Pheidole sauberi

This species inhabits well-developed lowland and hill forests, and usually nests in rotting wood blocks on the ground.

Identification
Eguchi (2001) - P. sauberi is most closely related to Pheidole elisae, Pheidole sarawakana and Pheidole tandjongensis (see under P. elisae), and is sympatric with P. elisae and P. sarawakana in several localities. In P. elisae and P. sarawakana occipital lobe of the major is smooth and shining; and in P. sarawakana eye of both the subcastes is relatively small.

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

Worker
Minor

Major

Nomenclature

 *  sauberi. Pheidole sauberi Forel, 1905c: 18 (s.w.) INDONESIA (Java). See also: Eguchi, 2001a: 25; Eguchi, 2001b: 112.

Worker
Eguchi (2001a) - Major (n=7): TL 2.1-2.7 mm, HL 1.00-1.20 mm, HW 0.91-1.09 mm, SL 0.53-0.61 mm, FL 0.66-0.78 mm, CI 89-91, 51 53-59, FI 68-74. Head broadest at 3/5-2/3 distance of head (as measured from the mid-point of a transverse line spanning the anteriormost and posteriormost projecting points, respectively) (Fig. 46A), in profile not impressed on vertex (Fig. 46B). Hypostoma bearing a pair of median processes (Fig. 46C). Clypeus without 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 1.4-1.7 times as long as maximal diameter of eye; 6-7 ommatidia present on longest axis of eye. Frontal carina inconspicuous, extending backward to 3/5-2/3 distance of head. Antennal scrobe present only around antennal insertion. Antenna with 3-segmented club; antennal scape reaching about 3/5 distance of head; terminal segment 1.1-1.2 times as long as preceding two segments together. Masticatory margin of mandible with apical and pre apical teeth, and a denticle in front of basal angle. Promesonotum forming a high dome, without a prominence on its posterior declivity (Fig. 46D); each dorsolateral portion of the dome not produced outward. Mesopleuron divided by a transverse impression into two parts, of which lower part is distinctly margined dorsally. Propodeal spine horn-like, 2-2.5 times as long as diameter of propodeal spiracle. Petiole 1.8-2.0 times as long as postpetiole (excluding helcium); petiolar node high (Fig. 46D), in posterior view not emarginate at apex. Postpetiole high, 1.4-1.5 times as broad as petiolar node.

Dorsum of head completely covered with longitudinal rugulae (Fig. 46A; sometimes rugoso-reticulate around posterodorsal extremity of occipital lobe); lateral face of occipital lobe smooth and shining, or finely rugoso-punctured and dull; promesonotum smooth and shining, with several transverse rugulae dorsally; remainder of alitrunk smooth and shining, or weakly punctured; lateral faces of petiole and postpetiole weakly punctured; dorsa of petiole and postpetiole, and gaster smooth and shining. Outer face of mandible sparsely covered with decumbent hairs, which are 0.08-0.11 mm in length and much longer than distance between piligerous punctures. Body yellowish-brown, brown, reddish-brown or dark reddish-brown; antennae and legs a little lighter than alitrunk.

Minor (n=7): TL 1.4-1.8 mm, HL 0.48-0.58 mm, HW 0.43-0.51 mm, SL 0.47-0.56 mm, AL 0.63-0.75 mm, FL 0.50-0.61 mm, CI88-92, SI 102-112, FI 110-120. Head in full-face view almost straight posteriorly (Fig. 46E); occipital carina almost absent dorsally on bead. Clypeus without median longitudinal carina, with anterior margin in full-face view slightly convex or truncate medially. Eye situated just in front of midlength of head; distance between mandibular insertion and anterior margin of eye 0.8-0.9 times as long as maximal diameter of eye (Fig. 46F); 5-6 ommatidia present on longest axis of eye. Frontal carina sometimes present as an evanescent rugula which extends to 1/2-2/3 distance of head (as measured from anteriormost and posteriormost of head). Antennal scrobe present only around antennal insertion. Antenna with 3-segmented club; scape extending beyond posterior border of head by its 1/4-1/5 length; terminal segment 1.1-1.2 times as long as preceding two segments together. Promesonotum convex, without any prominence on its posterior declivity (Fig. 46G). Mesopleuron divided by transverse impression into two parts of which lower part is distinctly margined dorsally. Propodeal spine almost twice as long as diameter of propodeal spiracle. Petiole 1.9-2.0 times as long as postpetiole (excluding helcium); petiolar node high (Fig. 46G), in posterior view not emarginate at apex. Postpetiole high, 1.3-1.4 times as broad as petiolar node.

Gena with several rugulae; remainder of head including clypeus, and promesonotum smooth and shining; remainder of alitrunk smooth and shining, or weakly punctured partly; lateral face of petiole inconspicuously punctured; dorsum of petiole, and postpetiole and gaster smooth and shining. Body light yellowish-brown, light brown, brown or dark brown; flagella and legs a little lighter than alitrunk.

Type Material
Eguchi (2001b) - major and minor: Sarawak, Borneo. Six syntypes (3 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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