Abstract
In this article we describe Nitzschia anatoliensis Górecka, Gastineau & Solak sp. nov., an example of a diatom species inhabiting extreme habitats. The new species has been isolated and successfully grown from the highly alkaline Van Lake in East Turkey. The description is based on morphology (light and scanning electron microscopy), the sequencing of its organellar genomes and several molecular phylogenies. This species could easily be overlooked because of its extreme similarity to Nitzschia aurariae but molecular phylogenies indicate that they are only distantly related. Furthermore, molecular data suggest that N. anatoliensis may occur in several alkaline lakes of Asia Minor and Siberia, but was previously misidentified as Nitzschia communis. It also revealed the very close genetic proximity between N. anatoliensis and the endosymbiont of the dinotom Kryptoperidinium foliaceum, providing additional clues on what might have been the original species of diatoms to enter symbiosis.
Highlights
Based on morphological comparisons with similar species, but above all the use of several molecular markers, it is clear that the strain from Van Lake is a new species, Nitzschia anatoliensis
It is among the few diatom species able to live in the waters of Van Lake (Gessner, 1957)
The Maximum Likelihood (ML) phylogeny inferred from the nuclear SSU gene recovered N. anatoliensis with three strains of N. communis (KM387717, KM387718 and KM387719) but discriminated it from two others (AJ867014 and AJ867278) yet with low bootstrap values
Summary
Nitzschia A.H. Hassall 1845 is the most speciose genus within the diatom family Bacillariaceae Ehrenberg and is regarded as one of the most speciose among diatoms in general. The two largest data bases on taxonomy and species richness, WORMS and Algaebase, provide a number of species for Nitzschia well exceeding 1,000. WORMS lists 1,495 taxa (Kociolek et al, 2018), while Algaebase lists 1,284 species and 442 infraspecific names (Guiry & Guiry, 2019), with 842 flagged as accepted taxonomically. It is difficult to standardize Nitzschia morphology in terms of valve outline, numerous species represent one of the following shapes: (a) narrow, straight or narrow sigmoid; (b) narrow linear; (c) lanceolate or (d) elliptic, with usually uniseriate striae. Nov., a cryptic diatom species from the highly alkaline Van Lake (Turkey).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
