Bioacoustics of Vietelmis jablonskii

Habitat. The holotype was collected in a shallow, meandering tributary stream of the Nam Song River near Nassom village ( Fig. 1 ); sampling was performed in gravel substrate. The paratype specimen from Thailand was collected from the Yakruae Creek ( Fig. 2 ), a second-order unpolluted and shaded stream, ca. 3‒5 m wide, and surrounded by secondary forest. Yakruae Creek has a heterogeneous channel morphology with cobble and gravel deposits, blank bedrock, as well as decaying leaf litter deposits. In general it flows only moderately fast, with slow pool sections, interrupted by riffles and run sections with distinctly higher current velocity. The specimen was retrieved from bottom gravel in a run section ca. 50 m from the Visitor’s Center of Nam Nao National Park. Collecting remarks. In Thailand , Vietelmis jablonskii sp.nov. was collected by using a D-frame dip net to sample the gravel sediments described above (for details on the collection method, see Freitag 2015 ). Although samples were collected monthly, only a single male specimen was found. The species obviously occurs in low densities and is probably rare.