Pheidole montana

This species inhabits well-developed hill forests. I found its nests in the soil, and many colonies were collected from rotting logs by TK. (Eguchi 2001)

Identification
Eguchi (2001) - This species is closely related to Pheidole comata and Pheidole longipes, and all these are peculiar among Indo-Chinese and Indo-Malayan congeners in the characteristics noted under P. comata. Diagnostic characteristics of this species which separate it from P. longipes are: propodeal spine horn-like, more than 3.5 times as long as diameter of propodeal spiracle in the major and more than 4 times in the minor; in profile dorsum of promesonotal dome in front of the prominence on its posterior declivity bearing 10-20 standing hairs in the major. Body yellowish-brown to brown in the minor. This species is distinguished from P. comata by the characters noted under P. comata.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Borneo, Indonesia, Malaysia.

Nomenclature

 *  montana. Pheidole montana Eguchi, 1999: 100, figs. 8-11 (s.w.q.) BORNEO. See also: Eguchi, 2001b: 83.

Worker
Eguchi (2001) - Major (n=8): TL 5.8-6.3 mm, HL 2.37-2.70 mm, HW 2.32-2.53 mm, SL 1.60-1.72 mm, FL 2.63-2.87 mm, CI 93-100, SI 64-71, FI 108-117. Head broadest at 3/5-7/10 distance of head (as measured from the mid-point of a transverse line spanning the anteriormost and posteriormost projecting points, respectively; posterior margin of head in full-face view with median emargination from which an inconspicuous longitudinal impression extends to midlength of head (Fig. 31A); head in profile not impressed on vertex (Fig. 31B) Hypostoma without median processes. Clypeus with a median longitudinal carina, with anterior margin weakly emarginate medially. Eye situated around 1/3 distance of head; distance between mandibular insertion and anterior margin of eye 1.7-1.8 times as long as maximal diameter of eye. Frontal carina and antennal scrobe present only around antennal insertion. Antenna without conspicuous club; scape extending backward to 4/5 distance of head. Masticatory margin of mandible with apical and pre apical teeth, and a denticle in front of basal angle. Promesonotal dome with a distinct prominence on its posterior declivity (Fig. 31 C); the prominence in anterior view not or very weakly concave medially. Mesopleuron with an indistinct transverse impression. Propodeal spine corniform, 3.5-4 times as long as diameter of propodeal spiracle. Petiole in profile cuneiform, almost as long as postpetiole, with ill-defined node of which apex is in posterior view distinctly concave. Postpetiole in dorsal view subpentagonal, 2.2-2.5 times as broad as petiole.

Frons and gena longitudinally rugose; dorsum of occipital lobe with fine longitudinal rugulae curving outward, and with interspaces weakly punctured and dull; lateral face of occipital lobe finely and weakly rugose, sometimes with punctured interspaces; median portion of dorsolateral face of head rugoso-reticulate with enclosures punctured and dull; promesonotal dome smooth and shining; remainder of alitrunk largely punctured very weakly and shining; lateral faces of petiole and postpetiole very weakly punctured and shining; dorsa of petiole and postpetiole punctured very weakly, or smooth and shining; gaster smooth and shining. Dorsal face of head (including occipital lobe) and lateral face of occipital lobe bearing standing hairs (Fig. 31A); outer face of mandible sparsely covered with appressed to decumbent hairs, which are 0.05-0.08 mm in length and shorter than distance between piligerous punctures; submarginal zone of masticatory margin of mandible with a row of longer decumbent hairs; in profile dorsum of promesonotal dome in front of the prominence on its posterior declivity bearing 10-20 standing hairs (Fig. 31C). Body yellowish-brown, brown, or reddish-brown; legs lighter than alitrunk.

Minor (n=162): TL 3.5-4.8 mm, HL 0.92-1.42 mm, HW 0.62-0.99 mm, SL 1.28-1.95 mm, AL 1.27-1.93 mm, FL 1.57-2.51 mm, CI 64-73, SI 172-227, FI 226-280. Head in full-face view narrowed and prolonged behind eyes toward occipital carina which forms a distinct flange. Clypeus with a weak longitudinal median carina, with anterior margin slightly convex or truncate medially. Eye situated at 4/9-1/2 distance of head (as measured from anterior margin of clypeus to occipital carina); distance between mandibular insertion and anterior margin of eye 1.1-1.3 times as long as maximal diameter of eye. Antenna without conspicuous club, but 8th segment 1.3-1.4 times as long as 7th. Promesonotal dome with a distinct prominence on its posterior declivity (Fig. 31D). Mesopleuron without a distinct transverse impression. Propodeal spine 4-5 times as long as diameter of propodeal spiracle (Fig. 310). Petiole in profile cuneiform, with ill-defined node, 0.8-0.9 times as long as postpetiole. Postpetiole 2.2-2.3 times as broad as petiole, in dorsal view distinctly longer than broad, gently narrowed forward in its anterior 2/3.

Head including clypeus and promesonotum smooth and shining; remainder of alitrunk largely smooth (or very weakly punctured) and shining; lateral faces of petiole and postpetiole smooth and shining, or very weakly punctured; dorsa of petiole and postpetiole, and gaster smooth and shining. Body light brown to brown, with a little darker head and gaster.

Type Material
Eguchi (2001) - Major, minor and queen. Type locality: Mt. Kinabalu (nr. Park Headquarters, ca. 1500 malt.), Sabah, Borneo.