Review of the Merodon natans group with description of a new species, a key to the adults of known species of the natans lineage and first descriptions of some preimaginal stages

Abstract

Merodon natans group (Diptera, Syrphidae) taxa are reviewed using an integrative taxonomic approach combining morphological, morphometric and molecular techniques. The approach substantiates recognition of the three species: M. calcaratus (Fabricius, 1794), M. natans (Fabricius, 1794) and M. pulveris Vujić & Radenković in Radenković et al. 2011, and reveals the existence of a new species, M. makrisi Vujić, Radenković & Tot sp. nov., which is described. It also highlights the existence of a series of natans group populations, especially on some of the Mediterranean islands, in the Levant and in the Afrotropical Region, for which more comprehensive data are required to clarify their status. A key is provided to the natans lineage species currently recognised, and preimaginal stages of some natans-group species are described for the first time. Redescriptions for M. calcaratus and M. natans are provided. A neotype is selected for M. natans. Lectotypes are designated for M. annulatus (Fabricius, 1794) and M. melancholicus (Fabricius, 1794). Merodon annulatus is recognised as a synonym of M. natans.

Characterization of preimaginal developmental stages of two cryptic South African species of the Merodon planifacies complex (Diptera: Syrphidae: Eristalinae: Merodontini), with differentiation through morphometry analysis

“…However, differences between the natans lineage (M. makrisi, M. pulveris and M. natans), the desuturinus lineage (M. capi, M. roni) and the albifrons lineage (M. geniculatus, M. luteihumerus, M. hurkmansi and M. equestris) are not so obvious, as all have a long PRP, that is noticeable from the dorsal view, with the presence of a groove at the base or close to the base. Apparently, the natans lineage presents a PRP that is more like a truncated cone, being wider at the base than at the apex (Vuji c et al, 2021b), while the desuturinus lineage presents a PRP with a similar length and width, and which is rectangular to square in shape. Nevertheless, this difference is very subtle and not even applicable to all the species.…”

“…This is more problematic with phytophagous species because there is very scarce information about which plants the larvae feed on, and this hinders the process of finding larvae to describe (Preradovi c et al, 2018). In the case of the genus Merodon, until now only six species have larval descriptions and only eleven species have had their pupae described (Hodson, 1932;Heiss, 1938;Stuckenberg, 1956;Dixon, 1960;Hartley, 1961;Ricarte et al, 2008Ricarte et al, , 2017Andri c et al, 2014;Preradovi c et al, 2018;Vuji c et al, , 2021b.…”

Integrative taxonomy of the Merodon aberrans (Diptera, Syrphidae) species group: distribution patterns and description of three new species

“…nov. and M. retectus sp. nov), as well as the recent descriptions of new species from the M. aurifer, M. bombiformis and M. natans groups (Vujić et al, 2021b(Vujić et al, , 2021c(Vujić et al, , 2021d, has increased the total number of described Merodon species from 194 (Vujić et al, 2021a) to 202. Future research will additionally increase the total number of Merodon species, confirming once again its status as one of the most species-rich genera of hoverflies.…”

Taxonomic revision of the Merodon tarsatus species group (Diptera, Syrphidae)

“…The highest species diversity of Merodon has been recorded in the Mediterranean region (Vujić et al 2012). In particular, the Iberian Peninsula and Asia Minor (Anatolian Peninsula) are considered centers of Merodon diversity and endemism, as evidenced by the many studies on the Merodon fauna in the Mediterranean (Marcos-García et al 2007;Vujić et al 2007Vujić et al , 2011Vujić et al , 2013Vujić et al , 2015Vujić et al , 2020aVujić et al , 2020bVujić et al , 2020cVujić et al , 2021bVujić et al , 2021cStåhls et al 2009Ståhls et al , 2016Radenković et al 2011Radenković et al , 2020Kaloveloni et al 2015;Ačanski et al 2016Ačanski et al , 2017Likov et al 2020). Some recent publications have also emphasized high Merodon diversity in the Middle East and Central Asia.…”