Pheidole vulgaris, Eguchi, Katsuyuki, 2006

Eguchi, Katsuyuki, 2006, Six new species of Pheidole Westwood from North Vietnam (Hymenoptera, Formicidae), Revue Suisse de Zoologie 113 (1), pp. 115-131 : 115

Pheidole vulgaris sp. n.

Figs 6A-I

Pheidole sp. eg-111 : Yamane et al., 2003 (a list of local ant fauna); Bui & Eguchi, 2003 (a list of local fauna); Eguchi et al., 2004 (ecological study).

HOLOTYPE. - Major from colony Eg01-VN-155. Type locality: My Yen Commune Forest (21°35’N, 105°36’E), Na Hau Village, My Yen Commune, Thai Nguyen, Vietnam [K. Eguchi leg., 8/xi/2001]. Depository: IEBR.

PARATYPES. - 19 majors and 20 minors from the same colony to which the holotype belongs. Depository: IEBR, MHNG, MCZC, BMNH, NHMW, FSKU, ACEG.

NON-TYPE MATERIAL EXAMINED. - China: Guangxi: Dayaoshan N. R., Jinxiu [JRF, 1998, Bottle #Eg38-36]; Guangdong: Dawuling N. R., Maoming [JRF, 1997, Bottle #Eg38-38]; Hong Kong: Taipo Kau N. P., New Territories [JRF, 1993, Bottle #Eg38-31]. 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. (21°10’15.6-18.1”N, 106°43’09.6”-16.0E, ca. 370-415 m alt) [B&E03-41, -52, -56, -57]; Quang Ninh: Ky Thuong N. R. (21°11’14.9”N, 107°07’08.5”E, ca. 105 m alt.) [B&E03-73]; Vinh Phuc: Tam Dao N. P. (21°27’N, 105°38’E, 800-1100 m alt.) [Eg99-VN-002, -034, -043; Eg01-VN- 112]; Ha Tay (misspelled as “Ha Tai” on the labels excluding those of Eg01-VN-234): Ba Vi N. P. (21?03’N, 105?22’E, 400-800 m alt. [Eg99-VN-085, -089, -093, -103, -120; Eg01-VN-209, - 224, -234; Eg02-VN-027, -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- 0 79 (W. Jaitrong leg., 1997)]; Nakhonratchasima: Khao Yai N. P. [TH00-SKY-34]. India: Utter Pradesh: Rajaji N. P. [A. Schulz & K. Vock leg., 1996]. Eguchi’s informal species code “ Pheidole sp. eg-111 ” has been applied to these specimens.

DIAGNOSIS. - Vertex and vertexal lobe largely smooth, or with weak and interrupted rugoso-reticulation directing posterolateral corner of the lobes and rarely with interspaces punctured (major); head and promesonotal dome smooth and shining (minor); hypostoma with 2 conspicuous processes and one very low or vestigial process in addition to the process just mesal to mandibular base (major); EL<LASX (minor); promesonotal dome lacking a conspicuous prominence on its posterior declivity (major and minor).

DESCRIPTION. - Major: TL 2.5-3.4 mm, HL 1.18-1.38 mm, HW 1.06-1.21 mm, SL 0.60-0.68 mm, FI 0.81-0.94 mm, CI 86-91, SI 53-59, FI 75-81 (N=11); body deep yellowish brown or brown (rarely dark brown), often with paler alitrunk and or gaster; head in full-face view very weakly convex laterad, broadly concave posteromedially, in profile not impressed on vertex; dorsal surface of head variable in sculpture; frons obliquely rugose to largely smooth and shining with sparse interrupted and irregular rugulae; vertex and vertexal lobe largely smooth, or weakly and interruptedly rugose/rugoso-reticulate toward posterolateral corner of the lobes and rarely with interspaces punctured; frontal carina absent or at most vestigial just as rugulae; antennal scrobe absent; median part of clypeus almost smooth and shining, rarely with an evanescent median longitudinal carina; hypostoma with 2 conspicuous processes and one very low or vestigial process (a total of 3 median processes) in addition to the process just mesal to each mandibular base (lateral processes); lateral processes well-developed, as large as lateral ones of the three median processes; antenna with a 3- segmented club; scape exceeding midlength of head; EL ≥ LASX; LG 1.4-1.9 times as much as EL; promesonotal dome smooth and shining, often with several weak rugulae; the dome at most with an inconspicuous prominence on its posterior declivity; dorsolateral part of the dome only very weakly produced; mesopleuron and lateral face of propodeum weakly punctured, or largely smooth and shining; propodeal spine elongate-triangular, usually with a blunt apex, narrowly based; petiole much longer than postpetiole (excluding helcium); petiolar node in anterior view usually very weakly concave dorsally; postpetiole not massive, 1.6-2.0 times as broad as petiolar node; first gastral tergite very weakly punctured at least around its articulation with postpetiole.

Minor: TL 1.7-2.0 mm, HL 0.54-0.61 mm, HW 0.46-0.53 mm, SL 0.52-0.61 mm, ML 0.75-0.84 mm, FL 0.57-0.67 mm, CI 85-91, SI 108-117, FI 116-127 (N=11); body yellowish brown; head smooth and shining; preoccipital carina complete but weak dorsally; median part of clypeus smooth and shining, 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; EL<LASX; promesonotal dome largely smooth and shining, in profile without a prominence on its posterior declivity; mesopleuron punctured; lateral face of propodeum very weakly punctured or almost smooth; propodeal spine small, elongate-triangular, narrowly based; petiole much longer than postpetiole (excluding helcium); postpetiole somewhat globular but not massive, 1.7-2.1 times as broad as petiolar node; gaster smooth and shining.

REMARKS. - This species is very similar to P. rinae taipoana Wheeler and P. laevicolor sp. n. but well distinguishable from them by the following characteristics: the major of the latter two has a reticulate dorsum of the vertexal lobe; and the minor of the latter two has a maximal diameter of the eye that is as long as or a little longer than the 10th antennal segment. This species is also similar to P. woodmasoni (the type material deposited in MHNG was examined; the syntype minors presumably lost), but the major of the former is well distinguished from that of the latter by the following characteristics: head in full-face view only very weakly concave posteriorly, convexity of promesonotal dome relatively weak, and propodeal spine short and relatively broadly based in the latter.

DISTRIBUTION. - Widespread in the Indo-Chinese subregion: S. China, N. Vietnam, N. Thailand and India (Utter Pradesh).

BIONOMICS. - This species ranges from forest edges to well-develop forests, from lowlands to hilly areas (up to 1400 m alt. in N. Vietnam), and nests in the soil (see also Eguchi et al., 2004). Colony Eg01-VN-112 includes dozens of dealate queens. This species probably forms super-colonies at least occasionally.