Intraspecific taxonomy of Muscari botryoides s. l. (Asparagaceae s. l. / Hyacinthaceae s. str.): history of research and synonymy

Muscari botryoides (L.) Mill. s. l. (Asparagaceae s. l. / Hyacinthaceae s. str.) is a taxonomically complicated species (or a species aggregate) with a high level of intraspecific polymorphism. Since it has been taxonomically established, a large number of taxa of different ranks have been identified for various regions of Europe, such as Muscari lelievrei Boreau, M. motelayi Foucaud – for France, M. transsilvanicum Schur – for Romania, Botryanthus kerneri Marches., Muscari longifolium Rigo – for Italy, M. botryoides subsp. hungaricum Priszter – for Hungary, M. botryoides var. podolicum Zapał., M. carpaticum Racib. and M. pocuticum Zapał. – for Ukraine. The article provides a brief overview of the main publications on intraspecific taxonomy of M. botryoides. A list of selected synonyms (mainly taxa mentioned for the flora of Ukraine) of the species is provided. It is noted that the intraspecific taxonomy of M. botryoides remains unresolved in many aspects.

Phenotypic differentiation of the slow worm lizards (Squamata: Anguis) across their contact zone in Central Europe

Background The application of molecular-phylogenetic approaches to taxonomy has had a dramatic effect on our understanding of the diversity of reptiles. These approaches have allowed researchers to reveal previously hidden lineages as well as taxonomic overestimation in morphologically plastic taxa. Slow worms, legless lizards of the genus Anguis (Squamata: Anguidae), were previously considered to comprise either one or two species, and morphology-based intraspecific taxonomy of Anguis fragilis remained controversial throughout the 20th century. After the discovery of deep genetic divergences within the genus, its taxonomy was reconsidered, and as a result, five extant species have been recognized. In order to better understand the patterns of their interspecific differentiation, here we studied phenotypic differences between the two most widespread of them—A. fragilis and A. colchica, and their putative hybrids across the contact zone of both species in Central Europe. Methods We used multivariate and univariate statistics and analyzed ten metric, eleven meristic, and six categorical phenotypic variables in material comprising a total of 326 individuals. We also genotyped individuals from the contact zone for one mitochondrial and two nuclear DNA fragments in order to delineate the distribution of individuals of hybrid and non-hybrid origin. The clines in morphological traits were studied using HZAR. Results We show that the two species are morphologically differentiated. Anguis fragilis has a less robust head, fewer scales covering the body, lower frequency of the external ear opening presence, lower frequency of separated prefrontal scales, higher frequency of prefrontal scales in contact with each other, and body coloration more similar to the juvenile coloration than A. colchica. Slow worms from the contact/hybrid zone are characterized by an intermediate morphology, with more similarities to A. fragilis than to A. colchica. Discussion None of the analyzed characters alone proved to be fully diagnostic, although more than 90% of all individuals could be successfully assigned to one or another species based on numbers of scales around the body. Our results indicate concordant, coincident, and steep clines in character states change. We present several hypotheses on the origin and evolutionary maintenance of the morphological divergence between both species and suggest that different evolutionary histories of the taxa rather than recently acting selection explain the observed morphological variation.

Mitochondrial DNA diversity of the alpine newt (Ichthyosaura alpestris) in the Carpathian Basin: evidence for multiple cryptic lineages associated with Pleistocene refugia

The phylogeography and molecular taxonomy of the Alpine newt, Ichthyosaura alpestris, has been intensively studied in the past. However, previous studies did not include a comprehensive sampling from the Carpathian Basin, possibly a key region in the evolution of the species. We used a 1251 bp long fragment of the mitochondrial genome to infer the species’ evolutionary history in central-eastern Europe by assigning isolated Carpathian Basin populations from 6 regions to previously defined mtDNA lineages. We also revised the morphology-based intraspecific taxonomy of the species in the light of new genetic data. Alpine newt populations from the Carpathian Basin represented two different mitochondrial lineages. The Mátra, Bükk and Zemplén Mts populations can be assigned to the Western lineage of the nominotypical subspecies. Bakony and Őrség populations showed high haplotype diversity and formed a separate clade within the Western lineage, suggesting that the Carpathian Basin might have provided cryptic refugia for Alpine newt populations in their cold-continental forest-steppe landscapes during the younger Pleistocene. Newts from Apuseni Mts were related to the Eastern lineage but formed a distinct clade within this lineage. Considering the morphological and genetic differentiation of the Bakony and Őrség populations, consistent with a long independent evolutionary history, we propose these populations be referred to as Ichthyosaura alpestris bakonyiensis (Dely, 1964). We provide a redescription of this poorly known subspecies.

Mitochondrial DNA Analysis Clarifies Taxonomic Status of the Northernmost Snow Sheep (Ovis nivicola) Population

Currently, the intraspecific taxonomy of snow sheep (Ovis nivicola) is controversial and needs to be specified using DNA molecular genetic markers. In our previous work using whole-genome single nucleotide polymorphism (SNP) analysis, we found that the population inhabiting Kharaulakh Ridge was genetically different from the other populations of Yakut subspecies to which it was usually referred. Here, our study was aimed at the clarification of taxonomic status of Kharaulakh snow sheep using mitochondrial cytochrome b gene. A total of 87 specimens from five different geographic locations of Yakut snow sheep as well as 20 specimens of other recognized subspecies were included in this study. We identified 19 haplotypes, two of which belonged to the population from Kharaulakh Ridge. Median-joining network and Bayesian tree analyses revealed that Kharaulakh population clustered separately from all the other Yakut snow sheep. The divergence time between Kharaulakh population and Yakut snow sheep was estimated as 0.48 ± 0.19 MYA. Thus, the study of the mtDNA cytb sequences confirmed the results of genome-wide SNP analysis. Taking into account the high degree of divergence of Kharaulakh snow sheep from other groups, identified by both nuclear and mitochondrial DNA markers, we propose to classify the Kharaulakh population as a separate subspecies.

The role of Prunus cerasifera Ehrh. in the origin, evolution and improvement of stone fruit cultivars

At Krymsk Experiment Breeding Station of VIR, as a result of collecting, studying, and selective use of myrobalan plum genetic diversity, the intraspecific taxonomy of the species Prunus cerasifera Ehrh. was clarified. Donors of traits significant for breeding were identified and, with their use, adaptable cultivars of myrobalan plum, Russian plum and clonal rootstocks of stone fruit plants were developed.Intraspecific classification of P. cerasifera is proposed, with the identified subspecies:subsp. cerasifera (typical myrobalan plum);subsp. orientalis (M. Pop.) Erem. et Garcov. (Oriental myrobalan plum);and subsp. macrocarpa Erem. et Garcov. (large-fruited myrobalan plum).Within subsp. P. cerasifera subsp. macrocarpa, varieties were identified:var. macrocarpa (typical, or Krymsk);var. georgica Erem. et Garcov. (Georgian);var. iranica (Koval.) Erem. et Garcov. (Iranian);var. nairica (Koval.) Erem. et Garcov. (Armenian);var. pissardii Carr. (Pissard);and var. taurica (Kost.) Erem. et Garcov. (Taurida).The participation of myrobalan plum in the origin of spp. P. brigantiaca Vill., P. cocomilia Tem., and P. spinosa L. was traced. Involvement of large-fruited myrobalan plum in hybridization with blackthorn contributed to the manifestation of an exceptional polymorphism among the varieties of the hybridogenic species P. domestica L. (P. cerasifera × P. spinosa). As a result of hybridization between myrobalan plum and Chinese plum varieties, a new cultigen species emerged – Russian plum (× P. rossica Erem.). By now, 127 cultivars of this species and 7 clonal rootstocks for stone fruit crops have been developed. These cultivars and clonal rootstocks are zoned for Russia and a number of other countries.

Morphological and genetic relationships of Myosotis laxa ssp. baltica and ssp. caespitosa, and typification of M. laxa ssp. baltica

Intraspecific taxonomy of <em>Myosotis laxa</em> has been unclear for a long time. <em>M. laxa</em> ssp. <em>baltica</em> has been treated as a microendemic taxon of the Baltic Sea region, which has evolved in the Aland Islands and has spread northwards; the spread to southeast has been declared doubtful. Morphologically intermediate individuals between <em>M. l</em>. ssp. <em>caespitosa</em> and <em>M. l</em>. ssp. <em>baltica</em> exist; these have sometimes been classified as <em>M. l</em>. ssp. <em>laxa</em>. The aim of this paper is to clarify phylogenetic relationships between subspecies of <em>M. laxa</em> s.l. Here, <em>M. laxa</em> ssp. <em>baltica</em> is lectotypified. We proved that typical <em>M. l</em>. ssp. <em>baltica</em> does occur in the south-eastern Baltic region, namely in Estonia, using herbarium and freshly collected material. A group of plants were identified as typical <em>M. l</em>. ssp. <em>baltica</em>, but many specimens showed intermediate characters between <em>M. laxa</em> ssp. <em>baltica</em> and ssp. <em>caespitosa</em>. The two subspecies could be clearly differentiated neither by morphological characteristics nor by ITS sequences.<em> M. laxa</em> s. l. appeared to be monophyletic according to the ITS phylogeny. We propose that <em>Myosotis laxa</em> ssp. <em>baltica</em> is a coastal ecotype of <em>Myosotis laxa</em>, which has adapted to the fluctuating conditions of coastal habitats. Genetically, it has not yet evolved into a separate species and therefore it would be reasonable to assign it a rank of variety. However, further investigation including wider taxon and geographical sampling is needed to finally clarify the position of all subspecies.