Tetramorium caespitum ( Linnaeus, 1758 )

Sharaf, Mostafa R., Wetterer, James K., Mohamed, AbdulAziz M. A., Georgiadis, Christos, Nasser, Mohamed G. & Aldawood, Abdulrahman S., 2024, Filling gaps in global myrmecology: ants of the Kingdom of Bahrain (Hymenoptera: Formicidae), Journal of Natural History 58 (41 - 44), pp. 1705-1786 : 1760-1763

Tetramorium caespitum ( Linnaeus, 1758)

( Figure 36 )

Formica caespitum Linnaeus, 1758, p. 581 (w.) Sweden. Palaearctic.

Diagnosis

Worker. TL 2.5–4 mm; uniform black-brown to black; head with parallel sides and straight posterior margin in full-face view; eyes of medium size with about 7 ommatidia on longest row, located at midline of head in full-face view; anterior clypeal margin without anterior emargination; propodeal spines short, broadly denticulate, and upward directed; head and mesosoma regularly longitudinally striate; metanotal groove distinctly impressed; dorsum of petiolar node smooth or with feebly microreticulate; gaster smooth and shining.

Material examined

One site: B.

Geographic range. A Holarctic species geographically distributed from the USA to Japan, North Africa to all of Europe ( Collingwood 1979; Wagner et al. 2017), and presumably native to the Palaearctic ( Seifert 1996) or the Oriental ( Smith 1965) regions. On the Arabian Peninsula it was recorded from the KSA ( Aldawood and Sharaf 2009).

Ecology and biology. The nesting habits of T. caespitum range from natural to urban environments ( Collingwood 1979; Seifert 2007). The natural habitats include the open borders of woodlands, meadows, pastures, heaths, arid or semi-arid grasslands, vineyards, fallow grounds, ruderal areas, road embankments, rock heaps, gravel pits, and riverbanks, while the urban territories include public parks, pavements, and roadsides ( Klotz et al. 2008). Nests are constructed directly in the earth, under stones, or in rotten or dead wood ( Smith 1965; Collingwood 1979) and there is frequently a single queen (monogyny) with thousands of workers ( Seifert 1996), or polygyny ( Martinez 1993). The species is a generalised seed harvester and an active predator on arthropods, and attends aphids for honeydew ( Smith 1965; Wagner et al. 2017). A nest series at the Asir Mountains ( KSA) was found in leaf litter and among grasses of the family Gramineae and coexisting with a single worker of Oxyopomyrmex nitidior Santschi, 1910 ( Aldawood and Sharaf 2009).

Figures

Figure 36. Tetramorium caespitum. Neotype worker. (A) Body in profile. (B) Head in full-face view, CASENT0919632, AntWeb.org (Flavia Esteves). (C) Distribution map.