Strumigenys doxa

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

This rarely collected species is known from montane forest and "dense forest". Collections have been made from litter samples and and a rotten tree stump.

Identification

Bolton (2000) - A member of the diux complex in the Strumigenys scotti-group. S. doxa is easily distinguished from Strumigenys diux, the only other species in the complex, by having the pronotum with numerous standing remiform hairs in addition to those at the humeral angles. Also, the cephalic dorsolateral margin posteriorly has 2 or more stiff erect hairs that are longer than hairs on leading edge of scape, see also under diux.

Keys including this Species

• Key to Malagasy Strumigenys

Distribution

Distribution based on Regional Taxon Lists

Malagasy Region: Madagascar (type locality).

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.

Biology

Explore Overview of Strumigenys biology  Strumigenys were once thought to be rare. The development and increased use of litter sampling methods has led to the discovery of a tremendous diversity of species. Many species are specialized predators (e.g. see Strumigenys membranifera and Strumigenys louisianae). Collembola (springtails) and other tiny soil arthropods are typically favored prey. Species with long linear mandibles employ trap-jaws to sieze their stalked prey (see Dacetine trap-jaws). Larvae feed directly on insect prey brought to them by workers. Trophallaxis is rarely practiced. Most species live in the soil, leaf litter, decaying wood or opportunistically move into inhabitable cavities on or under the soil. Colonies are small, typically less than 100 individuals but in some species many hundreds. Moist warm habitats and micro-habitats are preferred. A few better known tramp and otherwise widely ranging species tolerate drier conditions. Foraging is often in the leaf litter and humus. Workers of many species rarely venture above ground or into exposed, open areas. Individuals are typically small, slow moving and cryptic in coloration. When disturbed individuals freeze and remain motionless. Males are not known for a large majority of species. ‎

Castes

Images from AntWeb

Holotype of Strumigenys doxa. Worker. Specimen code casent0005527. Photographer April Nobile, uploaded by California Academy of Sciences.	Owned by MCZ, Cambridge, MA, USA.

Nomenclature

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

• doxa. Strumigenys doxa Fisher, in Bolton, 2000: 678, fig. 401 (w.q.) MADAGASCAR.

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

Description

Worker

Holotype. TL 3.3, HL 0.83, H W 0.66, CI 80, ML 0.34, MI 41, SL 0.43, SI 66, PW 0.40, AL 0.92. Characters of diux-complex. Mandibles in full-face view with outer margins shallowly and evenly convex, the width gradually decreasing from near the base to the apicodorsal tooth. Upper scrobe margin evenly and shallowly convex in full-face view, not bordered by a rim or flange, the eyes visible and 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, with 6-7 ommatidia in longest row. Scape short and stout, shallowly and gently curved; hairs on leading edge narrow, flattened or spoon-shaped apically. Cephalic dorsum densely clothed with curved narrow spatulate to spoon-shaped ground-pilosity, the upper scrobe margin fringed with hairs which are the same shape and size as those on the dorsum. Posterior third of cephalic dorsum with standing remiform hairs arranged in transverse rows; dorsolateral margin of occipital lobe with projecting hairs, the anteriormost in apicoscrobal position. Pronotal humeral hair stiffly filiform and thickened apically. Promesonotum with numerous standing stiff remiform hairs. Propodeum with a pair of short, fine, posteriorly curved hairs immediately anterior of propodeal spines. Dorsal alitrunk with ground-pilosity as on head, concentrated on anterior portion of pronotum. Dorsum of alitrunk in outline convex anteriorly and more or less flat posteriorly; posterior portion of mesonotum only slightly depressed below the anterior margin of propodeum. Anterior mesonotum with a narrow carina above the mesothoracic spiracle. Propodeal tooth broadly triangular and pointed apically, declivity without a distinct lamella. Alitrunk dorsum, petiole, and postpetiole densely reticulate-punctate. Sides of pronotum with punctate sculpture dorsally, remainder smooth. Pleurae and sides of propodeum mostly smooth and shiny except for peripheral fine punctures. Petiole in profile with a straight ventral spongiform strip that is similar in width to antennal scape; ventral spongiform lobe of postpetiole slightly larger than the exposed area of the postpetiole disc in profile. Basigastral costulae short and widely spaced, but sharply defined. Dorsal surfaces of petiole, postpetiole and gaster with standing remiform hairs. Colour medium to dark brown.

Measurements of this material extend the range shown by the type-series: HL 0.83, HW 0.63, CI 76, ML 0.35, MI 42, SL 0.47, SI 74.

Type Material

Holotype worker, Madagascar: 11.0 km. WSW Befingotra, Res. Anjanaharibe-Sud, 14°45'S, 49°27'E, 1565 m., 16.xi.1994, sifted litter (leaf mold rotten wood), montane rainforest #1232 (17)-6 (B. L. Fisher) (Museum of Comparative Zoology).

Paratype. 1 queen (dealate) with same data as holotype but 1550 m., 18.xi.1994, ex rotting tree stump, montane rainforest #1240-1 (South African Museum).

References

• 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 678, 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.