, 26

References for Socotra.

Krauss (1902): 4 [as Catantops versicolor]; Burr (1903): 412, 420 [as Oxya vicina]; Krauss (1907): 17, 23, 29, plate II, fig. 6 [as Catantops versicolor]; Popov (in Uvarov and Popov (1957)): 371 [as Catantops axillaris]; Wranik (1998): 171; Wranik (2003): 321, plates 151, 155.

Diagnostic notes.

Diabolocatantops axillaris is a medium-sized grasshopper, uniformly coloured light brown or grey, with dark brown sides of the pronotum and long tegmina. An oblique vertical whitish line on the posterior margin of the metathorax is characteristic. The hind femora are uniformly grey-brown, except for a black knee, two dorsal dark transverse bands and an isolated black marking on the dorsal edge of the median external area (Fig. 25).

Taxonomic notes.

Diabolocatantops Jago, 1984 is a mainly Asian genus, defined by the male genitalia and shape of the cerci (Jago 1984; Rowell and Hemp 2018). D. axillaris is the only species that occurs outside Asia in Africa.

Distribution and occurrence.

It occurs across the dry savannah belt south of the Sahara, in the Arabian Peninsula, Iran and several Indian Ocean islands, including Socotra, where it is widespread and ubiquitous at low elevations (Fig. 26). It is one of the most common insects on the island (Popov in Uvarov and Popov (1957)). In 2009 and 2010, we encountered hundreds of individuals on many lowland sites.

Habitat and biology.

D. axillaris is found in various habitats on Socotra, but always occurs in the direct vicinity of vegetation. The species is numerous at low elevations, less so higher up in the Hagher. Records are from year-round, from 0–800 m a. s. l. Specimens overnight in shrubs like Senna socotrana . Records are from sparse dwarf and low Croton - Jatropha shrubland and submontane grassland, less from higher shrubland, woodland and forest.