Acheta rufopictus Uvarov, 1957

Figs 134, 135, 136, 137, 138

References for Socotra.

Burr 1903: 412, 422 [as Gryllus lepidus]; Uvarov (in Uvarov and Popov (1957)): 365–366; Chopard 1961: 271, plate IV; Gorochov 1993: 86; Wranik 2003: 316, plates 147, 149; Chintauan-Marquier et al. 2016: 57, 71; Massa et al. 2022: 10, 11, 16, 24.

Diagnostic notes.

Acheta rufopictus is a medium-sized cricket with a relatively uniform dark body. Its head is dark reddish-brown to black, with only the median and lateral ocelli light and a light spot behind the eye (Figs 134, 135). The pronotum is uniformly blackish-brown on the disc, sometimes with a reddish hue and has a light hind margin and lateral lobes with a broadly yellowish margin. The tegmina have four harp veins. Legs are pale. Nymphs are strikingly patterned (Fig. 138).

Distribution and occurrence.

Endemic to Socotra. The crickets are found throughout the island. In 2009 and 2010, the species was common in Ayhaft, Qeysoh, Adho Dimello, Begobig and various localities in Dixam (Fig. 136).

Habitat and biology.

Found in almost all habitats, ranging from sandy plains, limestone plateaus and urbanisation to montane shrub- and woodlands in the Hagher, from 0–1470 m a. s. l. Nocturnal and hiding by day in all kinds of crevices. Adults are present year-round.

Bioacoustics.

The calling song of Acheta rufopictus is a simple syllable, more or less regularly repeated at a maximum rate of about 2.5 per second (Fig. 137; https://www.xeno-canto.org/877940). Syllable duration is about 35 ms. Only the closing hemisyllable produces sound. The carrier frequency of the song is around 5.4 kHz. The song has some harmonics at higher frequencies.

Remarks.

Chintauan-Marquier et al. (2016) genetically analysed a male specimen from Ayhaft (26 Oct 2010). Sequences are stored in GenBank (KR 904150.1; KR 903964.1; KR 903786.1; KR 903623.1; KR 903446.1; KR 903272.1; KR 903101.1).