Monomorium trake

Known from numerous types of mesic forest habitats and, based on collection records from various locations (live stem, dead branch, rotten log, nest into stone), will nest in any kind of cavity on or above the ground surface. In Benin, Taylor et al. (2018) found it on mango (Mangifera indica) trees.

Identification
Bolton (1987) - One of only 6 species to combine 12-segmented antennae with the reduced form of eye described above, trake is isolated from the other five species sharing these characters by its very short antennal scapes, SI 73. In the remaining species (Monomorium shilohense, Monomorium rotundatum, Monomorium sryetum, Monomorium floricola and Monomorium inquietum) SI is >75, usually >80. Other differentiating characters are noted under the names of the other five species.

Distribution based on Regional Taxon Lists
Afrotropical Region: Benin, Central African Republic, Ghana, Uganda, United Republic of Tanzania.

Nomenclature

 * . Monomorium trake Bolton, 1987: 417 (w.) GHANA.
 * Type-material: holotype worker, 3 paratype workers.
 * Type-locality: holotype Ghana: Aburi, 22.iii.1969 (P. Room); paratypes with same data.
 * Type-depositories: BMNH (holotype); BMNH, MCZC (paratypes).
 * Status as species: Bolton, 1995b: 268.
 * Distribution: Ghana.

Worker
Holotype. TL 1.6, HL 0.39, HW 0.30, CI 77, SL 0.22, SI 73, PW 0.19, AL 0.40.

Mandible equipped with three strong teeth and a minute offset basal denticle. Anterior clypeal margin more or less evenly convex between the inner borders of the mandibles, without a strongly differentiated prominent median section. Clypeal carinae feebly developed, widely divergent anteriorly. Eye in profile small, its length only slightly greater than its height and the maximum diameter of the eye 0.18 x HW. Ommatidia of eye arranged as an outer ring which surrounds a single longitudinal row, the encircled row consisting of only two ommatidia. In full-face view the eyes distinctly in front of the midlength of the sides. Antennal scapes relatively very short, SI < 75; when laid straight back from their insertions the scapes conspicuously failing to reach the occipital margin. Promesonotal dorsum evenly shallowly convex in profile, sloping posteriorly to the extremely feebly impressed metanotal groove. Propodeal spiracle small, pinhole-like. Node of petiole low and bluntly rounded dorsally, the anterior peduncle short and subtended by a strip-like ventral process which runs from close to the insertion to the strong posteroventral bulge of the petiole. Postpetiole smaller than petiole and only slightly more broadly rounded dorsally. Standing hairs present on all dorsal surfaces but everywhere sparse ; the promesonotum with 5 pairs, the propodeum with a single pair. Sculpture absent except for short cross-ribs at the metanotal groove. Colour uniform yellow except for apex of first gastral tergite which is traversed by a band of brown.

Paratypes. TL 1.6, HL 0.38-0.39, HW 0.30, CI 77-79, SL 0.22, SI 73, PW 0.18-0.19, AL 0.38-0.40 (3 measured). As holotype but maximum diameter of eye 0.17-0.18 x HW. Only one of the paratypes shows its full complement of alitrunk pilosity, the other two both show signs of abrasion.

Type Material
Holotype worker, Ghana: Aburi, 22.iii. 1969 (P. Room). Paratypes. 3 workers with same data as holotype (BMNH; ).

References based on Global Ant Biodiversity Informatics

 * Belshaw R., and B. Bolton. 1994. A survey of the leaf litter ant fauna in Ghana, West Africa (Hymenoptera: Formicidae). Journal of Hymenoptera Research 3: 5-16.
 * Belshaw R., and B. Bolton. 1994. A survey of the leaf litter ant fauna in Ghana, West Africa (Hymenoptera: Formicidae). Journal of Hymenoptera Research. 3: 5-16.
 * Bolton B. 1987. A review of the Solenopsis genus-group and revision of Afrotropical Monomorium Mayr (Hymenoptera: Formicidae). Bulletin of the British Museum (Natural History). Entomology 54: 263-452.
 * Stephens S. S., P. B. Bosu, and M. R. Wager. 2016. Effect of overstory tree species diversity and composition on ground foraging ants (Hymenoptera: Formicidae) in timber plantations in Ghana. International Journal of Biodiversity Science, Ecosystem Services & management 12(1-2): 96-107.
 * Taylor B., N. Agoinon, A. Sinzogan, A. Adandonon, Y. N'Da Kouagou, S. Bello, R. Wargui, F. Anato, I. Ouagoussounon, H. Houngbo, S. Tchibozo, R. Todjhounde, and J. F. Vayssieres. 2018. Records of ants (Hymenoptera: Formicidae) from the Republic of Benin, with particular reference to the mango farm ecosystem. Journal of Insect Biodiversity 8(1): 006–029.