Pyramica baudueri

First record of Pyramica baudueri (Emery, 1875) (Hymenoptera: Formicidae) from Bulgaria

Pavel Bezděčka & Klára Bezděčková

Abstract

The first record of Pyramica baudueri (Emery, 1875) from Bulgaria is reported. It also represents the discovery of a genus and tribe of ants unknown from Bulgaria until now. One worker of P. baudueri was found in South-eastern Bulgaria, near the village of Shiroko Pole. The known distribution of P. baudueri in the Palaearctic region is summarised and discussed.

Key words: Ants, first record, Pyramica baudueri, Dacetini, Formicidae, Bulgaria.

Introduction

The Bulgarian myrmecofauna is insufficiently explored. In particular, some sub-Mediterranean species, parasitic species and species with cryptic lifestyle known from South-eastern Europe have not been reported from Bulgaria until now. In recent years several new records of ant species were reported for Bulgaria (see, e.g., Radchenko & Antonova 2004, Stankiewicz & Antonova 2005, Steiner & al. 2005, Antonova 2008), but the last published checklist of Bulgarian ants (Atanassov & Dlussky 1992) has not been updated yet.

Here we report the discovery of the sub-Mediterranean species Pyramica baudueri (Emery, 1875), a species with cryptic lifestyle, found by P. Bezdecka in South-eastern Bulgaria.

Results

The recent species-level redetermination of ants deposited in the Museum of South-eastern Moravia (the Czech Republic, Zlin) resulted in the identification of one worker of Pyramica baudueri (Emery, 1875). The redetermination of this specimen was done using the keys in Herve (1969), Agosti & Collingwood (1987) and Bolton (2000). The worker was collected in a place called Zhelezni vrata (41° 37' 06" N, 25° 28' 00" E, ca. 320 m a.s.l., South-eastern Bulgaria, Fig. 1) on 26.IV.1986 (leg. et det. P. Bezdecka). This forest-steppe locality lies two kilometres south of the centre of the village of Shiroko Pole. The specimen was found under a big stone on the soil surface. In spite of intensive exploration of the locality neither a nest nor further individuals were discovered.

Discussion

Pyramica Roger, 1862 is the second largest genus of the tribe Dacetini with 349 recent species (Yusupov 2009). Only five Pyramica species occur in the Western Palaearctic region: P. argiola (Emery, 1869), P. baudueri, P. membranifera (Emery, 1869), P. tenuipilis (Emery, 1915) and P. tenuissima (Brown, 1953). The known distribution of P. baudueri covers the Channel Islands (Radchenko 2007), Morocco (Bolton 2000), continental Spain (Espadaler 1997, Bolton 2000, Radchenko 2007), the Balearic Islands(Espadaler 1997), Tunisia (Bolton 2000), Malta (Radchenko 2007), continental France (Bolton 2000, Radchenko 2007), Corsica (Bolton 2000), Sardinia (Bolton2000, Radchenko 2007), Sicily (Radchenko 2007), continental Italy (Bolton 2000, Radchenko 2007), Switzerland(Baroni Urbani 1998, Bolton 2000, Braschler 2002), Hungary (Galle & al. 1998), Romania (Marko 2008), Croatia (Bracko 2006), Macedonia (Radchenko 2007), Montenegro (Petrov 2006), Greece (Agosti & Collingwood 1987, Radchenko 2007), Turkey (Bolton 2000, Radchenko 2007), and Armenia (Arakelyan 1994).

Pyramica baudueri is exclusively a predator, hunting especially Collembola but occasionally also other small arthropods (Marko 2008). It lives and forages in the soil, inhabiting sun-exposed and warm sites (Braschler 2002, Marko 2008). Colonies are usually small and monogynous(Bolton 2000). Specimens of genus Pyramica can be identified as members of the tribe Dacetini immediately in the field, due to the characteristic shape of the head. A recent, detailed characterisation of workers of P. baudueri is given by Marko (2008).

The worker of Pyramica baudueri reported here was found by hand collecting. The discovery represents the finding of a species, genus and tribe of ants hitherto unknown from Bulgaria. The hidden lifestyle of Pyramica ants and the hitherto lack of applying more specific collecting methods are probably the main reasons for the absence of any further data on this species from Bulgaria.

Recently, dacetine ants have been recorded more frequently in other parts of Europe, by using quantitative methods of collection. Braschler (2002) caught two workers of P. baudueri by pitfall trapping in Switzerland. DevAn (2008) captured the only specimen of the genus Pyramica known from Slovakia (male of P. cf. argiola) in a Moericky trap (yellow dish with salt solution). Fellner & al. (2009) repeatedly detected P. argiola in Austria using the Winkler sifting and extracting method, a collection technique commonly used in tropical rainforests. The latter two instances indicate that the application of a greater variety of collection techniques may boost European ant faunistics.