Hannaea tibetiana Q.Liu, Glushchenko, Kulikovskiy & Kociolek, 2019

Liu, Qi, Glushchenko, Anton, Kulikovskiy, Maxim, Maltsev, Yevhen & Kociolek, John Patrick, 2019, New Hannaea Patrick (Fragilariaceae, Bacillariophyta) species from Asia, with comments on the biogeography of the genus, Cryptogamie, Algologie 20 (5), pp. 41-61 : 43

publication ID	https://doi.org/ 10.5252/cryptogamie-algologie2019v40a5
DOI	https://doi.org/10.5281/zenodo.7818968
persistent identifier	https://treatment.plazi.org/id/03DF8792-EB63-4460-6ACC-4F7EFB47FC78
treatment provided by	Felipe
scientific name	Hannaea tibetiana Q.Liu, Glushchenko, Kulikovskiy & Kociolek
status	sp. nov.

Treatment

Hannaea tibetiana Q.Liu, Glushchenko, Kulikovskiy & Kociolek , sp. nov.

( Figs 1-3 View FIG View FIG View FIG )

HOLOTYPE. — Slide no 201507029-1; illustrated in Fig. 1H View FIG in collection at Qi Liu of the Freshwater Algal Herbarium of Shanxi University ( SXU).

TYPE LOCALITY. — China, Midui Glacier, Tibet, unnamed river, periphyton, (N29°87.684’, E96°29.678’).

ETYMOLOGY. — The specific epithet “ tibetiana ” refers to the name of the region where this species was observed.

DISTRIBUTION. — As yet known only from the type locality.

DESCRIPTION

Valves

Asymmetrical about the apical axis, lunate to almost rectangular, with capitate to bent-capitate apices, length 22-43 µm, breadth 15-18 µm (n=45).

Central sternum

Distinct to indistinct, with striae parallel to slightly radiate, 16-18/10 µm.

Bent apices

Deflected towards the ventral margin.

The concave valve

May bear an unilaterally-positioned unornamented area on the concave margin of the valve in the center, slightly tumid to undifferentiated.

SEM, external views ( Fig. 2 View FIG )

The exterior of the valve can be seen to have a distinct central sternum, with heavily silicified ridges perpendicular, extending across the valve face ( Fig. 2A, B View FIG ). Striae uniseriate, comprised of small, rounded areolae ( Fig. 2 View FIG A-C), that extend onto the valve mantle ( Fig. 2C, D View FIG ). Areolae number 85-90 /10 µm within a stria. Cingulum comprised of numerous bands ( Fig. 2E View FIG ). At one apex some striae can extend the central sternum, and even be oriented along the apical axis of the valve ( Fig. 2F View FIG ). An elongated opening at one end of the valve is the external expression of the single rimoportula. Ocellimbi are present at each apex, positioned on the valve mantle ( Fig. 2G View FIG ).

SEM, internal views ( Fig. 3 View FIG ):

The central sternum is narrow, and striae are positioned alternatively on each side ( Fig. 3A, B View FIG ). At one apex there is no rimoportula ( Figs 3A, C View FIG ), at the other a rimoportula is present ( Fig. 3A, D View FIG ). The rimoportula is comprised of two thickened strips of silica on either side of a slit-like opening ( Fig. 3D View FIG ). At the apices striae may extend across the central sternum. Small, square-shaped porelli comprise the ocellimbi on the mantle of each apex ( Fig. 3C, D View FIG ).