Length 9-13 mm. Body very slender (Streetsia steenstrupi 1). Head not shorter than third length of whole animal. ART 5 of P II expanded distally, posterodistal process pointed, triangular, directed forward, almost reaching base of dactyl, anterior margin finely serrate in distal part, smooth in proximal part, with fine setae; article 6 narrowly oval, posterior margin with fine setae. ART 2 of P VI with posterior margin strongly convex proximally, both margins slightly produced distally; ART 4 with small pointed processes in distal part of posterior margin. Epimeral plates with sharp posteroventral corners, straight ventral margins. Fused (II+III) urosomite twice as long as wide. Telson with produced sharp top.