The Lymnaeidae constitute a significant part of the freshwater molluscan diversity of Greenland. Since 1842, not less than 10 nominal taxa of the species and variety rank were described to organize the diversity of the Greenland lymnaeid snails. All previous attempts to revise these taxa were systematically based on morphological evidence only. Here, we provide a molecular analysis of the phylogenetic affinity and systematic status of three alleged species of the Greenland Lymnaeidae: Lymnaea vahlii (Møller, 1842), L. holboellii (Møller, 1842), and L. pingelii (Møller, 1842). We examined the newly collected material and inspected the type series of the three species. Our results show a very tight relationship between the Greenland snails and the Nearctic species Ladislavella catascopium (Say, 1817) s. lato. From the genetic point of view, the Greenland populations should be classified within L. catascopium, albeit probably with the merit of a subspecies status. The three nominal species of lymnaeids described by Møller (1842) are apparently synonyms of each other. Our findings assume a rather recent colonization of Greenland by snails arriving from the North American mainland, which is compatible with the so-called "tabula rasa" hypothesis, proposed to explain the currently observed taxonomic diversity of continental animals and plants of the North Atlantic islands. No lymnaeid species endemic to Greenland is thus revealed.
A lexicostatistical classification is proposed for 20 languages and dialects of the Lezgian group of the North Caucasian family, based on meticulously compiled 110-item wordlists, published as part of the Global Lexicostatistical Database project. The lexical data have been subsequently analyzed with the aid of the principal phylogenetic methods, both distance-based and character-based: Starling neighbor joining (StarlingNJ), Neighbor joining (NJ), Unweighted pair group method with arithmetic mean (UPGMA), Bayesian Markov chain Monte Carlo (MCMC), Unweighted maximum parsimony (UMP). Cognation indexes within the input matrix were marked by two different algorithms: traditional etymological approach and phonetic similarity, i.e., the automatic method of consonant classes (Levenshtein distances). Due to certain reasons (first of all, high lexicographic quality of the wordlists and a consensus about the Lezgian phylogeny among Caucasologists), the Lezgian database is a perfect testing area for appraisal of phylogenetic methods. For the etymology-based input matrix, all the phylogenetic methods, with the possible exception of UMP, have yielded trees that are sufficiently compatible with each other to generate a consensus phylogenetic tree of the Lezgian lects. The obtained consensus tree agrees with the traditional expert classification as well as some of the previously proposed formal classifications of this linguistic group. Contrary to theoretical expectations, the UMP method has suggested the least plausible tree of all. In the case of the phonetic similarity-based input matrix, the distance-based methods (StarlingNJ, NJ, UPGMA) have produced the trees that are rather close to the consensus etymology-based tree and the traditional expert classification, whereas the character-based methods (Bayesian MCMC, UMP) have yielded less likely topologies.
Geographic variation and differentiation of the chloroplast DNA haplotypes and morpho-anatomical leaf parameters were assessed in a number of eastern European groups of Calluna vulgaris (L.)Hull populations and in the Pritobolien group of populations of this species in Western Siberia, which have long been isolated from the European populations. Sharply pronounced genetic and phenotypic distances and their gradients between the Pritobolien and European population groups were revealed. These distances were many times higher than those between the relatively homogeneous eastern European groups. The data obtained generally supported the hypothesis on the phenogenetic divergence of the Pritobolien marginal populations of C. vulgaris from the European, probably at the subspecies level.
Chamaedrilus (earlier referred to as Cognettia) is a well-known genus of terrestrial and limnic enchytraeids, currently with 19 known species in the world. Some of its species are morphologically cryptic and can only be identified using genetic (DNA) information. Many of them reproduce asexually, and the prevalence of sexual mature individuals is generally low in the populations. Chamaedrilus asloae sp. nov. (Clitellata: Enchytraeidae) is described based on material from two rivers in Norway, one in Sweden, and from a wet deciduous forest in Denmark. With the material at hand, no morphological characters completely separate C. asloae from C. chalupskyi; none of the available specimens of the new species are sexually mature. However, four molecular markers (two mitochondrial, two nuclear) support that C. asloae is a distinct, separately evolved lineage, which is sister to a clade consisting of C. glandulosus and C. varisetosus. In this study, too, the fully developed sexual organs of C. chalupskyi and C. varisetosus are described and illustrated.
The small synanthropic and peregrine earthworm Microscolex phosphoreus (Dugès, 1837) is reported for the first time from Siberia. Morphological and DNA barcode (COI) analyses of this and widely separate samples worldwide demonstrate that, as currently identified, M. phosphoreus is a heterogeneous taxon, with divergent lineages occurring often in the same locality and hardly providing geographically structured genetic signals. The combined morphological and genetic evidence suggests that at least four of the found clades should be reclassified as separate species, both morphologically and genetically distinct from each other. However, as the specimen number was limited and only the COI gene was studied for the genetic work, we hesitate in formally describing new species. There would also be the problem of assigning the available names to specific lineages. Our findings encourage careful external and anatomical examination and using reliable characters such as the interchaetal distances and spermathecal morphology for correct identification and for deeper evaluation of cryptic diversity in this interesting bioluminescent worm.
An analysis of the phylogenetic position of the Olkhon mountain vole (Alticolaolchonensis Litvinov 1960) using the sequences of four nuclear (BRCA, GHR, LCAT, and IRBP) and one mitochondrial (cyt. b) genes was undertaken. It was noted that, until recently, multiple studies of the systematic position of this vole had been based exclusively on morphological data, while the major taxonomic traits contained contradictory information regarding both the subgeneric status of this species and its genus. It was established that the molecular data and morphology data allow us to attribute the Lake Baikal vole unambiguously to the nominative subgenus Alticola instead of Aschizomys.
A tentative novel member of the genus Lyssavirus, designated as Kotalahti bat lyssavirus, was detected in a Brandt's bat (Myotis brandtii) in Finland. Based on phylogenetic analysis, the virus differs from other known lyssaviruses, being closely related to Khujand virus, Aravan virus, Bokeloh bat lyssavirus and European bat lyssavirus 2.
Charrs of the genus Salvelinus (including Salvethymus) represent a monophyletic group of salmonid fishes that diverged from the common ancestor without subdivision into subgenera. The phylogenesis of the genus is characterized by four cycles of mitochondrial genome divergence. The first one, belonging to the Late Miocene--the border between Miocene and Pliocene (6 to 4 million years ago)--was associated with the consecutive divergence of the S. fontinalis, S. namaycush, S. levanidovi, and S. leucomaenis basal branches. Two divergence events, including separation of the ancestral lineage of western Pacific group of S. m. krascheninnikovi and the following segregation of the common ancestor into two mitochondrial phyla, happened within the period of 3 to 2 million years ago. The next cycle is attributed to the time interval of about 1 million years ago and includes the divergence of both phyla. In one phylum, a relatively quick isolation of Arctic and eastern Pacific phylogroups, along with the divergence of the latter phylogroup into S. confluentus and S. m. lordi lineages, took place. At the same time, the second phylum diverged into the S. m. malma and S. alpinus phylogenetic groups. At the final stage (Middle to Late Pleistocene), differentiation of the taxa within the phylogenetic groups took place.
We use analysis of mitochondrial DNA barcodes in combination with published data on morphology to rearrange the taxonomy of two arctic species, Gynaephora groenlandica and G. rossii. We demonstrate that (1) the taxon lugens Kozhanchikov, 1948 originally described as a distinct species is a subspecies of Gynaephora rossii, and (2) the taxon kusnezovi Lukhtanov et Khruliova, 1989 originally described as a distinct species in the genus Dicallomera is a subspecies of Gynaephora groenlandica. We also provide the first evidence for the occurrence of G. groenlandica in the Palearctic region (Wrangel Island).
The taxonomy of Zelentia Korshunova, Martynov Picton, 2017, a genus of aeolidacean nudibranchs recently separated from Trinchesia Ihering, 1879, is reviewed. Using previous and novel data, including the defining morphological characters of a supplementary gland inserted into the penis, which is also armed with stylet, it is demonstrated that the genus Zelentia is a well-established amphi-boreal taxon. A phylogenetic tree and haplotype network for species of the genus Zelentia are provided. A new species from the Northeastern Pacific, Zelentia willowsi sp. nov. and a second Northeastern Pacific species, Zelentia nepunicea sp. nov., previously thought to be "Cuthona" pustulata (Alder Hancock, 1854), are described using morphological and molecular data. A new species from the North Atlantic and sub-Arctic White Sea, Zelentia roginskae sp. nov., is also described using morphological and molecular data. The Northeastern Pacific Zelentia nepunicea sp. nov. and"Cuthona" punicea Millen, 1986, which externally share a similar reddish colouration, are shown to belong to two different families since "Cuthona" punicea possesses a supplementary gland inserted into the vas deferens and an unarmed penis, characters of the genus Cuthonella Bergh, 1884, belonging to the Cuthonellidae family. Despite belonging to different families and having significant internal differences, externally Cuthonella punicea and Zelentia nepunicea sp. nov. appear similar, thus the new sympatric species of Zelentia is given the name Z. nepunicea sp. nov. which means non punicea. To facilitate identification and avoid further confusion we provide a comparative table which encompasses diagnostic morphological data for Northeastern Pacific species of the families Cuthonidae, Cuthonellidae and Trinchesiidae which are externally similar to the described new taxa.