The Ants of Africa
Genus Messor
Microdaceton bernardi (Bernard) Taylor - new status

Microdaceton bernardi (Bernard) Taylor - new status

return to key Type location Guinea (Microdaceton leakeyi, Bernard, 1952: 253, illustrated, worker) worker only known .

{Microdaceton leakeyi}Bernard's description of the workers of "Microdaceton leakeyi Patrizi" (translation).

Worker (previously undescribed). Types: 2 workers from the savanna at Kéoulenta and one labelled "Nimba, Lamotte". The three are identical and are 2.8 mm long without mandibles, 3.25 with.
Here briefly are the principal characters:
Colour brown, petiole and gaster darker (the queen from Kenya [of leakeyi as described by Patrizi in 1947] is dark brown, gaster black, length 4.5 mm), postpetiole clear brown, mandibles yellow-red, clypeus and tarsi clear yellow.
Sculpture very similar to that of exornatum and leakeyi, save for the gaster: that is finely striated longitudinally on the basal quarter, the rest shiny, microscopically puncturated (exornatum is not striated, leakeyi for sure on the basal part, but that is a queen). The large spines, 12 in all, characteristic of the genus, are positioned as with the leakeyi queen (those at the base of the antennae are very short, those on the vertex very close to the posterior angles, the odd posterior spine on the petiole is reduced to a tooth, longer with exornatum. Santschi and Patrizi do not indicate if there is a fine pubescence, without raised hairs. On the other hand, the example marked "Nimba" shows several raised macrochetae, short, truncated, whitish (2 on the head, 4 on the thorax, 4 on the gaster): these hairs have disappeared on the abraded specimens from Kéoulenta.
The author's figures are insufficient for the antennae and the clypeus, such that a comparison is difficult. Here, the clypeus is elongated, incurved towards its centre (see fig.); it seems triangular with leakeyi and oval, not incurved, with exornatum(?). The basal four segments of the funiculus are not equisized, as it appears from the figures, but clearly inequal; the 1st is shorter and more globular than the second, which is equal to the 4th, both being 50% longer than the 3rd. The mandibles are as for the two known species, slender, terminated by three spiniform teeth. One of the forms from Nimba possesses an additional small tooth before the main three on the right mandible. These captures are among the most interesting of Lamotte's collections."

{Microdaceton leakeyi}First, it has to be noted that Bolton saw neither the type worker of exornatum nor the leakeyi queen; so, his description of exornatum is definitive only for variety laevior. Also he makes no reference to Bernard's specimens nor even to his description and illustration. Thus, doubt has to be placed on Bolton's synonymy. Bernard's work predates the description of tibialis by Weber (1952) but if one compares Bernard's description with the two species recognised by Bolton, it is clear that the worker of "leakeyi" cannot be clearly placed with either. [Bolton has good illustrations (1983, Figs. 78, profile of exornatum; 79, full-face head of tibialis; 80-81, petiole, postpetiole and base of first gastral segment in dorsal view for exornatum and tibialis) and descriptive text] Notably the "leakeyi" worker has the prominent teeth on the head shown by exornatum but the latter supposedly is yellow and not dark. Curiously the dorsum of the gaster base is longitudinally striated in Bolton's illustration of exornatum var. laevior, symptomatic of the "leakeyi" worker. There are standing hairs on the gaster of "leakeyi" and not laevior.

As shown by the photomontage, the Bernard species has no hairs on the anterior clypeus or mandible; also the scapes do not reach the lateral protuberance on the head, whereas they surpass the protuberance in the East African exornatum; segments 2-4 of the funiculus are equi-sized, wheras on exornatum the second is about 125% longer than either 3 or 4; the U-shaped impression of the occiput is much deeper in the Bernard species and the propodeal spines are longer.

I can conclude only that, if one accepts the accuracy of both Bernard and Bolton, there are three, if not four, separable species involved and further full revision is required.

I thus have given the Bernard description a new status of species - Microdaceton bernardi (Bernard) Taylor

The photomontage is collated from

© 2007, 2008, 2012 - Brian Taylor CBiol FSB FRES
11, Grazingfield, Wilford, Nottingham, NG11 7FN, U.K.