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Two strains of landrace farmhouse yeast cultures from Chuvashia, Russia were analyzed by Richard Preiss of [[Escarpment Laboratories]] referred to by the family names "Rima" and "Marina" (see this [https://twitter.com/larsga/status/889136705571356673 tweet] and [https://twitter.com/larsga/status/887938191721988096 this tweet] by Lars Marius Garshol, and the full [http://www.garshol.priv.no/blog/399.html blog post by Lars]). The lab performed ITS sequencing, PCR fingerprinting, and mini 7 day ferments with these strains. Both of the strains are ''S. cerevisiae'', and they are both POF+ (phenol producers), which is distinct from Norwegian kveik strains which are POF- (do not produce phenols). Russian farmhouse yeast that remains unpurified by a lab is called "zakvaska" <ref>[http://www.garshol.priv.no/blog/399.html Lars Marius Garshol. "Brewing in Chuvashia". Larsblog. 02/04/2019.]</ref>.
According to the PCR fingerprinting, Rima contained at least two strains of ''S. cerevisiae'' but maybe more, as well as a strain of ''Pichia kudriavzevii'' (a fairly common beer contaminant). The first strain of ''S. cerevisiae'' was described as "fruity, relatively clean, and fermented similar to WLP001". The second strain of ''S. cerevisiae'' produced high amounts of diacetyl and under attenuated. The ''Pichia'' was described as "pretty gross and didn't attenuate much(on its own)".
Marina contained what appears to be three closely related ''S. cerevisiae'' strains. They all showed pretty low attenuation after one week, but subsequent fermentations can be carried out longer. The flavors were described as "pretty neutral". There is a fourth yeast strain in the Marina that has yet to be identified <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1800586383302901/?comment_id=2288654764496058&comment_tracking=%7B%22tn%22%3A%22R%22%7D Richard Preiss. Milk The Funk Facebook group thread update about Russian landrace farmhouse yeast. 09/21/2018.]</ref>.