This relatively rare diatom with greatly elongated valves has longitudinal ribs running the length of the valve. Its valves are chambered. The apical striae have small circular scattered areolae as opposed to the elongated regular areolae that by light microscopy look like stripes in the chambers of the rest of the valve faces. This diatom is a marine epiphyte. Mucilogenous secretions arise from the apices which allow attachment to the substrate or to form branching colonies. It has only recently been placed in its own genus, previously classified as a synedra. An interesting fact about this diatom is that it is resistant to poisoning by arsenic. This slide also contains a specimen of Coscinodiscus asteromphalus.
