Congruence between molecular and morphological systematics of Alpine non‐biting midges (Chironomidae, Diamesinae)

Abstract

In mountain regions, climate change is resulting in glacial retreat, causing biodiversity loss in glacial‐fed streams (kryal habitat). Diamesa species (Diptera Chironomidae), the main colonizers of the kryal in the Alps, are the aquatic insects more threatened by extinction. In recent years, DNA barcoding was successfully adopted to delimit species of chironomids and provided species identification. We highlighted that for the Diamesa genus, inconsistencies remain between identification on a morphological and molecular basis, mainly within cinerella and zernyi groups, raising doubts about the validity of head colour as a good diagnostic taxonomic character. Molecular phylogeny reconstruction based on mitochondrial (cytochrome oxidase subunits I and II) and one nuclear (ribosomal 18S rRNA) markers revealed that D. bohemani and D. zernyi on one hand, and D. cinerella and D. tonsa on the other hand, represent populations of the same species. Divergence times suggested that the radiation of these alpine species seems to have been driven by the climatic events with the alternation of glacial periods that happened in the Pliocene and Pleistocene. The initial separation of the oriental species D. steinboecki seems to be due to the tectonic movements of the Periadriatic fault system that probably favoured the emergence of lakes and streams, successively colonized by D. steinboecki. This study raises important concerns, from the validity of diagnostic characters used today to identify larval types up to the uncertainty about how many species of Diamesa inhabit the European Alps and what their fate will be within the scenario of climate change.

Dolichopoda cave crickets from Peloponnese (Orthoptera, Rhaphidophoridae): molecular and morphological investigations reveal four new species for Greece

“…G. Allegrucci et al example, Hernández-Triana et al 2019;Lencioni et al 2021). ABGD analysis confirms these results, grouping the Peloponnesian taxa into seven different groups.…”

Comparative phylogeography of two troglobitic Coleoptera (Leiodidae, Leptodirini) species from Romania based on mitochondrial DNA

“…In conclusion, in both of the analyzed species, P. gracile and P. leptodirum, the genetic divergence of the COI DNA is too low to discriminate between different subspecies, although in some cases a certain degree of intraspecific genetic structure has been found (for example, between the proposed subspecies P. g. bokorianum and P. l. problematicus), suggesting that a reassessment of their status is needed. This result was expected because the genetic divergence at DNA barcoding is not informative about the species status when recently diverged species are compared and complete lineage sorting has not yet been achieved (DeQueiroz 2005; Lencioni et al 2021). Episodes of gene flow between the different proposed subspecies represent a possible explanation preventing complete lineage sorting and most of the populations belonging to the two considered species here are not completely isolated.…”

“…Episodes of gene flow between the different proposed subspecies represent a possible explanation preventing complete lineage sorting and most of the populations belonging to the two considered species here are not completely isolated. Moreover, the identification of species based on one single genetic marker can be incongruent with species identification using morphological characters (Moritz and Cicero 2004;Matz and Nielson 2005;Allegrucci et al 2014;Lencioni et al 2021).…”

Monitoring and conservation of cryophilous biodiversity: concerns when working with insect populations in vanishing glacial habitats

“…For instance, we collected thousands of insect larvae of selected target species of chironomids, mayflies, stoneflies, and caddisflies to study the effects of pesticides, pharmaceuticals, and personal care products on insects inhabiting glacier‐fed streams (e.g. Lencioni et al ., 2018; Villa et al ., 2018; Di Nica et al ., 2019); constructing the molecular phylogenies of specific chironomid genera, such as Diamesa (Lencioni et al ., 2021b); measuring cold hardiness (Lencioni et al ., 2015) and thermotolerance (e.g. Lencioni & Bernabò, 2017; Bernabò et al ., 2020); examining physiological adaptation to hypoxia (Lencioni et al ., 2008); and analysing the processes of food web using 13 C and 15 N isotopes (Lencioni et al ., 2019).…”