Strumigenys theia

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Strumigenys theia
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Strumigenys
Species: S. theia
Binomial name
Strumigenys theia
(Bolton, 2000)

Pyramica theia casent0102605 profile 1.jpg

Pyramica theia casent0102605 dorsal 1.jpg

Specimen labels

Nothing is known about the biology of Strumigenys theia.


Bolton (2000) - A member of the Strumigenys capitata-group. Members of the group in which the apicoscrobal and pronotal humeral hairs are uniformly stout and usually remiform or clavate (never flagellate) include the small to minute species Strumigenys charybdis, Strumigenys phasma, Strumigenys tethys and Strumigenys themis, and the distinctly larger species Strumigenys capitata, Strumigenys pedunculata and Strumigenys theia. In the smaller species of the first complex (HW 0.39-0.50) the postpetiole disc is usually smooth and shining, or at most with vestigial sculpture. The larger species of the second complex (HW 0.50-0.62) all have the postpetiole disc longitudinally costulate. Of the three theia is easily diagnosed as it has 3 (rarely 4) pairs of stout erect mesonotal hairs, and has the entire side of the alitrunk densely and sharply reticulate-punctate. In contrast both capitata and pedunculata have 2 pairs of standing mesonotal hairs and have most or all of the mesopleuron smooth and highly polished.

Keys including this Species


Distribution based on Regional Taxon Lists

Indo-Australian Region: Borneo (type locality), Indonesia, Malaysia, Philippines.

Distribution based on AntMaps


Distribution based on AntWeb specimens

Check data from AntWeb




The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

  • theia. Pyramica theia Bolton, 2000: 407 (w.) BORNEO. Combination in Strumigenys: Baroni Urbani & De Andrade, 2007: 129

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.



Holotype. TL 3.0, HL 0.72, HW 0.61, CI 85, ML 0.17, MI 24, SL 0.35, SI 57, PW 0.44, AL 0.86. Basal lamella clearly visible even when mandibles fully closed. Apicoscrobal hair stout, remiform to weakly and gradually clavate apically. Cephalic dorsum with a pair of standing hairs just in front of highest point of vertex and with a transverse row of 4 similar hairs close to the occipital margin. Reticulate-punctate sculpture of head sharply defined, the dorsum with conspicuous short appressed spatulate ground pilosity. Eye with 6 ommatidia in the longest row. Dorsal alitrunk sculptured as the head. Pronotal humeral hair stout and remiform. With alitrunk in profile the entirety of the side blanketed with dense, sharply defined, reticulate-punctate sculpture; the mesopleuron without a smooth shining area. Mesonotum with 3 pairs of stout standing hairs that are remiform to clavate. Similar hairs present dorsally on petiole node (2 pairs), disc of postpetiole (3 pairs) and first gastral tergite (4 transverse rows with 3-5 hairs in each row). Petiole node in dorsal view densely reticulate-punctate, fractionally broader than long. Postpetiole disc finely and densely, but very sharply and conspicuously, longitudinally costulate.

Paratypes. TL 2.9- 3.0, HL 0.68-0.72, HW 0.59-0.62, CI 85-89, ML 0.17-0.18, MI 24-25, SL 0.34-0.36, SI 56-59, PW 0.42-0.45, AL 0.84-0.88 (7 measured). As holotype but eye with 5-6 ommatidia in the longest row. Most paratypes with same mesonotal pilosity as holotype but one with a fourth pair of shorter and finer standing hairs among the three stouter, longer pairs. Petiole node in dorsal view varies from about as broad as long to very slightly broader than long. Fine punctulae may be present on the postpetiole between the costulae. This is not obvious in the holotype but is more distinct in some of the paratypes.

Type Material

Holotype worker, Malaysia: Sabah, Crocker Range, 1350 m., 17.v.1987, no. 28a (Burckhardt & Lobl) (Musee d'Histoire Naturelle Genève).

Paratypes. 5 workers with same data as holotype. 2 workers with same data but 19.v.1987, no. 31a (MHNG, The Natural History Museum, Museum of Comparative Zoology).


  • Baroni Urbani, C. & De Andrade, M.L. 2007. The ant tribe Dacetini: limits and constituent genera, with descriptions of new species. Annali del Museo Civico di Storia Naturale “G. Doria” 99:1-191.
  • Bolton, B. 2000. The ant tribe Dacetini. Memoirs of the American Entomological Institute. 65:1-1028. (page 407, worker described)

References based on Global Ant Biodiversity Informatics

  • Hashimoto Y., and M. Mohamed. 2004. A preliminary survey of ant fauna at Crocker Range Park. In: Maryati Mohamed, Zulhazman Hamzah, T. Tachi & J. Nais (eds.). Crocker Range scientific expedition 2002. Kota Kinabalu: Universiti Malaysia Sabah, pp. 51-71.
  • 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