Pheidole zoceana Santschi

Eguchi, K., 2008, A revision of Northern Vietnamese species of the ant genus Pheidole (Insecta: Hymenoptera: Formicidae: Myrmicinae)., Zootaxa 1902, pp. 1-118 : 110-114

Pheidole zoceana Santschi

Figs. 31a-g

Pheidole noggii (sic!) var. zoceana Santschi , 1925: 83. Bui & Eguchi 2003: 9 (checklist). Syntypes: 3 majors & 7 minors, "Chine, Zo-ce, V. Piel, 19.7.24" [China], NHMB, examined.

Pheidole zoceana Santschi . Eguchi, Yamane & Zhou, 2007: 280-283 (raised to species, redescription of major & minor).

Other material examined: Vietnam: Lai Chau: Western slope of Mt. Fansipan, ca. 2100-2200 m alt. [Eg02-VN-322]; Lao Cai: Cat Cat (along a trail to Mt. Fansipan), ca. 1300-1400 m alt., Sa Pa [Eg02-VN-258, -262, -263, -266], Sa Seng (small fragment of limestone forest), Sa Pa [Eg02-VN-277]; Nghe An: Pu Hoat [T.V. Bui]. Thailand: Chiang Mai: Doi Suthep-Pui N.P., ca. 800-900 m alt. [Eg01-TH-099, -101]. Eguchi's informal species code " Pheidole sp. eg-159" and "sp. eg-164" have been applied to these specimens.

Worker measurements & indices: Major (n=4). - HL 1.09-1.20 mm; HW 0.93-1.12 mm; CI 85-93; SL 0.44-0.53 mm; SI 47-49; FL 0.65-0.67 mm; FI 59-70.

Minor (n=4). - HL 0.44-0.52 mm; HW 0.38-0.46 mm; CI 86-91; SL 0.41-0.46 mm; SI 97-108; FL 0.44-0.50 mm; FI 105-116.

Worker description

Major. - Head in lateral view not or weakly impressed on vertex; frons longitudinally rugose; anterior part of vertex longitudinally rugose or reticulate; posterior part of vertex and dorsal and dorsolateral faces of vertexal lobe reticulate; frontal carina absent or inconspicuous (present just as rugulae); antennal scrobe absent; median longitudinal carina of clypeus absent, or present but weak; submedian and lateral processes of hypostoma conspicuous; median process relatively developed but lower than submedian processes; outer surface of mandible (excluding area around the base) smooth or dimly rugose, sparsely bearing (very) short appressed hairs; antenna with a 3-segmented club; maximal diameter of eye longer than antennal segment X. Promesonotal dome in lateral view at most with an inconspicuous mound on its posterior slope; humerus of the dome weakly produced laterad; the dome at the humeri a little broader than or almost as broad as at the bottom. Petiole much longer than postpetiole (excluding helcium); postpetiole not massive. First gastral tergite smooth and shining except punctured area around its articulation with postpetiole, or rugoso-punctrued largely.

Minor. - Dorsum of head punctured, and often overlain by weak rugoso-reticulation; preoccipital carina inconspicuous or absent dorsally; median part of clypeus smooth or weakly rugoso-reticulate; median longitudinal carina very weak to weak, or absent; antenna with a 3-segmented club; scape usually exceeding posterior margin of head by the half length of antennal segment II or more; maximal diameter of eye almost as long as antennal segment X. Promesonotal dome in lateral view at most with an inconspicuous mound on its posterior slope; mediodorsal part of the dome variable in sculpture, dimly punctured to smooth sometimes with several rugulae, or rugoso-reticulate but never punctured densely; lateral face of the dome largely smooth; humeral area of the dome rugoso-reticulate or rugoso-punctate, in dorso-oblique view not or weakly produced; mesopleuron, metapleuron and lateral face of propodeum punctured, or sometimes smooth partly; propodeal spine elongate-triangular. Petiole much longer than postpetiole (excluding helcium); postpetiole not massive.

Recognition: This species is distinguished among Indo-Chinese species by the combination of the following characteristics: in the major frontal carina absent or inconspicuous (present just as rugulae); in the major median and submedian processes of hypostoma conspicuous; in the major and minor promesonotal dome in lateral view at most with an inconspicuous mound on its posterior slope; in the minor dorsum of head punctured; in the minor lateral face of promesonotal dome largely smooth; in the minor propodeal spine elongatetriangular.

The major of P. zoceana is morphologically very similar to that of P. parva Mayr and P. rabo Forel , but the minor of the former is distinguished from that of the latter two in which promesonotal dome is punctured entirely.

Distribution & bionomics: Known from Vietnam, China and Thailand. This species occurs along forest edges in hilly and mountainous areas, and nests in the soil.