Strumigenys inopinata

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Strumigenys inopinata
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Strumigenys
Species: S. inopinata
Binomial name
Strumigenys inopinata
(De Andrade, 1994)

Strumigenys inopinata casent0911230 p 1 high.jpg

Strumigenys inopinata casent0911230 d 1 high.jpg

Specimen Labels

Nothing is known about the biology of Strumigenys inopinata.


Baroni Urbani & De Andrade (1994) - A small Rhopalothrix (=Strumigenys) species characterised by the following combination of characters: body virtually hairless except on the appendages, six antennal joints, mandibles with an apical fork composed of one apical tooth and a row of seven denticles distally increasing in size.


Distribution based on Regional Taxon Lists

Oriental Region: Sri Lanka (type locality).

Distribution based on AntMaps


Distribution based on AntWeb specimens

Check data from AntWeb




The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.

  • inopinata. Rhopalothrix inopinata De Andrade, in Baroni Urbani & De Andrade, 1994: 54, figs. 31, 32 (w.) SRI LANKA. Combination in Strumigenys: Baroni Urbani & De Andrade, 2007: 121; in Pyramica (unpublished). Combination in Strumigenys: Baroni Urbani & De Andrade, 2007: 121

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



TL 1.86; HL 0.48; HW 0.48; ML 0.20; SL 0.20; AL 0.50; petiole maximum length 0.24; petiolar node maximum width 0.16; postpetiole maximum length 0.16; postpetiole maximum width, 0.28. CI 100; MI 35.7; SI 41.7.

Head as broad as long, with feebly excised posterior border and sides projecting posteriorly to the antenna scrobes. Clypeus triangular, reaching the genae laterally and with nearly straight anterior border. Median sulcus evident. Eyes absent. Mandibles with straight external borders; masticatory border armed with four distal, medium-size denticles followed by an apical acuminate tooth and a set of denticles forming an apical fork as described in the diagnosis. Labrum broad posteriorly, anteriorly bilobed and projecting as to fill the intramandibular gap. Scapes as long as the mandibles, strongly bent at the base. Funiculi 5-segmented, resulting so from the fusion of antennal joints V + VI, as indicated by a set of equally long hairs in a row, like those present on the distal border of each joint and still recognizable at mid-length of actual joint V. Last funicular joint longer than the sum of the remaining ones.

Trunk slightly longer than the cephalic capsule. Pronotum and propodeum convex in side view; promesonotal suture highly visible, mesonotal dorsum lower than the propodeal dorsum and propodeal suture barely visible on the sides. Propodeum with superior face slightly marginate on each side by a carina followed by a denticle; its descending face concave and equally marginate on each side by a low lamelliform carina.

Peduncle of the petiole short and dorsolaterally marginate by a carina; petiolar node as broad as the length of the postpetiole. Postpetiole posteriorly as broad as the anterior face of the gaster and articulated to it over its whole width. Spongiform processes on posteriolateral sides of the petiole, posterior dorsum of postpetiole and anterior face of the gaster poorly developed. Ventrolateral sides of the postpetiole with well developed spongiform processes.

Gaster oval in dorsal view and with protruding sting.

Sculpture: dorsum of the head covered with deep foveae, less deep on the posterior half of the clypeus and completely missing on its central and anterior parts. A similar structure, more superficial and organized in longitudinal ridges on the dorsum of the trunk and on the sides of the pronotum; mesopleurae and propodeal sides only very lightly sculptured. Scapes and legs with foveae smaller and thicker than those on dorsum; basal portion of the mandibles with the foveae irregular and spaced; distal part of the mandibles and funiculus simply punctate. Petiole and gaster shining and slightly punctate. Anterior third of the first gastral tergite costulate.

Colour: light brown.

Pilosity: dorsum of the head and trunk with extremely rare and minute ( < 0.01 mm long), at least partly clavate hairs arising from the centre of a few foveae. Mandibles, dorsal surface of scapes, funiculus, tibiae and tarsi with pointed decumbent hairs ca. 0.02 mm long. One single plumate hair over the anterior edge of the angular part of the scape. Similar, longer and appressed hairs on the last two funicular joints, on the internal border of the tibiae and around the apical fork of the mandibles.

Type Material

Holotype: worker (unique with postpetiole and gaster detached but glued on the same triangular support), Central Ceylon, Kandy, 600 m, Mussard Besuchet Loblleg., deposited in the Musee d' Histoire Naturelle, Geneva.


From the Latin inopinatus (=unexpected).


  • 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.