Tijdschrift voor Entomologie 156 (2013) 57–93 brill.com/tve Revision of the European ants of the Aphaenogaster testaceopilosa-group (Hymenoptera: Formicidae) Peter Boer The taxonomy of the myrmicine ants of the Aphaenogaster testaceopilosa-group is revised. Fourteen species are recognized, including two new species, both from Greece: A. balcanicoides sp. n. and A. karpathica sp. n. Aphaenogaster melitensis Emery, 1924 and A. sporadis Santschi, 1933 are elevated to species level. The following new synonyms are established: Aphaenogaster ionia Santschi, 1933 (= A. balcanica Emery, 1898), A. senilis grata Santschi, 1933 (= A. senilis Mayr, 1853), A. senilis occidua Santschi, 1933 (= A. senilis), A. spinosa etrusca Baroni Urbani, 1969 (= A. spinosa Emery, 1878) and A. corsica Casevitz-Weulersse, 2010 (= A. spinosa). Furthermore, a redescription is given for all European species of the Aphaenogaster testaceopilosa-group. The genus Aphaenogaster now includes 178 species, of which 36 are known from Europe. Identification keys are provided. Keywords: Aphaenogaster, ants, new species, Europe, taxonomy, biogeography. Peter Boer, Department of Terrestrial Zoology, Naturalis Biodiversity Center, PO Box 9517, 2300 RA Leiden, Netherlands. [email protected] Introduction ant species, but excluded the Iberian species. Older The ant genus Aphaenogaster Mayr, 1853 consists of papers dealing with European Aphaenogaster species 178 species, and has a widespread distribution that include the work of Emery (1908) and Santschi encompasses the Neotropical, Nearctic, Palaearc- (1933). tic, Malagascar, Oriental, Indo-Australian and Aus- In this paper a new species group is estab- tralian biogeographic regions (Bolton et al. 2006, lished: the Aphaenogaster testaceopilosa-group, includ- Bolton 2012). In Europe (Palearctic region) the ing fourteen European species. The worker of these genus Aphaenogaster is represented by 36 species, species differ from other species in the genus by a which were previously placed in three subgen- scape which stands well over the occiput, of which era: Aphaenogaster Mayr, 1853, Attomyrma Emery, the second funicular segment is >1.5 longer than 1915a and Ischnomyrmex Mayr, 1861 (Emery 1908, wide, of which the hind tibia is more than eight 1915a). These subgenera are now considered ju- times longer than broad, in having a punctate head nior synonyms (Bolton 1982). Subsequently, Schulz and mesosoma, and having no elongated ‘collar- (1994) divided the Palearctic species belonging to the shaped’ head. The nomenclatural history of the Eu- former subgenus Attomyrma into five species groups. ropean species belonging to the Aphaenogaster tes- In Europe Aphaenogaster is a ‘forgotten’ ant genus. taceopilosa-group is complex. Earlier authors (Emery The taxonomic literature consists almost entirely of 1908, Santschi 1933) used rather variable characters the original descriptions, with one recent paper deal- for the delimitation of species, such as the relative ing with the taxonomy of European Aphaenogaster lengths of the propodeal spines, and the sculpture species (Agosti & Collingwood 1987). They in- and the height of the petiole. Biometrical data, how- cluded Aphaenogaster in their key to the European ever, were not used. This has led to descriptions of Tijdschrift voor Entomologie 156: 57–93, Figs 1–70. [ISSN 0040-7496]. brill.com/tve © Nederlandse Entomologische Vereniging. Published by Koninklijke Brill NV, Leiden. Published 15 July 2013. DOI 10.1163/22119434-00002022 Downloaded from Brill.com09/23/2021 01:09:14PM via free access 58 Tijdschrift voor Entomologie, volume 156, 2013 many varieties, subspecies and species, without argu- PI Petiole Index (Maximum width of peti- mentation and substantial comparison with related ole/maximum width postpetiole) × 100. taxa. PHI Petiole Height Index (Petiole Height A large portion of the taxonomic confusion in this (Fig. 1)/CW) × 100. group centres around three species, namely A. tes- PPPI Petiole Index (petiole width + postpetiole taceopilosa, A. ionia,andA. simonellii. These species width)/CW × 100. have been confused with closely related species. PWI Petiole Width Index (Petiole Width/CW) × The distribution of the A. testaceopilosa-group in 100. Europe corresponds to the area south of the 20° July PSI Propodeal Spine Index (x/y in Fig. 2) × 100. isotherm, roughly equal to that part of Europe influ- PSLWI Propodeal Spine Length-Width Index (x/z enced by the Mediterranean climate, i.e. mild, rainy in Figs 2 and 3) × 100. winters and hot, dry summers. Little is known about RPH Relative Petiole Height (petiole height the biology of these species. Menozzi (1936) and Ba- (Fig. 1)/maximum petiole width) × 100. roni Urbani (1966) published about the biology of RPSI Relative Propodeal Spine length-width In- Aphaenogaster, but it is unclear which species they dex ([x − y]/z in Figs 2 and 3) × 100. discussed. Species of the Aphaenogaster testaceapilosa- SI Scape Index (SL/CW) × 100. group nest in Europe in the soil, mainly under stones SL Maximum straight line scape length exclud- in dry areas. They forage (probably) only during day- ing articular condyle. time. SPD Spine Position in Dorsal view (Fig. 4). This revision is primarily based on the worker SPL Spine Position in Lateral view (Fig. 5). caste. In some cases the species differences between Definition of descriptive terms (modified from males proved more distinct than between workers. Harris 1979): Diagnostic features for males, when available, are Costate. Furnished with longitudinal raised ribs, therefore included in this revision. Images are pro- rounded at their crest. vided for some species and a key is provided for Costulate. A diminutive form of costate, less promi- their identification. Furthermore, a key for the Eu- nently ribbed than costate (Fig. 67 on postpetiole). ropean species groups of the genus Aphaenogaster is Microreticulated. A fine reticulated sculpture, provided, as well as a provisional key for gynes and caused by shallow impressions (visible in magnitude males. 100×) (Fig. 29). Microstriae. Furnished with raised, dense, fine, parallel lineations in wave patterns, often in a Methods and abbreviations fingerprint-like pattern (Figs 8, 9, 67). Europe is defined as the countries within the political Pubescence. Small to minute hair-like cuticular pro- boundaries of Europe, including the European part jections that are not socketed basally (Bolton 1994). of Turkey, but excluding the Canary Islands and Punctate. Set with fine, impressed points or punc- Cyprus. Subspecies, varieties and synonymized taxa tures, appearing as pinpricks (Fig. 29). of species treated in this paper, but not part of the Rugae.WrinklesasinMyrmica species. European fauna, are excluded. Ruguloreticulated. Longitudinal rugulae connected Size and shape characters are quantified and are with transverse rugulae (Figs 28, 34) reported as lengths or indices. All measurements are Rugulose. Minutely wrinkled (Fig. 70). in millimetres. Measurements were carried out with Scabriculous. With fine and regular short rugulae in a Leica Wild M3B and a Carl Zeiss Jena stereo different directions (Fig. 31). microscope at various magnifications, and a Schott Seta. Any stout hair socketed basally, plural: setae CL 1500LCD cold light source. The measurements (Bolton 1994). and indices taken are defined below. Shine. In order of matt to shiny: matt, matt satin, Explanation of numeric characters and abbrevia- satin, shiny satin, wax glossy, glossy (= subdued tions used in the text: shine), shiny (seen in diffuse light). CI Cephalic Index (CW/CL) × 100. Specimens examined in this study are deposited in CL Maximum cephalic length in median line. the following institutions and private collections: CW Maximum cephalic width, across eyes. CGB Collection Gregor Bracko,ˇ Ljubljana, Slo- EYI Eye Index (Maximum eye diameter/CL) × venia 100. CG Collection Gielen, Antwerp, Belgium FTI Femur Tibia Index (length F3/length T3) × CM Collection Maassen, Echt, Netherlands 100. CPB Collection Peter Boer, Bergen NH, Neth- OCI (Outer distance between the upper ocelli/ erlands cephalic width just above the eyes) × 100. Downloaded from Brill.com09/23/2021 01:09:14PM via free access Boer: Revision of the Aphaenogaster testaceopilosa-group 59 Figs 1–9. Aphaenogaster features. 1. Petiole height. 2. Propodeal spine length (x) and index (PSI: x : y). 3. Distance between the propodeal spines. 4. Positions of propodeal spine in dorsal view. 5. Positions of propodeal spine in lateral view. 6. Head of small worker. 7. Head of large worker. 6–7 after Emery (1908). 8. Microstriae: transverse near base. 9. Microstriae: longitudinal. 8–9 after Cagniant (1996). IRSNB Institut Royal des Sciences Naturelles de ZMAN Naturalis Biodiversity Center, Leiden, Belgique, Brussels, Belgium Netherlands (former collections Zoolo- MNHN Muséum National d’Histoire Naturelle, gisch Museum Amsterdam) Paris, France MNLB Museum für Naturkunde Leibniz-Insti- tut für Evolution- und Biodiversitätsfor- Discussion of character variations schung, Berlin, Germany The variation between specimens of different local- MSNG Museo Civico di Storia Naturale, Genova, ities often results in taxonomic difficulties and can Italy: Collection Emery lead to discussions about distinguishing varieties, MSNV Museo Civico di Storia Naturale, Verona, subspecies and/or species. This is also the case within Italy: Collection Baroni Urbani the A. testaceopilosa-group (e.g. Forel 1911, Emery NHMB Naturhistorisches Museum, Basel, Switzer- 1915a, Menozzi 1936, Baroni