Écologie Distribution Gestion Impacts Références et liens Contacts

Espèces semblable à Salvinia molesta Cliquez ici pour retourner à l'écologie Salvinia auriculata The shape of the leaves is very variable so it is impossible to distinguish members of the Salvinia auriculata complex by this feature alone. They also all share "egg-beater" shaped flotation hairs on the end of each papillae. They mainly differ in the conformation of sporocarps and the branching system. The main axis of the submerged orgam of S. auriculata divides into two or three slightly reflexed main branches immediately it emerges from the rhizome. Each gives rise to a number of secondary axes that are densely covered with uniseriate multicellular trichomes. At the centre of the curved main aixs there are usually two fertile axes; each sporocarp is pedunclate and the length of the penduncle becomes shorter with each new sporocarp produced; as a consequence the sporocarps hang at about the same level below th plant. The sporocarps are generally globose and not markedly apiculate. S. auriculata has a level of aggressiveness similar to S. molesta and expected to cause similar problems (Mitchell and Thomas 1972; Jacono, 1999). Salvinia biloba The shape of the leaves is very variable so it is impossible to distinguish members of the S. auriculata complex by this feature alone. They mainly differ in the conformation of sporocarps and the branching system. They also all share "egg-beater" shaped flotation hairs on the end of each papillae. Salvinia biloba has a well developed main axis that divides into secondary axes after 3-5mm. The fertile axes have a sporopioid cymose branching system without marked dorsoventrality. Sporocarps are globose, not apiculate, 2-3mm in diameter and contain a high proportion of fertile sporangia. The length of the peduncle is about 3mm but may reach 10mm in length. In comparison, S. molesta has a dorsiventral scorpioid cymose system and the sporocarps are 1mm ovoid, apiculate and contain a high proportion of empty sporangia. The first two spores S. molesta are densely covered with trichomes and contain megasporangia. S. biloba has a level of aggressiveness similar to S. molesta and expected to cause similar problems (Mitchell and Thomas 1972; Jacono, 1999). Salvinia herzogii The shape of the leaves is very variable so it is impossible to distinguish members of the S. auriculata complex by this feature alone. They also all share "egg-beater" shaped flotation hairs on the end of each papillae. They mainly differ in the conformation of sporocarps and the branching system. The submerged organ of Salvinia herzogii has a well developed main axis that divides into secondary axes after 2-5mm, but up to 14mm. Sporocarps are ovid and apiculate with marked apical papillae. S. herzogii has a level of aggressiveness similar to S. molesta and expected to cause similar problems (Jacono, 1999). In 1962 de la Sota described plants in Argentina as a new species, S. herzogii. It had previously been referred to as S. auriculata (Mitchell and Thomas 1972; Jacono, 1999).