Tetramorium shivalikense sp. n.

Bharti, Himender & Kumar, Rakesh, 2012, Taxonomic studies on genus Tetramorium Mayr (Hymenoptera, Formicidae) with report of two new species and three new records including a tramp species from India with a revised key, ZooKeys 207, pp. 11-35 : 13-16

Tetramorium shivalikense sp. n. Figs 1-3

Holotype.

Worker, India, Himachal Pradesh, Terrace, 31.928591°N, 75.931342°E, 420m alt., winkler, 11 October 2008, coll. R. Kumar, PUPAC.

Paratypes.

11(w), India, Himachal Pradesh, Terrace, 420m alt., winkler, 11 October 2008; 1(w), India, Punjab, Dharampur, 450m alt., beating, 14 October 2008; 18(w), India, Himachal Pradesh, Siholi, 550m alt., winkler, 19 October 2008; 1(w), India, Himachal Pradesh, Terrace, 420m alt., winkler, 25 May 2009; 1(w), India, Uttarakhand, Dehradun, Selaqui, 650m alt., 9 August 2009, winkler; 50(w), India, Uttarakhand, Dehradun, Forest Research Institute, 640m alt., hand picking, 14 August 2009; 1(w), India, Uttarakhand, Dehradun, Forest Research Institute, 640m alt., winkler, 17 August 2009; 1(w), India, Himachal Pradesh, Terrace, 420m alt., pitfall trap, 24 September 2009; 4(w), India, Himachal Pradesh, Ghati, 450m alt., winkler, 27 September 2009; 2(w), India, Himachal Pradesh, Chanaur, 600m alt., winkler, 3 October 2009; 2(w), India, Himachal Pradesh, Andretta, 940m alt., winkler, 11June 2010; 8(w), India, Himachal Pradesh, Palampur, 1140m alt., winkler, 14 June 2010; 1 (w), India, Himachal Pradesh, Dattal, 940m alt., winkler, 16 June 2010; coll. R. Kumar; PUPAC and two paratypes will be deposited in BMNH.

Worker description.

Measurements: Holotype worker. HL 0.56, HW 0.52, SL 0.34, EL 0.13, WL 0.60, PW 0.38, PSL 0.13, PTL 0.14, PPL 0.19, PTW 0.20, PPW 0.23, PTH 0.20, PPH 0.20, CI 92.86, OI 25.00, SI 65.38, PSLI 23.21, PeNI 52.63, LPeI 70.00, DPeI 142.86, PpNI 60.53, LPpI 95.00, DPpI 121.05, PPI 115.00.

Paratype workers. HL 0.56-0.62, HW 0.52-0.56, SL 0.34-0.35, EL 0.13-0.14, WL 0.60-0.67, PW 0.38-0.42, PSL 0.13-0.14, PTL 0.13-0.14, PPL 0.19-0.23, PTW 0.20-0.23, PPW 0.23-0.25, PTH 0.20-0.21, PPH 0.20-0.21, CI 89.83-92.86, OI 24.53-25.00, SI 62.50-66.04, PSLI 22.03-23.21, PeNI 51.22-54.76, LPeI 61.90-70.00, DPeI 142.86-164.29, PpNI 59.52-60.98, LPpI 95.00-109.52, DPpI 108.70-125.00, PPI 108.70-119.05 (10 measured).

Head slightly longer than broad, sides almost straight with rounded posterolateral corners, slightly broader posteriorly than anteriorly; posterior head margin straight with shallow median notch; clypeus convex with steep apical half; anterior margin of clypeus entire without median notch; anterior margin of clypeus with a narrow transverse plate-like fringe and having convex anterior margin; mandibles triangular, masticatory margin of mandibles with large apical and preapical tooth; third tooth slightly smaller than the preapical tooth followed by 3-4 denticles; frontal lobes weakly developed and elevated laterally, frontal area indistinct; antennal scrobes shallow and broad; eye moderate in size, located laterally and at mid-length of head, composed of ca. 35-36 ommatidia; antennae slender, 12-segmented; scape short from posterior head margin by one fourth of its length; mesosoma slightly longer than head, broader anteriorly than posteriorly, dorsum convex; pro-mesonotal suture and metanotal groove indistinct; propodeal spine longer (PSL 0.13-0.14mm), acute, divergent, with tips upcurved; propodeal lobes roughly broadly triangular and acute; posterior declivity of propodeum short, concave; petiole with a short peduncle, node slightly broader than long in dorsal view; base of node longer than dorsal face in lateral view, weakly convex dorsum in lateral view; ventrally petiole downcurved along its length; postpetiole broader than long; base of first gastral tergite weakly concave behind the postpetiole, anterolateral corners rounded and not projecting forward as a pair of blunt teeth or horns which go round the sides of the posterior portion of the postpetiole, gaster oval.

Head longitudinally rugose with few cross-meshes up to vertex, posteriorly reticulate-rugose, interrugal space punctured and shiny; frontal carinae strongly developed and somewhat short to reach posterior head corners; mandibles longitudinally rugulose and interrugal space smooth and shiny; clypeus with a strong median carina continued to vertex and two weak lateral carinae; dorsum of mesosoma reticulate-rugose; sides of mesosoma rugo-reticulate but weaker sculptured than dorsum; dorsum of node with an unsculptured median longitudinal strip and sides with weak rugosity; dorsum of postpetiole smooth and shiny, sides with weak rugosity; propodeal declivity, gaster and legs smooth and shiny.

Body darker brown in most specimens and few specimens yellowish brown; Whole body coveredwith abundant, long, erect and short subdecumbent pilosity; antennal scapes and hind tibiae with short suberect hairs.

Etymology.

The specific epithet refers to the collection area.

Ecology.

This new species is widespread in the Shivalik range of the north-western Himalaya and was collected from soil and leaf litter.

Remarks.

This new species belongs to the ciliatum- species group ( Bolton 1977) which is distributed in the Oriental and Indo-Australian regions. The characteristics of this group are: antennae 12-segmented, sting appendage triangular or dentiform, anterior clypeal margin entire and not notched or indented medially, frontal carinae extending well beyond the level of the posterior margins of the eyes, propodeal spines long and usually strongly developed, never downcurved along their length, anterolateral gastral corners not projecting forward as a pair of blunt teeth or horns which go round the sides of the posterior portion of the postpetiole.

Tetramorium shivalikense sp. n. is somewhat allied to Tetramorium zypidum Bolton. However, it can be easily distinguished from Tetramorium zypidum by the following combination of characters: anterior margin of clypeus is entire and convex, petiolar node slightly broader than long in dorsal view while in Tetramorium zypidum theanterior clypeal margin is shallowly impressed medially and the petiolar node significantly longer than broad. Other significant characters of Tetramorium shivalikense sp. n. which differentiate it from Tetramorium zypidum include eyes located laterally at mid-length of the head, propodeal lobes broadly triangular and acute, SI 62.50-66.04, sides of postpetiole with weak rugosity, frontal carinae strongly developed and somewhat short to reach posterior head corners. In Tetramorium zypidum the eyes are situated in front of the middle of the sides of the head, the propodeal lobes narrowly triangular and acute, SI 69.00-75.00, sides of postpetiole smooth, and the frontal carinae extend to the posterior head corners and are weak behind the level of the eyes.