Description of a new species of Wormaldia from Sardinia and a new Drusus species from the Western Balkans (Trichoptera, Philopotamidae, Limnephilidae)

Larval morphology of the Western Balkans endemic caddisflies Drusus krusniki Malicky 1981, D. vernonensis Malicky 1989, and D. vespertinus Marinković 1976 (Trichoptera, Limnephilidae, Drusinae)

Drusinae (Trichoptera, Limnephilidae) are highland caddisflies inhabiting high-gradient, turbulent running water and spring habitats. They are disjunctly distributed over the Eurasian mountain ranges, and the majority of species is endemic to particular mountain areas. The most diverse of three main groups of the Drusinae, the grazer clade, consists of species in which larvae feed on epiltihic biofilm and algae. In this paper we describe three previously unknown grazer-clade Drusinae larvae: Drusus krusniki Malicky 1981 (endemic to the Dinaric western Balkans), D. vernonensis Malicky 1989 (endemic to the Hellenic western Balkans), and D. vespertinus Marinković 1976 (endemic to the Dinaric western Balkans). The larvae of these species have toothless mandibles typical of the Drusinae grazer clade. Larvae and adults were unambiguously associated using molecular genetic data, i.e., the mitochondrial cytochrome oxidase I gene fragment (mtCOI3-P). Morphological characteristics of the larvae are described and the diagnostic features enabling species-level identification are illustrated. We further discuss the ecology and distribution of three Western Balkan endemic species.

Integrative taxonomy by molecular species delimitation: multi-locus data corroborate a new species of Balkan Drusinae micro-endemics

BACKGROUND

Taxonomy offers precise species identification and delimitation and thus provides basic information for biological research, e.g. through assessment of species richness. The importance of molecular taxonomy, i.e., the identification and delimitation of taxa based on molecular markers, has increased in the past decade. Recently developed exploratory tools now allow estimating species-level diversity in multi-locus molecular datasets.

RESULTS

Here we use molecular species delimitation tools that either quantify differences in intra- and interspecific variability of loci, or divergence times within and between species, or perform coalescent species tree inference to estimate species-level entities in molecular genetic datasets. We benchmark results from these methods against 14 morphologically readily differentiable species of a well-defined subgroup of the diverse Drusinae subfamily (Trichoptera, Limnephilidae). Using a 3798 bp (6 loci) molecular data set we aim to corroborate a geographically isolated new species by integrating comparative morphological studies and molecular taxonomy.

CONCLUSIONS

Our results indicate that only multi-locus species delimitation provides taxonomically relevant information. The data further corroborate the new species Drusus zivici sp. nov. We provide differential diagnostic characters and describe the male, female and larva of this new species and discuss diversity patterns of Drusinae in the Balkans. We further discuss potential and significance of molecular species delimitation. Finally we argue that enhancing collaborative integrative taxonomy will accelerate assessment of global diversity and completion of reference libraries for applied fields, e.g., conservation and biomonitoring.

Morphological features of larvae of Drusus plicatus Radovanović (Insecta, Trichoptera) from the Republic of Macedonia with molecular, ecological, ethological, and distributional notes

A description of the larva of Drusus plicatus Radovanović is given for the first time. The most important diagnostic characters enabling separation from larvae of the other Drusinae from the southeast Europe are listed. Molecular, ecological, and ethological features and distribution patterns of the species are given. Additionally, information on the sympatric caddisfly species of the three springs where larvae and adults of Drusus plicatus were found and presented.

Drusus sharrensis sp. n. (Trichoptera, Limnephilidae), a new species from Sharr National Park in Kosovo, with molecular and ecological notes

In this paper we describe Drusussharrensissp. n., from the Sharr Mountains in Kosovo. Males of the new species are morphologically most similar to Drususkrusniki Malicky, 1981, Drususkerek Oláh, 2011 and Drususjuliae Oláh, 2011 but differ mainly in exhibiting (1) a differently shaped spinose area on tergite VIII; (2) intermediate appendages anteriorly curved in lateral view with broad tips in dorsal view; (3) inferior appendages with a distinct dorsal protrusion in the proximal half. Females of the new species are morphologically most similar to Drususkrusniki, Drususkerek, Drususjuliae, and Drususplicatus Radovanovic, 1942 but mainly differ in (1) segment X that is longer than the supragenital plate with distinctly pointed tips; (2) supragenital plate quadrangular with a distinct round dorsal protrusion; (3) a vulvar scale with a small median lobe. Results of phylogenetic species delimitation support monophyly of Drusussharrensis sp. n. and recover it as sister to a clade comprising (Drususpelasgus Oláh, 2010 + Drususjuliae + Drususarbanios Oláh, 2010 + Drususplicatus + (Drususdacothracus Oláh, 2010 + Drususillyricus Oláh, 2010)). The new species is a micro-endemic of the Sharr Mountains, a main biodiversity hotspot in the Balkan Peninsula. Main threats to the aquatic ecosystems of this part of the Balkan Peninsula are discussed.

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

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.

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

Two new species of the genus Drusus (Trichoptera, Limnephilidae, Drusinae) from the Western Balkans are described. Additionally, observations on the biodiversity and threats to the region's endemic aquatic fauna are discussed. Drususkrpachi sp. n. is a micro-endemic of the Korab Mountains, Macedonia, and Drususmalickyi sp. n. is a micro-endemic of the Prokletije Mountains, Albania. Both new species are most similar to Drususmacedonicus but differ from the latter in the shape of segment IX, the shape of the tips of the intermediate appendages in lateral view, the shape of the inferior appendages, and the form and shape of the parameres. In addition, males of the European species of filtering carnivore Drusinae are diagnosed and illustrated, including Cryptothrixnebulicola McLachlan, Drususchrysotus Rambur, Drususdiscolor Rambur, Drususmacedonicus Schmid, Drususmeridionalis Kumanski, Drususmuelleri McLachlan, Drususromanicus Murgoci and Botosaneanu, and Drusussiveci Malicky. These additions to the Western Balkan fauna demonstrate the significance of this region for European biodiversity and further highlight the importance of faunistic studies in Europe.