Monomorium subopacum

Monomorium subopacum (Smith, 1858) (Figure 30) Myrmica subopaca Smith, 1858, p. 127 (w.q.) Portugal (Madeira I.). Palaearctic. Diagnosis Worker. This species can be recognised by the following characters: colour brown, varying in shade but usually gaster darker than head and mesosoma; eyes with 9–11 ommatidia in longest row; mesosoma in profile with metanotal groove feebly impressed; cephalic dorsum without standing setae behind level of frontal; mesosoma without standing setae; petiole and postpetiole each with a single pair of setae; first gastral tergite with an apical transverse row of setae; cephalic surface reticulate-granulate to shagreenate-punctulate. Material examined Four sites: 2; 9; 15; 31. Geographic range. Species widely distributed in North Africa, the Mediterranean Basin, and the Afrotropical, Malagasy, and Oriental regions (Bolton 1987). On the Arabian Peninsula, the species was recorded from the KSA (Collingwood 1985; Sharaf et al. 2023), Oman (Collingwood and Agosti 1996; Sharaf et al. 2018b), Yemen (Collingwood and Agosti 1996), the UAE (Collingwood et al. 2011), and Qatar (Sharaf et al. 2020a). Ecology and biology. Little is known about the ecology and biology of the species, but it was reported from a highly degraded site on the Canary Island at 850 m (Espadaler 2007), whereas in Oman it was found foraging next to an Acacia tree in a dry valley (Sharaf et al. 2018b). The species was described as halophilic in the Sahara (Barech et al. 2017), but it was not collected from saline habitats on the Arabian Peninsula.