Integrating vibrational signals, mitochondrial DNA and morphology for species determination in the genus Aphrodes (Hemiptera: Cicadellidae)

Abstract

Reliable delimitation and identification of species is central not only to systematics, but also to studies of biodiversity, ecology and pest management. In the era of Internet‐based biodiversity databases misidentifications are rapidly disseminated and may have far‐reaching consequences. Leafhoppers from the genus Aphrodes (Hemiptera, Cicadellidae) are common and abundant, but, nevertheless, they are still a taxonomically challenging group whose members are often assessed in ecological studies and are also potential vectors of plant diseases. Previous study has shown that the syntype series for A. aestuarina (Edwards) includes also specimens of A. makarovi Zachvatkin and has suggested that misidentifications may be widespread in museum collections. We studied Aphrodes individuals collected from the U.K. and Slovenia in order to provide a more comprehensive analysis of this genus using multiple criteria. Combined work using male and female vibrational signals emitted during courtship, and a 600‐bp fragment within the barcoding region of the COI mtDNA gene, provided validated specimens that we also used for morphometric study. Analyses confirmed A. aestuarina, A. bicincta, A. diminuta and A. makarovi as behaviourally, genetically and morphologically distinct species. Although any of these approaches could be used alone to distinguish between species, combining morphological and molecular approaches will help to improve reliability, especially when identifying females. Morphological investigation of validated individuals from the U.K. and Slovenia also revealed geographic differences within species. By combining several body and aedeagus morphological characters males can be reliably identified, however, morphological differences between species are, nevertheless, relatively small. By contrast, observed genetic distances between Aphrodes species are relatively large (4.2–7.0%). At about half of our collecting sites more than one Aphrodes species was found and A. makarovi was collected together with every other species, including A. aestuarina on tidal saltmarshes. Due to low morphological variation between syntopic congeners it is likely that many museum specimens of Aphrodes have been assigned to the wrong species and species identification in ecological and vector studies may also be questionable.

An integrative approach in the assessment of species delimitation and structure of the Merodon nanus species group (Diptera: Syrphidae)

“…The integrative approach and the use of different sources of information in the identification, delineation, and description of taxa are widely accepted in modern taxonomy (Dayrat 2005;Will et al 2005;Schlick-Steiner et al 2010;Padial et al 2010;Riedel et al 2013;Bluemel et al 2014;Miraldo et al 2014). After 10 years of practice of integrative taxonomy (Goulding and Dayrat 2016), some newly published studies still highlighted the significance of using the holistic approach, e.g., benchmarking results of molecular species delimitation against morphologically well-defined taxa in highly diverse subfamily Drusinae (Insecta, Trichoptera) (Vitecek et al 2017).…”

Male–male interactions and male mating success in the leafhopper Aphrodes makarovi

“…This species is common and widely distributed over the Palearctic and has also been introduced to North America. Aphrodes makarovi is a phloem feeder and found on various host plants and in different habitats, often syntopically with other congeners (Bluemel et al., ). Field populations vary greatly between localities, as well as between years (Derlink et al., ).…”

“…To trigger the appropriate male searching behaviour and to assure a successful location of the female, a male has to detect her reply in the time window immediately after the end of his triggering call (Kuhelj, de Groot, Pajk, et al, 2015). In isolated males, advertisement call is between 14 and 25 s long, while female replies are often longer than male calls and their duration is highly variable (5-60 s) (Bluemel et al, 2014;De Groot et al, 2012).…”

Integrative taxonomy uncovers hidden species diversity in the rheophilic genus Potamometra (Hemiptera: Gerridae)

“…Species are the fundamental biological units, and species delimitation is a central issue in systematics and evolutionary biology (Fujita, Leaché, Burbrink, McGuire, & Moritz, ; May, ; Wiens, ). In recent years, the employment of molecular‐based delimitation methods has made great contributions to the defining of species boundaries, especially in morphologically conserved groups (Bluemel et al, ; Chan et al, ; Devitt, Wright, Cannatella, & Hillis, ; Fujisawa & Barraclough, ; Yang, ). Molecular species delimitation can provide preliminary taxonomic hypotheses and valuable complements to morphological taxonomy (Huang et al, ; Luo, Ling, Ho, & Zhu, ).…”