Pheidole rugifera

This species inhabits well-developed lowland forests, and nests in rotting wood.

Identification
Eguchi (2001) - P. rugifera is closely related to Pheidole maculifrons (known only from the Philippines), Pheidole tenebricosa, Pheidole clypeocornis, Pheidole kikutai and Pheidole hortensis, and all these are recognised among congeners by the characteristics noted under P. hortensis. Among the species known from Borneo, only P. rugifera and P. tenebricosa have punctured head and alitrunk in the minor. The major of the former is distinguishable from that of the latter in which mandible is rugose only around its base.

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

Nomenclature

 *  rugifera. Pheidole rugifera Eguchi, 2001b: 106, fig. 43 (s.w.) BORNEO.

Worker
Major (n=6): TL 1.9-2.2 mm, HL 0.84-0.94 mm, HW 0.77-0.84 mm, SL 0.38-0.40 mm, FL 0.46-0.49 mm, CI 89-92, SI 45-52, FI 55-63. Head broadest at about 1/2-3/5 distance of head (as measured from the mid-point of a transverse line spanning the anteriormost and posteriormost projecting points, respectively) (Fig. 43A), in profile weakly impressed on vertex (Fig. 43B). Hypostoma bearing one median process (rarely this process reduced in size). Clypeus without a median longitudinal carina, with anterior margin weakly concave medially; lateral part of clypeus weakly produced dorsally, but not developed into a horn as seen in P. clypeocornis sp. nov. 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. Frontal carina horizontal, extending backward to 3/5-2/3 distance of head (Fig. 43A). Antennal scrobe narrowly overhung by frontal carina. Antenna with 3-segmented club; scape extending backward to 1/2-3/5 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 two denticles in front of basal angle. Promesonotum forming a high dome, without a distinct prominence on its posterior declivity (Fig. 43C); each dorsolateral portion of the dome produced outward. Mesopleuron divided by a weak transverse impression into upper and lower parts. Propodeal spine triangular or elongate-triangular, almost twice as long as diameter of propodeal spiracle. Petiole 1.8-1.9 times as long as postpetiole (excluding helcium); petiolar node in posterior view not or slightly emarginate at apex. Postpetiole 1.5-1.8 times as broad as petiolar node.

Dorsum of head excluding occipital lobe longitudinally rugose, with interspaces punctured very weakly and shining; dorsal and dorsolateral faces of occipital lobe reticulate, with enclosures punctured very weakly and shining; outer face of mandible with rugulae running from mandibular base toward masticatory margin (Fig. 43A); dorsum of promesonotal dome weakly reticulate, with weakly punctured enclosures; lateral face of promesonotum weakly punctured or rugose; lower part of mesopleuron and declivitous face of propodeum largely smooth and shining; remainder of alitrunk largely punctured; ventral faces of midcoxa and hindcoxa distinctly reticulate; lateral face of petiole very weakly punctured; dorsum of petiole, and postpetiole and gaster smooth and shining. Outer face of mandible sparsely covered with very short appressed hairs (s 0.02 mm in length), which are much shorter than distance between piligerous punctures; submarginal zone of masticatory margin of mandible with a row of longer decumbent hairs. Body light brown to brown; antennae and legs lighter than alitrunk.

Minor (n=6): TL 1.3-1.4 mm, HL 0.42-0.44 mm, HW 0.38-0.41 mm, SL 0.35-0.37 mm, AL 0.52-0.55 mm, FL 0.36-0.39 mm, CI 90-94, 51 90-94, FI 96-93. Head in full-face view weakly concave posteriorly (Fig. 43D); occipital carina absent dorsally on head. Clypeus without a median longitudinal carina, with anterior margin in full-face view slightly convex 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. Frontal carina and antennal scrobe present only around antennal insertion. Antenna with 3-segmented club; scape slightly extending beyond posterior border of head; terminal segment 1.1-1.2 times as long as preceding two segments together. Promesonotal dome without a prominence on its posterior declivity (Fig. 43E). Mesopleuron without a distinct transverse impression. Propodeal spine ca. 1.5 times as long as diameter of propodeal spiracle. Petiole 1.8-2.0 times as long as postpetiole (excluding helcium); petioIar node in posterior view not emarginate at apex. Postpetiole in dorsal view, 1.5-1.6 times as broad as petiolar node.

Dorsum of head above subocular level including clypeus punctured; ventral face below subocular level smooth and shining; alitrunk punctured; lateral face of petiotar pedicel weakly punctured; dorsum of petiole, and postpetiole and gaster smooth and shining. Body brown with a little lighter gaster; antennae and legs lighter than alitrunk.

Type Material
Holotype Major, colony: Eg98-BOR-836, Lambir Hills N. P., near Miri, Sarawak, E. Malaysia (Borneo), K. Eguchi leg., 1998, deposited in. Paratypes 19 majors and 20 minors from the same colony to which the holotype belongs, deposited in, FRCK, , , , , , and.

References based on Global Ant Biodiversity Informatics

 * Eguchi K. 2001. A revision of the Bornean species of the ant genus Pheidole (Insecta: Hymenoptera: Formicidae: Myrmicinae). Tropics Monograph Series 2: 1-154.
 * Hashimoto Y., Y. Morimoto, E. S. Widodo, and M. Mohamed. 2006. Vertical distribution pattern of ants in a Bornean tropical rainforest (Hymenoptera: Formicidae). Sociobiology 47(3): 697- 710.
 * Kishimoto-Yamata K., F. Hyodo, M. Matsuoka, Y. Hashimoto, M. Kon, T. Ochi, S. Yamane, R. Ishii, and T. Itioka. 2012. Effects of remnant primary forests on ant and dung beetle species diversity in a secondary forest in Sarawak, Malaysia. Journal of Insect Conservation DOI 10.1007/s10841-012-9544-6
 * Mezger D., and M. Pfeiffer. 2011. Partitioning the impact of abiotic factors and spatial patterns on species richness and community structure of ground ant assemblages in four Bornean rainforests. Ecography 34: 39-48.
 * Mezger D., and M. Pfeiffer. 2011. Partitioning the impact of abiotic factors and spatial patterns on species richness and community structure of ground assemblages in four Bornean rainforest. Ecography 34: 39-48.
 * Pfeiffer M., D. Mezger, and J. Dyckmans. 2013. Trophic ecology of tropical leaf litter ants (Hymenoptera: Formicidae) - a stable isotope study in four types of Bornean rain forest. Myrmecological News 19: 31-41.
 * Pfeiffer M., and D. Mezger. 2012. Biodiversity Assessment in Incomplete Inventories: Leaf Litter Ant Communities in Several Types of Bornean Rain Forest. PLoS ONE 7(7): e40729. doi:10.1371/journal.pone.0040878
 * Pfeiffer M., and D. Mezger. 2012. Biodiversity Assessment in Incomplete Inventories: Leaf Litter Ant Communities in Several Types of Bornean Rain Forest. PLoS ONE 7(7): e40729. doi:10.1371/journal.pone.0040976
 * Pfeiffer M., and D. Mezger. 2012. Biodiversity Assessment in Incomplete Inventories: Leaf Litter Ant Communities in Several Types of Bornean Rain Forest. PLoS ONE 7(7): e40729. doi:10.1371/journal.pone.0041114
 * Pfeiffer M.; Mezger, D.; Hosoishi, S.; Bakhtiar, E. Y.; Kohout, R. J. 2011. The Formicidae of Borneo (Insecta: Hymenoptera): a preliminary species list. Asian Myrmecology 4:9-58
 * Watanasit S., S. Sonthichai, and N. Noon-anant. 2003. Preliminary survey of ants at Tarutao National Park, Southern Thailand. Songklanakarin J. Sci. Technol. 25(1) : 115-122