| Encyonema | |
|---|---|
 | |
| Encyonema sp. | |
Scientific classification  | |
| Domain: | Eukaryota |
| Clade: | Sar |
| Clade: | Stramenopiles |
| Phylum: | Ochrophyta |
| Clade: | Diatomeae |
| Class: | Bacillariophyceae |
| Order: | Cymbellales |
| Family: | Cymbellaceae |
| Genus: | Encyonema Kütz., 1833 |
Encyonema is a genus of asymmetric biraphid diatoms belonging to the family Cymbellaceae. [1] This genus is characterized by its curved dorsal edge and ventrally-deflected distal raphe ends. [2] Encyonema contains mostly freshwater species, though there are a few marine exceptions. [2] First described by German phycologist and botanist Friedrich T. Kützing in his 1833 publication "Synopsis diatomearum," this genus has over 400 described specific and infraspecific taxa and new species are still being described today. [3] [4] [5] The genus underwent significant revision in the 1980s and 90s, resulting in the reclassification of multiple species as belonging to Encyonema that were previously grouped in the Cymbella genus. [6] K. Krammer and Round et al. were the first to formally separate Encyonema species from Cymbella, citing differences in raphe orientation as well as striae and plastid structures. [3] [7]
The genus has cosmopolitan distribution, primarily being found in benthic freshwater habitats with low electrolyte content. [1] [3] [8] Many Encyonema species are capable of producing mucilaginous sheaths, with some forming colonies within mucilage tubes. [8] This genus exhibits a broad size range, with species like E. reichardtii being as small as 9.8 x 3.3 µm while others like E. reimeri get as large as 89 x 26.5 µm. [9] [10]
