Technomyrmex kraepelini

A relatively well collected species for this genus, it occurs in a range of forest habitats and is apparently fairly tolerant of disturbance. Most collections have been made from litter samples but there are also records from baits and sweeping samples. Heterick & Kitching (2022) collected this species in the canopy of a lowland dipterocarp forest in Brunei.

Identification
Bolton (2007) - A member of the Technomyrmex bicolor group. T. kraepelini is closely related to Technomyrmex sundaicus and Technomyrmex rector, the three of which are, within the Technomyrmex bicolor group, mainly darkly coloured, have relatively short scapes and a relatively shorter, broader, mesosoma. T. sundaicus is distinguished from kraepelini by its uniform drab brown colour, which includes all leg segments except for the trochanters and the middle and hind tarsi, which are dull yellow. The middle and hind coxae of sundaicus are the same colour as the mesosoma, whereas in krapelini the coxae are much lighter and contrast strongly with the mesosoma. T. rector, currently known only from a single worker from southern India, appears to have fewer gastral setae than kraepelini and has yellow middle and hind tibiae that are the same colour as the tarsi. The clypeal notch of rector is broader and more shallow than in kraepelini. Other relatives with darkly coloured heads and bodies, Technomyrmex obscurior and Technomyrmex antennus, generally have longer scapes and a narrower, more elongate mesosoma, that only overlap kraepelini at the lowest end of their scale: in obscurior and antennus SI is 122 – 143 and DTI is 156 - 168.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Borneo, Brunei Darussalam, Guam, Indonesia, Malaysia, Marshall Islands, Micronesia (Federated States of), Palau, Philippines, Singapore. Oriental Region: Laos, Thailand.

Nomenclature

 *  kraepelini. Technomyrmex kraepelini Forel, 1905c: 23 (w.) INDONESIA (Java). See also: Bolton, 2007a: 88.

Worker
Bolton (2007) - TL 2.5 - 3.7, HL 0.67 - 1.04, HW 0.59 - 1.02, SL 0.68 - 0.92, PW 0.41 0.57, WL 0.88 - 1.10 (15 measured). Indices: CI 87 - 98, SI 90 - 125, OI 23 - 28, EPI 64 -73, OTI 132 - 157.

Head behind clypeus, dorsum of mesosoma, declivity of propodeum and first gastral tergite all entirely lack setae. Gastral tergites 2 - 4 with long stout setae present that are longer than the maximum diameter of the eye: second gastral tergite with 2 - 3 pairs, third and fourth tergites each with 3 - 4 pairs. Anterior clypeal margin with a distinct median notch the margins of which meet the lateral portions of the anterior margin through rounded curves, not sharp angles. Posterior margin of head concave medially, the extent of the indentation becomes more pronounced In larger workers and in full-face view the head becomes distinctly more cordate with increased size. With head in full-face view the outer margins of the eyes fail to touch the outline of the sides of the head; the latter convex, more stronger so in larger workers. Scape index 125 or less. Clypeal sculpture fine between posterior margin of notch and clypeal suture. In dorsal view the metathoracic spiracles close to, or even abutting, the metanotal groove; distance separating them usually less than one spiracle diameter. Mesosoma with DTI 132 - 157. In profile the straight-line length of the propodeal dorsum at most equal to the depth of the declivity to the spiracle and usually somewhat less; dorsal outline of propodeum usually weakly convex, without a conspicuous notch or indentation at about its midlength. In profile the head, mesosoma, petiole and gaster all the same shade of dark brown to blackish brown, or very nearly so. Anterior coxa brown; middle and hind coxae off-white to yellow and strongly contrasting with the mesosoma and femora. All trochanters yellow. Femora and tibiae brown, same colour as the mesosoma or slightly lighter; often the extreme apex of each segment lighter. Tarsi off-white to yellow, lighter than the femora and tibiae.

Type Material
Bolton (2007) - Syntype workers, Indonesia: Java, Tjompea, leg. 11.iii.1904, ded. 8.vi.1904 (K. Kraepelin) [examined].

References based on Global Ant Biodiversity Informatics

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