Acropyga butteli

LaPolla (2004) - It has been collected in rainforests from root mats, soil cores, and in rotten wood. Terayama et al. (2002) listed this species as occurring with the mealybug Eumyrmococcus nipponensis, but this record may be an error, as that mealybug was known previously only to be associated with Acropyga nipponensis, and its listing by Terayama et al. (2002) was not considered a new record.

Identification
LaPolla (2004) - Worker: 11 segmented antennae; mandible broad, with 5 teeth, basal tooth enlarged and rectangular, apically truncated; head width> 0.53mm. Queen: As in worker with modifications expected for caste. Male: 12 segmented antennae; mandible broad with 4 teeth; 3rd and basal tooth enlarged and rectangular, apically truncated, as in worker caste; digiti with rounded apices. Compare with Acropyga inezae and Acropyga nipponensis.

This species is fairly easy to recognize with its five teeth, rectangular, apically truncated basal tooth and large size (TL > 2.0mm). The types of A. amblyops (a synonym of A. butteli) are larger than other examined specimens placed in A. butteli and this may be indicative of a "composite species" as it is defined here. However I conclude splitting is unnecessary since the size variation observed in head and scape characteristics appears to represent a continuum rather than discrete morphological discontinuities and that if more specimens were measured the "gap" observed between the A. amblyops types and the other specimens would close. The synonymized species are only distinguishable by differences in size. Until male specimens associated with different sized workers indicate they are not conspecific, I consider A. butteli a single, variable species.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Borneo, Brunei Darussalam, Indonesia, Malaysia. Oriental Region: Laos, Taiwan, Vietnam.

Taiwan south to Indonesia.

Nomenclature

 *  butteli. Acropyga (Atopodon) butteli Forel, 1912m: 772 (q.) WEST MALAYSIA. [Also described as new by Forel, 1913k: 101.] Senior synonym of amblyops, baodaoensis, distinguenda, meermohri, termitobia: LaPolla, 2004a: 36.
 * termitobia. Acropyga (Atopodon) termitobia Forel, 1912m: 773 (q.) WEST MALAYSIA. [Also described as new by Forel, 1913k: 101.] Junior synonym of butteli: LaPolla, 2004a: 36.
 * amblyops. Acropyga (Atopodon) amblyops Forel, 1915a: 34 (w.) INDONESIA (Sumatra). Junior synonym of butteli: LaPolla, 2004a: 36.
 * meermohri. Atopodon meermohri Stärcke, 1930: 375, pl. 18, fig. oben (w.) INDONESIA (Palau I.). Combination in Acropyga: Bolton, 1995b: 57. Junior synonym of butteli: LaPolla, 2004a: 36.
 * distinguenda. Acropyga (Atopodon) distinguenda Karavaiev, 1935a: 110, fig. 28 (w.q.m.) VIETNAM. Junior synonym of butteli: LaPolla, 2004a: 36.
 * baodaoensis. Acropyga (Atopodon) baodaoensis Terayama, 1985b: 284, figs. 1-13 (w.q.m.) TAIWAN. Junior synonym of butteli: LaPolla, 2004a: 36. See also: Terayama, Fellowes & Zhou, 2002: 28.

Worker
LaPolla (2004) - (n=9): TL: 2.16-3.00; HW: 0.549-0.787; HL: 0.607-0.882; SL: 0.442- 0.522; ML: 0.555-0.643; GL: 0.965-1.49; CI: 81.46-90.44; SI: 66.33-83.16.

Head: yellow; covered in a thick layer of short appressed hairs; head distinctly longer than broad, often becoming narrower anteriorly; posterior margin slightly concave medially, sometimes with several short erect hairs; 11 segmented, slightly incrassate antennae; scape fails to reach posterior margin by about length of first two funicular segments, occasionally scape longer, failing posterior margin by about 1/2 length of pedicel; clypeus broad, convex medially, with many erect hairs; median portion of clypeal anterior margin slightly pointed giving clypeus a slight "beak-like" appearance; mandible broad, with 5 teeth; basal tooth enlarged and rectangular, apically truncated; anterior clypeal margin and inner mandibular margin nearly parallel. Mesosoma: yellow; in lateral view, pronotum rises steeply toward mesonotum; covered in layer of appressed hairs, long, erect hairs posteriorly placed; mesonotum nearly flat, about same height as propodeum; covered dorsally in a layer of appressed hairs, often with several short, erect to sub erect hairs scattered throughout; metanotal area often distinct; propodeum dorsum with appressed hairs; declivity steep, without hairs present. Gaster: yellow; covered in layer of appressed hairs with scattered erect to suberect hairs throughout.

Queen
LaPolla (2004) - (n=1): TL: 4.02; HW: 0.733; HL: 0.806; SL: 0.653; ML: 1.21; GL: 2.00; CI: 90.94; SI: 89.09.As in worker with modification expected for caste and the following differences: head and mesonotum with more erect hairs than in worker.

Male
LaPolla (2004) - (n=2): TL: 2.5-2.73; HW: 0.477-0.503; HW: 0.506-0.507; SL: 0.44-0.449; ML:0.843-0.898; GL: 1.15-1.33; CI: 94.08-99.41; SI: 87.48-94.13.

Head: brownish-yellow, darker toward apex around three prominent ocelli; head oval-shaped, longer than broad, becoming narrower toward apex; eyes large, breaking outline of head in full frontal view; 12 segmented antennae; scapes surpass posterior margin by about length of first 2 funicular segments; clypeus broad, slightly convex medially, with erect hairs scattered throughout; shape of anterior clypeal margin similar to that of worker, but median point less defined; mandible broad with 4 teeth; basal tooth enlarged and rectangular, apically truncated, as in worker. Mesosoma: yellow; pronotum short and collar-like, overarched by mesonotum; mesonotum rounded anteriorly; dorsum flat with erect hairs scattered throughout, especially on scutellum; propodeum and declivity difficult to distinguish from each other. Gaster: yellow; covered in a layer of appressed hairs, with scattered erect hairs throughout. Genitalia: in lateral view, parameres thin, tapering to rounded apices; lateral surface covered in layer of appressed hairs that are shorter and thicker toward base, becoming longer and sparser toward tip; in dorsal view parameres give genitalia a roughly triangular appearance; cuspi short, sharply bent toward digiti, with peg-like teeth at apex; digiti longer than cuspi and straight with rounded apex; peg-like teeth at about mid-length of digiti where cuspi meet.

Type Material
LaPolla (2004):

Acropyga (Atopodon) butteli Forel, 1912c: 772 (q.). Holotype queen, MALAYSIA: Selangor (von Buttel-Reepen) (not in MNNG) [not examined].

Acropyga (Atopodon) termitobia Forel, 1912c: 773 (q.). Holotype queen, MALAYSIA: Selangor (von Buttel-Reepen) (not in MNNG) [not examined]. NEW SYNONYM.

Acropyga (Atopodon) amblyops Forel, 1915a: 34 (w.). 2 syntype workers, INDONESIA: Sumatra, Sinabang Simalur [?], (E. Jacobson) (MHNG) [examined]. NEW SYNONYM.

''Atopodon meermohri Stärcke, 1930: 375 (w.). Syntype worker(s?), INDONESIA: Palau Island (depository unknown) [not examined]. NEW SYNONYM.

Acropyga (Atopodon) distinguenda Karavaiev, 1935: 110 (w.q.m.). Syntype worker(s?), syntype queen(s?), syntype male(s?), VIETNAM (depository unknown) [not examined]. NEW SYNONYM.

Acropyga (Atopodon) baodaoensis Terayama, 1985: 284 (w.q.m.). Holotype worker, TAIWAN: Nanshanchi, Nanfen Cun, Ren'ai Xiang, Nantou Hsien (M. Terayama) [not examined]; 5 paratype workers, 1 paratype queen, locality the same as holotype (BMNH) (BPBM) [examined]. NEW SYNONYM.

References based on Global Ant Biodiversity Informatics

 * CSIRO Collection
 * 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. 1912. Descriptions provisoires de genres, sous-genres, et espèces de Formicides des Indes orientales. Revue Suisse de Zoologie 20: 761-774.
 * Forel A. 1915. Fauna Simalurensis. Hymenoptera Aculeata, Fam. Formicidae. Tijdschr. Entomol. 58: 22-43.
 * Guénard B., and R. R. Dunn. 2012. A checklist of the ants of China. Zootaxa 3558: 1-77.
 * Jaitrong W., B. Guenard, E. P. Economo, N. Buddhakala, and S. Yamane. 2016. A checklist of known ant species of Laos (Hymenoptera: Formicidae). Asian Myrmecology 8: 1-32. DOI: 10.20362/am.008019
 * Karavaiev V. 1935. Neue Ameisen aus dem Indo-Australischen Gebiet, nebst Revision einiger Formen. Treubia 15: 57-118.
 * LaPolla J.S. 2004. Acropyga (Hymenoptera: Formicidae) of the world. Contributions of the American Entomological Institute 33(3): 1-130.
 * Li Z.h. 2006. List of Chinese Insects. Volume 4. Sun Yat-sen University Press
 * Ogata K. 2005. Asian ant inventory and international networks. Report on Insect inventory Project in Tropic Asia TAIIV: 145-170.
 * Ohasi M., Y. Maekawa, Y. Hashimoto, Y. Takematsu, S. Hasin, and S. Yamane. 2017. CO2 emission from subterranean nests of ants and termites in a tropical rain forest in Sarawak, Malaysia. Applied Soil Ecology 117–118: 147–155.
 * 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
 * Ran H., and S. Y. Zhou. 2011. Checklist of Chinese Ants: the Formicomorph Subfamilies (Hymenoptera: Formicidae) (I). Journal of Guangxi Normal University: Natural Science Edition. 29(3): 65-73.
 * Terayama M. 1985. Two new species of the genus Acropyga (Hymenoptera, Formicidae) from Taiwan and Japan. Kontyû 53: 284-289.
 * Terayama M. 2009. A synopsis of the family Formicidae of Taiwan (Insecta: Hymenoptera). Research Bulletin of Kanto Gakuen University. Liberal Arts 17:81-266.
 * Terayama M.; Fellowes, J. R.; Zhou, S. 2002. The East Asian species of the ant genus Acropyga Roger, 1862 (Hymenoptera: Formicidae: Formicinae). Edaphologia 70:21-32.
 * Terayama Mamoru. 2009. A synopsis of the family Formicidae of Taiwan (Insecta, Hymenoptera). The Research Bulletin of Kanto Gakuen University 17: 81-266.
 * Terayama, M. 2009. A synopsis of the family Formicidae of Taiwan (Insecta; Hymenoptera). The Research Bulletin of Kanto Gakuen University 17: 81-266.
 * Terayama. M. and Inoue. N. 1988. Ants collected by the members of the Soil Zoological Expedition to Taiwan. ARI Reports of the Myrmecologists Society (Japan) 18: 25-28