Hypoponera species groups

The following reports on Afrotropical and West Palaearctic Hypoponera species groups as reported by: Bolton, B. & Fisher, B.L. 2011. Taxonomy of Afrotropical and West Palaearctic ants of the ponerine genus Hypoponera Santschi. Zootaxa 2843: 1-118.

The groups are based on worker morphology and excludes Hypoponera species that do not occur in two areas that were the focus of this regional revision. These groups may thus, as Bolton and Fisher make clear, "prove to be inaccurate or artificial on a world-wide basis."

The Hypoponera genus page.

Key to Afrotropical and West Palaearctic Hypoponera

Key to West Palaearctic Hypoponera

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 * With mesosoma in dorsal view the metanotal groove is absent or at most vestigially represented by a slight concavity, change of slope, or faint transverse line that does not interrupt the surface . . . . . abeillei group


 * With mesosoma in dorsal view the metanotal groove is conspicuous and strongly developed as a distinct transverse groove that clearly interrupts the surface . . . . . 2

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 * Base of cinctus of second gastral tergite (Abd. IV) strongly cross-ribbed . . . . . boerorum group


 * Base of cinctus of second gastral tergite (Abd. IV) smooth, without cross-ribs . . . . . 3

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 * Petiole squamiform. Mesonotal-mesopleural suture present. Maximum width of first gastral tergite in dorsal view equal to or slightly greater than width of second tergite at its midlength . . . . . dulcis group


 * Petiole short-nodiform. Mesonotal-mesopleural suture absent. Maximum width of first gastral tergite in dorsal view less than width of second tergite at its midlength . . . . . punctatissima group

Hypoponera abeillei group
Species with the following combination of characters in the worker caste.

1 Metanotal groove vestigial to absent across dorsum of mesosoma; at most represented by a vague depression, slight change of slope or a simple line, never a strongly defined deep groove that conspicuously interrupts the surface.

2 Mesonotal-mesopleural suture feeble to absent.

3 Petiole node never squamiform.

4 Eyes absent, or a dark spot, or a single small, inconspicuous ommatidium; only uncommonly with several ommatidia.

5 Anterior clypeal margin lacks a median indentation or notch.

This large group, by far the largest in Africa, falls into two main sections, each of which contains a number of closely related species complexes.

Section 1 contains those species in which the disc of the second gastral tergite is microreticulate or has superficial punctures that are so closely packed that their margins are confluent or nearly so; and which have the maximum width of the first gastral tergite in dorsal view less than the width of the second tergite at its midlength. The latter is because the sides of the second tergite, in dorsal view, tend to be convex. This section, which contains Hypoponera abeillei itself, breaks down into four Afrotropical complexes of related species. In the first complex (Hypoponera lepida and Hypoponera obtunsa), the base of the cinctus of the second gastral tergite is smooth, without cross-ribs. In the other complexes cross-ribs are conspicuous. The second complex contains only Hypoponera angustata, a minute species in which the funiculus has only the four apical segments distinctly enlarged; in all other species there are usually obviously five, and sometimes vaguely six, gradually incrassate segments apically. The third complex contains Hypoponera austra, Hypoponera exigua, Hypoponera natalensis and Hypoponera traegaordhi, characterised by the possession of a transverse groove or impression, which has a conspicuous dorsal margin, on the posterior face of the petiole node above the posterior peduncle. The final complex is artificial and contains all the remaining species of the section that lack the specialisations just mentioned (Hypoponera blanda, Hypoponera bulawayensis, Hypoponera camerunensis, Hypoponera coeca, Hypoponera defessa, Hypoponera fatiga, Hypoponera juxta, Hypoponera hawkesi, Hypoponera inaudax, Hypoponera lassa, Hypoponera meridia, Hypoponera orba, Hypoponera pulchra, Hypoponera regis, Hypoponera rigida, Hypoponera perparva).

Section 2 contains those species that have the disc of the second gastral tergite with sharply incised punctures that are widely separated by areas of smooth, shining cuticle; and the maximum width of the first gastral tergite in dorsal view is equal to or greater than the width of the second tergite at its midlength, because the sides of the second tergite, in dorsal view, tend to be straight or even slightly concave. This section falls into three complexes. In the first (Hypoponera faex, Hypoponera hebes, Hypoponera jeanneli, Hypoponera jocosa, Hypoponera mixta, Hypoponera quaestio, Hypoponera surda, Hypoponera tecta, Hypoponera ursa) the posterior surface of the petiole node has a radiating series of short cuticular ridges just above the posterior peduncle, and the base of the cinctus of the second gastral tergite has cross-ribs present. In the second complex (Hypoponera dema, Hypoponera molesta, Hypoponera segnis, Hypoponera tristis, Hypoponera venusta) cuticular ridges are absent from the posterior face of the petiole node but the cinctus of the second gastral tergite retains cross-ribs. The final complex (Hypoponera aprora, Hypoponera comis, Hypoponera dis, Hypoponera importuna, Hypoponera occidentalis, Hypoponera odiosa, Hypoponera producta) lacks ridges on the posterior face of the petiole node and also lacks cross-ribs at the base of the cinctus of the second gastral tergite so that the base of the cinctus is smooth and shining.

Hypoponera dulcis group
Species with the following combination of characters in the worker caste.

1 Metanotal groove present and strongly developed across dorsum of mesosoma; always a strongly defined deep groove that conspicuously interrupts the surface.

2 Mesonotal-mesopleural suture present.

3 Petiole node squamiform.

4 Eyes present, small but always distinct.

5 Maximum width of first gastral tergite in dorsal view is equal to or slightly less than the width of the second tergite at its midlength.

6 Cinctus of second gastral tergite smooth, without cross-ribs at its base.

7 Anterior clypeal margin lacks a median indentation or notch.

Only a single species of this group, Hypoponera dulcis, occurs in sub-Saharan Africa, where it is extremely common and very widespread; in fact it is the most common and most abundant Afrotropical Hypoponera species. A scan of the rest of the world’s fauna indicates that there are abundant species in the Oriental, Malesian, Austral and Neotropical regions that apparently belong in the same group as dulcis. Given the abundance of this group elsewhere and the presence of only a single species in the Afrotropical region, the possibility that dulcis may represent an ancient but very successful invasion from outside the region must be considered.

Hypoponera punctatissima group
Species with the following combination of characters in the worker caste.

1 Metanotal groove present and strongly developed across dorsum of mesosoma; always a strongly defined deep groove that conspicuously interrupts the surface.

2 Mesonotal-mesopleural suture vestigial to absent.

3 Petiole node not squamiform.

4 Eyes present, small but always distinct and located very far forward on the side of the head.

5 Maximum width of first gastral tergite in dorsal view is distinctly less than the width of the second tergite at its midlength.

6 Cinctus of second gastral tergite smooth, without cross-ribs at its base.

7 Anterior clypeal margin lacks a median indentation or notch.

Three species of this group occur in both sub-Saharan Africa and the West Palaearctic, Hypoponera eduardi, Hypoponera punctatissima and Hypoponera ragusai. Another, Hypoponera nivariana, is restricted to the Canary Islands and a fifth species, Hypoponera sinuosa, has so far been found only in Guinea. There are several more nominal taxa in other regions. H. punctatissima is without doubt the most successful ponerine tramp species in the world, and both eduardi and ragusai also have recognised tramping ability.

Hypoponera boerorum group
Species with the following combination of characters in the worker caste.

1 Metanotal groove present across dorsum of mesosoma.

2 Petiole node not squamiform.

3 Eyes usually present, rarely absent.

4 Maximum width of first gastral tergite in dorsal view is about the same as the width of the second tergite at its midlength.

5 Cinctus of second gastral tergite with strong cross-ribs.

6 Anterior clypeal margin lacks a median indentation or notch.

Five southern African species are included here (Hypoponera boerorum, Hypoponera ignavia, Hypoponera spei, Hypoponera sulcatinasis, Hypoponera transvaalensis). The group may be artificial as it basically represents species that are similar to the abeillei group but which retain a strongly developed metanotal groove.