Tetramorium ferox Ruzsky, 1903

Csősz, Sándor & Schulz, Andreas, 2010, A taxonomic review of the Palaearctic Tetramorium ferox species-complex (Hymenoptera, Formicidae), Zootaxa 2401, pp. 1-29 : 20-23

Tetramorium ferox Ruzsky, 1903

Tetramorium caespitum var. ferox Ruzsky, 1903: 309 . Syntype workers, gynes, male (2w, 2q, 1m): Russia, Saratov (Ruzsky) [labels: Tetr. caespitum L., v. ferox Rusz, Ssaratov M.R. ] (examined) [MSNG, MHNG]. Raised to species by Cori & Finzi, 1931: 239.

Tetramorium confinis Radchenko & Arakelian, 1990: 374 . Holotype gyne and paratype workers, gynes, male: Armenian Republic, Talyn 14.VI.1989 (Kalashyan); Ukraine, Crimea, Krasnolesje 28.VI.1978 (E. Malij) [labels: ArmSSR, 1km severneje, g.Talyn, Kalashyan, 14.06.89. Krym Krasnolesje, kosh-kaya, No 83, E. Malij, 28.VI.1978; gn. V shcheli kamnja] (3w, 2q, 1m paratypes examined) [SIZK]. New synonymy.

Tetramorium caespitum st. ferox var. perspicax Santschi, 1921: 111 . Unavailable name.

Tetramorium perspicax Radchenko, 1992b: 56 . Syntype workers, gyne (10w, 1q): Turkey, Ankara (G.D. Kerville) [labels: Asie Min., Angora, (G.d. Kerville); 243; Tetramorium , ferox Ruzs. , v. perspicax Sant., Santschi det. 1920; Sammlung, Dr. F. Santschi, Kairouan] (examined) [NHMB]. First available use of Tetramorium caespitum st. ferox var. perspicax Santschi, 1921: 111 . Junior synonym of feroxoide: Radchenko, 1992b: 56 . New synonymy.

Tetramorium (Lobomyrmex) ferox subsp. silhavyi Kratochvil, 1941: 84. Syntype worker, gyne: Czech Republic, Slovakia and Hungary (not examined). Also described as new by Kratochvil, 1944: 72. Junior synonym of ferox: Bernard, 1967: 235 .

Description of workers (figs 38–40). Medium to large size, CS 825 [693, 918]. Whole body and appendages greyish brown to dark brown. Head slightly longer than broad, CL/CW 1.03 [0.99, 1.09], with feebly convex sides, straight posterior margin with widely rounded corners. Eyes small, EYE 0.16 [0.15, 0.18]. Frons moderately wide, FR/CS 0.39 [0.36, 0.41], frontal lobes usually as wide as the frons, rarely slightly broader, FL/FR 1.01 [1.00, 1.03]. Scape long, SL/CS 0.79 [0.74, 0.83], with a feeble dorsal carina basally, its surface very finely microreticulate. Promesonotal dorsum slightly convex, metanotal groove shallow. Propodeal denticles moderately long. Petiolar node moderately high, NOH/NOL 1.05 [0.88, 1.29] trapezoid to cubic seen in profile.

Head longitudinally rugulose and microreticulate, posterior surface ruguloso-reticulate, ground surface microreticulate, appears dull. Mesosoma dorsum and mesopleura ruguloso-reticulate, ground surface coarsely microreticulate. Dorsum of petiolar node ruguloso-reticulate, ground surface microreticulate, median part smooth. Dorsum of postpetiole rugulose and microreticulate. First gastral tergite smooth, appears shiny. Ventral surface of head with a row of short setae only (without long C-shape hairs).

Description of gynes (figs_35–37, 41). Medium to large size, CS 999 [955, 1095]. Whole body and appendages black. Head broader than long, CL/CW 0.92 [0.90, 0.94] with sides and posterior margin straight, with widely rounded corners. Head trapezoid in full face view, narrower at genae. Frons moderately wide, FR/ CS 0.40 [0.39, 0.42]. Scape long, SL/CS 0.75 [0.70, 0.81], with a feeble dorsal carina basally, its surface smooth and shiny. Head slightly narrower than scutum, MW/CS 1.03 [0.99, 1.08]. Propodeal teeth long. Petiole and postpetiole wide, CS/PEW 1.65 [1.56, 1.78], CS/PPW 1.29 [1.11, 1.43].

Head dorsum, posterior surface and sides ruguloso-reticulate, ground surface microreticulate. Frons longitudinally rugulose and microreticulate. Scutum and scutellum longitudinally rugulose. Sides of mesosoma, rugoso-reticulate and microreticulate, ventral part of katepisternum always rugulose, or microreticulate. Dorsum of petiolar node and postpetiole coarsely reticulate and microreticulate. First gastral tergite smooth, appears shiny. Ventral surface of head with a row of short setae only (without long C-shape hairs).

Description of males. Head sides feebly convex, posterior margin widely rounded. Scutum much broader than head. Propodeal denticles reduced, propodeum nearly rounded in profile. Dorsum of petiolar node blunt, dorsolaterally sharp and angulate. Whole body and appendages black. Head, scutum, scutellum, anepi- and katepisternum as well as petiole and postpetiole finely rugulo-reticulate, between main sculpturation microreticulate. First gastral tergite smooth, appears shiny.

Diagnosis. The feebly rugulose general sculpture, the microreticulate ground surface, and the relatively sparse pubescence on the first gastral tergite make the T. ferox gynes unique within this group.

Tetramorium ferox workers cannot be confused with those of T. diomedeum or T. aegeum . The general appearance of the head and mesosoma of T. ferox workers is always rugulose, microreticulate and dull, but head and mesosoma of the latter two species are always shiny and usually at least partly smooth.

Tetramorium feroxoide workers usually bear much feebler (and often parallel) rugulae on head and mesosoma than T. ferox workers, but in a few cases T. feroxoide workers can be confused with the smallest T. ferox workers. Discriminant function D(3b) = -0.0465 SL +0.0354 PPW +93.9076 EYE +1.5372 for workers of T. ferox and T. feroxoide resulted in 99.4% success, with only one erroneously identified case of the 177 individuals, while 100% of the nest samples were correctly identified. The mean D(3b) scores for T. ferox workers (n=129) was -1.748 ±1.02 [-4.799, +0.277], for nest means (n=22) -1.560 ±0.84 [-3.526, -0.254]. The mean scores for T. feroxoide workers (n=48) was + 1.748 ±0.95 [+0.070, +4.355], for nest mean (n=8) +2,421±0.54 [+3.073, +0.539].

FIGURES 35–41. Tetramorium ferox Ruzsky, 1903 , Gyne mesosoma, petiole and postpetiole, dorsal view (Fig. 35), lateral view (Fig. 36); gyne head, dorsal view (Fig. 37); worker head, dorsal view (Fig. 38); worker mesosoma, petiole and postpetiole, dorsal view (Fig. 39), lateral view (Fig. 40); sparse pubescence pilosity on 1st gastral tergite of a gyne (Fig. 41).

Separation of T. densopilosum and T. ferox workers is very difficult on the basis of traditional characters only, though T. densopilosum workers have slightly trapezoidal heads and the petiolar node slightly angulates anterororsally. Discriminant function D(4b) = 0.0375 CL +0.0781 FR -0.0487 PPW -0.1302 POC +1.2872 for T. ferox and T. densopilosum workers resulted in 99.3% success, with only one erroneously identified case of the 137 individuals, while 100% of the nest the samples were correctly identified. The mean D(4b) scores for T. ferox workers (n=129) was -1.748 ±1.02 [-4.799, +0.277], for nest means (n=22) -1.560 ±0.84 [-3.526, - 0.254]. The mean scores for T. densopilosum workers (n=8) was +1.656 ±0.75 [+0.983, +2.910], for nest mean (n=2) +1.632 ±0.04 [+1.60, +1.663].

For the results of cumulative discriminant analysis for worker caste see Tables 3 & 4 and for gynes see Tables 5 & 6 . Morphometric characters and indices for workers and gynes are provided in Table 7 & 8.

Distribution. Widely distributed over the western Palaearctic, from Central Europe to the Caucasus and Turkey.

Material examined. AUSTRIA—Spitzerberg vic. Prellenkirchen, (16˚57'E/48˚05'N) nr. AUT002 23.06.2002. leg. B. C. Schlick-Steiner & F. M. Steiner (7w / HNHM);

BULGARIA—Dolno Ezerovo ad Burgas 20.07.1957. leg. W. nr. 70/57 (10w / HNHM); Kărdžali 29.05.1956. leg. Bielawski et Goljan (4w / HNHM);

HUNGARY—Pécs 1929.08.28. leg. Szabó-Patay (10w / HNHM); Kalocsa 1936.03.23. leg. Erdős (1w / HNHM); Budapest 1905.04.20. leg. Biró (1w / HNHM); Budapest 1918.05.12. S. h. leg. Szabó-Patay (10w / HNHM);

ROMANIA—Orşova, 27.06.1957. leg. B. Pisarski nr. 68/57 (1w / HNHM); Black Sea Region, S Euforie, 12km S Constanta, 20mh, 04.vii.2005, leg. A. Schulz (12w PCAS);

SLOVAKIA—Stiavnické vrchy Mts., Súdovce, 48°13.7’N, 18°49.5’E 230mH 23.05.2007 leg. Wiezik (5w / HNHM); Medovarce, u Krupiny, Slov.occ. nr. 7779-80, 24.6.1989. leg. P. Werner (1w, 1m, / Central Europe Czechoslovakia Ex. coll. P. Werner); Slov.occ. Medovarce, u Krupiny, Slov.occ. nr. 7779-80 24.6.1989. leg. P. Werner Mess 0 41 (1q / Central Europe Czechoslovakia Ex. coll. P. Werner); Ajnácskő [Hajnáčka] 1909.06.0 9. leg. Szabó (5w, 1m / HNHM);

TURKEY—Adana- 10km E Carmadi Ala Dag Gebirge 1800–2000mH Tannenwald 70% 31.05.1993. leg. Schulz nr. 958 (6w / HNHM); Aksaray- 50km NW Aksaray 10km NW Acipinar 1000 mH Artemisia Steppe, Straßenrand 0 2.06.1993. leg. Schulz nr. 981 (5w / PCAS); Aydos Dagi, 32rkm SE. Halkapinar, Prov. Konya, 1600–1800mH, 0 8.05.1997. leg. A. Schulz, K. Vock, M. Sanetra nr. 229 (6w / PCAS, 3w / HNHM); Aykirikçi, Prov. Kütahya, (39,040N / 30,120E) 1027mH 12.06.2004. leg. A Schulz nr. 196 (2w, 2q, 2m / PCAS, 3w, 6g, 6m / HNHM); Aykirikçi, Prov. Kütahya, (39,040N / 30,120E) 1027mH 12.06.2004. leg. A Schulz nr. 206 (3w / PCAS, 5w, 2m / HNHM); Incesu 2rkm NE., Kayseri 30km SW., Prov. Kayseri, 1100mH 10.05.1997. leg. A. Schulz, K. Vock, M. Sanetra nr. 267 (6w / PCAS, 3w / HNHM); Kars s/Digor 1800m 15.06.1986. leg. Besuchet-Löbl Burckhardt (4w, 1q / PCAS, 1w / HNHM); Kastamonu- 10km S Küre 50km N Kastamonu Straßenrand, 1000mH 21.05.1990. leg. Schulz (3w, / PCAS); Kastamonu- 10km S Küre 50km N Kastamonu Straßenrand, 1000mH, 21.05.1990. leg. Schulz (6w / HNHM); Kastamonu- 10km S Küre 50km N Kastamonu Straßenrand, 1000mH, 21.05.1990. leg. Schulz (6w / PCAS); K'radžali 29.05.1956. leg. R. Bielawski et A. Goljan Inst. Zool. PAN Warszawa nr. 49/56 (4w / HNHM); Kütahya, 30km SSE (39. 122N/ 30.080E) 1140mH 10.06.2004. leg. A. Schulz 147 (3w / PCAS, 3w / HNHM); Sarkisla 15rkm S., Prov. Sivas, (ca. 80km SW. Sivas), 1400mH, 19.05.1997. leg. A. Schulz, K. Vock, M. Sanetra nr. 247 (12w / HNHM); Sultandaglani Mountains, vic. Cankurtaran, (38. 155N/31. 239E) 1750mH 10.05.2003. leg. A. Schulz (3w, 2q / PCAS, 6w, 2g / HNHM); Tasacu, Silifke nr. TR 037 14.05.1990. leg. Gallé (10w / HNHM).