Pheidole smythiesii

This species usually inhabits woody habitats and sometimes occurs in open lands, and nests in the soil. According to Alfred & Agarwal (1990) workers tend aphid colonies (Micromyzus kalimponginsis) on Hedychium coronarium (Zingiberaceae) in Shillong, India. (Eguchi 2008)

Identification
Eguchi (2008) - There are no distinct differences between the syntypes of P. smythiesii and P. smythiesii bengalensis Forel. In Forel’s original description (Forel 1902), he mentioned that the head of the minor is longer in the latter than that in the former. The cephalic index is, however, not so different between them: CI 0.86 in the latter and CI 0.88–0.89 in the former. Thus P. smythiesii bengalensis is merely a local population of P. smythiesii. The differences between P. smythiesii and P. bhavanae shown by Bingham (1903) seem to be inadequate for separating them at the species level, and in the course of examination of the type material I also could not find definitive evidence which supports Bingham’s recognition of P. bhavanae from P. smythiesii. Thus I conclude that they are conspecific.

In Vietnam only two species, Pheidole smythiesii and Pheidole gatesi, have 4-segmented antennal clubs, and they are morphologically very similar to each other. Differences between the two species are given under the remarks of P. gatesi.

Key to Pheidole of North Vietnam

Distribution
Known from the Indian and Indo-Chinese subregions.

Distribution based on Regional Taxon Lists
Oriental Region: India, Nepal, Thailand, Vietnam. Palaearctic Region: China.

Nomenclature

 * bengalensis. Pheidole (Ceratopheidole) smythiesii var. bengalensis Forel, 1902c: 186 (w.) INDIA. Combination in Ceratopheidole: Emery, 1922e: 113; in Pheidole: Bolton, 1995b: 318. Junior synonym of smythiesii: Eguchi, 2008: 87.
 *  smythiesii. Pheidole (Ceratopheidole) smythiesii Forel, 1902c: 165 (s.), 185 (w.q.m.) INDIA. [Also described as new by Forel, 1902f: 38.] Combination in Ceratopheidole: Emery, 1922e: 113; in Pheidole: Bolton, 1995b: 330. Senior synonym of bengalensis, bhavanae: Eguchi, 2008: 87.
 * bhavanae. Pheidole bhavanae Bingham, 1903: 228 (s.w.) INDIA. Combination in Ceratopheidole: Emery, 1922e: 113; in Pheidole: Bolton, 1995b: 318. Junior synonym of smythiesii: Eguchi, 2008: 87.

Worker
Eguchi (2008) - Major (n=5). — HL 2.63–3.03 mm; HW 2.63–3.09 mm; CI 95–102; SL 1.34–1.46 mm; SI 45–53; FL 2.26–2.39 mm; FI 74–86. Minor (n=5). — HL 0.95–1.19 mm; HW 0.82–1.03 mm; CI 86–91; SL 1.13–1.33 mm; SI 124–140; FL 1.38–1.67 mm; FI 156–168.

Major — Head in lateral view usually not impressed on vertex; frons and vertex longitudinally-obliquely rugose; dorsal and dorsolateral faces of vertexal lobe rugoso-recticulate, rugoso-punctate or almost smooth; frontal carina and antennal scrobe absent; median longitudinal carina of clypeus weak or inconspicuous; median process of hypostoma low or inconspicuous, rarely with a concavity in the center; submedian processes low or relatively well developed (but rarely very low); lateral processes conspicuous (but sometimes small); antenna with a 4-segmented club; maximal diameter of eye almost as long as or a little longer than antennal segment X. Promesonotal dome in dorsal view smooth to shagreened, usually with transverse rugulae, in lateral view usually with a conspicuous prominence, but sometimes only with an inconspicuous mound on its posterior slope; humerus not produced; the dome narrower at the humeri than at the bottom. Petiole as long as or shorter than postpetiole (excluding its helcium); postpetiole massive. First gastral tergite shagreened to smooth.

Minor — Dorsum of head largely smooth or at most dimly punctured; preoccipital carina conspicuous dorsally and laterally; median part of clypeus smooth and shining; median longitudinal carina present at least anteriorly (but sometimes very weak); antenna with a 4-segmented club; scape extending far beyond postero-lateral margin of head; maximal diameter of eye shorter than (but rarely as long as) antennal segment X. Promesonotal dome smooth or shagreened, sometimes with weak rugulae, in lateral view with a low mound on its posterior slope; humerus in dorso-oblique view not raised; mesopleuron, metapleuron and lateral face of propodeum weakly punctured or almost smooth. Petiole much shorter than postpetiole (excluding helcium); postpetiole massive.

Type Material
Eguchi (2008):

Syntypes: 2 majors, 3 minors & 3 males, “Assam (Smythies) LXVII 8, 17 et 11.” [Assam, India],, examined; 1 major, “Assam (Smythies) LXVII 10”, MHNG, examined; 1 queen, “Assam Smythies XCV 4”, MHNG, examined.

Pheidole (Ceratopheidole) smythiesii var. bengalensis. Syntype: 1 minor, Bengal, India, MHNG, examined.

Syn.n. Syntypes: 1 major, “Sikkim Darjiling Senchal 8000ft 4. 1900 Bingham” [India; according to the original description Rogers collected the material],, examined; original description also included syntype minor(s) from the same locality, not examined.