Nesomyrmex denticulatus (Mayr, 1901)

Figs 10B, 11 C–D, 12A, 15

Leptothorax denticulatus Mayr, 1901: 5 (w.q.), South Africa.

Leptothorax (Goniothorax) denticulatus – W.M. Wheeler 1922: 891.

Nesomyrmex denticulatus – Bolton 2003: 272 (see also Bolton 1982: 328; Mbanyana & Robertson 2008: 38).

Diagnosis

The following character combination separates N. denticulatus from the remainder of the group: eyes with 10–12 ommatidia in longest row; in profile mesosomal dorsum with conspicuously impressed metanotal groove; in dorsal view petiolar node laterally denticulate; subpetiolar process with a conspicuous tooth anteriorly followed by a long cuticular flange which runs back to the postpetiolar junction; dorsum of propodeum with standing hairs; first gastral tergite with standing hairs evenly distributed throughout.

Diagnostic comments

The three species, N. denticulatus, N. innocens and N. stramineus, are morphologically very similar and can be well separated from the other species by the laterally denticulate petiolar node. The separation of these three can be challenging though. Nesomyrmex denticulatus is larger in general body size, has larger eyes with more ommatidia, and a subpetiolar process with a conspicuous tooth anteriorly, followed by a long cuticular flange which runs back to the postpetiolar junction, and slightly denser pilosity.

Biology

This species usually nests in cavities of branches on trees and bushes previously excavated by woodboring beetles, lepidopteran larvae or termites (Mbanyana & Robertson 2008). It is found in a variety

of more arid habitats, such as late succession Fynbos, Succulent Karoo with large bushes, along edges of Southern Afrotemperate Forest, and possibly also Albany Thicket (Mbanyana & Robertson 2008).

Distribution

Nesomyrmex denticulatus is only known from South Africa, where it seems to be relatively common in the Western and Eastern Cape regions.