Strumigenys didyma

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

The type material was collected from a riverine forest litter sample.

Identification

Bolton (2000) - A member of the arnoldi complex in the Strumigenys arnoldi-group. Unique in the Afrotropical arnoldi-group because of its sculptured pleurae; in all other species of the group these sclerites are mostly to entirely smooth.

Keys including this Species

Key to Afrotropical Strumigenys

Distribution

Latitudinal Distribution Pattern

Latitudinal Range: -4.151388889° to -4.15972°.


North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

Source: AntMaps

Distribution based on Regional Taxon Lists

Afrotropical Region: United Republic of Tanzania.

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.

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Castes

Nomenclature

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

didyma. Strumigenys didyma Bolton, 2000: 592 (w.) TANZANIA.

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 2.2, HL 0.61, HW 0.43, CI 70, ML 0.21, MI 34, SL 0.34, SI 79, PW 0.27, AL 0.60. Characters of arnoldi-complex. Mandible gradually increasing in width from proximal preapical tooth to base; outer margin shallowly convex and obviously inflected near base. Left proximal preapical tooth broken off short in holotype; left distal preapical tooth not reduced to a denticle, about same size as right distal. Distal preapical tooth on right mandible about half the length of the spiniform proximal. Scape weakly flattened, broadest at about the midlength; its leading edge moderately convex but not strongly expanded. Cephalic dorsum with a transverse row of 4 remiform standing hairs close to occipital margin, and with a similar pair close to highest point of vertex. Pronotal humeral hair flagellate; side of pronotum with sculpture present. Mesopleuron, metapleuron and side of propodeum finely reticulate or reticulate-shagreenate to superficially reticulate-punctate, smooth only near propodeal spiracle. Disc of postpetiole superficially reticulate-punctate. Dorsum of first gastral tergite with fine superficial sculpture from apices of basigastral costulae to apex of sclerite. Hairs on first gastral tergite stoutly remiform.

Type Material

Holotype worker, Tanzania: above Kisiwani on Nakombo River, 4°09'35"S, 37°56'29"E, 29.xi.1995, Winkler bag extraction ex litter in riverine forest, SAM-HYM-C009833 (H. G. Robertson) (South African Museum).

References

Bolton, B. 2000. The ant tribe Dacetini. Memoirs of the American Entomological Institute. 65:1-1028. (page 592, worker described)

References based on Global Ant Biodiversity Informatics

IZIKO South Africa Museum Collection