Strumigenys incomposita

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

Nothing is known about the biology of Strumigenys incomposita.

Identification

Bolton (2000) - A member of the ebbae complex in the Strumigenys koningsbergeri-group. Closest related to Strumigenys kakothema, but the latter is smaller, lacks longitudinal rugulae on the vertex and has a slightly longer preapical tooth. The two together are characterised within the ebbae-complex by their well-developed preocular impressions, denser than usual pilosity and convex inner mandibular margins. Although neither incomposita nor kakothema has a conspicuous lamella on the inner mandibular margin, both appear to be in process of developing one and can be described as incipiently lamellate. The margin, apart from being convex in full-face view, is sharp-edged and prominent, differentiated from the remainder of the mandible blade, although only weakly so.

Keys including this Species

• Key to Strumigenys of East Asia

Distribution

Distribution based on Regional Taxon Lists

Indo-Australian Region: Indonesia (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

Expand 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. ‎

Nomenclature

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

• incomposita. Strumigenys incomposita Bolton, 2000: 844, fig. 451 (w.) INDONESIA (Sumatra).

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 2.6, HL 0.76, HW 0.63, CI 83, ML 0.33, MI 43, SL 0.38, SI 60, PW 0.33, AL 0.69. With characters of ebbae-complex. Preapical tooth short-conical and very weakly recurved, its length distinctly less than half width of mandible at point where it arises; preapical tooth located at about midlength of narrowed apical section of mandible. Inner margin of mandible shallowly convex proximal of preapical tooth, sharp-edged but without a prominent translucent lamella. Outer margin of mandible straight from basal inflection to apicodorsal tooth. Preocular concavity in ventrolateral margin of head broad and shallow. Upper scrobe margins evenly divergent from frontal lobes posteriorly; outer arc of eye visible in full-face view. Vertex with longitudinal fine rugulae that diverge posteriorly, becoming weakly reticulate on occipital lobes. Dorsum of head in profile with short erect hairs along occipital margin and n u merous erect hairs anterior to this; anteriormost pair at about level of eye, well in front of highest point of vertex. Pronotum with two pairs of short standing hairs, located anterodorsally. Mesonotum with a single pair of short erect hairs. Katepistemum smooth, metapleuron with a smooth patch. Bullae of femoral glands present but inconspicuous on middle and hind legs. Lamella on propodeal declivity with posterior (free) margin shallowly concave; propodeal teeth very short. Disc of postpetiole smooth. Standing hairs on first gastral tergite simple.

Paratype. TL 2.6, HL 0.75, HW 0.62, CI 83, ML 0.32, MI 43, SL 0.38, SI 61, PW 0.33, AL 0.70.

Type Material

Holotype worker, Indonesia: Sumatra, Jambi, Mt Kerinci, 1750-1850 m., 11-12.xi.1989, #11 (Agosti, Lobl & Burckhardt) (Musee d'Histoire Naturelle Genève). Paratype. 1 worker with same data as holotype (The Natural History Museum).

References

• Bolton, B. 2000. The ant tribe Dacetini. Memoirs of the American Entomological Institute. 65:1-1028. (page 844, figs. 451 worker described)
• Musfira, S.H., Rafi, M., Gusti, M., Putri, D.H., Satria, R. 2022. New data on the genus Strumigenys (Hymenoptera: Formicidae) from Sumatra. Zoosystematica Rossica 31(1): 74–86 (doi:10.31610/zsr/2022.31.1.74).

References based on Global Ant Biodiversity Informatics

• Bolton B. 2000. The ant tribe Dacetini. Memoirs of the American Entomological Institute 65: 1-1028.