Strumigenys anarta

Strumigenys anarta
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Myrmicinae
Tribe:	Attini
Genus:	Strumigenys
Species:	S. anarta
Binomial name
Strumigenys anarta (Bolton, 1983) Specimen Labels

The type material was collected from "coast vine on sand." A second collection was made from a litter sample in montane forest.

Identification

Bolton (2000) - A member of the Strumigenys oxysma-group. Dorsolateral margin of head in full-face view with a single laterally projecting flagellate hair, located close to the occipital corner and frequently lost; no flagellates arise from the upper scrobe margin. Dorsum of clypeus with 18 recurved short spoon-shaped hairs. Lateral clypeal margins with recurved short spoon-shaped hairs that are sparse and quite closely applied to the surface.

Bolton (1983) - To the present only two species of this group are known. They are separated easily as in anarta the clypeal dorsum has 18 recurved hairs, the upper scrobe margins lack flagellate hairs, the cephalic dorsum lacks flagellate hairs, and the first gastral tergite has only 4 standing hairs arranged in a transverse row close to the base of the sclerite. In contrast Strumigenys oxysma has 12 recurved hairs on the clypeal dorsum, has 3 pairs of flagellate hairs on the upper scrobe margins, has flagellate hairs present on the cephalic dorsum, and has 12 or more standing hairs on the first gastral tergite which are distributed all over the sclerite.

Keys including this Species

• Key to Afrotropical Strumigenys (as Pyramica)

Distribution

Latitudinal Distribution Pattern

Latitudinal Range: -31.45° to -34.06667°.

North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

• Source: AntMaps

Distribution based on Regional Taxon Lists

Afrotropical Region: South Africa (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. ‎

Nomenclature

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

• anarta. Smithistruma anarta Bolton, 1983: 314, fig. 18 (w.) SOUTH AFRICA. Combination in Pyramica: Bolton, 1999: 1673; in Strumigenys: Baroni Urbani & De Andrade, 2007: 115. See also: Bolton, 2000: 323.

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 1.9, HL 0.54, HW 0.34, CI 63, ML 0.06, MI 11, SL 0.27, SI 79, PW 0.21, AL 0.48.

Principal dental row of mandible with 7 teeth, followed by 4 minute denticles and a small apical tooth. Basal lamella of mandible (concealed by clypeus in holotype) a long low rounded lobe which is only as high as the basal most tooth; no diastema between basal lamella and basalmost tooth. In full-face view the clypeus with shallowly convex sides which are evenly convergent anteriorly and with a strongly convex anterior margin which is narrowly rounded medially; the anterior margin on each side of the midpoint forms a single evenly convex line which is continuous with the lateral margins, without trace of an anterolateral angle. Outer margins of the fully closed mandibles forming a more or less continuous line with the outer margins of the clypeus in full-face view. Clypeal margins without a fringe of anteriorly or medially curved large spatulate hairs but one or two simple short hairs may occur posterolaterally. The dorsum of the clypeus along the anterior margin with 3 pairs of short recurved spatulate hairs which curve upwards and backwards from the clypeal edge. Behind this anterior row the clypeal dorsum with 12 similar curved hairs. These 12 make up four pairs which are situated on each side of the midline and which curve backwards and towards the midline, the posteriormost pair being at the posteromedian clypeal apex; a pair on the posterior clypeal margin immediately in front of the anteriormost part of the frontal lobes, curved in the direction of the clypeal margin; and a pair situated posterolaterally on the clypeus, curved towards the midline and slightly backwards. Cephalic dorsum behind clypeus with subdecumbent to decumbent short narrowly spatulate hairs which are curved towards the highest point of the vertex. Flagellate hairs absent from dorsum of head and from upper scrobe margins. Antennal scapes slender, not flattened, narrowed basally and bent at about the basal quarter. Leading edges of scapes without a freely projecting row of long hairs, only with short fine pubescence which is decumbent to appressed. Maximum diameter of eye 0.12 X HW. Clypeus finely punctulate, cephalic dorsum reticulate-punctate. Anterior pronotal border sharply transversely marginate. Sides of pronotum not marginate but sides of mesonotum and propodeum angulate. Pronotum with a median longitudinal ridge or carina dorsally. Metanotal groove visible on the dorsal alitrunk but not impressed in profile. Propodeal teeth short and confluent with the broad infradental lamellae. Pronotal humeri each with a long flagellate hair. Posterodorsally on the mesonotum is a pair of somewhat flattened hairs which are markedly curved towards the midline and are notched apically. Dorsal ground-pilosity of alitrunk consists of a very few decumbent to appressed scattered short hairs, most easily visible on the anterior half of the pronotum. Dorsal surfaces of petiole and postpetiole with numerous back-curved hairs. First gastral tergite with 4 standing hairs only, which are blunted or notched apically and arranged in a transverse row close to the base of the sclerite. Behind this are sparse flattened short appressed hairs on the remainder of the tergite which are directed towards the midline. Sides of alitrunk unsculptured. Dorsal alitrunk unsculptured apart from the median carina and some extremely faint, almost effaced, sculptural vestiges on the promesonotum. Dorsum of petiole node densely punctate, postpetiolar disc glassy smooth. First gastral tergite unsculptured except for the sparse basal costulae which are arranged on each side of a central clear area. Spongifirm appendages of pedicel segments strongly developed in profile. In dorsal view the petiole node bounded posteriorly by a narrow lamellar strip. Shallowly concave anterior margin of postpetiole with a narrow lamellar strip. Ventrolateral spongiform appendages of postpetiole not visible in dorsal view. Posterior margin of postpetiole with a lamellar strip and the margin of the disc indented medially. Basal border of first gastral tergite with a sinuate lamella whose free margin is concave medially and convex towards the sides. Colour dull glossy yellow.

Paratype. TL 1.9, HL 0.55, HW 0.36, CI 65, ML 0.06, MI 11, SL 0.28, SI 78, PW 0.22, AL 0.50. As holotype.

Type Material

Holotype worker, South Africa: Natal, Dukuduku Forest Res., 12-15 km E. of Mtubatuba, coast vine forest on sand, 26.1.1977 (W. L. & D. W. Brown) (Museum of Comparative Zoology). Paratype. 1 worker with same data as holotype (The Natural History Museum).

References

• Baroni Urbani, C. & De Andrade, M.L. 2007. The ant tribe Dacetini: limits and constituent genera, with descriptions of new species. Annali del Museo Civico di Storia Naturale “G. Doria” 99:1-191.
• Bolton, B. 1983. The Afrotropical dacetine ants (Formicidae). Bulletin of the British Museum (Natural History). Entomology 46:267-416. (page 314, fig. 18 worker described)
• Bolton, B. 1999. Ant genera of the tribe Dacetonini (Hymenoptera: Formicidae). Journal of Natural History. 33:1639-1689. (page 1673, combination in Pyramica)
• Bolton, B. 2000. The ant tribe Dacetini. Memoirs of the American Entomological Institute. 65:1-1028. (page 323, redescription of worker)

References based on Global Ant Biodiversity Informatics

• Bolton, B. 2000. The Ant Tribe Dacetini. Memoirs of the American Entomological Institute 65