The taxonomic status of Thamnobryum maderense (Kindb.) Hedenas (Bryopsida) as inferred from molecular data
Stech, Michael; Ros, Rosa Maria; Werner, Olaf
CpDNA trnLUAA intron and nrDNA ITS2 sequences of six specimens of Thamnobryum alopecurum (three from the Iberian Peninsula, each one from Morocco, Tenerife and Germany) and four specimens of T. maderense (two from the Iberian Peninsula and two from Morocco) are completely identical, except for one substitution in the trnL intron of T. alopecurum from Germany and one substitution in the ITS2 of T. alopecurum from Morocco and Tenerife. In contrast, Thamnobryum pandum from New Zealand differs in 7 substitutions in the trnL intron and in 3 substitutions and one indel in the ITS2. In the single most parsimonious tree inferred from a combined data set of both molecular markers, the genus Thamnobryum is monophyletic and separated from species of two other genera of the Thamnobryaceae (Porothamnium stipitatum, Porotrichum usagarum). The T. alopecurum/T. maderense specimens form a polytomous branch separated from T. pandum. It is concluded from the molecular similarity that Thamnobryum maderense should not be regarded as a distinct species, but should rather be included in T. alopecurum. A new taxonomic combination is proposed: Thamnobryum alopecurum var. maderense comb. nov.