Strumigenys africana

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

Strumigenys africana casent0280697 p 1 high.jpg

Strumigenys africana casent0280697 d 1 high.jpg

Specimen Labels

One of the few specimens of this species was collected from a rainforest litter sample.

Identification

A member of the Strumigenys tetragnatha-group.

Bolton (1983) - The only known close relative of africana is Strumigenys tetragnatha, from Cameroun and Angola. Differences to separate these two species are tabulated under tetragnatha. (reproduced below)

africana tetragnatha
Larger species with shorter antennal scapes, HW 0.70, SI 43. Smaller species with longer antennal scapes, HW 0.49-0.58, SI 47-51.
Lateral margins of head in full-face view with 3 pairs of projecting flagellate hairs. Lateral margins of head in full-face view without flagellate hairs.
Appressed cephalic pilosity longer posteriorly than anteriorly; much longer than the clypeal pubescence. Appressed cephalic pilosity very short, of approximately equal length everywhere; no longer than the clypeal pubescence.
Postpetiole and first gastral tergite with numerous long fine flagellate hairs. Postpetiole and first gastral tergite with simple sparse short straight hairs.

Keys including this Species

Distribution

Distribution based on Regional Taxon Lists

Afrotropical Region: Cameroun, Gabon (type locality).


Distribution based on AntMaps

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Distribution based on AntWeb specimens

Check data from AntWeb

Biology

Castes

Nomenclature

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

  • africana. Glamyromyrmex africanus Bolton, 1983: 322, fig. 27 (w.) GABON. Combination in Pyramica: Bolton, 1999: 1672; in Strumigenys: Baroni Urbani & De Andrade, 2007: 115. See also: Bolton, 2000: 329.

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 3.0, HL 0.82, HW 0.70, CI 85, ML 0.16, MI 20, SL 0.30, SI 43, PW 0.36, AL 0.68.

Mandibles with a broad basal lamella (partially visible as mandibles slightly opened) followed by a principal dental row of 5 large triangular teeth which are slightly recurved and evenly spaced on the strongly downcurving arch of the mandibular masticatory margin. Basalmost tooth following the lamella without a diastema, slightly smaller than the second tooth. Third tooth from the basal lamella the largest, fourth and fifth tooth slightly smaller. Distal to the principal dental row is a series of three denticles which share a common base. In profile the mandibles rapidly increasing in width from base to apex, the upper and lower borders strongly divergent, the former arching up above the level of the anterior clypeal margin, the latter shallowly concave and downcurved; apical margin as seen in profile strongly arched-convex. With the head in full-face view the anterior clypeal margin with a concave median indentation, the clypeus broad but the lateral free margins not extended into lobes and noticeably narrower than the sides of the head behind the clypeus. Sides of head evenly shallowly convex, broader behind than in front. Occipital margin extended backwards as a rounded lobe on each side of a central broad impression, the median portion of which is transverse. The margin of the occipital impression bounded on the dorsum by a continuous low rim or crest. Dorsum of head behind clypeus raised medially into a broad tumulus which is convex in both directions but does not reach the lateral margins; rather the tumulus is surrounded on all sides by more or less flat areas of cuticle. Frontal lobes and frontal carinae fused to form a continuous upper scrobe margin which is strongly prominent laterally, conceals the scrobes from dorsal view, and is continuous with the flattened posterolateral portions of the head. Antennal serobes deep and extensive, anteriorly divided into upper and lower compartments by the weak preocular laminae and with the small eye situated on the ventral scrobe margin. In profile the dorsal cephalic tumulus is balanced by an even more strongly prominent mid-ventral tumulus whose maximum convexity occurs at about the level of the eye and behind which the ventral surface is markedly concave. Antennal scapes short (SI 43) and feebly clavate, not bent near the base, the leading edge evenly shallowly convex and lacking projecting hairs. Dorsum of head with dense abundant decumbent to appressed fine simple hairs, shortest near the clypeus (which has only minute fine pubescence) and longest occipitally, directed anteriorly or anteromedially and densest on the lateral margins; the latter also with 3 pairs of long projecting flagellate hairs. Dorsum of head with minute shallow pits from which the hairs arise, otherwise unsculptured except for a feeble superficial shagreening in places; clypeus smooth. Sides of alitrunk sharply laterally marginate throughout, most strongly so on the pronotum where the marginations are prominent and overhang the sides. Pronotum also marginate anteriorly and with a median longitudinal ridge or carina dorsally. Dorsum of mesonotum separated from the short propodeal dorsum by a low transverse crest; metanotal groove absent. Propodeal teeth very broad basally, rapidly tapering apically and with the extreme apices upcurved. Infradental lamellae much narrower than the propodeal teeth, the latter with more than half their length standing free of the lamellae. Sides of alitrunk unsculptured except for the punctate mesopleuron. Dorsal alitrunk with a few superficial rugular vestiges on the promesonotum but only the median carina conspicuous. Lateral margination of the alitrunk with 2-3 long flagellate hairs on each side, otherwise the dorsum and margins only with fine scattered simple pilosity. Peduncle of petiole long, the node bluntly triangular in profile. Spongiform ventral process of petiole peduncle massively developed and curtain-like, about as deep as the node is high. Other spongiform material on petiole reduced to a pair of short aliform prominences situated lateroventrally when the node is viewed from above and from which a narrow crest arises which follows the posterior margin of the node. Petiole node sparsely rugulose, disc of postpetiole sparsely irregularly longitudinally costulate. Ventral spongiform appendages of postpetiole moderate, the lateral appendages narrow in dorsal view, broadest at the posterolateral angles. Anterior face of postpetiolar disc with a narrow bordering lamella, the posterior margin without spongiform material, bordered instead only by a sharp narrow and shallowly convex rim which abuts a similar but concave rim bordering the base of the first gastral tergite. First gastral tergite without basal spongiform material but with a lamellate area laterobasally, immediately behind the lateral appendages of the postpetiole; this lamellate area thrown into strong ridges which form the origins of the lateral basigastral costulae. First gastral sternite without a basal spongiform pad. Primary basigastral costulae, arising at the base of the tergite, few in number and mostly lateral in origin; more posteriorly numerous finer costulae arise which form a dense band over about one-third of the length of the tergite. Petiole, postpetiole and first gastral tergite with numerous long fine flagellate hairs. Black, the spongiform appendages pale.

Type Material

Holotype worker (gold-palladium coated), Gabon: Makokou, berlese no. 17, x-xii. 1972, rain forest (I. Lieberburg) (Museum of Comparative Zoology).

References