Zostera noltei
Chromosome number: 2n = 12 (den Hartog et al, 1987).
Reference: den Hartog, C.; Hennen, J.; Noten, T.M.P.A. & van Wijk, R.J. (1987). Chromosome numbers of the European seagrasses. Plant Systematics and Evolution 156, 55-59.
Morphology similar to the other species of subgenus Zosterella (Z. japonica, Z. muelleri s.l. and Z. capensis), but misidentifications are unlikely as the ranges do not overlap.
In the NE Atlantic, Z. noltei can be confused with the narrow-leaved ecotype of Z. marina (var. angustifolia), but differs in having pronounced 'notches' at the tip of the leaves and open leaf scars. In the Mediterranean, it can also be confused with Cymodocea nodosa, which is easily told apart by its pink rhizomes with one branched root per node, as opposed to typically green to brown rhizomes with multiple roots per node in Z. noltei. The two also differ in their leaf apices, though the differences are only clear when seen under magnification: in C. nodosa, apices are rounded and minutely serrated, while Z. noltei they are notched and lack serration.
NE Atlantic, north to southern Norway and south to Mauritania, as well as the Mediterranean, Black, Azov, and Caspian Seas (Green & Short, 2003). Though it is present in the Skagerrak/Kattegat area, it does not penetrate much into the Baltic proper. It has also been reported from the Aral Sea (Milchakova, 2003), though with few recent records. Some Mediterranean records may be misidentifications of Cymodocea nodosa, particularly in the Levantine Sea.
References:
Milchakova, N.A. (2003). The seagrasses of the Black, Azov, Caspian and Aral Seas. In Green, E.P. & Short, F.T. (2003). World Atlas of Seagrasses. University of California Press.
Green, E.P. & Short, F.T. (2003). World Atlas of Seagrasses. University of California Press.
Sandy or muddy substrates in sheltered environments. Typically intertidal throughout its Atlantic range, but subtidal in areas where tides are not present (e.g. the Mediterranean).
Monoecious, with 4-5 male and female flowers arranged alternately along a spadix. Generative shoots are poorly branched and the spathe is the same colour as the shoots, so inflorescences are easily overlooked.