Strumigenys inatos

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

Strumigenys inatos casent0005556 profile 1.jpg

Strumigenys inatos casent0005556 dorsal 1.jpg

Specimen labels

Relatively well collected for a Strumigenys species, S. inatos is known from a range of forest habitats. Samples have been taken from rotten logs, sticks, litter and a ground nest.


Bolton (2000) - A member of the scotti complex in the Strumigenys scotti-group. As with many of the paratype specimens, non-type specimens lacked a stiff erect apicoscrobal hair. These samples differ in two aspects from the type material. The specimens from Andronobe and Cap Masoala have erect hairs on mesonotum, petiole, postpetiole and gaster that are distinctly remiform to clavate. In contrast, type-material and other nonparatypic workers had filiform to narrowly clavate hairs. Workers and queens from Ivohihe, were slightly larger than other workers and queens from other localities examined. Perhaps new collections will eventually demonstrate that this widespread species includes distinct localized species, but for the present, I consider it best to regard them as a single species.

Of the scotti-complex species having the dorsum of petiole node reticulate-punctate inatos is distinguished by having: 1 Mesonotum with only a single pair of erect hairs, located at anterior margin. 2 Ventral spongiform tissue of petiolar peduncle in profile an irregular, narrow strip along the base of the peduncle, its deepest point less than maximum width of eye. 3 Postpetiole disc not entirely smooth and shiny; disc longitudinally striolate and usually feebly punctate on lateral margins. 4 Anterior half of fist gastral sternite without hairs.

See under Strumigenys glycon for further discussion.

Keys including this Species


Distribution based on Regional Taxon Lists

Malagasy Region: Madagascar (type locality).

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.

  • inatos. Strumigenys inatos Fisher, in Bolton, 2000: 684 (w.q.) MADAGASCAR.

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



Holotype. TL 2.3, HL 0.55, HW 0.43, CI 79, ML 0.28, MI 52, SL 0.37, SI 85, PW 0.26, AL 0.60. Characters of scotti-complex. Mandibles in full-face view with outer margins very shallowly and evenly convex, the width of the basal half approximately constant except near the base. Upper scrobe margin evenly and shallowly convex in full face view, not bordered by a rim or flange, the eyes visible, the apices of the upper scrobe margins confluent with the sides of the occipital lobes through an even curve, without an angle separating the two. Maximum diameter of eye slightly greater than maximum width of scape, 4-5 ommatidia in longest row. Scape narrow and subcylindrical, curved near the base; hairs on leading edge slender, slightly flattened or narrowly spatulate apically. Cephalic dorsum clothed with curved narrow spatulate to spoon-shaped ground-pilosity, the upper scrobe margin fringed with hairs which are similar in shape and size as those on the dorsum. Cephalic dorsum with 6 standing narrow filiform hairs arranged in a transverse row of 4 close to the occipital margin and a more anteriorly situated pair. In addition a short erect apicoscrobal hair is present in the holotype and in some of the paratypes. Pronotal humeral hair flagellate. Anterior margin of mesonotum with a pair of standing remiform to clavate hairs. Propodeum with one pair of short, fine, posteriorly curved hairs immediately anterior of propodeal spines. Dorsal alitrunk with sparse ground-pilosity that is similar in size and shape as on cephalic dorsum. Dorsum of alitrunk in outline convex anteriorly and posteriorly gently sloping to the declivity. Metanotal groove shallowly impressed. Anterior mesonotum with a thin carina above the mesothoracic spiracle; mesopleural gland set in a small circular notch. Propodeal tooth triangular, pointed apically and subtended by an inconspicuous, very narrow lamella. Pronotal dorsum longitudinally feebly striolate-rugulose and punctate with a longitudinal carina along dorsal midline. Remainder of dorsal alitrunk reticulate-punctate. Sides of pronotum longitudinally feebly striolate. Pleurae and sides of propodeum smooth, punctate peripherally. Postpetiole disc longitudinally striolate and feebly punctate on lateral margins. In profile ventral spongiform tissue of petiolar peduncle an irregular, narrow strip along the base of the peduncle, at deepest less than maximum width of eye. Ventral spongiform tissue of postpetiole moderately developed. Basigastral costulae sharply defined, radiating on each side of a broad central clear area. Dorsal surface of petiole, postpetiole and gaster with standing filiform to remiform hairs. Colour light brown.

Paratypes. TL 2.2-2.5, HL 0.53-0.62, HW 0.40-0.45, CI 70-78, ML 0.27-0.30, MI 44-51, SL 0.34-0.38, SI 78-89, PW 0.26-0.29, AL 0.58-0.64 (8 measured). Most of the paratype material did not have a standing hair located near the apex of the upper scrobe margin, otherwise the paratype material matched the holotype

Measurements of this material extend the range shown by the type-series: HL 0.55-0.70, HW 0.40-0.53, ML 0.27-0.35, MI 48-52, SL 0.36-0.45, SI 79-95 (25 measured).

Type Material

Holotype worker, Madagascar: 9.2 km. WSW Betingotra, Res. Anjanaharibe-Sud, 14°45'S, 49°28'E, 1200 m., 9.xi.1994, sifted litter (leaf mold rotten wood), montane rainforest #1192 (36)-8 (B. L. Fisher) (Museum of Comparative Zoology).

Paratypes. 8 workers and 1 queen (deal ate) with same data as holotype but coded (2)-7, (10)-10, (13)-6, (29)-6, (9)-9, (25)-5, (40)-6, (41)-6 (The Natural History Museum, South African Museum).


  • Fisher, B.L. 2000. The Malagasy fauna of Strumigenys. Pp. 612-696 in: Bolton, B. 2000. The ant tribe Dacetini. Memoirs of the American Entomological Institute. 65:1-1028. (page 684, worker described)

References based on Global Ant Biodiversity Informatics

  • Bolton, B. 2000. The Ant Tribe Dacetini. Memoirs of the American Entomological Institute 65
  • Fisher B. L. 2003. Formicidae, ants. Pp. 811-819 in: Goodman, S. M.; Benstead, J. P. (eds.) 2003. The natural history of Madagascar. Chicago: University of Chicago Press, xxi + 1709 pp.
  • Fisher, B. 2002. Ant diversity patterns along an elevational gradient in the Reserve Speciale de Manongarivo, Madagascar. in Gautier, L. and S.M. Goodman, editors, Inventaire Florestique et Faunistique de la Reserve Speciale de Manongarivo (NW Madagascar)
  • Goodman S., Y. Anbdou, Y. Andriamiarantsoa, B. L. Fisher, O. Griffiths, B. Keitt, J. J. Rafanomezantsoa, E. Rajoelison, J. C. Rakotonirina, L. Ranaivoarisoa et al. 2017. Results of a biological inventory of the Nosy Ankao island group, Parc National de Loky-Manambato, northeastern Madagascar. Malagasy Nature, Association Vahatra, 2017, 11, <>