Pinnularia subaltiplanensis Zidarova & Kopalová & Vijver 2012, sp. nov.

• Main Authors: Zidarova, Ralitsa, Kopalová, Kateŕina, Vijver, Bart Van De
• Format: Other/Unknown Material
• Language: unknown
• Published: 2012
• Subjects: Biodiversity; Taxonomy; Chromista; Bacillariophyta; Bacillariophyceae; Naviculales; Naviculaceae; Pinnularia; Pinnularia subaltiplanensis; Hurd; Hurd peninsula; Livingston Island; Sickle; South Shetland Islands
• Online Access: https://zenodo.org/record/4929561; https://doi.org/10.5281/zenodo.4929561

Pinnularia subaltiplanensis sp. nov. (Figs 29–35) Valvae lineares ad angustissime lanceolatae, marginibus parallelis ad leviter convexis. Apices in speciminibus maioribus leviter protractae, late subrostratis, in speciminibus minorobus late rotundatae. Longitudo 21–28 µm, latitudo 3.6– 4.5 µm. Area axialis angusta, linearis, non dilatans in aream centralem. Area centralis formans fasciam latam, aliquando asymmetricam. Raphe filiformis, ramis rectis, terminationibus raphis proximalibus unilateraliter leviter deflexis cum, extensis in aream centralem. Terminationes raphis distales paene non discernandae in LM, falcatae. Striae leviter ad moderate radiatae in media parte valvae, convergentes ad apices, 16–19 in 10 µm. Lineae speciosae longitudinales nullae. Valves linear to narrowly lanceolate with parallel to slightly convex margins. Apices in larger specimens slightly protracted and broadly subrostrate, in smaller valves clearly broadly rounded. Valve dimensions (n=10): length 21–28 µm, width 3.6–4.5 µm. Axial area narrow, linear, almost not slightly widened towards the valve middle. Central area forming a large, occasionally asymmetrical, fascia, about ¼ to ⅓ of the valve length. Raphe straight with weakly deflected proximal endings, extending well beyond the last central striae, terminating in clearly expanded central pores, moderately distantly spaced. Distal raphe fissures barely visible, probably sickle-shaped. Striae weakly to moderately radiate near the centre, convergent at the apices, 16–19 in 10 µm. Longitudinal lines not visible in LM. Type:— Hurd Peninsula, Livingston Island, South Shetland Islands, sample A24/2006, leg. R. Zidarova, coll. date 27/12/2005, slide no. BR-4261 (holotype BR), slide PLP-206 (isotype University of Antwerp, Belgium), slide ZU8/27 (isotype BRM). Habitat:— The largest population of P. subaltiplanensis was observed on Hurd Peninsula where the species was found in low abundances in a small brook flowing out from a shallow lake with a low specific conductance (58 ...