Valves large, rhombic-lanceolate with a gibbous central region
Pseudosepta present
Proximal raphe ends straight, weakly expanded
Stauros bow-tie shaped
Striae strongly radiate
Stauroneis acuta has large rhombic-lanceolate valves with a gibbous central region, acutely rounded apices with pseudosepta, straight and weakly expanded proximal raphe ends, strongly radiate striae, and a large stauros shaped like a bow tie.