Description of a New Telonemia Genus and Species With Novel Observations Providing Insights Into Its Hidden Diversity.

Telonemia is a fascinating and understudied group of microbial eukaryotes known to have a vast diversity that is still uncharacterized. In fact, although their phylogenetic position is still actively debated, their diversity and biology are largely unexplored: to date, there are only seven described species in three genera, although there are estimated to be hundreds more unknown lineages. Here, we describe the isolation and characterization of two new strains, including a new genus (Hyaliora molinica n. gen. n. sp.) and a new species (Telonema blandense n. sp.), and the re-isolation of a previously characterized telonemid, Telonema subtile, accompanied by new behavioral observations. We present morphological measurements highlighting differences among the isolates and a phylogenetic tree incorporating their 18S rRNA gene sequences. Furthermore, key aspects of their cell biology and structure are highlighted to provide insights into the evolution of their potential sister groups. Since they are relevant not only phylogenetically but also play a crucial role in food webs with some abundant representatives in aquatic ecosystems, the findings of this study provide further sampling and culturing of Telonemia to increase the knowledge of the hidden diversity and evolution of this mysterious group.