Sellaphora ashinovii Glushchenko, Tseplik, Maltsev, Genkal, Iurmanov & Kulikovskiy, 2025

Tseplik, Natalia, Glushchenko, Anton, Maltsev, Yevhen, Genkal, Sergey, Iurmanov, Anton & Kulikovskiy, Maxim, 2025, Molecular and morphological investigation of Sellaphora ashinovii sp. nov. and Planothidium paisiusii sp. nov. - two new diatom species from Oromia Region, Ethiopia, Phytotaxa 701 (2), pp. 161-176 : 164-166

Sellaphora ashinovii Glushchenko, Tseplik, Maltsev, Genkal, Iurmanov & Kulikovskiy sp. nov. ( Figs 1–25 )

Holotype. Slide no. 05556 (represented here by Figure 13 ), deposited in the Herbarium of K.A. Timiryazev Institute of Plant Physiology , Russian Academy of Sciences (HD), Moscow, Russia, prepared from oxidized culture strain CBMC129 ef.

Isotype. Slide no. 05556a, Herbarium of Addis Ababa University, Addis Ababa, Ethiopia.

Reference strain. CBMC 129ef from the Culture and Barcode Collection of Microalgae and Cyanobacteria “Algabank” (СВМС), isolated from sample E67.

Type locality. Ethiopia, Oromia Region, Lake Langano, periphyton, 1591 m elev., 7°38.85’N 38°49.176’E, leg. B.A. Levin, 15 April 2016. Sample E67.

Description. LM ( Figs 1–18 ). Valves linear-lanceolate with rounded ends. Length 7.4–13.5 μm (11.9 ± 1.6; n=30), width 3.5–4.5 μm (4.0 ± 0.3; n=30). Axial area narrow, weakly expanded towards the central area. Central area bowtie-shaped, formed by 3–4 shortened striae on each side. Raphe filiform. Striae weakly radiate, 24–26 in 10 μm.

SEM. External views ( Figs 19–21 ). Valve face slightly convex. Raphe weakly lateral. Central raphe ends slightly expanded. In the initial valves, distal raphe ends terminate on valve face. One of the distal raphe ends is curved, the other is almost straight. Striae uniseriate. Shortened intercalary striae and short striae on the valve apices are present. Areolae small, rounded, ca. 70 in 10 μm.

SEM. Internal views ( Figs 22–25 ). Raphe branches almost straight, filiform. Central raphe ends weakly unilaterally deflected. Distal raphe ends terminating in small helictoglossae. Shortened intercalary striae present. Areolae covered by individual hymenes.

Sequence data. Partial 18S rDNA gene sequence comprising V4 domain sequence (GenBank accession number PV383267) and partial rbc L sequence (GenBank accession number PV384976) for the strain CBMC129ef.

Etymology. This species is named after Nikolay Ivanovich Ashinov (1859–1902), a renowned Russian Cossack chieftain and traveler in Africa, who made significant contributions to the development of Russia-Abyssinia relations. He was also an amateur linguist who published the book “The Abyssinian alphabet and the initial Abyssinian-Russian dictionary”.

Distribution. As yet known only from the type locality.

Molecular study. S. ashinovii sp. nov. forms an independent branch on the phylogenetic tree ( Fig. 26 ) that is sister to strains of Sellaphora minima (Grunow) D.G. Mann in Round et al. (1990: 552). These strains are part of a larger clade that also includes Sellaphora seminulum (Grunow) D.G. Mann (1989: 2) and S. terrestris Glushchenko, Kezlya, Maltsev & Kulikovskiy in Glushchenko et al. (2022: 2).

Figures

FIGURE 26. Phylogenetic position of Sellaphora ashinovii sp. nov. (indicated in bold) within the Sellaphoraceae based on Bayesian inference for a concatenated alignment of 44 partial rbcL and partial 18S rDNA sequences. The total length of the alignment is 1,117 characters. Values above the horizontal lines are bootstrap support from ML analyses (<50 are not shown); values below the horizontal lines (or to the right of the slash) are Bayesian posterior probabilities (<0.9 are not shown). Strain numbers (if available) and GenBank numbers are indicated for all sequences.

FIGURES 1–4. Sellaphora ashinovii sp. nov. LM, DIC. Sample of wild population, size diminution series. Scale bar = 10 μm.

FIGURES 5–18. Sellaphora ashinovii sp. nov. LM, DIC. Slide no. 05556 from oxidized culture, strain CBMC129ef. Holotype represented by fig. 13. Scale bar = 10 μm.

FIGURES 19–21. Sellaphora ashinovii sp. nov. SEM, external views. Oxidized culture, strain CBMC129ef. Whole valves. Scale bars = 2 µm.

FIGURES 22–25. Sellaphora ashinovii sp. nov. SEM, internal views. Oxidized culture, strain CBMC129ef. Figs 22, 23. Whole valves. Fig. 24. Central area. Fig. 25. Valve end. Scale bars = 2 µm.