Landoltia punctata: a new documented species
Landoltia punctata (Lemnaceae) is a freely floating aquatic species native to South-East Asia and Australia. In the EPPO region L. punctata has been recorded in Italy, Netherlands, Spain and Switzerland. L. punctata reproduces by vegetative budding of the daughter fronds from pouches at the base of each frond. The species can reproduce sexually, by seed, though this is reported to seldomly happen. The species grows well in low oxygen aquatic habitats. Natural dispersal is by water movement and movement by waterfowl or mammals. The plant is reported to have entered into Europe and other areas within its invasive range as a contaminant of the aquatic plant species trade. In the UK, in 2006, L. punctata was recorded as a contaminant in garden centres. The impact of this plant species is currently unknown. L. punctata has the potential to block irrigation systems when the species forms dense mats on water bodies. Due to the uncertainty concerning ecological and economic impacts, at present this species does not warrant inclusion on the EPPO Alert List – instead a mini-datasheet has been prepared and will be published on the EPPO website.
Sources
EPPO website. http://www.eppo.int/INVASIVE_PLANTS/iap_list/data_sheets/15-20550_DS_Landoltia_punctata.doc
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