Simopone schoutedeni

Bolton, Barry & Fisher, Brian L., 2012, Taxonomy of the cerapachyine ant genera Simopone Forel, Vicinopone gen. n. and Tanipone gen. n. (Hymenoptera: Formicidae) 3283, Zootaxa 3283 (1), pp. 1-101 : 14-15

Characters of schoutedeni species group (workers)

1 Palp formula 6,4 ( annettae , brunnea , dryas , miniflava, wilburi ).

2 Mandibles unsculptured, smooth with scattered small pits.

3 With head in profile the parafrontal ridge reaches, or almost reaches, the anterior margin of the eye (i.e. it is not confined to the area immediately behind the clypeus).

4 Eyes with numerous short but conspicuous setae that arise between the ommatidia.

5 A distinct, impressed transverse sulcus is present on the mesopleuron that conspicuously divides the sclerite into an upper anepisternum and a lower katepisternum; this sulcus is continuous posteriorly with the sulcus that separates the mesopleuron from the metapleuron.

6 Promesonotal suture is represented across the dorsum by a line of minute cuticular ribs or a line of adjacent punctures; line of suture is conspicuous to faint. Metanotal groove is at most a very faint, almost effaced line, but usually is entirely absent.

7 Propodeal spiracle circular or very nearly so.

8 Anteroventral process of AII (petiole) in profile consists of a short lamina that has a roughly oval fenestra near its midlength; the posteroventral corner of the process is dentiform or short-spiniform.

9 Pygidium with a small, insignificant apical fork of two or four teeth that are usually only slightly larger than the other marginal denticles.

10 Generally relatively small species, worker HW 0.46–0.80.

In addition, all examined specimens of this group, except for a couple of workers of wilburi , have a small patch of pale, thin cuticle on the side of the pronotum. The patch is roughly oval to crudely elongate-triangular and is located on the anterior half of the sclerite, usually just below its mid-height. No trace of this patch occurs in any species of the grandidieri group that has been seen. Most members of the emeryi group have no equivalent of this patch, but something that may be similar can be seen in grandis , and some specimens of Malagasy species have a reddish spot on the cuticle in a similar position, but this seems variable within species.

Each of the eleven species assigned to this Afrotropical endemic group is represented by very few specimens; in several cases only single specimens are known. This tends to make the assessment of species limits rather difficult, because normal variations in sculpture, shapes of particular body parts, size-related variation, and so on are impossible to assess. However, in wilburi 12 specimens, including a queen, are known from five different localities, the longest series of which contains six workers. In this series some size-variation is apparent, but the morphology remains consistent. Similarly, the five workers known of annettae , from four localities, are also quite uniform. These consistencies, compared and contrasted to the different morphological modifications seen in other specimens, are taken as the template by which the species-rank taxonomy of the group is currently arranged. It may be that some of the species currently represented only by singletons will eventually be found to show size-related variation, so the taxonomy will need re-assessment when longer series, and particularly nest-series, have been accumulated.