Anillomyrma decamera

Eguchi et al. (2009) - K. Eguchi and V.T. Bui collected workers of Anillomyrma decamera in a well-developed dry forest in the southern coastal part of Vietnam, by underground bait-trapping; baits (pork sausage) were buried in sandy soil. On the other hand, J. Caceres, a colleague of D.M. General, collected A. decamera in abandoned agricultural land that had isolated stands of abaca plants (Musaceae: Musa textilis NÉE) and jackfruit trees (Moraceae: Artocarpus heterophyllus LAM.), and was overgrown with tall grasses, upright and creeping bamboos and tree ferns. Ant samples were obtained by sifting a soil core sample taken from a deep sandy loam of volcanic origin. Bolton (1987) collected A. tridens on sandy ground in a lowland rain forest. These facts suggest that the distribution of this species may be affected by soil type. Emery (1901) mentioned that the type material of A. decamera was collected from termite nest(s). Anillomyrma may actively hunt soil invertebrates, including termites, using its well-developed sting to envenomate prey, and it may also scavenge animal matter under the ground.

Identification
Eguchi et al. (2009) - Body sculpture absent except for hair-pits, which are most conspicuous on head and pro-mesonotum; dorsum of head, promesonotum and gaster relatively densely covered with short suberect to decumbent hairs. Head in full-face view roughly rectangular, longer than broad; mandible with 4 distinct teeth of which basal one is smaller than the others and 3rd almost as large as 2nd (preapical tooth); antennal scape short, reaching only 7 / 10 - 3 / 4 of distance from anterior margin of clypeus to posterior margin of head; apical antennal segment more than 3 times as long as preapical segment. Dorsum of mesosoma in lateral view flat; posterior slope of propodeum in lateral view hardly expanding posterodorsad. Petiolar peduncle in lateral view gradually thickened toward node.

Anillomyrma tridens is morphologically very similar to Anillomyrma decamera. The only conspicuous morphological characters separating the two species are as follows: head slightly longer than broad, masticatory margin of mandible of A. tridens having 3 distinct teeth as mentioned by Bolton (1987) (but very small 4th tooth rarely present); the 3rd tooth of A. tridens much larger than 2nd; posterior slope of propodeum in lateral view ex-panding posterodorsad more strongly in A. tridens than in A. decamera; petiolar peduncle in lateral view more slender in A. tridens than in A. decamera.

Bolton (1987):


 * Mandible with 3 teeth, consisting of a large apical and preapical tooth which are close together, followed by a diastema and a large third (basal) tooth. (East Malaysia: Sarawak) . . . . . Anillomyrma tridens


 * Mandible with 4 teeth, consisting of a large apical and preapical tooth which are close together, followed by a diastema and a large third tooth, basal to which is a distinctly smaller fourth tooth . (Sri Lanka, India, Vietnam) . . . . . Anillomyrma decamera

Distribution
Eguchi et al. (2009) - India: Bihar (Bolton 1987). Sri Lanka: Anuradhapura. Vietnam: Ba Ria – Vung Tau; “Van Phu”. China: “Jungshan”. Philippines: Luzon.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Philippines. Oriental Region: India, Sri Lanka, Taiwan, Vietnam. Palaearctic Region: China.

Biology
Very rare subterranean ants.

Hosoishi et al. (2015) collected workers of this species by Winkler extraction in a lowland forest in Koh Kong Province, Cambodia. Among the Indochinese fauna, A. decamera is known from Vietnam (Eguchi et al., 2011). The collected specimens agree well with the description of A. decamera in having the 4-toothed masticatory margin of the mandible, and the posterior slope of propodeum weakly expanding posterodorsad (Eguchi et al., 2011).

Male
Yamane & Jaitrong (2019): The male is characterized by the following features:
 * large body size
 * heavily constructed body
 * virtual lack of propodeal lobe
 * small spiculum on anterior margin of abdominal sternum IX
 * relatively large abdominal segment III (postpetiole) that is broadly attached to segment IV

Nomenclature

 * . Monomorium decamerum Emery, 1901e: 117 (w.) SRI LANKA.
 * [Misspelled as decacrema by Sparks, et al. 2019: 228, in fig.]
 * Yamane & Jaitrong, 2019: 9 (m.).
 * Combination in Monomorium (Anillomyrma): Emery, 1913b: 261;
 * combination in Anillomyrma: Ettershank, 1966: 98.
 * Status as species: Forel, 1903a: 687; Emery, 1922e: 184; Chapman & Capco, 1951: 161; Ettershank, 1966: 98; Bolton, 1987: 274; Bolton, 1995b: 63; Eguchi, et al. 2009: 33 (redescription); Guénard & Dunn, 2012: 39; Terayama, Lin & Eguchi, 2012: 2; Bharti, Guénard, et al. 2016: 33; Yamane & Jaitrong, 2019: 9.
 * Senior synonym of continentis: Eguchi, et al. 2009: 33.
 * continentis. Anillomyrma decamera subsp. continentis Wheeler, W.M. 1927h: 96 (w.) VIETNAM.
 * Subspecies of decamera: Wheeler, W.M. 1928c: 20; Wheeler, W.M. 1930h: 67; Chapman & Capco, 1951: 161; Ettershank, 1966: 98.
 * Junior synonym of decamera: Eguchi, et al. 2009: 33.

Worker
Eguchi et al. (2009) - Type material (3 syntype workers of “Anillomyrma decamera ssp. continentis”, but 2 measured for PW and WL): CI 79 - 82, HL 0.34 - 0.35 mm, HW 0.27 - 0.29 mm, PW 0.19 mm, SI 66 - 67, SL 0.18 - 0.19 mm, WL 0.46 - 0.48 mm; Vietnamese material (5 workers from BTN16xii08-18): CI 80 - 83, HL 0.37 - 0.38 mm, HW 0.30 - 0.32 mm, PW 0.21 - 0.23 mm, SI 67 - 72, SL 0.21 - 0.22 mm, WL 0.46 - 0.48 mm; Philippine material (3 workers from Isarog): CI 83 - 87, HL 0.33 - 0.37 mm, HW 0.28 - 0.32 mm, PW 0.19 - 0.22 mm, SI 61 - 65, SL 0.18 - 0.19 mm, WL 0.43 - 0.47 mm; Chinese material (3 workers from Jungshan, but 2 measured for WL): CI 85 - 86, HL 0.34 - 0.35 mm, HW 0.29 - 0.30 mm, PW 0.20 - 0.22 mm, SI 66 - 67, SL 0.20 mm, WL 0.47 mm.

Type Material
Eguchi et al. (2009) - Syntype workers, Sri Lanka: Anuradhapura, W. Horn leg., 1899,. Two syntypes examined.

References based on Global Ant Biodiversity Informatics

 * Bolton B. 1987. A review of the Solenopsis genus-group and revision of Afrotropical Monomorium Mayr (Hymenoptera: Formicidae). Bulletin of the British Museum (Natural History). Entomology 54: 263-452.
 * 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
 * Dias R. K. S. 2002. Current knowledge on ants of Sri Lanka. ANeT Newsletter 4: 17- 21.
 * Dias R. K. S. 2006. Current taxonomic status of ants (Hymenoptera: Formicidae) in Sri Lanka. The Fauna of Sri Lanka: 43-52. Bambaradeniya, C.N.B. (Editor), 2006. Fauna of Sri Lanka: Status of Taxonomy, Research and Conservation. The World Conservation Union, Colombo, Sri Lanka & Government of Sri Lanka. viii + 308pp.
 * Dias R. K. S., K. R. K. A. Kosgamage, and H. A. W. S. Peiris. 2012. The Taxonomy and Conservation Status of Ants (Order: Hymenoptera, Family: Formicidae) in Sri Lanka. In: The National Red List 2012 of Sri Lanka; Conservation Status of the Fauna and Flora. Weerakoon, D.K. & S. Wijesundara Eds., Ministry of Environment, Colombo, Sri Lanka. p11-19.
 * Eguchi K.; Bui T. V.; Yamane S. 2011. Generic synopsis of the Formicidae of Vietnam (Insecta: Hymenoptera), part I  Myrmicinae and Pseudomyrmecinae. Zootaxa 2878: 1-61.
 * Eguchi K.; Bui, T. V.; General, D. M.; Alpert, G. D. 2010. Revision of the ant genus Anillomyrma Emery, 1913 (Hymenoptera: Formicidae: Myrmicinae: Solenopsidini). Myrmecological News 13:31-36.
 * Emery C. 1901. Ameisen gesammelt in Ceylon von Dr. W. Horn 1899. Deutsche Entomologische Zeitschrift 1901: 113-122.
 * Ettershank G. 1966. A generic revision of the world Myrmicinae related to Solenopsis and Pheidologeton (Hymenoptera: Formicidae). Aust. J. Zool. 14: 73-171.
 * Forel A. 1903. Les Formicides de l'Empire des Indes et de Ceylan. Part X. J. Bombay Nat. Hist. Soc. 14: 679-715.
 * Li Z.h. 2006. List of Chinese Insects. Volume 4. Sun Yat-sen University Press
 * Terayama M., C. C. Lin, and K. Eguchi. 2012. Additions to knowledge of the ant fauna of Taiwan (Hymenoptera, Formicidae, Solenopsidini): genera Anillomyrma and Carebara. Jpn. J. Syst. Ent. 18(1): 1-6.
 * Terayama, M. 2009. A synopsis of the family Formicidae of Taiwan (Insecta; Hymenoptera). The Research Bulletin of Kanto Gakuen University 17: 81-266.
 * 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. 1936. Ecological relations of ponerine and other ants to termites. Proceedings of the American Academy of Arts and Sciences. 71: 159-243.
 * Yamane S., and W. Jaitrong. 2019. Discovery of the male of the ant genus Anillomyrma (Emery, 1913) (Hymenoptera: Formicidae: Myrmicinae). Japanese Journal of Systematic Entomology 25 (1): 9–14.