COSMARIUM TAXICHONDRIFORME EICHLER & GUTWINSKI 1895 – THE FOURTH RECORD OF A RARE DESMID (ZYGNEMATOPHYCEAE, STREPTOPHYTA) IN CHERNIHIV POLESIE

Purpose. Adding new distribution and microphotographs of a rare taxon of the genus Cosmarium found in a small pond in Chernihiv Polesie. Review of the history of this taxon study in Ukraine and its taxonomy, infraspecific taxa characters are compared discussed. Methodology. The new locality of C. taxichondriforme is situated at the border of the landscape reserve of national significance "Zamglai" that is one of the largest eutrophic swamps in the Chernihiv Polesie. During the field research of the Zamglai bog complex, algal samples were collected from a small pond (2000 м2) situated along the road to Hrybova Rudnia village from route E95, at the distance of 1,8 km village and 0.8 km from the route. The samples were fixed with 4 % formalin for further study in laboratory conditions; pH and electrical conductivity of water were measured with a portable pH and conductivity meter. Microscopic examination of the samples was carried out using a light microscope equipped with a camera for taking microphotos. Identification manuals and monographs of the leading Ukrainian (Palamar-Mordvintseva, 1986, 2005) and European desmidiologists (Lenzenweger, 1999) were used for species identification. The iconotype provided in the original description of the newly recorded taxon (Eichler &Gutwiński, 1895) was used. Scientific novelty. The fourth record in the Ukrainian desmidioflora and a new locality in Chernihiv Polesie of a rare taxon from the genus Cosmarium is documented. Previously it was discovered 26 years ago (Palamar-Mordvitseva & Shindanovina, 1998) in Soseske bog nearby Olyshivka village Chernihiv rayon and oblast. This is the first publication of Ukrainian cells microphotographs. Conclusions. All records of this taxon in Ukraine are in Chernihiv Polesie. We hope this publication will provide good illustrative and informative basis for further findings of C. taxichondriforme in other regions of Ukraine. Sampling small water bodies should not be neglected.