Cryptonemia seminervis

Range & Status

A medium-sized species with a flattened frond and a distinctive evanescent mid-rib. There are little data available on the habitat of this seaweed in the British Isles, however in Portugal it occurs on exposed sandy rocks in shady places in the upper subtidal and in lower intertidal pools. Known only from the Isles of Scilly (deep water?) and the Channel Isles (unattached).