Pheidole aglae

This species inhabits well-developed forests (including primary and well-recovered secondary forests) from lowlands to hill areas. It nests in rotting wood blocks and logs on the forest floor. I have never encountered colonies which include more than one dealate queen. (Eguchi 2001a) Heterick & Kitching (2022) collected this species in a pitfall trap within a lowland dipterocarp forest in Brunei.

Identification
Eguchi (2001a) - This relatively large-sized species, with 3-segmented antennal club, is recognisable among Indo-Malayan congeners by having minor's head with occipital carina forming a well-developed flange. The most similar species is the sympatric Pheidole cariniceps, but in the latter antennal scrobe of the major is margined below by a marked carina; propodeal spine of the major has broad base; prominence on posterior declivity of promesonotum, and dorsum of propodeum bears a pair of standing hairs in the minor. I could examine one syntype (minor) of Pheidole longicornis. Morphological similarity between the minor of P. aglae and that of P. longicornis strongly suggests their conspecificity. However, I could not confirm it, since major(s) which should be included in the type material of P. longicornis according to Emery's original description could not be examined.

Majors from Poring and Sayap Kinabalu have, in general, a deeper emargination on posterior margin of head than those from other localities in Borneo, although intermediate conditions occur when we observe all the available Bornean specimens.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Borneo, Indonesia, Malaysia, New Guinea, Philippines, Singapore. Oriental Region: Thailand.

Worker
Minor

Nomenclature

 *  aglae. Pheidole aglae Forel, 1913k: 32 (s.w.q.) INDONESIA (Java). Senior synonym of concordia, fusiformis: Eguchi, 2001a: 3. See also: Eguchi, 2001b: 27.
 * fusiformis. Pheidole exasperata var. fusiformis Viehmeyer, 1914d: 607 (s.w.m.) NEW GUINEA. Junior synonym of aglae: Eguchi, 2001a: 3.
 * polita. Pheidole exasperata var. polita Viehmeyer, 1914d: 606 (s.w.) SINGAPORE. [Junior primary homonym of polita Emery, above.] Replacement name: concordia Santschi, 1916d: 242.
 * concordia. Pheidole exasperata var. concordia Santschi, 1916d: 242. Relacement name for polita Viehmeyer, 1914d: 606. [Junior primary homonym of polita Emery, 1894c: 155.] Junior synonym of aglae: Eguchi, 2001a: 3.

Worker
Eguchi (2001a) - Major Measurements and indices (n=10): TL 3.5-4.6 mm, HL 1.51-1.98 mm, HW 1.33-1.71 mm, SL 1.08-1.17 mm, FL 1.47-1.60 mm, CI81-88, SI68-81, FI 94-113. Head broadest at 1/2-5/8 distance of head (as measured from the mid-point of a transverse line spanning the anteriormost and posteriormost projecting points, respectively (Fig. 4A), in profile weakly or hardly impressed on vertex (Fig. 4C). Hypostoma bearing three low median processes. Clypeus rarely with a median longitudinal carina, with anterior margin emarginate medially. Eye situated at about 1/3 distance of head; distance between mandibular insertion and anterior margin of eye 1.4-1.8 times as long as maximal diameter of eye. Frontal carina distinct, extending backward to 7/10-3/4 distance of head (Fig. 4A). Antennal scrobe very weak, running along frontal carina. Antenna with 3-segmented club; scape extending backward to about 3/4 distance of head; terminal segment ca. 0.8 times as long as preceding two segments together. Masticatory margin of mandible with apical and preapical teeth, and a denticle in front of basal angle. Promesonotal dome with a distinct prominence on its posterior declivity (Fig. 40); the prominence in anterior view not concave medially. Mesopleuron with an inconspicuous transverse impression, or without impression. Propodeal spine horn-like, straight or slightly curved, with narrow base, 3.5-4 times as long as diameter of propodeal spiracle. Petiole in profile cuneiform, 1.2-1.4 times as long as postpetiole (excluding helcium); petiolar node in posterior view not or very weakly emarginate at apex. Postpetiole in dorsal view subpentagonal, 2.1-2.5 times as broad as petiolar node.

Frons to vertex longitudinally rugose; dorsal and lateral faces of occipital lobe reticulate; promesonotum in dorsal view transversely rugose, with smooth and shining interspaces; mesopleuron and lateral face of propodeum weakly rugoso-reticulate, with punctured enclosures; lateral face of petiole weakly punctured; dorsum of petiole smooth and shining; postpetiole and anterior part of first gastral tergite usually weakly or very weakly punctured. Outer face of mandible covered with relatively long decumbent hairs, which are 0.08-0.10 mm in length and almost as long as distance between piligerous punctures. Body brown, reddish-brown or dark reddish-brown, with a little darker abdomen; flagella and tarsi lighter than alitrunk.

Minor Measurements and indices (n=10): TL 2.7-3.0 mm, HL 0.77-0.91 mm, HW 0.55-0.65 mm, SL 1.07-1.30 mm, AL 1.14-1.33 mm, FL 1.18-1.45 mm, CI 69-73, SI 187-202, FI 209-225. Head in full-face view oval; occipital carina forming a well-developed flange (Fig. 4E, F). Clypeus without a median longitudinal carina (or rarely with inconspicuous carina), with anterior margin in full-face view truncate medially. Eyes situated just in front of midlength of head; distance between mandibular insertion and anterior margin of eye 0.9-1.0 times as long as maximal diameter of eye. Frontal carina and antennal scrobe present only around antennal insertion. Antenna with 3-segmented club; in full-face view scape extending beyond posterior border of head by more than its 1/3 length; terminal segment 0.7-0.8 times as long as preceding two segments together. Promesonotal dome with a low prominence on its posterior declivity (Fig. 4G). Mesopleuron without a transverse impression. Propodeal spine elongate-triangular, 1.5-2.5 times as long as diameter of propodeal spiracle. Petiole in profile cuneiform, 1.2-1.3 times as long as postpetiole (excluding helcium); petiolar node low, in posterior view not emarginate at apex. Postpetiole in dorsal view subpentagonal, ca. 2.0 times as broad as petiolar node.

Area between antennal insertion and eye weakly punctured; c1ypeus smooth and shining, or very weakly punctured; remainder of head smooth and shining (rarely punctured weakly); promesonotal dome smooth and shining, or concentrically puncto-rugose in dorsal view; remainder of alitrunk punctured; lateral face of petiole punctured; dorsum of petiole, and postpetiole and gaster almost smooth and shining. Prominence on posterior declivity of promesonotum, and dorsum of propodeum in profile each bearing at least two pairs of standing hairs. Body colour pattern similar to that of the major.

Type Material
Eguchi (2001b) - major, minor and queen; Bogor, Java. Five syntypes (2 majors and 3 minors, ) were examined, of which one major is designated as the lectotype.

References based on Global Ant Biodiversity Informatics

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