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The chrysophyte genus Dinobryon Ehrenberg consists of 44 taxa, which occur in freshwaters, rarely marine waters, mostly in temperate regions of the world. The taxa of Dinobryon produce characteristic solitary or dendroid colonies and resting stages called stomatocysts. Only 20 Dinobryon taxa have information on produced stomatocysts and only four stomatocysts are reliably linked with vegetative stages using modern identification standards employing scanning electron microscopy (SEM) analyses. In this study, an encysted material of Dinobryon pediforme (Lemmermann) Steinecke was collected in two lakes in contrasting regions of Poland. Light microscopy (LM) and scanning electron microscopy (SEM) analyses revealed that Dinobryon pediforme produces stomatocyst #61, Piątek J. that is described here as new morphotype following the International Statospore Working Group (ISWG) guidelines. This raises to five the number of reliable links between vegetative stages of Dinobryon species and corresponding stomatocysts. Phenotypic similarities between Dinobryon species and their stomatocysts, analysed for five reliably established links, showed no relationships in size and shape between loricas and stomatocysts belonging to the same species. The morphological characters of loricas and stomatocysts mapped onto the phylogenetic tree of the five Dinobryon species revealed only little congruence between their morphology and phylogenetic relationships. [ABSTRACT FROM AUTHOR]

An account is given of chrysophycean stomatocysts and algae occurring together with the carnivorous plants known as bladderworts, Utricularia intermedia, U. minor and U. australis, in the peat bog of Jeleniak-Mikuliny Nature Reserve. Eleven chrysophycean stomatocyst morphotypes were found, all reported for the first time from this nature reserve. Among them, two are new records for Europe (stomatocysts 330 and 208) and another two are new for Poland (stomatocysts 112 and 387). Descriptions are provided together with SEM illustrations. General data about cyanobacteria and eukaryotic algae occurring with these stomatocysts are enumerated. [ABSTRACT FROM AUTHOR]

An assemblage of chrysophycean stomatocysts from the recent sediments of a thermo-mineral spring in Ain Sukhna in Egypt was investigated using scanning electron microscopy. Seven stomatocysts are reported from the spring; four are described as new morphotypes, and three have previously been observed in various parts of the world. A new term, 'ornamentation with bullate swellings,' is introduced to describe a type of ornamentation not observed to date in any known stomatocysts. The present study documents for the first time an assemblage of chrysophyte stomatocysts from Africa in a unique ecosystem consisting of a thermal, highly mineralized spring. [ABSTRACT FROM AUTHOR]