Nadinella tenella, pseudostome
Nadinella tenella Penard, 1900
I found this single specimen in the river Saar near Saarburg, Germany, in sediment on submerged stones along its shore. It differs from shells found in the Netherlands in having a narrower pseudostome, where the Dutch specimens have a broad oval one.
Pseudostome and collar, with two filopodia
Nadinella tenella, with arrowed collar and pseudostome with 5 filopodia
Plasm visible; it doesn’t fill the shell completely