First record of Balkan Thymus jankae (Lamiaceae) from Ukraine, with taxonomic remarks on the species

ABSTRACT

The Balkan species Thymus jankae is documented for the first time from Ukraine on Mount Chorna Hora (Vynohradiv town, Transcarpathian region), which is ca. 300 km northwards from its main range. This species locality has long been overlooked due to misidentification of its early collections with other Thymus taxa. Despite its ambiguous taxonomy, available morphological, caryological, biogeographical, and molecular data support a species rank of Th. jankae and suggest its ancestral position within the Thymus praecox-group. Morphology and chromosome count (2n = 56) of plants from Ukraine are congruent with the data available for Balkan populations. Phytosociological survey of Th. jankae locus in Ukraine shows the species to be affiliated with the associations Alysso alyssoidis-Sedetum and Festucetum pseudodalmaticae, as well as a community physiognomically close to the association Potentillo heptaphyllae-Festucetum rupicolae. The first two associations are parts of biotopes (6110 and 6240) with priority status according to Annex I of the Habitats Directive (92/43/EEC) and represent respectively a pioneer community and subpannonic meadow steppe grassland with evident southern European relationships. Most likely, the discovered locality of Th. jankae is a relict northern outpost created by extinction of a part of the former species range, although its anthropogenic origin should not be also excluded. Conservation of Th. jankae in Ukraine on the national level is discussed.

KEYWORDS:

• Thymus
• taxonomy
• distribution
• Ukraine
• Balkans
• species conservation
• chromosome number
• geographical range

Acknowledgments

We are thankful to curators and staff of consulted herbaria and to Ihor P. Antakhovych (Lviv City Children’s Ecological and Naturalistic Center, Ukraine), Józef Mitka (Jagiellonian University in Kraków, Poland) and Pavol Mered’a (Plant Science and Biodiversity Centre, Slovak Academy of Sciences) for their support of this research. Special thanks to Iryna O. Bednarska (Institute of Ecology of the Carpathians, National Academy of Sciences of Ukraine) for identification of Festuca specimens and to Fabrizio Bartolucci (Scuola di Bioscienze e Medicina Veterinaria, Università di Camerino – Centro Ricerche Floristiche dell’Appennino, Parco Nazionale del Gran Sasso e Monti della Laga, Italy) for sharing important hard-to-reach literature. Valuable comments of the editor and anonymous reviewers are gratefully acknowledged.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary material

Supplemental data for this article can be accessed here.

Additional information

Funding

This work was supported by the Queen Jadwiga Fund of Jagiellonian University in Kraków, Poland (granted a scholarship to V.O. Nachychko in 2016) and Slovak Academic Information Agency, SAIA, n. o. (granted a scholarship to V.O. Nachychko under National Scholarship Programme of the Slovak Republic for the Support of Mobility of Students, PhD Students, University Teachers, Researchers and Artists financed by the Government of the Slovak Republic in 2017).

Notes on contributors

Viktor O. Nachychko

Viktor O. Nachychko, Ph.D., is a Research Fellow at the Botanical Garden of Ivan Franko National University of Lviv, Ukraine. His research focuses on the taxonomy, nomenclature, and distribution of the genus Thymus L. (Lamiaceae) in Ukraine and adjacent countries. Contribution: general concept and research question, plant material collection and identification, herbarium work, morphological and microscopic study, interpretation of results, manuscript preparation.

Yevhen V. Sosnovsky

Yevhen V. Sosnovsky, Ph.D., is a Research Fellow at the Botanical Garden of Ivan Franko National University of Lviv, Ukraine. He specializes in systematic and functional leaf anatomy, plant adaptation and evolution, and plant-associate interactions. Contribution: research question, plant material collection, morphological study, interpretation of results, manuscript preparation.

Vitaliy I. Honcharenko

Vitaliy I. Honcharenko, Ph.D., is the Head of the Department of Botany, Faculty of Biology, Ivan Franko National University of Lviv, Ukraine. His area of expertise includes the taxonomy and distribution of the genera Rubus L. and Rosa L. (Rosaceae) in Ukraine and adjacent countries. Contribution: research question, manuscript preparation.