Video sequence made from the river Arc sample divided into 3 parts: (Clip 1) movement of a 120 µm-long Nitzschia species, (Clip 2) same species with 2 attached Amphora cells. The cell swings from connective to valve side without slowing down (LM ×100). (Clip 3) Nitzchia sigmoidea moving with several Amphora cells attached to its frustule (LM ×200) (Material: Leica DFC290 hd camera on a Leica DM5500B microscope, frame rate=30/s).
Supplement 2
Calculation of conditional probabilities given the observed occurrences of a potential host species in the regional database.