Pheidole vulgaris Eguchi

Eguchi, K., 2008, A revision of Northern Vietnamese species of the ant genus Pheidole (Insecta: Hymenoptera: Formicidae: Myrmicinae)., Zootaxa 1902, pp. 1-118 : 103-104

Pheidole vulgaris Eguchi

Figs. 29a-g

Pheidole vulgaris Eguchi , 2006: 127-129. Holotype: major, My Yen Commune Forest, 21°35'N, 105°36'E, Na Hau Village, My Yen Commune, Thai Nguyen, Vietnam, Eg01-VN-155, IEBR, examined; paratypes: 19 majors & 20 minors, same data as holotype, IEBR, MHNG, MCZC, BMNH, FSKU & ACEG, examined. Pheidole sp. eg-111. Yamane et al. 2003: 58 (checklist), Bui & Eguchi 2003: 9 (checklist), Eguchi et al. 2004 (ecological study), Eguchi, Bui et al. 2005: 90 (checklist).

Other material examined: S. China: Guangxi: Dayaoshan N.R., Jinxiu [J. Fellowes]; Guangdong: Dawuling N.R., Maoming [J. Fellowes]; Da Qiao Town, Ruyuan County[Latella]; Hong Kong: Taipo Kau N.P., New Territories [J. Fellowes]. N. Vietnam: Lao Cai: Y Linh Ho (a small fragment of forest), ca. 1100 m alt., Sa Pa [Eg02-VN-214, -230]; Cat Cat (a trail to Mt. Phansipan), ca. 1300-1400 m alt., Sa Pa [Eg02-VN- 265]; Thai Nguyen: My Yen Commune Forest, 21°35'N, 105°36'E), Na Hau Village [Eg01-VN-155]; Bac Giang: W. Yen Tu N.P. (= Tay Yen Tu N.P.), 21°10-11'N, 106°43-44'E, 170 m alt. [Eg03-VN-079], W. Yen Tu N.P., 210 m alt. [Eg03-VN-063], W. Yen Tu N.P., 370 m alt. [B&E03-52, -56, -57; Eg03-VN-147], W. Yen Tu N.P., 400 m alt. [Eg04-VN-106], W. Yen Tu N.P., 415 m alt. [B&E03-41], W. Yen Tu N.P., 435 m alt. [Eg04-VN-144]; Quang Ninh: Chua Yen Tu, 21°09'N, 106°43'E, 520-725 m alt. [Eg04-VN-035]; Ky Thuong N.R., 21°11'N, 107°07'E, ca. 105 m alt. [B&E03-73], Ky Thuong N.R., 160 m alt. [Eg03-VN-166, -173, - 179, -181], Ky Thuong N.R., 220 m alt. [Eg03-VN-182]; Vinh Phuc: Tam Dao N.P., 21°27'N, 105°38'E, 800- 900 m alt. [Eg99-VN-034], Tam Dao N.P., 900 m alt. [Eg99-VN-002; Eg01-VN-112], Tam Dao N.P., 900- 1100 m alt. [Eg99-VN-043]; Ha Tay (part of specimens mislabeled as "Ha Tai"): Ba Vi N.P., 21°03'N, 105°22'E, 400-600 m alt. [Eg99-VN-085, -089, -093; Eg01-VN-209], Ba Vi N.P., 400-800 m alt. [Eg99-VN- 120], Ba Vi N.P., 600 m alt. [Eg99-VN-103], Ba Vi N.P., 670 m alt. [Eg01-VN-224, -234], Ba Vi N.P., 700 m alt. [Eg02-VN-027], Ba Vi N.P., 800 m alt. [Eg02-VN-048]; Ninh Binh: Cuc Phuong N.P., 20°14'N, 105°36'E, 320 m alt. [Eg01-VN-193, -195]. Thailand: Chiang Mai: Doi Suthep-Pui N.P., 800-900 m alt. [Eg01-TH-079 (W. Jaitrong leg., 1997)]; Nakhonratchasima: Khao Yai N.P., 900-1000 m alt. [TH00-SKY- 34]. India: Utter Pradesh: Rajaji N.P. [A. Schulz & K. Vock, 1996]. Eguchi's informal species code " Pheidole sp. eg-111" has been applied to these specimens.

Worker measurements & indices: Major (data from Eguchi 2006). - HL 1.18-1.38 mm; HW 1.06- 1.21 mm; CI 86-91; SL 0.60-0.68 mm; SI 53-59; FI 0.81-0.94 mm; FI 75-81.

Minor (data from Eguchi 2006). - HL 0.54-0.61 mm; HW 0.46-0.53 mm; CI 85-91; SL 0.52-0.61 mm; SI 108-117; FL 0.57-0.67 mm; FI 116-127.

Worker description

Major. - Body covered with relatively long standing hairs. Head in lateral view not or very weakly impressed on vertex; dorsal surface of head variable in sculpture; frons obliquely rugose or largely smooth with sparse interrupted and irregular rugulae; vertex and vertexal lobe largely smooth, or weakly and discontinuously rugose/rugoso-reticulate obliquely toward posterolateral corner of the lobes, often with the interspaces punctured; frontal carina absent or inconspicuous (present just as rugulae); antennal scrobe absent; clypeus sometimes with an evanescent or weak median longitudinal carina; hypostoma with a low or inconspicous median process and a pair of conspicuous submedian processes in addition to a pair of conspicuous lateral processes; outer surface of mandible smooth and shining excluding its basal area, and covered relatively long decumbent hairs; antenna with a 3-segmented club; eye consisting of usually more than 20 ommatidia(but sometimes less than 20 ommatidia); maximal diameter of eye almost as long as, or a little shorter or a little longer than antennal segment X. Promesonotal dome at most with an inconspicuous mound on its posterior slope; humerus of the dome only very weakly produced; the dome usually a little narrower, but sometimes a little broader (as seen in the holotype), at the humeri than at the bottom. Petiole (a little) longer than postpetiole (excluding helcium); postpetiole not massive. First gastral tergite very weakly punctured at least around its articulation with postpetiole, and smooth or sometimes shagreened in the remainder.

Minor. - Body yellowish-brown. Frons and vertex smooth and shining; preoccipital carina complete but weak dorsally; clypeus without a median longitudinal carina; antenna with a 3-segmented club; scape exceeding posterior margin of head by the length of second antennal segment or more; eye consisting of 12-18 ommatidia; maximal diameter of eye (a little) shorter than antennal segment X. Promesonotal dome largely smooth and shining, in lateral view without a mound on its posterior slope; humerus of the dome in dorsooblique view not produced; mesopleuron punctured; metapleuron and lateral face of propodeum weakly punctured or almost smooth; propodeal spine small, elongate-triangular. Petiole (a little) longer than postpetiole (excluding helcium); postpetiole not massive but relatively large, in lateral view somewhat globular.

Recognition: This species is characterized among Indo-Chinese species by the combination of the following features: in the major vertex and vertexal lobe largely smooth, or with weak and interrupted rugoso-reticulation directed towards the posterolateral corner of the lobes, often with interspaces punctured; in the minor head and promesonotal dome smooth and shining; in the major hypostoma with conspicuous submedian processes and one very low or vestigial median process; in the minor maximal diameter of eye (a little) shorter than antennal segment X; in the major and minor promesonotal dome lacking a conspicuous prominence/ mound on its posterior slope; in the major and minor petiole longer than postpetiole; in the major and minor postpetiole not massive.

This species is very similar to Pheidole taipoana Wheeler and P. laevicolor Eguchi but well distinguished from the latter two by the following characteristics: the major of the latter two having dorsum of vertexal lobe reticulate; the minor of the latter two having maximal diameter of eye a little longer than the length of antennal segment X. This species is also similar to Pheidole vieti (see under P. vieti ).

Distribution & bionomics: Known from Vietnam, S. China, Thailand and Utter Pradish. This species occurs from forest edges to well-developed forests, and nests in the soil (Eguchi et al. 2004). Colonies are at least occasionally polygynous.