Crematogaster tumidula

This species is known from Malaysia (Borneo) and Indonesia (Kalimantan, Sumatra).

Identification
A member of the Crematogaster ranavalonae-group.

Hosoishi (2015) - This species is similar to Crematogaster ebenina, but differs in having developed anterolateral corners of the petiole. It is also similar to Crematogaster pia, but differs in having short and stout propodeal spines and the basal portion with smooth surface.

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

Nomenclature

 * . Crematogaster tumidula Emery, 1900d: 689, fig. 8 (w.) INDONESIA (Sumatra).
 * Type-material: lectotype worker (by designation of Hosoishi, 2015: 88), 1 paralectotype worker.
 * Type-locality: lectotype Indonesia: Sumatra, Pangherang Pisang (E. Modigliani); paralectotype with same data.
 * Type-depository: MSNG.
 * Combination in C. (Physocrema): Emery, 1922e: 140; Donisthorpe, 1941l: 226;
 * combination in C. (Oxygyne): Hosoishi & Ogata, 2009b: 33;
 * combination in C. (Crematogaster): Blaimer, 2012c: 55.
 * Status as species: Emery, 1922e: 140; Donisthorpe, 1941l: 226 (in key); Chapman & Capco, 1951: 103; Bolton, 1995b: 164; Hosoishi & Ogata, 2009b: 33; Pfeiffer, et al. 2011: 46; Hosoishi, 2015: 88 (redescription).
 * Distribution: Indonesia (Kalimantan, Sumatra), Malaysia (Sarawak).

Worker
Hosoishi (2015) - (workers, n = 10). HW 0.73-0.88; HL 0.72-0.86; CI 101-107; SL 0.60-0.77; SI 80-88; EL 0.15-0.19; PW 0.43-0.53; WL 0.80-0.97; PSL 0.08-0.12; PtL 0.20-0.26; PtW 0.23-0.27; PtH 0.14-0.18; PpL 0.14-0.22; PpW 0.20- 0.28; PtHI 54-68; PtWI 89-113; PpWI 125-178; WI 88-118.

Head appearing subquadratic in front view. Mandible weakly striate, with four teeth, apical and subapical teeth large, basal two teeth smaller. Scape exceeding posterior corner of head, with appressed setae, each of which is less than width of scape in length. Compound eye large and slightly projecting beyond lateral margin of head in full face view.

Ventrolateral katepisternal ridge indistinct posteriorly. Propodeal spine short and stout; length as long as spiracle, directed posteriorly, dorsum as high as anterior propodeum; basal width smaller than spiracles in diameter. Propodeal spiracle large, situated close to propodeal declivity in lateral view, directed laterally or posterolaterally.

In dorsal view, shape of petiole scoop with convex side, longer than broad. Anterolateral corner of petiole developed. Petiolar spiracle as large as half of propodeal spiracle in diameter, directed laterally. Postpetiole bilobed but without longitudinal median sulcus. Postpetiole as wide as petiole in dorsal view.

Integument essentially smooth and shiny. Clypeus smooth and shiny without rugulae. Malar region smooth and shiny. Dorsal surface of promesonotum smooth and shiny. Lateral surface of pronotum smooth and shiny. Mesopleuron and lateral propodeum generally smooth, but with feable rugulae. Dorsal surface of propodeum smooth and shiny; anterior dorsum smooth without rugulae.

Erect pilosity almost absent. Dorsum of head, clypeus and mesosoma with short and appressed sparse setae. Clypeus with one pair of longer setae on anteriormost portion, directed medially. Anterior clypeal margin with two pairs of longer setae on median portion, mixed with some shorter setae on side. No erect setae on pronotal shoulder. Posterolateral tubercle with some appressed shorter setae. Ventral surface of petiole with appressed setae. Postpetiole with some appressed setae. Fourth abdominal tergite with appressed setae.

Body color reddish brown.

References based on Global Ant Biodiversity Informatics

 * Blaimer B. B. 2012. Untangling complex morphological variation: taxonomic revision of the subgenus Crematogaster (Oxygyne) in Madagascar, with insight into the evolution and biogeography of this enigmatic ant clade (Hymenoptera: Formicidae). Systematic Entomology 37: 240-260
 * Blaimer, B.. "Untangling complex morphological variation: taxonomic revision of the subgenus Crematogaster (Oxygyne) in Madagascar, with insight into the evolution and biogeography of this enigmatic ant clade (Hymenoptera: Formicidae)." Systematic Entomology 37 (2012): 240-260.
 * 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
 * Donisthorpe H. 1941. Description of a new species of Crematogaster Lund, subgenus Physocrema Forel, with a list of, and a key to, the known species of the subgenus. Entomologist 74: 225-227.
 * Emery C. Formiche raccolte da Elio Modigliani in Sumatra, Engano e Mentawei. Annali del Museo Civico di Storia Naturale 40: 661-722.
 * Emery, C.. "Formiche raccolte da Elio Modigliani in Sumatra, Engano e Mentawei." Annali del Museo Civico di Storia Naturale Giacomo Doria (Genova) (2) 20, no. 40 (1900): 661-722.
 * Hosoichi S., and K. Ogata. 2009. A taxonomic revision of the Asian endemic subgenus Physocrema of the genus Crematogaster (Hymenoptera: Formicidae). Zootaxa 2062: 15-36.
 * Hosoishi S. 2015. Revision of the Crematogaster ranavalonae-group in Asia, with description of two new species (Hymenoptera, Formicidae). Journal of Hymenoptera Research 42: 63-92.
 * Hosoishi S. and K. Ogata. 2009. A check list of the ant genus Crematogaster in Asia (Hymenoptera: Formicidae). Bull. Inst. Trop. Agr. Kyushu Univ. 32: 43-83.
 * 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