Leptogenys guianensis

AntWiki - Where Ant Biologists Share Their Knowledge
Jump to: navigation, search
Leptogenys guianensis
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Ponerinae
Tribe: Ponerini
Genus: Leptogenys
Species: L. guianensis
Binomial name
Leptogenys guianensis
Wheeler, W.M., 1923

Leptogenys guianensis casent0178828 profile 1.jpg

Leptogenys guianensis casent0178828 dorsal 1.jpg

Specimen labels

Nothing is known about the biology of Leptogenys guianensis.

Identification

Lattke (2011) - A member of the pusilla species group. Head elongate, eyes flattened placed slightly anterad of lateral cephalic margin mid-distance; propodeal dorsal margin straight in lateral view, dorsal margin of propodeal tooth serrate in lateral view; node trapezoid in dorsal view, anterior and posterior margins parallel, anterior margin half the width of posterior margin.

Keys including this Species

Distribution

The range of Leptogenys guianensis is from French Guiana to northern Brazil.

Distribution based on Regional Taxon Lists

Neotropical Region: Brazil, French Guiana, Guyana (type locality).

Distribution based on AntMaps

AntMapLegend.png

Distribution based on AntWeb specimens

Check data from AntWeb

Biology

The biology of Leptogenys guianensis is poorly known.

The Leptogenys genus page has more details about the general biology of ants in this genus, some of which is summarized in what follows. New World species have relatively small ranges, generally occur in humid forests and prey on isopods. Colonies may occur in high densities on a local scale, with up to 5 or 6 species present. Nest size tends to be small with just 20 or 30 individuals in a mature colony. Nests of most species may be found in rotten wood on the ground, usually within cavities in logs or large branches, and also beneath bark. Wood-soil and rock-soil interfaces are another common nesting location, as well as rock crevices, and a few species may nest directly in the soil. Reproduction is most commonly via ergatoid females and, in many species, may include egg-laying workers.

Castes

Queens and males are unknown.

Nomenclature

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

  • guianensis. Leptogenys (Lobopelta) guianensis Wheeler, W.M. 1923d: 12, fig. 5 (w.) GUYANA. See also: Lattke, 2011: 192.

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

Description

Worker

Lattke (2011) - Metrics (n = 3) : HL 0.89 – 0.97; HW 0.58 – 0.62; ML 0.43 – 0.45; EL 0.12 – 0.14; SL 0.80 – 0.87; PW 0.52 – 0.55; WL 1.32 – 1.40; PH 0.52 – 0.53; PL 0.45 – 0.50; DPW 0.33–0.38 mm. CI 0.64–0.66; MI 0.70–0.74; OI 0.20 – 0.23; SI 1.37 – 1.41; LPI 1.07 – 1.19; DPI 0.74 – 0.81.

Head rectangular in full-face view, slightly wider anterad than posterad; posterior margin straight with vertexal carina visible most of length; lateral cephalic margin mostly broadly convex. Anterior clypeal margin evenly converges anterad to triangular median lobe, apex pointed to slightly blunt; clypeus longitudinally striate medially, laterally with transverse striae. Scape surpasses posterior cephalic border by less than one-fourth its length; densely punctulate; antennal segment III longer than either segments II or IV; segments II and IV each over half the length of III; segment III twice longer than wide. Cephalic dorsum mostly smooth and shining, with sparse piligerous punctulae. Mandibles shut tight against clypeus; elongate, parallel width, basal margin convex, external margin concave; dorsum with sparse punctulae and weak fine, parallel striae; basal angle obtuse, bluntly angular, apical tooth broad, basal margin with two stout hairs; PF: 4,4. Eye flat, situated laterally with slight medial tendency.

Mesosoma with broadly convex promesonotal margin in lateral view, posterior mesonotal margin drops into metanotal groove, dorsal propodeal margin mostly straight, curving onto declivity, propodeal tooth broadly triangular. Mesosoma mostly smooth and shining, with weak, oblique striae on ventral mesopleuron, propodeal spiracle round; mesometapleural suture well impressed, scrobiculate; propodeal spiracle elongate, posterolaterally facing. Mesonotum wider than long in dorsal view, anterior margin curved, posterior margin straight, metanotal groove scrobiculate; propodeal declivity with transverse striae. Petiole subquadrate in lateral view, anterior margin almost half length of posterior margin, dorsal margin mostly sloped with rounded apex, node highest posterad of mid-length; posterior margin mostly straight. Node trapezoid in dorsal view, anterior and posterior margins parallel, anterior margin half the width of posterior margin, gaster smooth and shining with sparse piligerous punctulae. Procoxa smooth and shining laterally, body with sparse standing pilosity, no appressed pilosity. Mandible, clypeus, antennae, and legs light brown; head, mesosoma, petiole and gaster ferruginous brown; apex of protarsus with slender seta; dorsal surface of metacoxa with low posterior lobe. Constriction between abdominal segments III and IV well marked.

Type Material

Syntype workers: Guiana (= British Guiana), Dunoon, 2.viii.1914, Cat. No. 1 – 2, 20508 (F.M. Gaige) (Museum of Comparative Zoology) [examined].

The syntypes are two point-mounted workers on the same pin: MCZ Cotype 1 – 2, 20508. Wheeler’s (1923) description is quite detailed and I agree with all save the extension of the scape beyond the posterior cephalic border, which is one-third according to him. The type series specimens are paler in color than the specimens from Suriname or Brazil.

References