Genus Sclerocyphon

Tasmania has three species listed.  The larvae feed on algae, and can live in fast moving water due to their streamlining.

Pending ID – Sclerocyphon

#1. Early November 2008
Strickland Falls, Ferntree
Found clinging under stones in the Hobart Rivulet.
Photos KE
 

#2. Early November 2012
Strickland Falls, Ferntree
Dorsal and ventral surfaces
Photos KE
 

#3.    5mm
Mid November 2016
New Town Rivulet, Lenah Valley
Dorsal surface
Photos and video KE
   

Ventral Surface

References:
Grove S.J., Forster  L. G. ,Porch, N. (2021) An illustrated checklist of the insects of Tasmania. Part 1 – Coleoptera (beetles). The Royal Society of Tasmania. Hobart