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

• Main Authors: Zidarova, Ralitsa, Kopalová, Kateŕina, Vijver, Bart Van De
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2012
• Subjects: Biodiversity; Taxonomy; Chromista; Bacillariophyta; Bacillariophyceae; Naviculales; Naviculaceae; Pinnularia; Pinnularia microstauroides; Livingston Island; South Shetland Islands
• Online Access: https://doi.org/10.5281/zenodo.4929567; http://treatment.plazi.org/id/03F2686FFF9D925442EBF96AFC529467

Pinnularia microstauroides sp. nov. (Figs 102–125) Valvae lineares marginibus plerumque undulatis, parallelis ad leviter convexis, apicibus late rotundatis, leviter protractis, rostratis ad subcapitatis. Longitudo 26–50 µm, latitudo 5.3–6.7 µm. Area axialis moderate lata, lanceolata, dilatans in aream centralem. Area centralis formans fasciam angustam ad moderate latam, rhomboidem, asymmetricam. Raphe filiformis, ramis leviter curvatis. Terminationes raphis proximales leviter unilateraliter deflexae cum poris expansis, guttiformibus. Fissurae raphis distales falcatae. Striae moderate radiatae in media parte valvae, convergentes ad apices, 12–14 in 10 µm. Lineae speciosae longitudinales nullae. Valves linear with usually undulating, parallel to weakly convex margins and weakly protracted, rostrate to subcapitate, broadly rounded apices. Larger specimens with undulated margins. Valve dimensions (n=25): length 26–50 µm, valve breadth 5.3–6.7 µm. Axial area relatively large, lanceolate, widening toward the central area. Central area forming a narrow to moderately broad, rhomboid, usually asymmetrical fascia. Striae gradually becoming shorter towards the valve middle. Raphe filiform with slightly curved raphe branches. Proximal raphe endings clearly deflected with expanded droplike pores. Terminal fissures distinct, sickle-shaped. Striae moderately radiate in the middle, convergent at the ends, 12–14 in 10 µm. Longitudinal lines absent Type:— Byers Peninsula, Livingston Island, South Shetland Islands, sample BY003, leg. B. Van de Vijver, coll. date 09/01/2009, slide no. BR-4262 (holotype BR), slide PLP-207 (isotype University of Antwerp, Belgium), slide ZU8/24 (isotype BRM). Habitat:— Pinnularia microstauroides was frequently observed in larger lakes on Byers Peninsula and only occasionally on Hurd Peninsula, where it was previously reported from as P. microstauron var. rostrata Krammer (Zidarova 2008: 30, fig. 27). The largest populations were found in coastal lakes on Byers Peninsula with a higher specific ...