Adaptive divergence in the neglected alpine mossLewinskya killiasii(Orthotrichaceae), an example of vicariance on different rock types in bryophytes

Abstract

We provide an example of ecological vicariance among two epilithic, high mountain taxa of mosses. Phylogenetic analyses using plastid (rps4-trnS, atpB-rbcL, trnL-trnF) and nuclear (EST-115, EST-317, ITS region) markers and morphological data revealed the distinctiveness of the neglected Orthotrichum killiasii, here resurrected from the synonymy of Lewinskya speciosa and newly combined in Lewinskya. Furthermore, our data indicate a speciation process within O. killiasii related to the rock type inhabited (silicate vs. carbonate). We translate this into the recognition of two subspecies, corresponding to O. killiasii s.s. and the recently described O. simonyi. The incongruence between nuclear and plastid markers in some accessions and the partial but rare incongruence between ITS ribotypes and the morphological manifestation in phenotypes indicate incomplete lineage sorting with respect to rather recent segregation and possible gene flow between the two entities.

Morphological, genetic and ecological divergence in near-cryptic bryophyte species widespread in the Holarctic: the Dicranum acutifolium complex (Dicranales) revisited in the Alps

“…The two species thus represent ecological vicariants. Cryptic or near-cryptic species associated with ecological vicariance have been observed in various groups of plants, animals and fungi (e.g., Boissin et al 2011 ; Douglas et al 2011 ; Douhan et al 2008 ; Reis et al 2020 ) but were rarely reported from bryophytes (Kiebacher et al 2022 ). Only recently, Kiebacher et al ( 2022 ) described a similar example in the epilithic moss Lewinskya killiasii (Müll.…”

“…The protocols to generate the sequence data followed previous work (Kiebacher et al 2021 , 2022 ). In brief, genomic DNA was extracted using the NaOH method (Werner et al 2002 ), we targeted the nuclear ITS region including partial sequence of 18S rRNA gene, ITS1, 5.8S rRNA gene, ITS2 and partial sequence of 26S rRNA gene using the primers m-18-S (Spagnuolo et al 1999 ) and m-25-R (Stech and Frahm 1999 ), and the plastid spacer trnL–trnF including partial sequences of the trnL - and trnF -genes using the primers TabC and TabF (Taberlet et al 1991 ).…”

“…However, they may occur on divergent substrates, but to date, this hypothesis has not been investigated. Different substrate affinities have often been observed between closely related plant species, including bryophytes (Kiebacher et al 2022 ).

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