Strumigenys paranetes

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Strumigenys paranetes
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Strumigenys
Species: S. paranetes
Binomial name
Strumigenys paranetes
Brown, 1988

Strumigenys paranetes casent0280758 p 1 high.jpg

Strumigenys paranetes casent0280758 d 1 high.jpg

Specimen Labels

The type material was taken from a rotten log in rainforest. Subsequent collections are from litter samples in wet forests.

Identification

Bolton (2000) - A member of the Strumigenys mayri-group. This species separates easily from Strumigenys orthanetes as the latter has a preapical denticle on the mandible, a pair of erect hairs on the pronotal dorsum and is lighter in colour. Respective shape of the propodeal lamella is the easiest way to distinguish Strumigenys anetes from paranetes, but the former is also a larger, more lightly coloured species with somewhat longer scapes. The ventrolateral margin of the head, immediately in front of the eye, has a small, shallow but distinctive U-shaped impression in paranetes, whereas any preocular impression of the margin in anetes is minute or vestigial. As noted in the key, the easiest way to separate paranetes from Strumigenys dysanetes is to check the relative lengths of the mandibles and scapes. Apart from this dysanetes has a very conspicuously impressed area posteromedially on the cephalic dorsum.

Keys including this Species

Distribution

Distribution based on Regional Taxon Lists

Australasian Region: Australia (type locality).

Distribution based on AntMaps

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Distribution based on AntWeb specimens

Check data from AntWeb

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

Nomenclature

The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.

  • paranetes. Strumigenys paranetes Brown, 1988g: 43, 2 figs. (w.) AUSTRALIA. See also: Bolton, 2000: 980.

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

Description

Worker

Bolton (2000) - TL 2.3-2.5, HL 0.68-0.77, HW 0.46-0.54, CI 65-70, ML 0.31-0.36, MI 45-47, SL 0.44-0.50, SI 88-96, PW 0.25-0.29, AL 0.63-0.70 (20 measured).

Answering the description of anetes but smaller and with the scapes averaging shorter (compare measurements). Lamella on the propodeal declivity broad in paranetes, its posterior (free) margin convex. Darkly coloured species, uniform dark brown to blackish brown.

Type Material

Bolton (2000) - Holotype worker and paratype workers, AUSTRALIA: Queensland, Malanda, 6 & 7.xi.1950, rain forest, rotten log (W. L. Brown) (Museum of Comparative Zoology) [examined].

When describing Strumigenys anetes Brown (1988) stressed that it, and its close relative paranetes, were “without any trace of a preapical tooth”. However, a series that he included as paratypes of paranetes (AUSTRALIA: Atherton, xii.1957-ii.1958 (P. F. & P. J. Darlington) possess a preapical denticle. They also differ from both anetes and paranetes by having a pair of erect hairs on the pronotal dorsum, in addition to the humeral hairs, and obviously represent a separate species. To straighten out this anomaly I have restricted the type-series of paranetes to the holotype and other members of its series and removed the Atherton series to Strumigenys orthanetes; this series now has no type-status. Two other series included by Brown as paratypes of paranetes have not been seen (West slope Mt Bartle Frere, 900-1500 m, xii.1957 (Darlingtons); series with no locality data (T. E. Woodward). These are also here excluded from the type-series of paranetes. Their exact identity remains to be confirmed; specimens are probably in MCZ, ANIC, or both.

Description

References

  • Bolton, B. 2000. The ant tribe Dacetini. Memoirs of the American Entomological Institute. 65:1-1028. (page 980, redescription of worker)
  • Brown, W. L., Jr. 1988g. Strumigenys paranetes species nov. Pilot Regist. Zool. Card No. 43. (page 43, 2 figs. worker described)