Strumigenys diaptyxis

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

The small number of collections of this species are all from wet forest habitat. The holotype, a lone worker from the Penas Blancas Valley, was collected at night from low vegetation in mature wet forest.

Identification

Bolton (2000) - A member of the Strumigenys emeryi-group. The lack of mesonotal flagellate hairs, reduction of propodeal lamella together with presence of propodeal lacuna, deep ventral spongiform curtain on petiole and form of sculpture combine to make this species easily recognisable.

Longino (Ants of Costa Rica) - Apical fork of mandible with one intercalary tooth; mandible with small preapical tooth very close to apical fork, and a minute denticle near the apical third of mandible length; gaster smooth and shining, with setae stiff, straight, slightly thickened.

This species shares characters with both Strumigenys micretes and Strumigenys nevermanni. It is intermediate in size between micretes and nevermanni. It has gastral pilosity more like nevermanni than micretes. It has a uniformly punctate face, in contrast to the other two species which have more rugose faces.

Keys including this Species

• Key to Neotropical and Nearctic Strumigenys

Distribution

Latitudinal Distribution Pattern

Latitudinal Range: 10.317° to 10.317°.

North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

• Source: AntMaps

Distribution based on Regional Taxon Lists

Neotropical Region: Costa Rica (type locality), Nicaragua.

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

Worker. Specimen code jtlc000004299. Photographer D. J. Cox, uploaded by California Academy of Sciences.	Owned by JTLC.

Nomenclature

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

• diaptyxis. Strumigenys diaptyxis Bolton, 2000: 513 (w.) COSTA RICA.

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 2.8, HL 0.70, HW 0.50, CI 71, ML 0.41, MI 59, SL 0.46, SI 92, PW 0.31, AL 0.72. Mandible with a small preapical tooth close to the apicodorsal tooth; left mandible also with a vestigial denticle proximal to the preapical tooth (implies possibility of variation such as is common elsewhere in the group). Pronotal humeral hair long, fine and flagellate; all other standing hairs simple or weakly spatulate apically. Without flagellate hairs on dorsolateral margin of head, mesonotum, waist segments or first gastral tergite. The two pairs of standing hairs on cephalic dorsum stiff and erect. Dorsum of head reticulate-punctate, without superimposed rugulose sculpture. Pronotal dorsum shagreenate to finely superficially reticulate-punctate, not sharply reticulate-punctate and without longitudinal rugulae. Mesopleuron mostly smooth, metapleuron and side of propodeum smooth anteriorly, feebly punctulate posteriorly. Propodeum with a pair of narrowly triangular spines, lamella immediately below spine narrow, feebly convex in its lower part around the weakly developed propodeal lacuna. Ventral surface of petiole with a spongiform curtain that at maximum is over half the depth of the peduncle. Dorsum of petiole node slightly longer than broad, weakly reticulate-punctate. Disc of postpetiole unsculptured and basigastral costulae shorter than postpetiole disc.

Type Material

Holotype worker, Costa Rica: Provo Alajuela, Rio Penas Blancas, 10°19'N, 84°43'W, 800 m., 26-28.iv.1987, #1618-S, wet forest, workers on vegetation at night (J. Longino) (The Natural History Museum).

References

• Bolton, B. 2000. The ant tribe Dacetini. Memoirs of the American Entomological Institute. 65:1-1028. (page 513, worker described)

References based on Global Ant Biodiversity Informatics

• Fernández, F. and S. Sendoya. 2004. Lista de las hormigas neotropicales. Biota Colombiana Volume 5, Number 1.
• Longino J. T. 2013. Ants of Nicargua. Consulted on 18 Jan 2013. https://sites.google.com/site/longinollama/reports/ants-of-nicaragua