Crematogaster ebenina

Identification
Hosoishi (2015) - This species is unique among the Asian members of the Crematogaster ranavalonae-group in having a slender petiole. This species is similar to Crematogaster tumidula, but distinguished in having the petiole without anterolateral corners.

Distribution based on Regional Taxon Lists
Oriental Region: India, Myanmar. Palaearctic Region: China.

Nomenclature

 *  ebenina. Crematogaster (Oxygyne) ebenina Forel, 1902c: 199 (w.q.) INDIA. Senior synonym of corax:Hosoishi, 2015: 78.
 * corax. Crematogaster ebenina var. corax Forel, 1902c: 200 (w.) MYANMAR. Combination in C. (Oxygyne): Forel, 1903a: 683. Junior synonym of ebenina: Hosoishi, 2015: 78.

Worker
Hosoishi (2015) - (n = 4) HW 0.85-0.94; HL 0.81-0.86; CI 105-109; SL 0.69-0.76; SI 78-82; EL 0.18-0.19; PW 0.51-0.56; WL 0.98-1.05; PSL 0.11-0.13; PtL 0.24-0.26; PtW 0.24-0.27; PtH 0.16-0.17; PpL 0.14-0.16; PpW 0.24- 0.26; PtHI 64-67; PtWI 100-113; PpWI 162-173; WI 96-100.

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 or as long as width of scape in length. Compound eye large and slightly projecting beyond lateral margin of head in full face view.

Ventrolateral katepisternal ridge indistinct. Propodeal spine long and stout; length equal to slightly greater than diameter of propodeal spiracle, directed upward, dorsum as high as anterior propodeum. Propodeal spiracle large and situated close to propodeal declivity in lateral view, directed posterolaterally.

In dorsal view, shape of petiole scoop with convex side, longer than broad. Anterolateral corner of petiole undeveloped, tapering anteriorly. Petiolar spiracle big, as large as half of propodeal spiracle in diameter. Postpetiole weakly bilobed but without longitudinal median sulcus. Petiole slightly wider than, or as wide as postpetiole in dorsal view. Integument essentially smooth and shiny. Clypeus generally smooth and shiny, but with feable rugulae. Malar region smooth and shiny without rugulae. Dorsal surface of promesonotum smooth and shiny. Lateral surface of pronotum smooth and shiny. Mesopleuron and lateral propodeum generally shiny, but with feable rugulae. Dorsal surface of propodeum smooth and shiny.

Erect pilosity almost absent. Dorsum of head, clypeus and mesosoma with short and appressed sparse setae. Clypeus without longer setae on anteriormost portion. Anterior clypeal margin with one single longer setae and two pairs of longer setae, mixed with some shorter setae on the side. No erect setae on pronotal shoulder. Posterolateral tubercle with some decumbent to appressed shorter setae. Ventral surface of petiole with appressed setae. Postpetiole with some shorter setae posteriorly. 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
 * Fontanilla A. M., A. Nakamura, Z. Xu, M. Cao, R. L. Kitching, Y. Tang, and C. J. Burwell. 2019. Taxonomic and functional ant diversity along tropical, subtropical, and subalpine elevational transects in southwest China. Insects 10, 128; doi:10.3390/insects10050128
 * Forel A. 1902. Myrmicinae nouveaux de l'Inde et de Ceylan. Rev. Suisse Zool. 10: 165-249.
 * Forel A. 1903. Les Formicides de l'Empire des Indes et de Ceylan. Part X. J. Bombay Nat. Hist. Soc. 14: 679-715.
 * Guénard B., and R. R. Dunn. 2012. A checklist of the ants of China. Zootaxa 3558: 1-77.
 * HUANG Jian-hua, ZHOU Shan-yi. 2006. A Checklist of Family Formicidae of China - Myrmicinae (Part I) (Insecta: Hymenoptera). Journal of Guangxi Normal University. Natural science edition 24: 87-94.
 * 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.
 * Karmaly K. A.; S. Sumesh, T. P. Rabeesh, and L. Kishore. 2010. A checklist of ants of Thirunelli in Wayanad, Kerala. J. of the Bombay Natural History Society 107(1): 64-67.
 * Li Z.h. 2006. List of Chinese Insects. Volume 4. Sun Yat-sen University Press
 * Musthak Ali T. M. 1992. Ant Fauna of Karnataka-2. Newsletter of IUSSI Indian Chapter 6(1-2): 1-9.
 * Song Y., Z. Xu, C. Li, N. Zhang, L. Zhang, H. Jiang, and F. Mo. 2013. An Analysis on the Ant Fauna of the Nangun river Nature Reserve in Yunnan, China. Forest Research 26(6): 773-780.
 * Tiwari R. N., B. G. Kundu, S. Roy Chowdhury, and S. N. Ghosh. 2003. Insecta: Hymenoptera: Formicidae. Fauna of Sikkim. Part 4. State Fauna Series. 9.Zool.Surv.India. i-iii, 1-512. Chapter pagination: 467-506.
 * Tiwari R.N., B.G. Kundu, S. Roychowdhury, S.N. Ghosh. 1999. Insecta: Hymenoptera: Formicidae. Pp. 211-294 in: Director; Zoological Survey of India (ed.) 1999. Fauna of West Bengal. Part 8. Insecta (Trichoptera, Thysanoptera, Neuroptera, Hymenoptera and Anoplura). Calcutta: Zoological Survey of India, iv + 442 pp.
 * Wheeler W. M. 1927. Ants collected by Professor F. Silvestri in Indochina. Bollettino del Laboratorio di Zoologia Generale e Agraria della Reale Scuola Superiore d'Agricoltura. Portici 20: 83-106.
 * Wheeler W. M. 1928. Ants collected by Professor F. Silvestri in China. Bollettino del Laboratorio di Zoologia Generale e Agraria della Reale Scuola Superiore d'Agricoltura. Portici 22: 3-38.
 * Xu Z., Zeng G., Liu T.-Y. and He Y.-F.. 1999. [A study on communities of Formicidae ants in different subtypes of vegetation in Xishuangbanna District of China.] Zoological Research 20: 118-125