Integrative floristics: a modern approach to biodiversity surveys in the molecular era, as applied to an expedition to the Khamar-Daban range, southern Siberia, Russia

ABSTRACT Introduction We report the results of an international bryological expedition to the Khamar-Daban mountain range in Russian southern Siberia. The novel approach of integrative floristics is introduced here as a method of surveying the flora of a region by using a combination of morphological and molecular evidence to identify and verify unexpected findings. We show that use of this approach can deliver a high level of credibility in cases in which direct molecular comparison is possible or the relevant data can be easily obtained from reliable studies informing recent treatments. Integrative floristics can also be used to identify potential taxonomic problems requiring further study. Methods Conventional identification methods based on plant anatomy and morphology were supplemented with molecular barcoding (nuclear ITS, plastid trnL–trnF, rps4 and atpB–rbcL regions) of specimens that either did not fit existing morphological concepts perfectly or for which records were unexpected based on previously established phytogeographical patterns. Key results and conclusions In total, we recorded ca 380 species of mosses and ca 150 species of liverworts from five localities on the northern slopes of the Khamar-Daban range. Such floristic richness indicates a hotspot of bryophyte diversity with a remarkably high proportion of suboceanic species, such as Brachydontium trichodes (F.Weber) Milde, Herzogiella striatella (Brid.) Z.Iwats. and Racomitrium macounii subsp. alpinum (E.Lawton) Frisvoll. Nearly 20% of specimens were identified or checked using DNA barcoding. This approach showed the presence of previously unrecorded species in a number of genera, including Didymodon, Neckera and Pseudohygrohypnum.