Tetramorium densopilosum

Tetramorium densopilosum
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Crematogastrini
Genus: Tetramorium
Species: T. densopilosum
Binomial name
Tetramorium densopilosum
Radchenko & Arakelian, 1990

Nothing is known about the biology of Tetramorium densopilosum.


Csösz and Schulz (2010) - A member of the Tetramorium ferox species complex in the Tetramorium caespitum species group. The very dense pubescence on the first gastral tergite makes the T. densopilosum gynes unique within this group.

Tetramorium densopilosum workers cannot be confused with those of Tetramorium diomedeum or Tetramorium aegeum. The general appearance of the head and mesosoma of T. densopilosum workers is always rugulose and microreticulate, but head and mesosoma of the two latter species are always shiny and usually at least partly smooth. Tetramorium feroxoides workers usually bear feeble, often parallel rugulae on head and mesosoma.

Separation of T. densopilosum and Tetramorium ferox workers is very difficult. With 8 observed workers we are not able to show variation in T. densopilosum. Tetramorium densopilosum workers have a slightly trapezoidal head and the petiolar node is slightly angulate anterodorsally in contrast to that of T. ferox, which is rounded. The frontal carinae are more developed in T. densopilosum, and also the erect hairs of mesosoma seem to be longer end denser than those of T. ferox. A discriminant D(4b) function proves the separation between T. ferox and T. densopilosum: see differential diagnosis of T. ferox.

A discriminant function using various morphological measurements has also been defined and can be used to make determinations in this species group.

Keys including this Species


Distribution based on Regional Taxon Lists

Palaearctic Region: Armenia (type locality), Georgia, Russian Federation, Turkey.

Distribution based on AntMaps

Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.




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

  • densopilosum. Tetramorium densopilosus Radchenko & Arakelian, 1990: 372, fig. 1 (w.q.m.) ARMENIA. See also: Csösz & Schulz, 2010: 15.

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



Csösz and Schulz (2010) - Medium to large size, CS 833 [763, 878]. Whole body and appendages light brown to brown. Head slightly longer than broad, CL/CW 1.04 [1.02, 1.05], with straight sides, straight posterior head margin and rounded corners. Eyes small, EYE 0.17 [0.17, 0.18]. Frons moderately wide, FR/CS 0.40 [0.38, 0.41], frontal lobes usually as wide as the frons, rarely slightly broader, FL/FR 1.00 [1.00, 1.02]. Scape long, SL/CS 0.78 [0.76, 0.80], with a feeble dorsal carina basally. Promesonotal dorsum slightly convex, metanotal groove moderately deep. Propodeal denticles moderately long. Petiolar node very high, NOH/NOL 1.23 [1.06, 1.44] trapezoid seen in profile, steeply rounded backward.

Head longitudinally rugulose and microreticulate, posterior surface ruguloso-reticulate, ground surface microreticulate, appears dull. Mesosoma dorsum and mesopleura ruguloso-reticulate, ground surface coarsely microreticulate. Dorsum of petiolar node ruguloso-reticulate, ground surface microreticulate, median part smooth. Dorsum of postpetiole rugulose and microreticulate. First gastral tergite smooth, appears shiny. Ventral surface of head with a row of short setae only (without long C-shape hairs).


Csösz and Schulz (2010) - Medium to large size, CS 980 [970, 990]. Head, mesosoma and appendages light brown, gaster dark brown. Head broader than long, CL/CW 0.87 [0.83, 0.90] with sides and posterior margin straight. Head trapezoid in full face view, narrower at genae. Frons moderately wide, FR/CS 0.40 [0.38, 0.41]. Scape long, SL/CS 0.76 [0.74, 0.78], without a dorsal carina basally, its surface is smooth and shiny. Head slightly narrower than scutum, MW/CS 1.06 [1.05, 1.07]. Propodeal teeth long and acute. Petiole and postpetiole wide, CS/PEW 1.71 [1.68, 1.75], CS/PPW 1.28 [1.24, 1.33].

Head dorsum, posterior surface and sides ruguloso-reticulate, ground surface microreticulate. Frons longitudinally rugulose and microreticulate. Scutum and scutellum longitudinally rugulose. Sides of mesosoma, rugoso-reticulate and microreticulate, ventral part of katepisternum always rugulose, or microreticulate. Dorsum of petiolar node and postpetiole coarsely reticulate and microreticulate, medially shiny. First gastral tergite smooth, appears shiny, 1st gastral tergite very densely covered by pubescent hairs. Ventral surface of head with a row of short setae only (without long C-shape hairs).


Csösz and Schulz (2010) - Head sides feebly convex, posterior margin and corners rounded. Scutum much broader than head. Propodeal denticles short but acute, propodeum angulate in profile. Dorsum of petiolar with a transverse crest, dorsolaterally sharp and angulate. Whole body and appendages brownish black. Head, scutum, scutellum, anepi- and katepisternum as well as petiole and postpetiole finely rugulo-reticulate, between main sculpturation microreticulate. First gastral tergite smooth, appears shiny, 1st gastral tergite very densely covered by pubescent hairs.

Type Material

Csösz and Schulz (2010) - Holotype queen and paratype worker, male (6w, 4m): Armenia, Nature Reserve, 14.VI.1986 (A. Radchenko) [label: Arm SSR Khosrovskij, z-k No 237.86, A.Radchenko 14.6.86] (examined) Institute of Zoology of the Ukranian National Academy of Sciences.


References based on Global Ant Biodiversity Informatics

  • Borowiec L. 2014. Catalogue of ants of Europe, the Mediterranean Basin and adjacent regions (Hymenoptera: Formicidae). Genus (Wroclaw) 25(1-2): 1-340.
  • Csősz S., and A. Schulz. 2010. A taxonomic review of the Palaearctic Tetramorium ferox species-complex (Hymenoptera, Formicidae). Zootaxa 2401: 1-29.
  • Dubovikoff D. A., and Z. M. Yusupov. 2018. Family Formicidae - Ants. In Belokobylskij S. A. and A. S. Lelej: Annotated catalogue of the Hymenoptera of Russia. Proceedingss of the Zoological Institute of the Russian Academy of Sciences 6: 197-210.