Strumigenys bernardi

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Strumigenys bernardi
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Strumigenys
Species: S. bernardi
Binomial name
Strumigenys bernardi
Brown, 1960

Strumigenys bernardi casent0217946 p 1 high.jpg

Strumigenys bernardi casent0217946 d 1 high.jpg

Specimen Labels

Relatively well collected for an Afrotropical Strumigenys, the dozens of collections of this species have been collected across a wide range of forest habitats. Most specimens have been obtained via litter sampling and pitfall traps.

Identification

Bolton (2000) - A member of the rogeri complex in the Strumigenys rogeri -group. Very color variable, ranging from clear straw-yellow to almost black.

Bolton (1983) - Among the Afrotropical Strumigenys in which the preocular notch is developed bernardi and Strumigenys vazerka form a close species-pair characterized by their long bowed mandibles, long scapes, lack of intercalary teeth in the mandibular apical forks, and by having the pre ocular notch continued as an impression on the ventral surface of the head. Most samples of bernardi are instantly distinguishable from vazerka as the former has only a single preapical tooth on the left mandibular blade whilst the latter has two. However, now and again a specimen of bernardi with a minute vestige of the left distal preapical tooth is found, but here bernardi is recognized by its reticulate-punctate propodeal dorsum, which in vazerka is smooth.

Keys including this Species

Distribution

Distribution based on Regional Taxon Lists

Afrotropical Region: Angola, Cameroun, Democratic Republic of Congo (type locality), Equatorial Guinea, Gabon, Uganda.


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.

  • bernardi. Strumigenys bernardi Brown, 1960c: 206 (w.) DEMOCRATIC REPUBLIC OF CONGO. See also: Bolton, 1983: 356k; Bolton, 2000: 601.

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

Description

Worker

Bolton (1983) - TL 1.7-2.1, HL 0.52-0.58, HW 0.36-0.41, CI 67-72, ML 0·30-0.36, MI 55-65, SL 0.30-0.36, SI 82-92, PW 0.22-0.26, AL 0.44-0.54 (25 measured).

Mandibles long and slender, conspicuously bowed outwards in full-face view. Apical fork of both mandibles without intercalary denticles. Left mandible usually with only a single spiniform preapical tooth (the proximal) but extremely rarely a minute almost invisible distal pre apical denticle can be seen very close to the dorsal tooth of the apical fork. Right mandible with 2 pre apical teeth, the proximal much longer than the distal and the latter frequently concealed by the opposing upper fork tooth when the mandibles are closed. Upper scrobe margins close together immediately behind the frontal lobes, usually feebly sinuate close to the frontal lobes and then evenly divergent behind, not concave or impressed above the eyes and without a conspicuous bordering lamella or flange. Pre ocular notch strongly developed and deep, the anterior portion of the eye detached from the side of the head. Preocular notch continuing onto ventral surface of head as a transverse impression. Maximum diameter of eye equal to or greater than maximum width of scape. Antennal scapes straight and slender, the leading edge with a row of apically curved narrowly spatulate hairs. Cephalic ground-pilosity of inconspicuous narrowly spatulate hairs which are curved anteriorly. Laterally projecting curved spatulate to spoon-shaped hairs which border the upper scrobe margins distinctly larger than the ground-pilosity. Vertex of head with 6 standing hairs arranged in a row of 4 close to the occipital margin and a more anteriorly situated pair. Dorsum of head finely and shallowly reticulate-punctate everywhere. Pronotal humeri each with a long fine flagellate hair and the mesonotum with a single pair of stout standing hairs. Ground-pilosity on alitrunk minute and appressed. Metanotal groove represented by a transverse line on the dorsum, not or only vestigially impressed in profile. Posterior portion of mesonotum depressed and on same level as propodeum, the latter armed with a pair of triangular teeth subtended by narrow infradentallamellae. Pleurae of alitrunk smooth and shining or at most with faint peripheral punctulae. Sides of propodeum usually punctate, less commonly virtually unsculptured. Pronotal dorsum usually with fine longitudinal rugulae which diverge posteriorly and are superimposed on a punctate ground-sculpture, but one or the other component may be emphasised so that at one extreme the pronotum is punctate dorsally and at the other almost entirely rugulose. Mesonotum and propodeum reticulate-punctate dorsally. Petiole node punctate dorsally, the postpetiole smooth or weakly sculptured, often with feeble longitudinal costulae and sometimes with vestigial punctures. Petiole with a vestigial ventral appendage which at most is represented by a narrow carina, the node posteriorly with a slender transverse collar. Ventral spongiform lobe of postpetiole moderately developed, larger than the lateral lobe in profile. In dorsal view the postpetiole with a very narrow anterior and broader posterior spongiform strip. Base of first gastral tergite with a narrow lamellar strip from which the basigastral costulae arise. Petiole, postpetiole and gaster with strong hairs which are weakly clavate apically. Colour dull yellow.

Type Material

Holotype worker, ZAIRE: 10 miles (16 km) E. of Stanleyville (= Kisangani), iii.1948, no. 2225 (N. A. Weber) (Museum of Comparative Zoology) [examined]

References