Chrysophycean stomatocysts from the Aershan Geological Park (Inner Mongolia), China

Abstract

The Aershan National Geological Park (46–47° 39’ N, 119–121° 28’ E) characterized by volcanic landforms clusters is situated in south-west of the Great Xing’an Mountains. The investigation of chrysophycean stomatocysts was carried out based on sampling five times in this area. 171 morphotypes which were observed using scanning electron microscopy were identified and described in accordance with the guidelines of International Statospore Working Groupm (ISWG), 73 of them are new to science. It is hard to compare the stomatocysts community with that of other areas for the large number of unknown morphotypes, which indicated that amounts of study of stomatocysts morphology should be done in the whole Great Xing’an Mountains.

Biogeography and ecology of freshwater chrysophyte cysts in Finland

“…Our research supports previous studies in which pH was one of the most important variables that controlled the distribution of chrysophytes and their cysts (Duff & Smol, 1991;Carney et al, 1992;Siver, 1995;Duff et al, 1997;Wilkinson & Smol, 1998;Hansen, 2001;Pang & Wang, 2014). The most diverse cyst assemblages have been found in neutral and slightly acidic lakes and ponds, as in most of the lakes in this study (Adam & Mahood, 1981;Hansen, 2001;Pang & Wang, 2014).…”

“…Our research supports previous studies in which pH was one of the most important variables that controlled the distribution of chrysophytes and their cysts (Duff & Smol, 1991;Carney et al, 1992;Siver, 1995;Duff et al, 1997;Wilkinson & Smol, 1998;Hansen, 2001;Pang & Wang, 2014). The most diverse cyst assemblages have been found in neutral and slightly acidic lakes and ponds, as in most of the lakes in this study (Adam & Mahood, 1981;Hansen, 2001;Pang & Wang, 2014). PEARL 86, 11, 16 and 57, found in Finland, seem to be produced by chrysophyte species tolerant of lower-pH environments, which is also backed up by previous studies elsewhere (Rybak et al, 1991;Facher & Schmidt, 1996;Duff et al, 1997;Betts-Piper et al, 2004).…”

“…During recent decades, several cyst floras from different geographical regions have been published, e.g. Central Europe (Facher & Schmidt, 1996), the Azores (Hansen, 2001), the Pyrenees (Pla, 2001), sub-Antarctica (van de Vijver & Beyens, 1997 and China (Pang & Wang, 2014Bai et al, 2018). The most expansive floras are the Atlas of Chrysophycean Cysts and the Atlas of Chrysophycean Cysts Volume II (Wilkinson et al, 2001), focusing largely on North American temperate and Arctic locations.…”