Key to Mediterranean Aphaenogaster graeca complex

This worker key is based on: Bračko, G., Lapeva-Gjonova, A., Salata, S., Borowiec, L., Polak, S. 2019. Aphaenogaster illyrica, a new species from the mountains of the Balkan Peninsula (Hymenoptera, Formicidae). ZooKeys 862: 89–107 (DOI 10.3897/zookeys.862.32946).

Notes preceding the key: Recently published papers (Borowiec and Salata 2017, Alicata and Schifani 2019) indicate that the A. subterranea group is very diverse and comprise several undescribed taxa. The Balkans appears to be the most species-rich region and is in need of further investigation. Results presented in this publication are a preliminary attempt to systematise our knowledge about this group, and Aphaenogaster illyrica and A. graeca compose a distinct complex within the A. subterranea group. Because the A. subterranea group consists of mixture of species of uncertain taxonomic status and several undescribed morphotaxa, we can provide only a generic key to the subterranea group with features focused on the graeca complex.

1

Metanotal groove absent or very shallow (Maghreb, Canary Islands, Siculo- Maltese archipelago, Southern Italy) . . . . . Aphaenogaster crocea group, sensu Alicata and Schifani (2019)

Metanotal groove present, deep and narrow (Mediterranean Region) . . . . . 2

2

return to couplet #1

Pronotum and mesonotum form regular convexity, mesonotum not raised above the surface of pronotum, propodeal spines short, not longer than half length of the first segment of antennal funiculus, mesosoma short . . . . . Aphaenogaster subterranea complex

Mesonotum clearly raised above the surface of pronotum, propodeal spines long and thin, as long as or longer than 0.7 length of the first segment of funiculus, mesosoma elongated . . . . . 3

3

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Base of the first gaster tergite with distinct rugae, body brown to dark brown, head distinctly darker than mesosoma, head sculpture strong, posterior part of head dorsum with sculpture only slightly reduced but still distinct, lateral surface of propodeum, at least partly, with strong longitudinal rugae . . . . . Aphaenogaster graeca

Base of the first gaster tergite smooth, body uniformly yellowish-brown to rusty-brown, head sculpture weaker, posterior part of head dorsum with sculpture at least partly reduced, lateral surface of propodeum smooth or with few gentle longitudinal rugae . . . . . Aphaenogaster illyrica