Molecular and Morphological Inference of Three Cryptic Species within the Merodon aureus Species Group (Diptera: Syrphidae)

Abstract

The Merodon aureus species group (Diptera: Syrphidae: Eristalinae) comprises a number of different sub-groups and species complexes. In this study we focus on resolving the taxonomic status of the entity previously identified as M. cinereus B, here identified as M. atratus species complex. We used an integrative approach based on morphological descriptions, combined with supporting characters that were obtained from molecular analyses of the mitochondrial cytochrome c oxidase I gene as well as from geometric morphometry of wing and surstylus shapes and environmental niche comparisons. All applied data and methods distinguished and supported three morphologically cryptic species: M. atratus stat. nov., M. virgatus sp. nov. and M. balkanicus sp. nov., which constitute the M. atratus species complex. We present an identification key for the sub-groups and species complexes of the M. aureus species group occurring in Europe, describe the taxa and discuss the utility of the applied methods for species delimitation. The estimated divergence times for the species splits of these taxa coincide with the Pleistocene Günz-Mindel interglaciation and the Great interglaciation (between the Ris and Mindel glacial periods).

Taxonomic review of the Palaearctic species of the Cheilosia caerulescens-group (Diptera, Syrphidae)

“…Identical or near identical COI barcodes of closely related Eristalinae species has also been recorded for Merodon species groups, see e.g. Šašić et al (2016).…”

Cryptic speciation in theMerodon luteomaculatuscomplex (Diptera: Syrphidae) from the eastern Mediterranean

“…It became the most species‐rich hoverfly genus in Europe (121 spp.) after the appearance of recent publications with newly described species (Ačanski et al., ; Šašić et al., ; Veselić et al., ). This phytophagous genus is especially widespread in the Mediterranean Basin, a region with a high diversity of geophytes.…”

“…The most comprehensive taxonomic study of this genus is that of Hurkmans () who revised 61 Palaearctic species. During the last 15 years, multiple authors have significantly contributed to clarifying the taxonomy and distribution of the taxa of this speciose genus, focusing on particular species groups on the Iberian, Balkan, and Anatolian peninsulas (e.g., Ačanski et al., ; Marcos‐García, Vujić, & Mengual, ; Popov, ; Popović et al., ; Radenković et al., ; Šašić et al., ; Ståhls et al., ; Veselić, Vujić, & Radenković, ; Vujić, Marcos‐García, Sarıbıyık, & Ricarte, ; Vujić, Radenković, Likov, Trifunov, & Nikolić, ; Vujić et al., , ). It became the most species‐rich hoverfly genus in Europe (121 spp.)…”

“…The shape of the male genitalia in this group is simple and very similar in all species of the group. Its members can be easily recognized by their small size, rounded abdomen, and the presence of a spike on the metatrochanter of males (Radenković et al., ; Šašić et al., ; Veselić et al., ). This group is characterized by high endemism (e.g., on the Iberian Peninsula, more than 70% of species from the aureus group are endemic to the region) and the presence of morphologically cryptic species.…”

Revision of the Palaearctic species of the Merodon desuturinus group (Diptera, Syrphidae)

“…In the last decade, a number of papers have been published on particular species groups, such as aureus , melanocerus , nanus , natans , nigritarsis , ruficornis (Milankov et al 2008a, Francuski et al 2009, 2011, Vujić et al 2012, 2013, 2015, Šašić et al 2016, Radenković et al, 2018). The Mediterranean fauna has been frequently studied (Mengual et al 2006, Marcos-García et al 2007, 2011, Petanidou et al 2011, Radenković et al 2011, Ricarte et al 2012, Ståhls et al 2009, 2016, Vujić et al 2007, 2011), whereas the Afrotropical Region with less than ten recognised species (Pape and Thompson 2013), has received less attention (Radenković et al 2018).…”