Aenictus dentatus

According to Annette et al. (2003) in Pasoh, Malay Peninsula, Aenictus dentatus foraged on the forest floor in the day and night and preyed on ants of the genus Pheidole. We found this species preying on the ants of the genus Nylanderia in Lambir National Park, Sarawak (SR04-SKY-11). This species occurs from the sea level to highlands (up to 1,300 m a.s.l., Bodong Jaya, southern Sumatra) and inhabits primary and disturbed forests. (Jaitrong, Yamane and Wattanachai 2012)

Identification
A member of the pachycerus group. Jaitrong, Yamane and Wattanachai (2012) - In several characters variation is found that may or may not be of geographic nature. The subpetiolar process varies from low (its ventral outline weakly convex as seen in the Sumatran population and some colonies collected from Borneo such as Eg96-BOR-475, SB96-SKY-26 and SR04-SKY-11) to subtriangular (apex directed down-ward as seen in the type series and some colonies collected from Borneo such as Eg96-BOR-324 and Eg-BOR-545, and the single colony collected by Sk. Yamane from East Kalimantan). Size variation occurs between populations; the specimens from Sumatra are slightly larger than the type series (HW 0.80 - 0.85 mm vs. 0.72 - 0.78 mm). Within the Bornean population the variation in head width is greater: 0.75 mm to 0.88 mm. The specimens collected from Borneo tend to be darker in coloration than the lectotype and the other specimens from Malay Peninsula. However, in most of the characters the specimens from all parts of Sundaland agree with the type series, except for the single colony collected from West Java (FI95-676, SKYC and THNHM), in which the propodeal junction is simply right-angled, in profile not forming a overhanging tooth.

Aenictus paradentatus and Aenictus dentatus are very similar in general appearance as they share the distinctive coarse sculpture on head and mesosoma, and the relatively long antennal scape, extending beyond the posterior margin of the head. However, they differ in several significant characters. The antennal scape is relatively shorter in A. paradentatus (SI 117 - 124) than in A. dentatus (SI 143-152). No overlap is observed in HW / SL between the species. The posterior portion of the head in full-face view is relatively broader in A. paradentatus than in A. dentatus. The first gastral tergite is weakly shagreened with smooth interspaces in the former, while it is wholly smooth and shiny in the latter. The petiole has no peduncle in the former, but has a short but distinct peduncle in the latter.

Distribution
India, Malaysia and Borneo.

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

Biology
===Association with Other Organisms===



Castes
Known only from the worker caste.

Nomenclature

 * . Aenictus aitkeni var. dentata Forel, 1911d: 383 (w.) WEST MALAYSIA.
 * Type-material: lectotype worker (by designation of Jaitrong & Wiwatwitaya, 2013: 101), 5 paralectotype workers.
 * Type-locality: lectotype Malaysia: Berhentian Tingi (R. Martin); paralectotypes with same data.
 * [Note: original syntypes also included a series from Malaysia: Negri Sembilan (R. Martin), probably also in MHNG.]
 * Type-depository: MHNG.
 * Subspecies of aitkenii: Forel, 1913k: 20; Crawley, 1924: 389; Chapman & Capco, 1951: 10.
 * Status as species: Wilson, 1964a: 460; Terayama & Yamane, 1989: 598; Terayama & Kubota, 1993: 70; Xu, 1994a: 119; Bolton, 1995b: 59; Zhou & Chen, 1999: 63 (in key); Zhou, 2001b: 61; Jaitrong & Nabhitabhata, 2005: 11; Wang, W. 2006: 637 (in key); Pfeiffer, et al. 2011: 32; Bharti, Wachkoo & Kumar, 2012: 294 (in key); Guénard & Dunn, 2012: 22; Jaitrong, Yamane & Tasen, 2012: 134 (redescription); Jaitrong & Wiwatwitaya, 2013: 99 (in key); Bharti, Guénard, et al. 2016: 21.
 * Distribution: Brunei, India(?), Indonesia (Java, Kalimantan, Sumatra), Malaysia (Peninsula, Sabah, Sarawak), Thailand.

Worker
Wilson (1964) - Kuching: HW 0.76 mm, HL 0.92 mm, SL 1.09 mm. Other workers in this series have HW 0.78-0.81 mm. Bombay: HW 0.87 mm, HL L03 mm, SL 1.09 mm. Other workers in this series have HW 0.87-0.88 mm. Antenna 10-segmented. Mandibles typical. Clypeus convex, entire, unarmed. Parafrontal ridge prominent, about 0.5 mm long; prosalient and acutely angular in side view. Occiput convex, with a large, well demarcated collar. Propodeal junction developed into a high, thin transverse ridge which in side view appears as a large, acute "tooth" overhanging the declivitous face. Subpetiolar process a low, irregularly shaped lobe directed downward. Pilosity abundant and long; hairs on pronotum as long as 0.30 mm.

Head, mesosoma, and pedicel entirely microreticulate (reticular diameters about 0.01 mm) and opaque in Kuching series; in the Bombay series, a small area on the gena is feebly shining. In addition, lateral mesosomal surface bearing several longitudinal rugae, 5-6 in the Kuching series and about 10 in the Bombay series. Medium reddish brown overall, except for occiput, which is a somewhat contrasting dark reddish brown.

References based on Global Ant Biodiversity Informatics

 * Borowiec M. L. 2016. Generic revision of the ant subfamily Dorylinae (Hymenoptera, Formicidae). ZooKeys 608: 1–280.
 * 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
 * Chen Y. Q., Q. Li, Y. L. Chen, Z. X. Lu, X. Y. Zhou. 2011. Ant diversity and bio-indicators in land management of lac insect agroecosystem in Southwestern China. Biodivers. Conserv. 20: 3017-3038.
 * Cheng D., Z. Chen, and S. Zhou. 2015. An analysis on the ant fauna of Jinzhongshan Nature Reserve in Gunagxi, China. Journal of Guangxi Normal University: Natural Science Edition 33(3): 129.137.
 * Crawley W.C. 1924. Ants from Sumatra, with biological notes by Edward Jacobson. Annals and Magazine of Natural History (9)13: 380-409
 * Eguchi K., T. V. Bui, S. Yamane, H. Okido, and K. Ogata. 2004. Ant faunas of Ba Vi and Tam Dao, North Vietnam (Insecta: Hymenoptera: Formicidae). Bull. Inst. Trop. Agr. Kyushu Univ. 27: 77-98.
 * Eguchi K., and S. Yamane. 2003. Species diversity of ants (Hymenoptera, Formicidae) in a lowland rainforest, northwestern Borneo. New Entomol. 52(1,2): 49-59.
 * Guénard B., and R. R. Dunn. 2012. A checklist of the ants of China. Zootaxa 3558: 1-77.
 * Hashimoto Y., and S. Yamane. 1998. Army ants and ant collectors [1]--In quest of Asian army ants (Aenictinae) Insectarium 35: 4-8.
 * Herwina H., and K. Nakamura. 2007. Ant species diversity study using pitfall traps in a small yard in Bogor Botanic garden, West Java, Indonesia. Treubia 35: 99-116.
 * Hua Li-zhong. 2006. List of Chinese insects Vol. IV. Pages 262-273. Sun Yat-sen university Press, Guangzhou. 539 pages.
 * 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.
 * Jaitron W., and D. Wiwatwitaya. 2013. Two new species of the Aenictus pachycerus species group (Hymenoptera: Formicidae: Aenictinae) from southeast Asia. The Raffles Bulletin of Zoology 61(1): 97-102.
 * Jaitrong W. 2015. A revision of the Thai species of the ant genus Aenictus Shuckard, 1840 (Hymenoptera: Formicidae: Dorylinae). The Thailand Natural History Museum Journal 9(1): 1-94.
 * Jaitrong W., and T. Ting-Nga. 2005. Ant fauna of Peninsular Botanical Garden (Khao Chong), Trang Province, Southern Thailand (Hymenoptera: Formicidae). The Thailand Natural History Museum Journal 1(2): 137-147.
 * Jaitrong W.; Yamane, S.; Tasen, W. 2012. A sibling species of Aenictus dentatus Forel, 1911 (Hymenoptera: Formicidae) from continental Southeast Asia. Myrmecological News 16:133-138.
 * Jaitrong, W., S. Yamane, and W. Tasen. "A sibling species of Aenictus dentatus Forel, 1911 (Hymenoptera: Formicidae) from continental Southeast Asia." Myrmecological News 16 (2012): 133-138.
 * Li Z.h. 2006. List of Chinese Insects. Volume 4. Sun Yat-sen University Press
 * Malsch A. K. F., K. Rosciszewski, and U. Maschwitz. 2003. The ant species richness and diversity of a primary lowland rain forest, the Pasoh Forest reserve, West Malaysia. in T. Okuda, N. Manokaran, Y. Matsumoto, K. Niiyama, S. C. Thomas, and P. S. Ashton, eds. Pasoh: Ecology and Natural History of a Southeast Asin Lowland Tropical Rain Forest, pp 347-374.
 * Matsumoto T., T. Itioka, S. Yamane, and K. Momose. 2009. Traditional land use associated with swidden agriculture chnages encounter rates of the top predator, the army ant, in Southern Asian tropical rain forests. Biodivers. Conserv. 18: 3139-3151.
 * Ogata K. 2005. Asian ant inventory and international networks. Report on Insect inventory Project in Tropic Asia TAIIV: 145-170.
 * 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.; 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
 * Rizali A., M. M. Bos, D. Buchori, Sk. Yamane, and C. H. Schulze. 2008. Ants in tropical urban habitats: the myrmecofauna in a densely populated area of Bogor, West Java, Indonesia. Hayati Journal of Biosciences 15(2): 77-84.
 * Rizali A., M.M. Bos, D. Buchori, Sk. Yamane, C. Hans, and J. Schulze. 2008. Ants in tropical urban habitats: the myrmecofauna in a densely populated area of Bogor, West Java, Indonesia. Hayati Journal of Biosciences 77-84.
 * Terayama M., and S. Kubota. 1993. The army ant genus Aenictus (Hymenoptera: Formicidae) from Thailand and Viet Nam, with descriptions of three new species. Bulletin of the Biogeographical Society of Japan 48: 68-72.
 * Terayama M.; Yamane, S. 1989. The army ant genus Aenictus (Hymenoptera, Formicidae) from Sumatra, with descriptions of three new species. Japanese Journal of Entomology 57:597-603.
 * Wilson E. O. 1964. The true army ants of the Indo-Australian area (Hymenoptera: Formicidae: Dorylinae). Pacific Insects 6: 427-483.
 * Xu Z. 1994. A taxonomic study of the ant subfamily Dorylinae China (Hymenoptera Formicidae Ponerinae). Journal of Southwest Forestry College 14(2): 115-122
 * Yamane S.; Bui T. V.; Ogata K.; Okido H.; Eguchi K. 2002. Ant fauna of Cuc Phuong National Park, North Vietnam (Hymenoptera: Formicidae). Bulletin of the Institute of Tropical Agriculture Kyushu University 25: 51-62.
 * Yamane S.; Nona, A. R. 1994. Ants from Lambir Hills National Park, Sarawak. Pp. 222-226 in: Inoue, T.; Hamid, A. A. (eds.) 1994. Plant reproductive systems and animal seasonal dynamics. Long-term study of dipterocarp forests in Sarawak. Kyoto: Center for Ecological Research, Kyoto University, vii + 255 pp.
 * Zhang R. J., L. W. Liang, and S. Y. Zhou. 2014. An analysis on the ant fauna of Nonggang Nature Reserve in Guangxi, China. Journal of Guangxi Normal university: Natural Science Edition 32(3): 86-93.
 * Zhou S.-Y. and Chen Z. 1999. The ant genus Aenictus Shuckard from Guangxi (Hymenoptera: Formicidae). Guangxi Sciences 6(1): 63-64.
 * Zryanin V. A. 2011. An eco-faunistic review of ants (Hymenoptera: Formicidae). In: Structure and functions of soil communities of a monsoon tropical forest (Cat Tien National Park, southern Vietnam) / A.V. Tiunov (Editor). – M.: KMK Scientific Press. 2011. 277 р.101-124.