Crematogaster fraxatrix

Nothing is known about the biology of .

Identification
Hosoishi and Ogata (2014) - A member of the Crematogaster fraxatrix group. This species is similar to Crematogaster chhangi, but can be distinguished by the oval-shaped propodeal spiracles and weakly developed subpetiolar process in the worker caste.

Distribution
Southern Thailand and Malaysia (Peninsular and Borneo).

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

Castes
Known only from the worker caste.

Nomenclature

 * . Crematogaster fraxatrix Forel, 1911a: 28 (w.) BORNEO (East Malaysia: Sarawak).
 * Type-material: syntype workers (number not stated).
 * Type-locality: Malaysia: Sarawak (Haviland).
 * Type-depositories: MHNG, NHMB.
 * Combination in C. (Acrocoelia): Emery, 1922e: 151;
 * combination in C. (Crematogaster): Bolton, 1995b: 166.
 * Status as species: Wheeler, W.M. 1919e: 72; Emery, 1922e: 151; Chapman & Capco, 1951: 91, 101; Bolton, 1995b: 153; Pfeiffer, et al. 2011: 45; Hosoishi & Ogata, 2014: 63 (redescription); Khachonpisitsak, et al. 2020: 90.
 * Distribution: Malaysia (Peninsula, Sarawak), Thailand.

Worker
Hosoishi and Ogata (2014) - Measurements and indices. HW 0.7–0.98; HL 0.64–0.93; CI 105–114; SL 0.58–0.68; SI 69–91; EL 0.13–0.18; PW 0.37–0.62; WL 0.69–0.95; PSL 0.13–0.21; PtL 0.18–0.25; PtW 0.18–0.25; PtH 0.13–0.17; PpL 0.11–0.15; PpW 0.16–0.23; PtHI 65–74; PtWI 94–111; PpWI 123–155; WI 83–92 (thirteen workers measured).

Workers with weak polymorphism in size. Posterior corners of head rounded in smaller worker, but squared in larger workers. Anterior clypeal margin slightly concave in the median portion. Compound eyes not projecting beyond lateral margins of head in full face view. Scape reaching posterior corner of head. Antennal club 3-segmented. Pronotal dorsum with distinct ridges laterally. Mesonotal dorsum with lateral ridges. Mesonotum slightly higher than pronotum in larger workers in lateral view. Metanotal groove straight in dorsal view, deep and forming a concave region between mesonotum and propodeum. Propodeal spiracles dorso-ventrally oval, located on lateral sides of propodeum; the horizontal diameter slightly larger than the vertical diameter even in smaller workers. Propodeal spines long, directed upward and straight. Petiole broader in the middle portion. Subpetiolar process developed as small, blunt denticle. Postpetiole weakly bilobed, but without longitudinal median sulcus. Petiole slightly wider than postpetiole in dorsal view.

Sparsely hirsute with erect setae. Scape with abundant erect to suberect setae. Dorsal face of head with suberect setae. Clypeus with suberect setae; one pair of longer setae directed medially on anteriormost portion. Anterior clypeal margin with one single setae and one pair of longer setae, mixed with some shorter setae on the sides. Mesosoma with sparse erect setae. Fourth abdominal tergite with sparse erect to suberect setae.

Dorsal surface of head generally smooth and shining, but feeble rugulae between frontal carinae; longitudinal rugulae surrounding antennal sockets and on gena. Clypeus weakly striated with longitudinal rugulae. Pronotum striated with feeble rugulae. Mesonum weakly striated with feeble rugulae. Lateral surface of pronotum smooth and shining. Mesopleuron sculptured, but the central portion relatively smooth. Lateral surface of propodeum with feeble rugulae.

Body color reddish-brown to black.

Type Material
Hosoishi and Ogata (2014) - MALAYSIA: Sarawak, Borneo (Haviland). ,, examined. Lectotype worker by present designation: top specimen of three specimens of one pin.

References based on Global Ant Biodiversity Informatics

 * Blaimer B. B. 2012. Acrobat ants go global  Origin, evolution and systematics of the genus Crematogaster (Hymenoptera: Formicidae). Molecular Phylogenetics and Evolution 65: 421-436.
 * 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
 * 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.
 * 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.
 * Hosoishi S., and K. Ogata. 2014. Description and DNA barcoding of Crematogaster fraxatrix Forel, 1911 and two new closely related species from Cambodia and Indonesia (Hymenoptera, Formicidae). ZooKeys 374: 5768. doi:10.3897/zookeys.374.5874
 * 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.