Pheidole balcanica

Bernhard Seifert, 2016, Inconvenient hyperdiversity - the traditional concept of “ PheIdole pallIdula ” includes four cryptic species (Hymenoptera: Formicidae), Soil Organisms 88 (1), pp. 1-18 : 15

Pheidole balcanica sp.n.

Etymology. The name is given because large parts of the distributional range are in the Balkans.

Type material: See in section 2.2. ‘Type Material’.

Description of the major caste Figs 5–7 . All data of shape variables given in the following description refer to specimens with a cephalic size CS of 1.25 mm.

Medium-sized, on the average larger than Ph. pallidula : CS 1.106–1.457 mm. Head rather short: ratio of maximum median cephalic length against maximum cephalic width 0.90–0.97. Outlines of head in dorsal aspect without linear components: pre- and postocular head sides and occipital corners convex, the hind margin is strongly concavely excavated, depth of excavation 7–12 % of maximum median head length. The eye is the smallest within the Ph. pallidula species complex: ratio of maximum eye diameter against cephalic size 0.118–0.148. Frontal carinae diverging caudad. Anterior half of dorsal head surface longitudinally carinulate caudad to about one eye length posterior of caudal eye margin ( Fig. 5 ). The space between carinulae rather smooth and shining, without conspicuous microsculpture. Posterior half of dorsal head surface smooth and shining. Frontal triangle smooth and shining. Clypeus with exception of a median carinula and several paramedian or lateral ones smooth and shining. Masticatory border of mandibles toothless with the exception of a very strong apical, strong subapical and a weak subbasal dent. Anterior margin of hypostoma with two dents or blunt protrusions. Scape and hind femur short: ratio of scape length against cephalic size 0.55– 0.61 and ratio of hind femur length against cephalic size 0.71–0.79. Whole surface of head, scapes, femora, tibiae, promesonotum, waist and gaster with numerous, thin suberect setae. Mesosoma in lateral view ( Fig. 6 ) with short but sharp and steeply erected propodeal spines, a linear dorsum of propodeum and a well developed metanotal groove. The overall profile of promesonotum is strongly convex and surmounts dorsal propodeum considerably relative to the level of longitudinal mesosomal axis. Outline of promesonotum in dorsolateral (oblique) view without very prominent lobes or protrusions but very flat, obtusely-angled corners – one on dorsolateral pronotum and one or two on dorsolateral mesonotum – are usually visible. Pronotum at small magnifications smooth and shining. Petiole in lateral aspect distinctly longer than high, with a rather straight anterior profile and a small semicircular dorsal crest that appears in dorsal view much wider than long ( Fig. 7 ). Whole surface of head, scape, femora, tibiae, promesonotum, waist and gaster with numerous, thin suberect setae.

Figures

Figure 5. Dorsal aspect of head of the holotype major worker of Pheidole balcanica sp. nov.

Figure 6. lateral aspect of mesosoma of the holotype major worker of Pheidole balcanica sp. nov.

Figure 7. Dorsal aspect of mesosoma of the holotype major worker of Pheidole balcanica sp. nov.