Deliverable No. 189 Indicator value database for Ephemeroptera ...

Baetis rhodani (Pictet, 1843)
Baetis rhodani is a species widespread distributed in Europe. The preference for flow and substrate
types wase defined based on a datasets build up from Northern and Southern Apennines and from
lowland streams in the Po valley, which only include high/good quality status sites (Buffagni et al.,
2002).
Figure 8. Distribution of Baetis rhodani in riverine habitats with different flow types in High/Good
quality sites in Italian rivers.
Different studies are present in the literature concerning habitat preference for this species (e.g.
Jenkins et al., 1984; Zamora-Muñoz et al., 1993; Bauernfeind & Humpesch, 2001; Buffagni &
Erba, 2002) mostly indicating that the species is ubiquist in terms of both current velocity and
substrate type. Figure 8, which is based on newly processed field data, shows in the form of a
box&whiskers graph the obtained preferences for flow types. B. rhodani can be confirmed as an
ubiquist species, being present in all the considered flow types except the chaotic flow. Highest
median values were observed for the smooth flow.
Figure 9. Distribution of Baetis rhodani in the different substrate micro-habitats in High/Good
quality sites in Italian rivers.
24