Terrestrial flatworms (Platyhelminthes, Tricladida, and Geoplanidae) belong to what
is known as cryptic soil fauna of humid forests and are animals not easily found or
captured in traps. Nonetheless, they have been demonstrated to be good indicators
of the conservation status of their habitat as well as a good model to reconstruct the
recent and old events affecting biodiversity. This is mainly
... [Show full abstract] due to their delicate constitution,
their dependence on the integrity of their habitat, and their very low dispersal
capacity. At present, little is known about their communities, except for some
studies performed in Brazil. In this work, we analyze for the first time in Europe terrestrial
flatworm communities. We have selected two protected areas belonging to
the Red Española de Parques Nacionales. Our aims include performing a first study of
the species richness and community structure for European terrestrial planarian species
at regional and local scale. We evaluate the effect of type of forests in the community
composition and flatworms’ abundance, but also have into account the
phylogenetic framework (never considered in previous studies) analyzed based on
molecular data. We find differences in the species composition among parks, with an
astonishingly high diversity of endemic species in the Parque Nacional de Picos de
Europa and an extremely low diversity of species in the Parque Nacional de Ordesa y
Monte Perdido. These divergent patterns cannot be attributed to differences in physical
variables, and in addition, the analyses of their phylogenetic relationships and, for
a few species, their genetic structure, point to a more probable historical
explanation.
