Conflicting patterns of DNA barcoding and taxonomy in the cicada genus Tettigettalna from southern Europe (Hemiptera: Cicadidae)

Abstract

DNA barcodes have great potential to assist in species identification, especially when high taxonomical expertise is required. We investigated the utility of the 5' mitochondrial cytochrome c oxidase I (COI) region to discriminate between 13 European cicada species. These included all nine species currently recognized under the genus Tettigettalna, from which seven are endemic to the southern Iberian Peninsula. These cicadas have species-specific male calling songs but are morphologically very similar. Mean COI divergence between congeners ranged from 0.4% to 10.6%, but this gene was proven insufficient to determine species limits within genus Tettigettalna because a barcoding gap was absent for several of its species, that is, the highest intraspecific distance exceeded the lowest interspecific distance. The genetic data conflicted with current taxonomic classification for T. argentata and T. mariae. Neighbour-joining and Bayesian analyses revealed that T. argentata is geographically structured (clades North and South) and might constitute a species complex together with T. aneabi and T. mariae. The latter diverges very little from the southern clade of T. argentata and shares with it its most common haplotype. T. mariae is often in sympatry with T. argentata but it remains unclear whether introgression or incomplete lineage sorting may be responsible for the sharing of haplotypes. T. helianthemi and T. defauti also show high intraspecific variation that might signal hidden cryptic diversity. These taxonomic conflicts must be re-evaluated with further studies using additional genes and extensive morphological and acoustic analyses.

Tettigettalna josei (Boulard, 1982) (Hemiptera: Cicadoidea): first record in Spain, with notes on the distribution, genetic variation and behaviour of the species

“…These values are in general agreement with the ones previously reported for Tettigettalna josei (Boulard 1982). Sequences of cytochrome c oxidase I (COI) obtained from the three specimens collected in Spain (GenBank: KF977503–KF977505) were identical to the ones reported in Nunes et al (2014) for Tettigettalna josei (GenBank: KC807267–KC807274) thus confirming species identification.…”

“…Sequences of 581 base pairs from the 5’ region of the cytochrome c oxidase I (COI) mitochondrial gene were obtained from 15 males of Tettigettalna josei . Sequences were obtained as described in Nunes et al (2014) and deposited in GenBank (accession numbers KF977491–KF977505). A minimum spanning network was constructed with the median-joining method (Bandelt et al 1999) in NETWORK 4.6.1.1 (http://www.fluxus-engineering.com).…”

“…We combined COI sequences from Nunes et al (2014) and from this study in a dataset composed by 23 male specimens of Tettigettalna josei from several locations across its distribution (Table 4) and constructed a minimum spanning network (Fig. 5a).…”

Complex within a Complex: Integrative Taxonomy Reveals Hidden Diversity in Cicadetta brevipennis (Hemiptera: Cicadidae) and Unexpected Relationships with a Song Divergent Relative

“…[27,31,32,80]). Cicada complexes with morphologically similar but acoustically different species have repeatedly been shown to exhibit irregular mtDNA phylogenies [32,68,81,82]. …”

Molecular species delimitation methods recover most song‐delimited cicada species in the European Cicadetta montana complex

“…The study group Cicadas (Hemiptera: Cicadidae) are a widespread insect family found on every continent except Antarctica. The continued discovery of new species and collection of new specimens of these insects for acoustic, morphological and molecular analyses is important for understanding cicada evolution and for conservation (Gogala & Trilar, 2004;Moulds, 2005;Quartau & Simões, 2006;Gogala et al, 2008a;Marshall et al, , 2011Puissant & Sueur, 2010;Gogala et al, 2012;Popple, 2013;Nunes et al, 2014;Hertach et al, 2015). Song characters are especially powerful for species delimitation.…”