DISSEMINATION
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DISSEMINATION |
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| Kingdom | Plantae | 
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| Phylum | Rhodophyta | |
| Class | Rhodophyceae | |
| Order | Bangiales | |
| Family | Bangiaceae | |
| Genus | Phorphyra | |
| Species | leucosticta | |
| Classification | Thuret, 1863 | |
| Common name | laver |
| Geographic Range | north-eastern Atlantic (Iceland, Norway, Baltic Sea, Holland, Ireland, Britain, France, Portugal, Azores, Madeira, Canary Islands), Mediterranean Sea (Spain, Corsica, Adriatic, Greece, Egypt, Tunisia). |
| Physical Characteristics | deep dark red rhodophyta; it has a very thin laminar thallus, exclusively lanceolate but not pointed; it is never branched. It has dimensions ranging from few centimetres up to 60 centimeters when it vegetates in eutrophicated waters in the lagoon channels. Its margin is sometimes whitish when the laver is fertile. It has cells which have a rayed pigmentation formation, called chromatophore, and in the centre a pyrenoid, another cytoplasm formation belonging to the plastids, the organelles involved in the photosynthesis. It is formed from a basal disc attached to the substrate, leaves are reddish-brown, ribbon-like, made up of one layer of cells. |
| Notes | it has its maximum development at the end of winter and in spring. Asexual reproduction occurs by spores. In the life cycle the succession of two different generations occurs: the gametophyte, represented by the weed found on the solid substrata, and the sporophyte which is a microscopic filament. |
| Habitat | it is almost always, if not even constantly epiphyte, on other weeds of the upper littoral level and therefore it bears rather well long uncovering due to syzygy low tides. |
| Food habits | it is an autotrophous weed. |
| Status in the lagoon | it is found in every sea and lagoon resorts and also in the resorts with waters purer than the sea such as in the historical town centres of Chioggia and Venice. |
| Sources | |
| References | Le alghe della Laguna di Venezia - Distribuzione,
raccolta, conservazione ed osservazione, di Bruno La Rocca University of California - Santa Cruz, Biological Sciences Course Materials |
| Web References | http://www.terranea.it/personali/alghe/present.htm
http://bio.classes.ucsc.edu/ |
| Source of the photo | http://www.horta.uac.pt/ |
Porphyra
leucosticta
