Carapace hairless. Rostrum slender and long, with 7to 9 teeth on dorsal, and 4 to 6 teeth on ventral margin; blade of rostrum becoming moderately high in large specimens; adrostral crest and groove extending as far as, or just beyond epigastric tooth, the groove shallow; postrostral crest ending distinctly before posterior margin of carapace; gastro-frontal and hepatic crests absent