and they are occasionally seen in public aquaria. The most economically important of these fishes, for which fisheries and aquaculture operations exist, are the grayling (T. thymallus) and the Arctic grayling (T. arcticus). Name The name of the genus Thymallus first given to grayling (T. thymallus) described in the 1758 edition of Systema Naturae by Swedish zoologist Carl Linnaeus originates from the faint smell of the herb thyme, which emanates from the flesh. Thymallus derives from the Greek θύμαλλος, "thyme smell". Species According to FishBase, 14 species are placed in this genus. However, views differ on their taxonomic rank. Thymallus arcticus (Pallas, 1776) - Arctic grayling Thymallus baicalensis Dybowski, 1874 - Baikal black grayling Thymallus brevipinnis Svetovidov (ru), 1931 - Baikal white grayling Thymallus brevirostris Kessler, 1879 - Mongolian grayling Thymallus burejensis Antonov, 2004 Thymallus flavomaculatus Knizhin, Antonov & Weiss, 2006 - yellow-spotted grayling Thymallus grubii Dybowski, 1869 - Amur grayling Thymallus mertensii Valenciennes, 1848 Thymallus nigrescens Dorogostaisky, 1923 - Kosogol grayling Thymallus pallasii Valenciennes, 1848 - East Siberian grayling Thymallus svetovidovi Knizhin & Weiss, 2009 - Upper Yenisei grayling Thymallus thymallus (Linnaeus, 1758) - grayling Thymallus tugarinae Knizhin, Antonov, Safronov & Weiss, 2007 - Lower Amur grayling Thymallus yaluensis T. Mori, 1928 Modern reviews and the Catalog of Fishes also list additional species including Thymallus nikolskyi , Thymallus baicalolenensis and Thymallus ligericus . An old controversy exists over the status of Baikal black vs white graylings, T. baicalensis and T. brevipinnis. Modern research supports the view that they are not separate taxa, but alternative ecological forms of T. baicalensis. References Extant Pleistocene first appearances Ray-finned fish genera Holarctic fauna