A scientific study detects the presence of tropical exotic planarians in the Iberian Peninsula
A study published in the journal PeerJ alerts that there are at least ten introduced exotic land planarian species from Australia, New Zealand, Asia and South America in the Iberian Peninsula. The article is signed by experts Marta Riutort, Marta Álvarez Presas and Àngels Tudó, from the Department of Genetics and the Biodiversity Research Institute (IRBio) of the University of Barcelona (UB), Eduardo Mateos, from the Department of Animal Biology of UB, and Hugh Jones, from the Natural History Museum of the United Kingdom.
A study published in the journal PeerJ alerts that there are at least ten introduced exotic land planarian species from Australia, New Zealand, Asia and South America in the Iberian Peninsula. The article is signed by experts Marta Riutort, Marta Álvarez Presas and Àngels Tudó, from the Department of Genetics and the Biodiversity Research Institute (IRBio) of the University of Barcelona (UB), Eduardo Mateos, from the Department of Animal Biology of UB, and Hugh Jones, from the Natural History Museum of the United Kingdom.
Exotic planarian: potentially invasive species that spread easily
Terrestrial planarians are flatworms of the phylum Platyhelminthes with a cosmopolitan distribution. Some planarians from tropical latitudes —larger and more coloured than native ones— were introduced in Europe and North America. Tropical planarians detected in Europe are a potential risk to invertebrate soil fauna, native land planarians and some vertebrate species with the same feeding habits (particularly, birds and small mammals).
Experts explain that “planarian invasion might cause significant economic losses in agriculture and damage to the ecosystem. To be exact, the planarian Arthurdendyus triangulatus, native from New Zealand and common in Scotland, feeds on earthworm populations and, consequently, alters natural ecosystems and agricultural conditions (soil oxygen deficiency, inadequate drainage, inundation of agricultural land, etc.)”.
There was only one introduced exotic planarian in the Iberian Peninsula some time ago
The tropical planarian Bipalium kewense, native from Southeast Asia and characterized according to the samples found in Kewʼs gardens (London), was the only species detected in the Iberian Peninsula until 2007. To date, four other introduced species have been identified in the Iberian Peninsula.
The new study developed by the UB research group alerts that there are at least 10 potentially invasive planarian species in the Iberian Peninsula. Through morphological and phylogenetic molecular analyses, and by inferring phylogenetic relationships with species from their native origins, the group identified the exotic species that inhabit different places such as gardens, plant nurseries, garden centres and recently restored areas.
More restrictive rules on the trade of plants
In the case of the invasive planarian Caenoplana coerulea, a native species from Australia which has spread rapidly, the UB research group used geographic information systems and ecological niche modelling to study its potential distribution in the Iberian Peninsula and its risk of introduction in natural areas.
Authors affirm that “everything points out that Caenoplana coerulea is becoming naturalized in studied restored areas. International plant trade is the source of these animals, and many garden centres are acting as reservoirs. We visit some centres in which we found up to six different species”.
Researchers point out that habitat restoration works —in most cases include plant species plantations from plant nurseries in places such as road slopes— have facilitated the introduction of Caenoplana coerulea near forests and agricultural fields. “There is a need to take measures on plant trade and to have special care in the treatment of restored habitats”, highlight UB experts.