Steven Weiss: Species diversity, biogeography and conservation status of graylings (_Thymallus_)
Channel: Fishbase Sweden
Date: 08/11/2022

Steven Weiss, University of Graz, Austria, gave a lecture on "Species diversity, biogeography and conservation status of graylings (Thymallus) throughout their range" at Fishbase Symposium 2022 in Stockholm, Sweden, October 17, 2022.

ABSTRACT: I will discuss and outline the present state of knowledge concerning the number of recognized species of grayling (_Thymallus_) throughout their European, Asian, and North American range.

Graylings are perhaps one of the less studied genera of salmonid fishes, a family of fishes well-known for their value in commercial and sport fisheries, as well as high ecological role in cold, temperate freshwater systems. In recent years, a better understanding of their diversity, especially in Asia has developed, largely through the complimentary use of state-of-art genetic data acquisition and traditional phenotypic observations and morphological measurements. To date, our data support the recognition of 13 grayling species, whereby there is potential for several unrecognized species, and some taxonomic uncertainties or controversies. 

In this talk published mitogenome based phylogeny will be combined with unpublished ddRAD sequence data to provide a robust phylogenetic overview of the genus. A few instances of cyto-nuclear discordance and its causes will be presented. For Europe, a more detailed view of our current knowledge on the biogeographic history will be discussed, along with a quick view into ongoing similar analysis for the Asian and North American range of the genus. 
The conservation status of each species will be presented along with a range of open questions on the evolutionary history and systematic diversity of the genus as a whole, as well as a few enigmatic species or regions of grayling range that have not yet been adequately explored.