Staurosirella jonssoniana Van de Vijver & Iris Hansen 2024, sp. nov.

• Main Authors: Van de Vijver, Bart, Peeters, Valérie, Hansen, Iris, Ballings, Petra, de Haan, Myriam
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2024
• Subjects: Biodiversity; Taxonomy; Chromista; Ochrophyta; Bacillariophyceae; Fragilariales; Fragilariaceae; Staurosirella; Staurosirella jonssoniana; Iceland
• Online Access: https://doi.org/10.5281/zenodo.11404254; http://treatment.plazi.org/id/919F6EC7C0C7556CA07B66D70417FE17

Staurosirella jonssoniana Van de Vijver & Iris Hansen sp. nov. Fig. 5 Holotype. BR- 4843 (Meise Botanic Garden, Belgium). Fig. 5 H represents the holotype. Isotype. Slide 445 (University of Antwerp, Belgium). Registration. http://phycobank.org/104536. Type locality. Grenlækur, southern Iceland, sampling site at Græntorfa, 63 ° 43.96 ' N, 17 ° 58.07 ' W, coll. date 03 Jul. 2017, leg. Iris Hansen. Description. LM (Fig. 5 A – U). Valves isopolar to weakly heteropolar, lanceolate with convex margins, and narrowly protracted, rostrate apices. Smallest valves almost elliptical (Fig. 5 T – U). Valve dimensions (n = 25): length 6–15 µm, width 3.0–3.5 µm. Sternum narrow, linear. Striae alternating, almost parallel to very slightly radiate in the middle, more strongly radiate towards the apices, 12–13 in 10 µm. Areolae not discernible in LM. SEM (Fig. 5 V – Y). External valve face weakly undulating with slightly raised virgae and striae sunken in ‘ punch hole-like’ depressions (Fig. 5 V – X). Striae extending without interruption from valve face onto the mantle (Fig. 5 X), gradually narrowing towards the sternum (Fig. 5 V – X) giving the striae a lanceolate appearance. Striae uniseriate, composed of long, slit-like, linear areolae, running parallel to the apical axis (Fig. 5 V – X). Vimines very thin, not raised. Marginal spines very obvious, one per virga, each located in a shallow, pit-like depression (Fig. 5 V – X). Apical pore fields absent, replaced by one or two spines. Internally, striae distinctly sunken between the flat, doubly flared virgae and sternum (Fig. 5 Y). Areolae occluded by irregularly shaped volae, extending from the longer inner side of each vimen (Fig. 5 Y). Etymology. The new species honours our friend and colleague Gunnar Steinn Jónsson (Reykjavik, Iceland) in recognition of his important contributions to the diatom research in Iceland. Distribution. Staurosirella jonssoniana has so far only been found in Iceland. Ecology and associated diatom flora. The type locality, Grenlækur, is a small ...