Description of biotope or habitat type
Verrucaria maura on littoral fringe rock
Habitat (physical) description
|Salinity||Full (30-35 ppt), Variable (18-35 ppt)|
|Wave exposure||Very exposed, Exposed, Moderately exposed, Sheltered, Very sheltered, Extremely sheltered|
|Substratum||Bedrock; stable boulders and cobbles|
Download comparative physical and biological data. The comparative tables enable a rapid comparison of the species composition and principal physical characteristics between a given set of biotopes.
- Records used to define the biotope (core records)
- Other records assigned to this biotope, marked as 'certain'
- Other records assigned to this biotope, marked as 'uncertain'
Point data based on records in the UK Marine Recorder Snapshot.
Bedrock or stable boulders and cobbles in the littoral fringe which is covered by the black lichen Verrucaria maura. This lichen typically covers the entire rock surface giving a distinct black band in the upper littoral fringe. The winkle Littorina saxatilis is usually present. Two variants are defined which both occur in a wide range of wave exposures. On exposed shores V. maura may occur with sparse barnacles such as Chthamalus spp. or Semibalanus balanoides and may be covered by a band of ephemeral seaweeds such as Porphyra umbilicalis or Enteromorpha spp. (Ver.B). Above Ver.B or on more sheltered shores is a species poor community consisting mainly of V. maura and L. saxatilis (Ver.Ver).
This biotope occurs below the yellow and grey lichen zone (YG) and above eulittoral communities of barnacles and fuciod algae.
Discint band of red or green ephemeral algae may obscure the black lichen band at certain times of the year.
|Taxon||Relative importance of taxon for defining this community (%)||Typical abundance - SACFOR scale||% of core records where taxon was recorded|
|Littorina saxatilis||10||Frequent||41-60 %|
|Verrucaria maura||81||Abundant||81-100 %|
Not applicable or unknown.