Strumigenys lewisi

Japanese Name

Uroko-ari

Cameron, P. (1886) On a new species of Strumigenys (S. lewisi) from Japan. Proceedings of the Manchester Literary and Philosophical Society 25: 229-232.

Strumigenys godeffroyi var. lewisi Mayr (Mayr, 1887) , Strumigenys lewisi Brown (Brown, 1949) ,

Total length of workers around 2 mm. Body color yellow to brown. Outer margin of mandibles feebly convex in full-face view; apical fork with 2 or 3 small intercalary denticles. A subapical tooth present on each mandibular shaft, each as long as the space between the mandibular shafts. Standing hairs on mesosoma not abundant, numbering only 4 to 8. Dorsal outline of mesosoma only weakly interrupted by metanotal groove, which is shallow. Spongiform lamella developed below propodeal spine. Most parts of mesothorax and propodeum unsculptured, smooth and shining.

Very similar to Strumigenys sp. 4 and Strumigenys sp. 9. It can be difficult to separate the workers, but S. lewisi is marked by its females, which have the mesonotum relatively low, and have relatively small posterior ocelli and eyes. Nests are found under stones or logs, in the soil, decayed stumps or bamboo stems. Winged forms appear in August. Details of predatory behavior were reported by Masuko (1984, 1985). The workers prey on Collembola (Okamoto, 1953, Masuko, 1984). Colonies are small, usually with between tens and 100 workers (Teranishi, 1929). The species is polygynous. It is one of the most common soil-inhabiting ants of Japan. Most former records of "S. lewisi" probably involved Strumigenys species 4 or Strumigenys species 9 of this account, and thus need reassessment.

Honshu, Shikoku, Kyushu, Tsushima I., Yaku I.; Mainland China, Korean Peninsula, Hawaii, India, Sri Lanka, Myanmar.