Tetramorium hasinae

Known only from the type collection, a colony found in rotting wood in a tropical rainforest.

Identification
Yamane and Jaitrong (2011) - This species has a much more regular and dense puncto-reticulation on the dorsa of head, mesosoma and waist than in Tetramorium kheperra and Tetramorium polymorphum, and is distinguished from the latter two by the characteristics given in the key.

Distribution based on Regional Taxon Lists
Oriental Region: Thailand.

Nomenclature

 *  hasinae. Tetramorium hasinae Yamane & Jaitrong, 2011: 65, figs. 3A-F (w.q.) THAILAND.

Worker
The worker caste may be monomorphic.

Holotype. HL 0.53, HW 0.51, CI 96, SL 0.34, SI 67, ML 0.28, ED 0.13, PW 0.39, MSL 0.57, PL 0.27, PH 0.20, DPW 0.18.

Head slightly longer than broad, in full-face view with very feebly convex sides, rounded posterolateral comers and almost straight or feebly concave posterior margin. Disc of dypeus consisting of almost fiat basal half and steep apical half, and in full-face view without an anteromedian indentation; anterior margin of clypeus with a narrow transverse plate-like fringe that is situated below the level of the disk and has weakly convex anterior margin. Frontal lobe weakly developed, slightly elevated laterally; frontal carinae strongly divergent, extending well beyond the level of posterior margin of eye; antennal scrobe distinct, strongly margined dorsally by the frontal carina but ill defined ventrally. Eye moderate in size, composed of ca. 30 ommatidia, narrowed anteriorly, located anterior to the mid-length of head; distance between mandibular base and anterior margin of eye slightly shorter than maximum eye length. Mandible subtriangular, with a protruding apical tooth and a smaller preapical tooth; third tooth slightly smaller than the preapical; remaining portion of masticatory margin with a few denticles. Antenna 12-segmented; scape relatively short, not reaching posterolateral comer of head, slightly broadened in distal two-thirds; second segment as long as broad; third to eighth segments each very short, much broader than long, and shorter than the second; antennal club 3-segmented, longer than the remaining portion of funiculus; apical segment distinctly longer than tenth and eleventh combined. Mesosoma short, robust and slightly longer than head, seen from above distinctly broader anteriorly than posteriorly, with broadly rounded anterolateral comers, without any suture separating pronotum, mesonotum and propodeum from one another; in profile mesosoma with evenly convex dorsal outline. Propodeal spines longer than tenth antennal segment; posterior declivity of propodeum short, concave, separated from dorsum by a weak transverse carina and laterally walled by rather developed propodeal lobes, which are roundly convex posteriad. Petiole with a short peduncle; its node seen from above slightly broader than long or almost as broad as long, seen in profile as high as long and with anterior and posterior slopes steep and almost parallel; postpetiole without peduncle; its node similar to petiolar node in size and shape, but distinctly broader than long seen from above, seen in profile slightly lower, with indistinct anterior and posterior slopes. First gastral tergite slightly longer than broad, strongly convex laterally, occupying 4/5 of the whole dorsum of gaster.

Head dorsally densely puncto-reticulate; sides of head similarly but more coarsely punctate. Antennal scrobe superficially and finely sculptured, often with a distinct median carina and irregular shorter carinae. Mandible striate over the surface. Clypeus reticulate. Pro-mesonotum regularly densely puncto-reticulate; mesopleuron and lateral face of propodeum irregularly sculptured; upper half of propodeal declivity finely striate and mat; lower half smooth and shiny. Nodes of petiole and postpetiole almost entirely puncto-reticulate; dorsum of petiolar peduncle densely micropunctate and mat; lateral face of the peduncle more irregularly sculptured and mat. Gastral tergites smooth and shining. Fore coxa in profile finely striate rather than punctate; femora and tibiae smooth and shiny.

Standing hairs on dorsum of head short, of uniform length, and branched; on the venter of head most of hairs decumbent. Hairs on dorsum of mesosoma longer than those on head, rather uniform in length, and branched (mostly trifid); lateral face of mesosoma with sparse indistinct hairs. Dorsa of petiole and postpetiole, and gastral tergites and sternites with dense trifid standing hairs; peduncle and venter of petiole without standing hairs; venter of postpetiole with a few standing hairs. All legs covered with numerous standing or suberect hairs. Body yellowish brown to brown; antennal scape colored as in head; funiculus slightly darker; club often partly yellow; gaster dark brown. Legs lighter; tibiae often yellow.

Queen
Paratype. HL 0.60, HW 0.60, CI 100, SL 0.38, SI 63, ML 0.34, ED 0.l6, PW 0.54, MSL 0.80, PL 0.34, PH 0.26, DPW 0.25.

Similar to the worker in structure, sculpture and pilosity, with the following conditions that should be noted: eye large, slightly shorter than or as broad as the apical segment of antenna; distance between eye and mandibular base much shorter than eye length; median ocellus larger than lateral ocelli; pro-mesonotal suture distinct; mesothoracic parapteron clearly separated from mesoscutellum by a furrow, but ill defined from mesoscutum; mesoscutum much narrower than parapteron; an episternum clearly divided from katepisternum by a furrow; metanotum very short and indistinct; dorsal face of propodeum longer than in the worker and gently sloping. Median carina of clypeus more distinct than in the worker; median carinae on the dorsum of head starting near the base of clypeus, fused into a single carina before median ocellus and reaching the posterior margin of head; mesonotum extensively rugoso-punctate (not punctoreticulate); metanotum coarsely puncto-reticulate; propodeal dorsum with still coarser puncto-reticulation. Dorsum of head, meso soma, waist and gaster covered with dense trifid hairs as in the worker. Body reddish brown with gaster darker; legs and antenna paler, partly yellowish.

Type Material
Holotype: worker, Papra Station, Khao Nan N.P., Nakhon Si Thamrnarat Prov., S. Thailand, TH07-SKY-44 (Sk. Yamane), deposited in THNHM. Paratypes: four workers and one dealated queen from the same colony to which the holotype belongs, deposited in and.

Etymology
The specific name is dedicated to Ms. Sasitom Hasin of Kasetsart University, who much helped us in collecting the material.