Unexpected levels of cryptic diversity in European bees of the genus Andrena subgenus Taeniandrena (Hymenoptera, Andrenidae): implications for conservation

Abstract

Using a combination of DNA barcodes and morphology, we examine species boundaries in bees of the genus Andrena subgenus Taeniandrena in Europe. First, we solve the long controversy surrounding the status of Andrena ovatula (Kirby, 1802) and A. albofasciata Thomson, 1870, proposed to represent distinct species nearly 100 years ago, but mostly treated as conspecific in recent studies. Our results unambiguously support the presence of two taxa that are often found in sympatry: the first taxon, referred to as A. ovatula, is present in Northern Europe but also in Southern Europe along the Mediterranean coast; the second taxon is referred to as A. afzeliella (Kirby, 1802), stat. rev., with A. albofasciata considered to be a junior synonym (syn. nov.), and is widely distributed in Europe. Second, we show that another widely distributed species has hitherto been overlooked in Europe: A. ovata Schenck, 1853, stat. rev. Third, we demonstrate that two taxa currently treated as subspecies should be given specific rank due to significant morphological and genetic differences: A. croceiventris Morawitz, 1871, stat. rev., so far treated as a subspecies of A. similis Smith, 1849, and A. vocifera Warncke, 1975, stat. nov., so far treated as a subspecies of A. gelriae van der Vecht, 1927. Both A. croceiventris and A. vocifera have particularly restricted ranges in Europe, being known only from central to southern Italy and Sicily, and continental France, respectively. Fourth, we describe a new species from Sardinia and Corsica, A. antonellaesp. nov. Lastly, the following new synonymies are proposed: A. similis, A. ocreata cyprisina Warncke, 1975 and A. similis caraimica Osytshnjuk, 1994 are placed in synonymy with A. russula Lepeletier, 1841 (syn. nov.); A. fuscata (Kirby, 1802), A. canescens Schenck, 1853 and A. pseudovatula Alfken, 1926 are placed in synonymy with A. afzeliella (syn. nov.). Lectotypes are designated for A. afzeliella, A. fuscata (Kirby, 1802), A. ovata and A. wilkella (Kirby, 1802). Our results suggest a particularly fast diversification in this group of bees, leading to the presence of numerous species exhibiting particularly restricted geographic ranges. We discuss the implications for conservation of this astonishing cryptic diversity in European bees.

Double-blind validation of alternative wild bee identification techniques: DNA metabarcoding and in vivo determination in the field

“…These results are in agreement with recent analyses that have resolved the controversy by consistently demonstrating the existence of two distinct species within the complex, A. ovatula and A. afzeliella (Kirby, 1802) (=A. albofasciata), based on molecular, morphological and ecological evidence (Praz et al 2022). Therefore, the nomenclature of DNA barcodes currently available in BOLD should be updated accordingly to match this new taxonomic consensus, further improving the detection capacity of molecular approaches.…”

“…Incongruence between DNA and both PIN experts can partially be explained by unclear species delimitation. There is a historical controversy regarding whether Andrena ovatula and Andrena albofasciata should be consider as one or two species (Westrich et al 2011;Schmidt et al 2015;Praz et al 2022). In our study, the metabarcoding pipeline supported the presence of A. albofasciata against A. ovatula in S4 and S10, in opposition to the morphological analysis, but was in agreement with both PIN experts regarding detecting only A. ovatula in S5.…”

A revision of the Andrena (Hymenoptera: Andrenidae) fauna of Iran, with the description of 16 new species

“…The subgenus Taeniandrena is taxonomically complex and contains many cryptic species. It has recently undergone a substantial revision (Praz et al 2022), with many changes for the West Palearctic fauna, including the recognition of A. afzeliella as a distinct taxon and the senior name of A. albofasciata Thomson, 1870.…”

“…Confused due to historical synonymy with A. ovatula. Across Europe to Turkey, the Levant, and Iran (Praz et al 2022). Material examined Alfken (1927, locus typicus).…”

“…April is very early for this taxon, which in Europe typically flies in June and July. Given the extreme taxonomic challenge associated with the morphological identification of members of the subgenus Taeniandrena (Praz et al 2022), and given that several taxa found in eastern Turkey were described after the capture of this specimen (e.g., A. producta Warncke, 1973, A. hova Warncke, 1975, A. solitaria Warncke, 1975, this taxon cannot be confirmed from Iran until male specimens with their distinctive genital capsule have been examined. Warncke, 1965 Literature records Allahverdi et al (2016).…”