Monomorium dentatum sp. n., a new ant species from Egypt (Hymenoptera: Formicidae) related to the fossulatum group. Sharaf, M. R. Zoology in the Middle East 2007 41 93 98 urn:lsid:biosci.ohio-state.edu:osuc_concepts:225935 Insecta Formicidae Monomorium CoL Animalia Monomorium dentatum Sharaf Hymenoptera 94 Arthropoda species dentatum  (Figs 1 & 2)    Holotype. Worker, Egypt, Damietta,  20.viii.2003, 31°26'N, 31°48'E, leg. M. R. Sharaf. -  Paratypes: 17 workers, same series as holotype, 13 workers, Abu-Swelem, El-Minyia,  29.vi.2003, 28°06'N, 30°45'E, leg. M. R. Sharaf; 3 workers, Abuzabal, Qalyubiya,  21.vi.2003, 30°03'N, 31°15'E, leg. M. R. Sharaf; 1 worker, Port Said,  26.viii.2003, 31°16'N, 32°18'E, leg. M. R. Sharaf.    Fig. 1. Profile of Monomorium dentatum sp. n.  Fig. 2. Full-face view of Monomorium dentatum sp. n.  Measurements of workers [holotype in brackets], TL 1.49-1.63 [1.63]; HL 0.39-0.43 [0.41]; HW 0.33-0.36 [0.34]; CI 82.9-92.3 [82.9]; SL 0.34-0.35 [0.34]; SI 98.6-101.4 [100]; EL 0.02 [0.028]; PL 0.184-0.210 [0.184]; PW 0.110-0.120 [0.113]; PPL 0.110-0.127 [0.127]; PPW 0.09- 0.127 [0.127] (13 specimens measured including the holotype and the same series,  Damietta,  20.viii.2003, 31°26'N, 31°48'E). Worker description. A unicolorous yellow, smooth, shining and slightly hairy ant. Monomorphic with very small size variation within the same nest. Head clearly longer than broad, smooth and shining with abundant, minute and scattered hair pits on the dorsum; sides of head with dense and relatively long yellow hairs. Mandibles armed with 4 teeth, the 3rd and the 4th teeth not close to each other; the whole mandible surface with relatively long and abundant yellow hairs. Frontal carinae very short; the area behind the lateral clypeal margins and adjacent to antennal insertions widely depressed. Antennae 12-segmented with a well defined 3-segmented club; antennal scapes with abundant and relatively long hairs; funiculus with very short and dense hairs; antennal club with very dense pubescence; the terminal funicular segment clearly longer than the two preceding segments together; the 2nd to 8th funicular segments clearly wider than long. Eyes very tiny with one ommatidium. Occiput raised. Pronotum sides smooth; promesonotum in profile with dorsal outline evenly convex; metanotal groove sharply defined as a U-shaped impression; junction of propodeal dorsum and declivity equipped with a pair of minute tubercles or tiny denticles; propodeal spiracles relatively large and round; lower part of mesopleuron faintly but conspicuously punctulateshagreenate; impression between mesopleuron and metapleuron faintly cross-ribbed. Pronotum with about 9 pairs of relatively long erect hairs; mesonotum with 3 pairs, propodeal dorsum with 2 pairs of hairs. Petiole pedunculate, with a high rounded node and one pair of long hairs; subpetiolar process simply dentiform. Postpetiole as long as broad, with one or two pairs of hairs. Gaster smooth and shining with abundant scattered and relatively long hairs. Dorsal surfaces of head, alitrunk and gaster unsculptured except for scattered hair-pits.  Remarks. This new species is a member of the Monomoriumfossulatum-group as defined by Bolton (1987) and cannot be identified with any of the Monomoriumspecies in Bolton's key to the Afrotropical species. M. dentatumappears taxonomically closest to M. sersalatum Bolton, 1987, which was described from Rwanda, and M. thrascoleptum Bolton, 1987, which was described from Ivory Coast. All three species are uniformly yellow; the promesonotum profile is evenly convex, the propodeum immediately behind the metanotal groove rises to an acute peak then slopes posteriorly to a pair of distinct projecting denticuliform angles at the junction of the dorsum and declivity; the propodeum with two or three pairs of hairs; the scapes and sides of the head behind the eyes have erect to suberect pubescence; sides of pronotum are smooth; and the area between the mesopleuron and metapleuron is faintly cross-ribbed.  M. dentatummay be closer to M. thrascoleptum, but is consistently smaller, TL 1-49-1.63 versus TL 1.9-2.2 mm; has a lower scape index, SI<100 versus SI 103-110; and M. dentatumalso has sculpturation on the mesopleuron, which is smooth in M. thrascoleptum. The latter is known only from a single collection from Ivory Coast, West Africa. Comparing M. dentatumwith M. sersalatum, the scape index is similar but M. dentatumis smaller, TL 1.63 mm or less, versus TL 2.0-2.2 mm; the metanotal groove in M. dentatumis distinctly U-shaped whereas in M. sersalatumit has a sharply defined V-shape; in M. sersalatumthe erect hairs on the body are shorter (Bolton 1987). The Monomoriumfossulatum-group contains seven species, widely distributed in tropical Africa (bolton 1987) and two species, M. fossulatum Emeryand M. australicum Forel, which are widespread in the Indo-Australian region and on the islands of the Pacific and Indian Oceans (Wilson & Taylor 1967).  The new species has been collected from different localities in Egypt (Damietta, ElMinyia, Qalyubiya and Port Said) and represents the first record of the fossulatum-group from Egypt and the Palaearctic region. It seems likely that M. dentatum sp. n.has a wide distribution inside Egypt especially in the Nile river valley because specimens collected from Damietta, Abu-Swelem (El-Minyia) and Abuzabal (Qalyubiya) are all rather close to the river with the exception of the single specimen collected from Port Said.  Derivatio nominis. The species name is based on the dentate propodeum and was proposed by Cedric A. Collingwood.  Ecological observations. One type series, including the holotype, was found nesting under a rock in a small village 3 km from El-Minyia city (Upper Egypt); there were many Collembola and a single unidentified specimen of the ant genus Pyramica (Trichoscapa) Roger, 1862, living in the same niche. 923892979 2003-08-20 M. R. Sharaf Egypt 31.433332 Damietta 31.8 Holotype 923892976 2003-08-20 M. R. Sharaf Egypt 31.433332 Damietta 31.8 Paratypes 923892977 2003-06-29 M. R. Sharaf Egypt 28.1 El-Minyia, 30.75 Abu-Swelem 923892980 2003-06-21 M. R. Sharaf Egypt 30.05 Qalyubiya 31.25 Abuzabal 923892978 2003-08-26 M. R. Sharaf Egypt 31.266666 Port Said 32.3 923892975 2003-08-20 31.433332 Damietta 31.8