Fig 6 - uploaded by Sophie Steinhagen
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Morphology of Blidingia sp. 2. Typical habitat of Blidingia sp. 2 at the German peninsula Nordstrand (A & B). Individuals were found growing in patches and turfs on wooden piles (A) and stones of breakwaters (B). The thalli were unbranched in the middle and apical thallus region (C & D); however, branching in the basal parts was observed infrequently (E). Cells of the basal part proceeded in clear and distinct longitudinal rows (F), but the arrangement of cells is disturbed in the middle and apical thallus parts, and no clear structure was observed (G). Cells were quadratic to polygonal with rounded corners, and the chloroplast was found to be parietal or cell filling and one central pyrenoid was observed (H). -Photos by S. Steinhagen.
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In temperate and subarctic regions of the Northern Hemisphere, green algae of the genus Blidingia are a substantial and environment-shaping component of the upper and mid-supralittoral zones. However, taxonomic knowledge on these important green algae is still sparse. In the present study, the molecular diversity and distribution of Blidingia speci...
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... collection and sample preparation. -Sites along the North Sea and Baltic Sea coasts of Schleswig-Holsteinincluding the island of Helgoland -were repeatedly visited in the years (see also Steinhagen & al., 2019a). In 2016, sampling also covered the heavily trafficked Kiel Canal, which connects both sea areas (Fig. 1, sites 14-16, see also Steinhagen & al., 2019b). Upper littoral and supralittoral zones were checked for macroalgal growth with a focus on freshwater inflows (e.g., drainages, river inflows, beach showers). Several sites were re-visited in the years 2018 and 2019, to verify the presence of populations and obtain material for cultivation (Table 1). ...
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... not present in the Baltic Sea. It inhabited the upper supralittoral zone and was found growing as turfs, but more often it was observed as small patches on stones, concrete, wooden piles or other hard substrates (Fig. 6A,B). When growing epiphytic on macrophytobenthic species (e.g., Fucus spp.), Blidingia sp. 2 did not cover the host like B. marginata. Instead, single individuals were found to be scattered across the host ...
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... thalli of Blidingia sp. 2 were mostly only few millimetres long (rarely taller than 1 cm) and 50-300 μm wide (single individuals had broader thalli up to 700 μm) (Fig. 6C-E). No branches in the middle or apical thallus parts were observed, however the base sometimes exhibited branches (Fig. 6D,E). Thalli were most often compressed, but inflated individuals were also present. Whereas cells form clear and distinct longitudinal rows in the basal thallus parts (Fig. 6F), the arrangement of cells is less ...
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... thalli of Blidingia sp. 2 were mostly only few millimetres long (rarely taller than 1 cm) and 50-300 μm wide (single individuals had broader thalli up to 700 μm) (Fig. 6C-E). No branches in the middle or apical thallus parts were observed, however the base sometimes exhibited branches (Fig. 6D,E). Thalli were most often compressed, but inflated individuals were also present. Whereas cells form clear and distinct longitudinal rows in the basal thallus parts (Fig. 6F), the arrangement of cells is less organised in the middle and apical thallus parts (Fig. 6G). Cells were of various shapes, quadratic to polygonal with rounded ...
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... individuals had broader thalli up to 700 μm) (Fig. 6C-E). No branches in the middle or apical thallus parts were observed, however the base sometimes exhibited branches (Fig. 6D,E). Thalli were most often compressed, but inflated individuals were also present. Whereas cells form clear and distinct longitudinal rows in the basal thallus parts (Fig. 6F), the arrangement of cells is less organised in the middle and apical thallus parts (Fig. 6G). Cells were of various shapes, quadratic to polygonal with rounded corners, 4-8 μm long and 4-6 μm wide in surface view. No thickened cell walls, nor any lamellar internal structures were observed. The chloroplast was parietal or filled the ...
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... thallus parts were observed, however the base sometimes exhibited branches (Fig. 6D,E). Thalli were most often compressed, but inflated individuals were also present. Whereas cells form clear and distinct longitudinal rows in the basal thallus parts (Fig. 6F), the arrangement of cells is less organised in the middle and apical thallus parts (Fig. 6G). Cells were of various shapes, quadratic to polygonal with rounded corners, 4-8 μm long and 4-6 μm wide in surface view. No thickened cell walls, nor any lamellar internal structures were observed. The chloroplast was parietal or filled the cell, with one central pyrenoid (Fig. ...
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... of cells is less organised in the middle and apical thallus parts (Fig. 6G). Cells were of various shapes, quadratic to polygonal with rounded corners, 4-8 μm long and 4-6 μm wide in surface view. No thickened cell walls, nor any lamellar internal structures were observed. The chloroplast was parietal or filled the cell, with one central pyrenoid (Fig. ...
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... addition to the above-mentioned molecular differences of Blidingia sp. 2 and B. marginata, distinctive morphological delimitations of the two entities were also observed. Blidingia sp. 2 differed from specimens of B. marginata (Fig. 3) (Bli- ding, 1963;Kornmann & Sahling, 1978) in generally exhibiting smaller thalli and being mostly unbranched (Fig. 6). Only few individuals exhibited macroscopic branching in the basal thallus parts, and no microscopic branches were observed (Fig. 6). Concurrently, the morphological features of adult Blidingia sp. 2 (Fig. 6) showed high similarity with both the type description of B. minima (Kützing, 1849;Kylin, 1949) and traits described for B. ...
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... of the two entities were also observed. Blidingia sp. 2 differed from specimens of B. marginata (Fig. 3) (Bli- ding, 1963;Kornmann & Sahling, 1978) in generally exhibiting smaller thalli and being mostly unbranched (Fig. 6). Only few individuals exhibited macroscopic branching in the basal thallus parts, and no microscopic branches were observed (Fig. 6). Concurrently, the morphological features of adult Blidingia sp. 2 (Fig. 6) showed high similarity with both the type description of B. minima (Kützing, 1849;Kylin, 1949) and traits described for B. chadefaudii (Kornmann & Sahling, 1978) from ...
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... of B. marginata (Fig. 3) (Bli- ding, 1963;Kornmann & Sahling, 1978) in generally exhibiting smaller thalli and being mostly unbranched (Fig. 6). Only few individuals exhibited macroscopic branching in the basal thallus parts, and no microscopic branches were observed (Fig. 6). Concurrently, the morphological features of adult Blidingia sp. 2 (Fig. 6) showed high similarity with both the type description of B. minima (Kützing, 1849;Kylin, 1949) and traits described for B. chadefaudii (Kornmann & Sahling, 1978) from ...
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