Stigmagloia cyclops (Voigt) Glushchenko, Kezlya, Kapustin & Kulikovskiy, 2024

Kezlya, Elena, Glushchenko, Anton, Kapustin, Dmitry, Maltsev, Yevhen, Nhu, Hai Doan- & Kulikovskiy, Maxim, 2024, Stigmagloia lobbanii gen. et sp. nov. (Bacillariophyceae, Mastogloiales), a new stigma-bearing diatom genus separated from Mastogloia, Phytotaxa 677 (1), pp. 49-65 : 56-58

Stigmagloia cyclops (Voigt) Glushchenko, Kezlya, Kapustin & Kulikovskiy , comb. nov.

Basionym: Mastogloia cyclops Voigt 1942 . J. Roy. Micr. Soc., ser. 3. 62: 8, Pl. 2: fig. 8 (non Mastogloia cyclops sensu auct. post.)

Phylogenetic analysis

The Mastogloia strains form a clade with Aneumastus with high statistical support (PP 0.93). Moreover, all Aneumastus strains form a well-supported subclade (PP 1), while Mastogloia strains are quite distant from each other and form separate branches within the Mastogloia / Aneumastus clade ( Fig. 44 ). The S. lobbanii sp. nov. SVN638 strain forms an independent branch near Mastogloia recta .

The p -distance matrix showed that S. lobbanii sp.nov. has low similarity values with other strains of Mastogloia (p -distance for V4 SSU region 67.76–91.09%, for rbc L region 89.34–92.89% ( Tables 1, 2)). Overall, sequence percent similarity between Mastogloia strains for the V4 SSU rRNA region is 55.49 –95.16%, for rbc L 88.31–93.66%.

The sequence similarity of Mastogloia strains with phylogenetically close Aneumastus species varies within the range 64.49–97.29% for V4 SSU region and 87.3–95.0% for rbc L region. Interestingly, the sequence similarity between the genera Mastogloia and Aneumastus is higher than that observed when comparing Mastogloia strains with each other pairwise. Average similarity value in pairwise comparison of sequences:

• for V4 SSU region

Mastogloia / Mastogloia – 79.13%

Mastogloia / Aneumastus – 87.3%,

• for rbc L region

Mastogloia / Mastogloia – 90.71%

Mastogloia / Aneumastus – 92.61% ( Table 1, 2).

Figures

FIGURE 44. Phylogenetic position of the new Stigmagloia genus (indicated in bold) based on Bayesian inference for the partial rbcL and SSU rRNA genes with 64 sequences.The total length of the alignment is 1384 characters. Posterior probabilities (PP) from BI (constructed by Beast) are presented on the nodes in order. Strain numbers are indicated for all sequences.