Tetramorium exile

Known only from the type locality. Nothing is known about the biology of .

Identification
Csösz, Radchenko and Schulz (2007) - According to the literature (Collingwood 1961a, 1961b, Pisarski 1967a, 1967b, 1969) and collection materials there are no similar Tetramorium species, described from Afghanistan. Workers of T. exile differ from related species by absence of psammophore, relatively small eyes, extremely narrow frons, the very long and smooth scape, and by the trapezoidal petiolar node. Tetramorium exile is mostly similar to Tetramorium anatolicum and Tetramorium chefketi, but differs from the latter by the shape of petiolar node: in T. exile it is relatively high and short, trapezoidal in profile, while in T. chefketi it is relatively low and longer, cubic in profile. The following Discriminant D(3a) function proves the separation between T. exile and T. chefketi: D(3a) = 0.052 PPW -0.057 FL -0.081 NOL +14.667, T. exile D(3a) = +3.418 ±0.901 [+2.169, +4.756] (n=33), T. exile, holotype D(3a) = +3.023, p< 0.001, T. anatolicum D(3a) = +3.164 ±0.796 [+1.746, +4.606] (n=38), T. anatolicum, holotype D(3a) = +3.246, p< 0.001, T. chefketi D(3a) = -3.417 ±1.004 [-5.680, -0.524] (n=107), T. chefketi lectotype D(3a) = -4.179, p< 0.001; T. sarkissiani lectotype D(3a) = -2.809, p< 0.001; T. turcomanicum syntype worker D(3a) = -4.169, p< 0.001.

T. exile differs from T. anatolicum by its longer scape and narrower frons. The following Discriminant D(2a) function provides the separation between T. exile and T. anatolicum: D(2a) = 0.081 SL - 0.151 FL - 7.652.

T. exile D(2a) = +2.683 ±0.762 [+1.193, +3.493] (n=33), T. exile, holotype D(2a) = +3.493, p< 0.001, T. anatolicum D(2a) = -2.683 ±1.064 [-4.682, -0.042] (n=38), T. anatolicum, holotype D(2a) = -3.117, p< 0.001.

Distribution based on Regional Taxon Lists
Palaearctic Region: Afghanistan.

Castes
Known only from the worker caste.

Nomenclature

 *  exile. Tetramorium exile Csösz & Radchenko, in Csösz, Radchenko & Schulz, 2007: 22, figs. 39-42 (w.) AFGHANISTAN.

Worker
Figs 39–42. Holotype: CL: 725; CW: 675; FR: 240; FL: 240; SL: 585; ML: 790; MW: 440; PEW: 215; PEH: 240; NOH: 130; NOL: 130; PEL : 155; PPW: 240; PPL: 160; PPH: 210; SPL: 90; SPSP: 130; EL: 135; EH: 100; ED: 170; Small size, CS 695 [620, 743].

Whole body and appendages brown to dark brown. Head elongated, CL/CW 1.06 [1.04, 1.08], with very feebly convex sides, straight occipital margin and narrowly rounded occipital corners. Eyes small, EYE 0.167 [0.158, 0.175]. Frons very narrow, FR/CS 0.34 [0.33, 0.35], frontal lobes as wide as frons, FL/FR 1.0 [1.0, 1.02]. Scape very long, SL/CS 0.84 [0.82, 0.85], without longitudinal dorsal carina basally, smooth and shiny. Promesonotal dorsum slightly convex, metanotal groove very shallow or completely absent. Propodeal teeth moderately long and acute, directed mainly upwards. Petiolar node trapezoidal in profile, NOH/NOL 1.04 [0.90, 1.16], petiole relatively high, PEH/NOL 1.83 [1.70, 1.96]. General appearance moderately rugose, ground surface microreticulate, dull. Head dorsum longitudinally rugose, ground surface microreticulate, occiput rugoso-reticulate. Alitrunk dorsum and petiolar node rugoso-reticulate ground surface microreticulate, mesopleuron usually rugulose and microreticulate, dorsum of postpetiole longitudinally rugulose and microreticulate. Polygonal striation continuous on 1st gastral tergite (see fig. 8.). Ventral surface of head with several short and few moderately long, straight setae arising posterior to buccal cavity (see fig. 5.).

Type Material
HOLOTYPE /: AFGHANISTAN – O-Afghanistan, Walang, 2520m, Salangtal, Hindukusch, 29.09.1952. leg. J. Klapperich ; PARATYPES: 35 workers from the same nest (3 workers: HNHM, 4 workers:, 25 workers: NHMW 1 worker: PCAS).

Etymology
This adjective [exilis: -e; exile (neutrum) = slender] refers to the elongate body of this species.

References based on Global Ant Biodiversity Informatics

 * Csősz S., A. Radchenko, and A. Schulz. 2007. Taxonomic revision of the Palaearctic Tetramorium chefketi species complex (Hymenoptera: Formicidae). Zootaxa 1405: 1-38.