Dorylus gribodoi

Dorylus gribodoi is a West African species of army ants in the genus Dorylus.
== Description ==
The diagnostic features of the D. gribodoi male are its mandible shape (the anterior quarter notably flexed inward) and the nearly flat posterior head margin. In the original description Emery compared D. gribodoi with D. atratus and stated that D. atratus was darker than D. gribodoi and that its scape was longer than half the length of the funiculus. Both Smith (1859) in the original description and later Santschi (1914) mentioned that the posterior head margin of the D. atratus male was convex. While the colouration of D. gribodoi is variable, it is not uniformly black in any of the specimens examined by us and the head shape is nearly rectangular with a flat posterior margin. Workers of D. gribodoi are unique (and easily identifiable) among all Dorylus species in having a nearly round petiole in dorsal view and a distinct ridge on the posterior head margin that is laterally developed into tiny horns in larger specimens. D. gribodoi workers of the same size class can be separated from workers of the D. kohli / D. congolensis complex also by the posterior margin of the head being angular in lateral view and not smoothly rounded.
Larger D. emeryi workers can be separated from D. gribodoi workers of the same size class by the following features: posterior angles of head drawn out backwards and ventrally, petiole in dorsal view angled at widest point, petiole has several conspicuous erect setae on dorsal surface (which are lacking in D. gribodoi), largest workers have massive heads with width ≤ 3.92 mm. The unique petiole shape of D. gribodoi was recognized by Emery in his original description of D. gerstaeckeri (Emery 1895) and also by Bernard (1952) who described D. lamottei based on workers collected at Mount Nimba in Guinea but failed to realize that these specimens were in fact conspecific with Emery’s D. gerstaeckeri. Bernard (1953) also identified males taken from the same location as D. gribodoi, but the association between these males and his D. lamottei workers necessarily remained unknown to him.
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