Tetramorium chefketi

At Rawdhat Khorim, Saudia Arabia, this species is relatively common and observed foraging on Ziziphus nummularia (Burm. f) Wight & Arn. (Rhamnaceae). The species has two abundance peaks, in June and November. It was collected using pitfall traps and beating vegetation (Sharaf et al., 2013). Pashaei Rad et al. (2018) found this species in Iran in Caspian moist littoral and moderate rainfall montane areas.

Identification
Csösz, Radchenko and Schulz (2007) - Workers of T. chefketi can be separated from related species by the lack of psammophore, relatively small eyes, long and smooth scape without dorsal carina basally, coarse body sculpture and cubic petiolar node. Workers of T. chefketi mostly resemble those of Tetramorium rhodium and Tetramorium sanetrai, but SL/CS gives appropriate discrimination between them. Discriminant D(3a) function between workers of T. chefketi vs. Tetramorium exile and T. chefketi vs. Tetramorium anatolicum proves the separation (see differential diagnosis of T. exile).

Gynes of T. chefketi can be distinguished by lacking of psammophore, long and smooth scape, wide scutum, relatively narrow petiole and postpetiole, and rugoso-reticulate katepisternum. Gynes of T. chefketi mostly resemble those of T. sanetrai, but SL/CS gives appropriate discrimination between them.

Distribution
This species was recorded from Saudi Arabia (Collingwood, 1985), Oman and Yemen (Collingwood and Agosti, 1996). Outside Arabia, it has been reported from several parts of the Palaearctic region including southern Europe (Greece, Bulgaria, Macedonia, Romania), southern Ukraine, south of western Russia, northwestern Caucasus, Turkey, Turkmenistan, northern Kazakhstan, southeastern Siberia, to the east to Kyrgyzstan and Altai Mountains (Csõsz et al., 2007) (Sharaf et al., 2013).

Distribution based on Regional Taxon Lists
Afrotropical Region: Saudi Arabia. Palaearctic Region: Armenia, Bulgaria, China, Georgia, Greece, Iran, Kyrgyzstan, Republic of Macedonia, Russian Federation, Turkey, Ukraine.

Nomenclature

 *  chefketi. Tetramorium caespitum var. chefketi Forel, 1911d: 332 (w.) TURKEY. Raised to species: Agosti & Collingwood, 1987a: 56. Senior synonym of taurocaucasicum: Güsten, Schulz & Sanetra, 2006: 16; of sarkissiani, turcomanicum: Csösz, Radchenko & Schulz, 2007: 18.
 * sarkissiani. Tetramorium caespitum var. sarkissiani Forel, 1911d: 332 (w.) TURKEY. Subspecies of ferox: Menozzi, 1934: 163. Junior synonym of chefketi: Csösz, Radchenko & Schulz, 2007: 18.
 * turcomanicum. Tetramorium caespitum st. turcomanicum Santschi, 1921a: 111 (w.q.) KAZAKHSTAN. [First available use of Tetramorium caespitum subsp. caespitum var. turcomanica Emery, 1909d: 702; unavailable name.] Raised to species: Tarbinsky, 1976: 109. Junior synonym of chefketi: Csösz, Radchenko & Schulz, 2007: 18.
 * taurocaucasicum. Tetramorium taurocaucasicum Arnol'di, 1968: 1813, fig. 12 (w.q.m.) UKRAINE. Junior synonym of forte: Radchenko, 1992b: 51; Atanassov & Dlussky, 1992: 152; of chefketi: Güsten, Schulz & Sanetra, 2006: 16.

Worker
Csösz, Radchenko and Schulz (2007) - Lectotype. CL: 990; CW: 990; FR: 370; FL: 385; SL: 810; ML: 1150; MW: 660; PEW: 360; PEH: 365; NOH: 220; NOL: 230; PEL: 225; PPW: 415; PPL: 230; PPH: 355; SPL: 135; SPSP: 230.

Figss 35–38. Medium to large size, CS 869 [740, 972]. Whole body and appendages dark brown to black. Head nearly square, CL/CW 1.01 [0.97, 1.04], with very feebly convex sides, straight occipital margin and rounded occipital corners. Eyes small, EYE 0.171 [0.165, 0.184]. Frons moderately narrow, FR/CS 0.37 [0.35, 0.39], frontal lobes usually wider, FL/FR 1.03 [1.0, 1.09]. Scape long, SL/CS 0.82 [0.78, 0.87], without longitudinal dorsal carina basally, smooth and shiny. Promesonotal dorsum slightly convex, metanotal groove rather deep. Propodeal teeth long. Petiolar node cubic in profile, NOH/NOL 0.86 [0.76, 0.97], petiole relatively low and long, and PEH/NOL 1.52 [1.37, 1.69]. General appearance coarsely rugose, ground surface microreticulate. Head dorsum longitudinally rugose and microreticulate, occiput and sides rugoso-reticulate, ground surface microreticulate. Alitrunk dorsum, mesopleuron and dorsum of petiolar node rugoso-reticulate, ground surface coarsely 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 longer straight setae, arising posterior to buccal cavity (see fig. 5.).

Queen
Csösz, Radchenko and Schulz (2007) - Figs 32–34. Large size, CS 1121 [1060, 1180]. Whole body and appendages black. Head wider than long, CL/CW 0.92 [0.89, 0.95] with sides and occipital margin straight, and widely rounded occipital corners. Frons moderately narrow, FR/CS 0.38 [0.36, 0.40], frontal lobes as wide as frons, or slightly wider FL/FR 1.01 [1.0, 1.03]. Scape long, SL/CS 0.77, without longitudinal dorsal carina basally, smooth and shiny. Head wider than scutum, MW/CS 0.94 [0.88, 1.01]. Propodeal teeth long. Dorsal crest of petiolar node straight in frontal view; in profile, node with flattened dorsal surface. Petiole and postpetiole relatively narrow, WAIST 0.90 [0.86, 0.96]. General appearance coarsely rugose, ground surface microreticulate, dull. Head dorsum, occiput and sides rugoso-reticulate, ground surface microreticulate. Frons longitudinally rugose and microreticulate. Scutum and scutellum longitudinally rugose, scutellum more or less smooth medially. Sides of alitrunk, rugoso-reticulate and microreticulate, ventral part of katepisternum always rugulose, or microreticulate. Dorsum of petiolar node and postpetiole coarsely reticulate and microreticulate. Polygonal striation disrupted on 1st gastral tergite, superficially microreticulate basally. Ventral surface of head with several short and few longer straight, or few C-shaped setae arising posterior to buccal cavity.

Male
Csösz, Radchenko and Schulz (2007) - Whole body and appendages black. Head with convex sides, rounded occipital margin and widely rounded occipital corners. Head as wide as scutum. Propodeal teeth short, propodeum angulate in profile. Dorsal crest of petiolar node in frontal view with sharp, slightly emarginate, transversal edge. Head, alitrunk and waist coarsely sculptured, ground surface microreticulate, dull. Head rugoso-reticulate, ground surface microreticulate. Scutum and scutellum longitudinally rugose. Sides of alitrunk longitudinally rugose. Dorsum of petiolar node and postpetiole coarsely reticulate. Polygonal striation disrupted on 1st gastral tergite.

Type Material
Csösz, Radchenko and Schulz (2007) - Lectotype worker and paralectotype workers. Lectotype designation. We investigated three syntype workers mounted on one pin, labeled as: “T. caespitum L.”, “Bou Youk Déré”, “Bosphore européen (Forel)”, “v. chefketi Type For”, “v. T. chefketi For”, Typus, Coll. Forel.

The lectotype is positioned on the distal end of the upper card (this is mentioned on the reverse side of lectotype label). The lectotype is in good condition, except that the left funiculus (excluding the first segment), the left foreleg and the tarsus of the right hind leg are missing.