Skeletonema pseudocostatum Zingone & Sarno
- Dataset
- GBIF Backbone Taxonomy
- Rank
- SPECIES
Classification
- kingdom
- Chromista
- phylum
- Ochrophyta
- class
- Bacillariophyceae
- order
- Thalassiosirales
- family
- Skeletonemaceae
- genus
- Skeletonema
- species
- Skeletonema pseudocostatum
description
Figs 18 – 22 References: Medlin et al. 1991, p. 522; Sarno et al. 2005, p. 162, figs 7, A – I; Gu et al. 2012, p. 254, figs 21 – 23; Hernández-Becerril et al. 2013, p. 81, figs 16 – 25. Description: Chains are relatively long and straight (slightly curved), with 4 – 9 cells per chain (Figs 18, 19). Cells have two chloroplasts (Fig. 18). The valves are flat to slightly convex, with a relatively high valve mantle (Figs 19 – 21). The areolae are almost quadrangular to rectangular on the valve face and become pseudoloculate near the mantle (Figs 20 – 22). Apart from the observations of the valvocopula, with longitudinal elongate poroids and ribs (Figs 20 – 22), other copulae were not seen in detail. All fultoportulae are open (Figs 20, 21), although some IF’s and TF’s have their bases closed and are more tubular (Figs 20, 22), and the tips of TF’s have a long, very characteristic spine (Fig. 21, small arrows). Each IF fuses to one or, less commonly, two of the sibling valves (Figs 19, 20). Terminal rimoportula locates close to the margin, and has a long tube, with a slightly inflated tip (Figs 21, 22, arrows), whereas the IR is marginal, but very short. Measurements: cell diameter 6.4 – 9.2 μm, areolae density 33 – 40 in 10 μm (Table 1).