Camponotus horseshoetus Datta & Raychaudhuri, 1985

Bharti, Himender & Wachkoo, Aijaz Ahmad, 2015, Neotype designation and redescription of Camponotus horseshoetus (Hymenoptera: Formicidae), Acta Entomologica Musei Nationalis Pragae 55 (1), pp. 381-385 : 383

Camponotus horseshoetus Datta & Raychaudhuri, 1985

( Figs 1–4 )

Camponotus horseshoetus Datta & Raychaudhuri, 1985: 271 , fig 1, pl. 1 (original description). Camponotus horseshoetus: BOLTON (1995) : 103 (subgenus indeterminate).

Type material. NEOTYPE: worker, INDIA: WEST BENGAL: Darjeeling , 27.0383°N 88.2620°E, 1850 m a.s.l., 20.vi.2009, hand collected ( PUAC: coll. Aijaz A. Wachkoo).

Additional material examined. 3 workers with the same data as neotype ; 9 workers, INDIA: HIMACHAL PRADESH: Baijnath , 32.0527°N 76.6500°E, 1125 m a.s.l., 17.vi.2010, hand collected ( PUAC: coll. Aijaz A. Wachkoo) .

Redescription. Worker measurements (n=9): HL 1.14–1.30; HW 0.98–1.15; EL 0.31–0.34; SL 0.97–1.03; PW 0.67–0.78; ML 1.44–1.73; MTL 0.94–1.03; HTL 1.14–1.18; PL 0.20–0.22; GL 1.89–1.95; TL 4.68–5.16 mm. Indices: CI 86.54–88.89, SI 89.58–98.78.

Head ovoid, slightly longer than wide, narrowed anteriorly, lateral margins gently convex, posterior margin convex; clypeus in full-face view wider than long, wider anteriorly; anterolateral corners broadly rounded, mandibles slender, armed with 5-teeth, their tips overlap and the entire blades are tucked away under the clypeus in such a way that only their external margins show along the anterior clypeal margin; scape surpassing posterior cephalic margin by about one-third its length.

Mesosomal outline in profile interrupted by deep metanotal groove; promesonotum forms a regular convexity with shallow impression at promesonotal suture, metanotum lower than promesonotum and propodeal dorsum; propodeum raised, dorsal margin forms right angle with declivity; metapleural gland orifice distinct; propodeal spiracle round; in profile petiole, subrectangular, with dorsal margin sloping anteriorly; anterior margin nearly straight; posterior margin broadly concave; dorsally seen petiolar summit strongly concave; sides angulate; hind tibiae round in cross section.

Head microreticulate; remainder of the body lightly microreticulate, appearing finely striate; mesosomal, petiolar and gastral striation transverse; mesopleuron longitudinally striate; scapes microreticulate; body shiny.

Body covered with very short and very sparse appressed pubescence; head and all gastral segments with erect long setae, denser on gaster; setae absent on mesosoma and petiole; metanotal orifice without guard setae.

Body black; antennae and legs with reddish tinge, first gastral tergite with two yellow- -brown spots anterolaterally.

Comparative diagnosis. This species is unusual in that it is only the second Southeast Asian species of Camponotus known to have a metapleural gland, the other being Camponotus gigas (Latreille, 1802) distributed in Thailand, Malaysia, Singapore, Borneo, and Sumatra ( SHATTUCK 2005, BOLTON et al. 2007). It can be easily distinguished from the latter by presence of deeply impressed metanotal groove; very sparse pubescence; metanotal orifice without tuft of guard setae and dorsally strongly concave petiole, whilst in Camponotus gigas mesosomal outline is smoothly arched in lateral view without any metanotal groove; body is covered with dense pubescence; metanotal orifice is covered with guard setae and petiole scale is dorsally convex. Distribution and habitat. This species seems to be widespread in Indian Himalaya although infrequent in collections. Previously it was known only from the Nagaland state of Northeast Himalaya ( DATTA & RAYCHAUDHURI 1985). Here we report its distribution both in the Northeast Himalaya (Darjeeling, West Bengal) and Northwest Himalaya (Baijnath, Himachal Pradesh). It was collected from tree branches. Our observations indicate that it is an arboreal forager, which confirms earlier observations of DATTA & RAYCHAUDHURI (1985) finding workers tending groups of Aphis gossypii Glover, 1877 on Hibiscus rosasinensis Linnaeus, 1753 .

Figures

Figs 1–4. Camponotus horseshoetus Datta & Raychaudhuri, 1985, worker. 1 – head, full face view. 2 – body, lateral view. 3 – body, dorsal view. 4 – metapleural gland orifice on posterior propodeum.