Meeting in Liguria : hybridisation between Apennine endemic Euphorbia barrelieri and western Mediterranean E. nicaeensis led to the allopolyploid origin of E. ligustica

Skubic, Maruša (author), Záveská, Eliška (author), Frajman, Božo (author)

The Mediterranean Basin is renowned for its extremely rich biota and is considered as one of the 25 Global Biodiversity Hotspots, but its diversity is not homogeneously distributed. Outstanding in the number of (endemic) species are the Ligurian Alps (Italy). At the foot of the Ligurian Alps, little above the Mediterranean Sea, a disjunct occurrence of Italian endemic Euphorbia barrelieri was reported. Using an array of integrative methods ranging from cytogenetic (chromosome number and relative genome size estimation), over phylogenetic approaches (plastid, ITS and RAD sequencing) to multivariate morphometrics we disentangled the origin of these populations that were shown to be tetraploid. We performed phylogenetic analyses of the nuclear ITS and plastid regions of a broad taxonomic sampling of Euphorbia sect. Pithyusa to identify possible species involved in the origin of the tetraploid populations and then applied various analyses of RADseq data to identify the putative parental species. Our results have shown that the Ligurian populations of E. barrelieri are of allotetraploid origin that involved E. barrelieri and western Mediterranean E. nicaeensis as parental species. We thus describe a new species, E. ligustica, and hypothesise that its adaptation to similar environments in which E. barrelieri occurs, triggered development of similar morphology, whereas its genetic composition appears to be closer to that of E. nicaeensis. Our study emphasises the importance of polyploidisation for plant diversification, highlights the value of the Ligurian Alps as a hotspot of biodiversity and endemism and underlines the importance of integrative taxonomic approaches in uncovering cryptic diversity.

• Language: English
• Keywords: integrative taxonomy, Ligurian Alps, morphometrics, new species, phylogenetics, polyploidy, RAD sequencing
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: BF - Biotechnical Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2023
• Number of pages: 15 str.
• Numbering: art. no. ǂ107805, Vol. 185
• PID: 20.500.12556/RUL-146423
• UDC: 58
• ISSN on article: 1055-7903
• DOI: 10.1016/j.ympev.2023.107805
• COBISS.SI-ID: 154027267
• Publication date in RUL: 31.05.2023

Record is a part of a journal

• Title: Molecular phylogenetics and evolution
• Shortened title: Mol. phylogenet. evol.
• Publisher: Academic Press
• ISSN: 1055-7903
• COBISS.SI-ID: 617551

Licences

• License: CC BY-NC-ND 4.0, Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
• Link: http://creativecommons.org/licenses/by-nc-nd/4.0/
• Description: The most restrictive Creative Commons license. This only allows people to download and share the work for no commercial gain and for no other purposes.

Secondary language

• Language: Slovenian
• Keywords: taksonomija, Ligurske alpe, morfometrija, nove vrste, filogenetika, poliploidija, sekvenciranje