Monomorium exiguum Forel

Type location Ethiopia (Forel, 1894b: 85, worker); junior synonyms bulawayensis (Forel, 1913j: 217, worker) from Zimbabwe, faurei from Gabon (Santschi, 1915c: 260, illustrated, worker) collected at Samkita by Faure; and flavescens from Zaïre (Forel, 1916: 418, worker) collected at St. Gabriel, by Kohl (see Bolton, 1987, 1995); minutissimum (Monomorium minutissimum, Santschi, 1937d, illustrated, worker) from Angola - synonymy by Heterick (2006: 115); .

Forel's (1894b) description is at . Forel's (1913j) description of bulawayensis is at . Arnold (1916: 238) gave a translation of bulawayensis is at . Santschi's (1915c) description of faurei is at . Forel's (1916) description of flavescens is at . Santschi's (1937d) description of minutissimum is at . Bolton's modern description (1987) is at . Heterick's further description (2006: 115) is at .

In Ghana, at CRIG (B. Bolton), Kibi and Legon (D. Leston), Mampong and Tumu (P.M. Room), Boku and Pankese (C. A. Collingwood) (Bolton, 1987). Later, it was described as widespread, by Belshaw & Bolton (1994b), who found 605 workers from leaf litter samples at 16 locations in the semi-deciduous forest zone.

From Ivory Coast, at a site 40 km west of Abidjan (W.L. Brown); Cameroun, at Nko'emvon (D.A. Jackson); and throughout central and eastern Africa (Bolton, 1987). Wheeler (1922) also had it (as faurei) from Guinea, at Mamou (F. Silvestri). Bequaert (1922, p407) cited it as one of the species collected from myrmecophilous plants by Father H. Kohl, near Kisangani (Stanleyville) (as flavescens; in Forel, 1916).

Separation of populations (in part from statements in Heterick, 2006).

Monomorium exiguum sensu stricto (Heterick, 2006, designated lectotype from orginal collection). The photograph from Heterick's paper is much paler than Heterick's description. the specimen below from Gabon shows the dark colour so. perhaps, that in Heterick's photo has faded with age

The photomontage is of a specimen from Gabon, Pongara National Park; Gabon 100; 24.vii.2006; under or on bark of Okoume; collected by Yves Braet, apparently matching the type form. Other images can be seen in the folder at .

Monomorium exiguum bulawayense lectotype designated by Heterick (2006) as populations with relatively pale workers with a strongly constricted alitrunk (mesosoma). The photomontage of the bulawayensis type from Zimbabwe is collated from http://www.antweb.org/specimen.do?name=casent0010763

The photomontage is of a dark brown specimen from Ghana, collected by S Sky Stephens, 2006; this appears to be close to the bulawayensis form. Other images can be seen in the folder at - .

Monomorium exiguum faurei lectotype designated by Heterick (2006) as having populations with a slightly bicoloured appearance (yellowish-brown head and gaster; yellowish alitrunk, appendages and base of gaster (lectotype).

Santschi's (1915c) description of faurei is -
WORKER - TL 1.3-1.5; Head a quarter longer than wide; sides slightly arcuate, posterior border feebly convex. Mandibles with 4 teeth, the inner teeth somewhat reduced. Clypeus with indistinct carinae. Eyes in anterior third of sides. Scapes reaching the posterior fifth of head; segment 1 of the funiculus as long as wide; segments 4-8 a quarter to half slimmer than long; apex of club as long as preceding eight segments together. Propodeum a little less convex than in orientale (from India) but more convex than clavicorne variety punicum (from Tunisia). Pedicel nodes equally wide; petiole a good third higher than postpetiole.
Colour deep yellow; head, two areas on each side of first gastral segment and following segments, brown yellow, except on the posterior borders. Smooth and shiny. Pilosity sparse; antennae pubescent.
Several workers from Gabon, by F. Faure; others from Guinea, at Mamou, by Silvestre (originally noted in Santschi, 1914d) as atomus stirps mictilis Forel; now regarded as sp. mictile from Ethiopia and Sudan).

The photomontage is of a specimen from Ghana, collected by S Sky Stephens, 2006; this show the bicoloured pattern, including the pale base to the gaster. Other images can be seen in the folder at - .

Nigerian specimen - probably also faurei (Taylor, 1980a: 33) TL 1.63 mm, HL 0.40, HW 0.34, SL 0.31, PW 0.23 (in my Guide as Monomorium species T²). Others TL 1.5-1.7 mm (Bolton, 1987: 388, not illustrated).
Colour yellow, head and gaster more brown. Eleven-segmented antennae. Cuticle of head translucent. Lateral mesonotum and propodeum very finely rugoreticulate. Erect hairs moderately long but relatively sparse. Otherwise as key.

In Nigeria, from CRIN (B. Bolton; B. Taylor). I collected it from a leaf on a low shrub under forest shade.

Monomorium exiguum minutissimum paralectotype designated by Heterick (2006) as populations similar to faurei but (perhaps) with more deeply incised metanotal groove.

The photomontage is of a specimen apparently matching Santschi's minutissimum description and illustration, from Gabon, Pongara National Park; Gabon 114; 1-8.viii.2006; sweep net of sesame & forest; collected by Yves Braetcollected by Yves Braet; e.g the head shape in full face view and the lateral short low petiole. Other images can be seen in the folder at .

Also others from Congo, Brazzaville, 19.viii.2007; t 1.10; 24 h pitfall trap; collected by Yves Braet & Eric Nzassi, in .