The Ants of Africa
Contents - Myrmicinae - MYRMICINAE Introduction

Genus Pristomyrmex Mayr (1866b: 903)


Diagnostic Features - Head broader in front than behind, sides convex. Distal portion of mandible in anterior view suddenly broadened. Median portion of clypeus with a number of blunt teeth on the anterior margin; lateral portions reduced to a thin raised strip in front of the antennal insertions. Antennae 11-segmented, with a 3-segmented club. Eyes medium or small, about the midlength of the head. Dorsum of alitrunk without sutures. Pronotum usually with a pair of spines or blunt tubercles. Propodeum bispinose or bidentate. Sting simple, without an apical spatulate lamella.

Mayr's (1866b) genus description is at {original description}.

According to Bolton (1973a) the genus could be confused with some species of Xiphomyrmex (now synonymised with Tetramorium) but the sting has no spiculate apical portion. Members nest in rotten wood or fallen twigs in the leaf litter, foraging in the same area.

Revised by Bolton (1981b). Most species are leaf litter dwellers, nesting in rotten wood.

Key to workers known from Africa

1 {Pristomyrmex cribrarius alitrunk dorsum}TL 3.2-3.4 mm; petiole and postpetiole with lateral coarse sculpture; the only species with quite dense short pilosity; head behind the eyes with projecting short hairs; brown, gaster darker than head and alitrunk, appendages lighter .
. {Pristomyrmex cribrarius} southern Africa - cribrarius
-- Petiole and postpetiole with sides smooth and shining; head behind the eyes without projecting short hairs 2
2 {Pristomyrmex trogor}TL 3.4-4.0 mm; without frontal carinae and very short frontal lobes; scapes reaching occiput (SI 101); shiny chestnut brown .
. {Pristomyrmex trogor} Eastern Zaire - trogor
-- With distinct frontal carinae; scapes shorter (SI 82-90) 3
3 With small eyes and pronotum armed with distinct sharp teeth or spines 4
-- With relatively large eyes (8-10 ommatidia long); pronotum with no more than low tubercles 5
4 {Pristomyrmex africanus alitrunk profile}TL 2.7-3.4 mm, CI 97-104, SI 85-94; antennal scapes distinctly sinuous with an out-turned apex; spines on pronotum and propodeum only moderately long and generally not very sharp; head with quite abundant foveae and semi-erect pilosity; colour varying from orange-brown to blackish-brown, gaster often darker .
. {Pristomyrmex africanus} western Africa, south to Angola - africanus
-- {Oligomyrmex usambarensis}TL 3.2 mm, CI 104, SI 78; almost wholly unsculptured, except for minute hairs pits on the front of the head; mandibles apparently with distinct teeth; antennal scapes near straight; pronotum with long acute spines that are very narrow in frontal view; shiny, dark red brown with distinct lighter areas, notably on the frons and pedicel Tanzania (Usambara Mts) - new species - usambarensis
5 {Pristomyrmex orbiceps}TL 2.9-3.4 mm, head wider than long, CI 100-106, SI 80-87; front of head smooth and shining; eye moderate; profile of petiole node not wedge-shaped; blackish-brown to black .
. {Pristomyrmex orbiceps} western Africa, south to Angola - orbiceps
-- {Pristomyrmex fossulatus}TL 2.7-3.2 mm, CI (Bolton) 95-97; front of head with distinct fovea; eye ca 0.25 HW; clypeus with sharp median carina; profile of petiole node wedge-shaped; shiny light brown South Africa - fossulatus
Contents MYRMICINAE Introduction
2007, 2008, 2010, 2013 - Brian Taylor CBiol FSB FRES
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