A hairy case: The evolution of filtering carnivorous Drusinae (Limnephilidae, Trichoptera)

Abstract

The caddisfly subfamily Drusinae BANKS comprises roughly 100 species inhabiting mountain ranges in Europe, Asia Minor and the Caucasus. A 3-gene phylogeny of the subfamily previously identified three major clades that were corroborated by larval morphology and feeding ecologies: scraping grazers, omnivorous shredders and filtering carnivores. Larvae of filtering carnivores exhibit unique head capsule complexities, unknown from other caddisfly larvae. Here we assess the species-level relationships within filtering carnivores, hypothesizing that head capsule complexity is derived from simple shapes observed in the other feeding groups. We summarize the current systematics and taxonomy of the group, clarify the systematic position of Cryptothrix nebulicola, and present a larval key to filtering carnivorous Drusinae. We infer relationships of all known filtering carnivorous Drusinae and 34 additional Drusinae species using Bayesian species tree analysis and concatenated Bayesian phylogenetic analysis of 3805bp of sequence data from six gene regions (mtCOI5-P, mtCOI3-P, 16S mrDNA, CADH, WG, 28S nrDNA), morphological cladistics from 308 characters, and a total evidence analysis. All analyses support monophyly of the three feeding ecology groups but fail to fully resolve internal relationships. Within filtering carnivores, variation in head setation and frontoclypeus structure may be associated with progressive niche adaptation, with less complex species recovered at a basal position. We propose that diversification of complex setation and frontoclypeus shape represents a recent evolutionary development, hypothetically enforcing speciation and niche specificity within filtering carnivorous Drusinae.

First systematic investigation of adults and second checklist of caddisflies of the Plitvice Lakes National Park with notes on research history, biodiversity, distribution and ecology

“…These diverse habitats enable the formation of specific microhabitats, provide all food types for caddisflies (Graf et al, 2008) and ensure the exploitation of energy resources which is important for their speciation, evolution and biodiversity (Pauls et al, 2008;Vitecek et al, 2015).…”

“…For example, family Odontoceridae with one species in the Plitvice Lakes NP, O. albicorne Scopoli has ecological adaptations to streams and rivers (Tabs 1-3, 5). While D. croaticus Marinković-Gospodnetić and all species from subfamily Drusinae (family Limnephilidae) have adaptations to springs and the crenal parts of mountain streams (Kučinić et al, 2008(Kučinić et al, , 2016Previšić et al, 2014;Vitecek et al, 2015Vitecek et al, , 2017Waringer et al, 2015). Additionally, species from the family Glossostomatidae were restricted to the same aquatic habitats (crenal part of streams) while, for instance, Tinodes unicolor Pictet is a specialist at tufa barriers (Edington & Hildrew, 1995).…”

Description of two new filtering carnivore Drusus species (Limnephilidae, Drusinae) from the Western Balkans

“…Ecologically, most species are crenobiont (Graf et al 2008), and as larvae fall into one of three different feeding groups: filtering carnivores, omnivorous shredders and scraping grazers (Pauls et al 2008, Graf et al 2009). The adults of each larval feeding group are also characterized by a set of synapomorphies (Vitecek et al in press). Filtering carnivorous Drusinae males uniquely exhibit laterally positioned gland openings at the fifth abdominal sternite and parallel wing veins in the hind wing anal field (depicted in Vitecek et al in press).…”

Trichoptera endemic in the Carpathian Basin and the adjacent areas

“…Drusus meridionalis Kumanski, 1973: Vitecek et al (2015a: raised to species level by performance of morphological data in phylogenetic reconstruction of Drusinae.…”