Pheidole sarawakana

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

Identification
Eguchi (2001a) - P. sarawakana is most closely related to Pheidole elisae, Pheidole sauberi and Pheidole tandjongensis (see under P. elisae), and is sympatric with P. elisae and P. sauberi in several localities in Borneo. In P. sauberi dorsum of occipital lobe of the major is completely covered with longitudinal rugulae, and eye is relatively large (6-7 ommatidia on longest axis of eye in the major, and 5-6 in the minor); and in P. elisae eye is also relatively large (8 ommatidia on longest axis of eye in the major, and 6-7 in the minor).

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

Worker
Minor

Images from AntWeb
Major

Nomenclature

 *  sarawakana. Pheidole sauberi subsp. sarawakana Forel, 1911a: 45 (s.w.) BORNEO. Raised to species: Eguchi, 2001a: 23. See also: Eguchi, 2001b: 110.

Worker
Eguchi (2001a) - Major (n=7): TL 1.9-2.2 mm, HL 0.97-1.05 mm, HW 0.88-0.92 mm, SL 0.45-0.49 mm, FL 0.58-0.63 mm, CI 87-91, SI 51-54, FI 64-70. Head broadest at about 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. 45A), in profile not impressed on vertex (Fig. 45B). Hypostoma bearing a pair of median processes. 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 1.8-2.3 times as long as maximal diameter of eye; 4-5 ommatidia present on longest axis of eye. Frontal carina inconspicuous, extending backward to about midlength of head. Antennal scrobe present only around antennal insertion. Antenna with 3-segmented club; scape extending backward to about 3/5 distance of head; terminal segment 1.2-1.3 times as long as preceding two segments together. Masticatory margin of mandible with apical and preapical teeth, and a distinct denticle in front of basal angle. Promesonotum forming a high dome (Fig. 45C), in profile without a prominence on its posterior declivity; 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 elongate-triangular or horn-like, 2-2.5 times as long as diameter of propodeal spiracle. Petiole 1.9-2.0 times as long as postpetiole (excluding helcium); petiolar node high (Fig. 45C), in posterior view not emarginate at apex. Postpetiole high, 1.2-1.4 times as broad as petiolar node.

Dorsum of head excluding occipital lobe longitudinally rugose, with smooth and shining interspaces; occipital lobe smooth and shining (Fig. 45A); promesonotum smooth and shining, sometimes with several transverse rugulae dorsally; remainder of alitrunk largely smooth and shining, or mesopleuron and lateral face of propodeum weakly rugoso-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 appressed to decumbent hairs, which are 0.08-0.10 mm in length and much longer than distance between piligerous punctures. Head and alitrunk light brown; antennae, legs and gaster lighter than alitrunk.

Minor (n=7): TL 1.3-1.6 mm, HL 0.48-0.52 mm, HW 0.44-0.48 mm, SL 0.43-0.46 mm, AL 0.61-0.67 mm, FL 0.46-0.50 mm, CI 90-94, SI 95-99, FI 103-108. Head in full face view almost straight or slightly concave posteriorly (Fig. 45D); occipital carina almost absent dorsally on head. Clypeus without a median longitudinal carina, with anterior margin in full-face view truncate medially. Eye situated just in front of midlength of head; distance between mandibular insertion and anterior margin of eye 1.1-1.2 times as long as maximal diameter of eye; four ommatidia present on longest axis of eye. Frontal carina and antennal scrobe present only around antennal insertion. Antenna with 3-segmented club; scape extending beyond posterior border of head by its 1/6 length; terminal segment 1.2-1.3 times as long as preceding two segments together. Promesonotal dome without a prominence on its posterior declivity (Fig. 45E). Mesopleuron divided by a transverse impression into two parts, of which lower part is distinctly margined dorsally. Propodeal spine triangular, 1.5-2 times as long as diameter of propodeal spiracle. Petiole 1.9-2.0 times as long as postpetiole (excluding helcium); petiolar node high, in posterior view not emarginate at apex. Postpetiole high, 1.2-1.3 times as broad as petiolar node.

Head including clypeus and promesonotum smooth and shining; mesopleuron and lateral face of propodeum weakly punctured at least in part; petiole and postpetiole largely smooth and shining; gaster smooth and shining. Body light yellowish-brown to light brown; antennae and legs sometimes 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

 * Chapman, J. W., and Capco, S. R. 1951. Check list of the ants (Hymenoptera: Formicidae) of Asia. Monogr. Inst. Sci. Technol. Manila 1: 1-327
 * Eguchi K. 2001. A revision of the Bornean species of the ant genus Pheidole (Insecta: Hymenoptera: Formicidae: Myrmicinae). Tropics Monograph Series 2: 1-154.
 * Eguchi K. 2001. A taxonomic study on Asian Pheidole (Hymenoptera, Formicidae): new synonymy, rank changes, lectotype designations and redescriptions. Insecta Koreana 18: 1-35.
 * Eguchi K. 2003. A study on the male genitalia of some Asian species of Pheidole (Hymenoptera, Formicidae, Myrmicinae). Sociobiology 41: 317-355.
 * Eguchi, K. 2001. A revision of the Bornean species of the ant genus Pheidole (Insecta: Hymenoptera: Formicidae: Myrmicinae). Tropics Monogr. Ser. 2: 1-154.
 * Forel A. 1911. Fourmis de Bornéo, Singapore, Ceylan, etc. récoltées par MM. Haviland, Green, Winkler, Will, Hose, Roepke et Waldo. Rev. Suisse Zool. 19: 23-62.
 * 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.
 * Ito, F.; Yamane, S.; Eguchi, K.; Noerdjito, W. A.; Kahono, S.; Tsuji, K.; Ohkawara, K.; Yamauchi, K.; Nishida, T.; Nakamura, K. 2001. Ant species diversity in the Bogor Botanic Garden, West Java, Indonesia, with descriptions of two new species of the genus Leptanilla (Hymenoptera, Formicidae). Tropics 10:379-404.
 * Jaitrong W.; Nabhitabhata, J. 2005. A list of known ant species of Thailand. The Thailand Natural History Museum Journal 1(1): 9-54.
 * 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
 * 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
 * Wheeler W. M. 1919. The ants of Borneo. Bulletin of the Museum of Comparative Zoology 63:43-147.
 * Woodcock P., D. P. Edwards, R. J. Newton, C. Vun Khen, S. H. Bottrell, and K. C. Hamer. 2013. Impacts of Intensive Logging on the Trophic Organisation of Ant Communities in a Biodiversity Hotspot. PLoS ONE 8(4): e60756. doi:10.1371/journal.pone.0060756
 * Woodcock P., D. P. Edwards, T. M. Fayle, R. J. Newton, C. Vun Khen, S. H. Bottrell, and K. C. Hamer. 2011. The conservation value of South East Asia's highly degraded forests: evidence from leaf-litter ants. Phil. Trans. R. Soc. B. 366: 3256-3264.