Dercitus bucklandi (Bowerbank, 1858)

Description: This sponge is usually found filling crevices in vertical rock faces. It has the appearance of a black membrane stretched across the back of the crevice.

Habitat: In crevices in vertical and overhanging rock faces, especially on limestone.

Distribution: Known recently from the west and southwest coasts of the British Isles.

Similar Species: This is the only thick black sponge known to be found in the British Isles.

Key Identification Features:

• Black coloration.
• Habit of bridging crevices.

Distribution Map from BioMar data for Ireland - Google Earth map:  download this placemark (not got Google Earth installed?)

Distribution Map from NBN: JNCC MNCR data - Grid map National Biodiversity Network mapping facility, data for UK.