Integration of molecular, ecological, morphological and endosymbiont data for species delimitation within thePnigalio soemiuscomplex (Hymenoptera: Eulophidae)

Abstract

Integrative taxonomy is a recently developed approach that uses multiple lines of evidence such as molecular, morphological, ecological and geographical data to test species limits, and it stands as one of the most promising approaches to species delimitation in taxonomically difficult groups. The Pnigalio soemius complex (Hymenoptera: Eulophidae) represents an interesting taxonomical and ecological study case, as it is characterized by a lack of informative morphological characters, deep mitochondrial divergence, and is susceptible to infection by parthenogenesis-inducing Rickettsia. We tested the effectiveness of an integrative taxonomy approach in delimiting species within the P. soemius complex. We analysed two molecular markers (COI and ITS2) using different methods, performed multivariate analysis on morphometric data and exploited ecological data such as host-plant system associations, geographical separation, and the prevalence, type and effects of endosymbiont infection. The challenge of resolving different levels of resolution in the data was met by setting up a formal procedure of data integration within and between conflicting independent lines of evidence. An iterative corroboration process of multiple sources of data eventually indicated the existence of several cryptic species that can be treated as stable taxonomic hypotheses. Furthermore, the integrative approach confirmed a trend towards host specificity within the presumed polyphagous P. soemius and suggested that Rickettsia could have played a major role in the reproductive isolation and genetic diversification of at least two species.

Three new species in the harvestmen genus Acuclavella (Opiliones, Dyspnoi, Ischyropsalidoidea), including description of male Acuclavella quattuor Shear, 1986

“…In taxonomy, DFAs are almost exclusively used to differentiate between morphologically similar species that are difficult to identify from single characteristics (see Klimov et al 2004, Seifert 2003, Fisher 1936, Lubishew 1962). Multispecies delimitation via DFA, as done here, is becoming more common (see Schlick-Steiner et al 2006, Schönhofer and Martens 2008, Gebiola et al 2012). …”

Cophylogenetic relationships between Anicetusparasitoids (Hymenoptera: Encyrtidae) and their scale insect hosts (Hemiptera: Coccidae)

“…Several recent DNA-based studies strongly suggest that morphologically similar lineages traditionally considered as single species are instead genetically isolated, and in many cases host-specific [40-43]. Koinobiont parasitic Hymenoptera, in particular, display an intricate physiological relationship with their hosts and consequently tend to have relatively narrow host ranges [44].…”

Parasitoid complex (Hymenoptera: Eulophidae) of the leaf-mining fly Chromatomyia horticola (Goureau) (Diptera: Agromyzidae) in Russia

“…Bouček & Askew 1968). In contrast to these results, Gebiola et al (2012) reared this species from Neochrysocharis formosus is also accepted as a valid species, as confirmed by molecular investigation by Tetsuya et al (2011).…”