Marine Biodiversity Data Portal - NI

Place name : Ruecallan Archway, Rathlin Island. County : Antrim

Date : 2025-05-18 GPS : 55.30788,-6.26920. Depth : -20.0 to -32.0 m. [ View map ]

Site Description : Vertical limestone wall with archway on Rathlin's north wall. There is a small cave with muddy bottom in the wall.

Yellow staghorn sponge, Axinella dissimilis, [00:00:31]; White and yellow soft corals, Alcyonium digitatum, [00:00:57]; Yellow hedgehog sponge, Polymastia boletiformis, [00:01:20]; Yellow cluster anemones, Parazoanthus axinellae, [00:01:29]; Orange sea squirt, Dendrodoa grossularia, [00:02:24]; Diver bubbles coming through the limestone, [00:03:22]; Devonshire cup corals, Caryophyllia smithii, [00:04:01]; Nudibranch, Duvaucelia lineata, [00:04:35]; White form of elephant hide sponge, Pachymatisma johnstonia, [00:04:50]; Slender sea pen, Virgularia mirabilis, [00:06:07]; Sea beech, Delesseria sanguinea, [00:06:48]; Forest kelp, Laminaria hyperborea, in process of casting off old growth, [00:07:18]; Yellow sponge, Spongosorites calcicola, [00:08:02]; Kelp forest, Laminaria hyperborea, [00:08:58]; Northern tooth weed, Odonthalia dentata, [00:10:23]; Guillemot, Uria aalge, [00:11:08]

Species list (74 species recorded):

PORIFERA
Sycon sp.
Dysidea fragilis
Pachymatisma johnstonia
Dercitus bucklandi
Axinella dissimilis
Axinella infundibuliformis
Raspailia hispida
Raspailia ramosa
Stelligera stuposa
Polymastia boletiformis
Polymastia penicillus
Sphaerotylus renoufi
Tethya citrina
Iophonopsis nigricans
Lissodendoryx jenjonesae
Hemimycale columella
Hymedesmia paupertas
Hymedesmia rathlinia
Myxilla fimbriata
Myxilla incrustans
Desmacella cf. annexa
Spongosorites calcicola
Haliclona urceolus
Haliclona viscosa
CNIDARIA
Tubularia indivisa
Halecium halecinum
Tamarisca tamarisca
Nemertesia antennina
Nemertesia ramosa
Aglaophenia tubulifera
Obelia geniculata
Alcyonium digitatum
Alcyonium hibernicum
Virgularia mirabilis
Synarachnactis lloydii
Parazoanthus anguicomus
Parazoanthus axinellae
Actinothoe sphyrodeta
Corynactis viridis
Caryophyllia inornata
Caryophyllia smithii
ANNELIDA
Filograna implexa
CRUSTACEA
Adna anglica
MOLLUSCA
Calliostoma zizyphinum
Hinia (Hima) incrassata
Polycera faeroensis
Edmundsella pedata
Amphorina farrani
Facelina auriculata
BRYOZOA
Crisia denticulata
Crisia eburnea
Bugulina flabellata
Caberea boryi
Cellaria sp.
ECHINODERMATA
Henricia oculata
TUNICATA
Clavelina lepadiformis
Aplidium nordmanni
Aplidium punctum
Didemnidae sp.
Ascidiella aspersa
Ascidia mentula
Polycarpa pomaria
Dendrodoa grossularia
PISCES
Thorogobius ephippiatus
RHODOPHYTA
Corallina officinalis
Dilsea carnosa
Heterosiphonia plumosa
Cryptopleura ramosa
Delesseria sanguinea
Drachiella heterocarpa
Phycodrys rubens
Odonthalia dentata
CHROMOPHYTA
Laminaria hyperborea
Saccorhiza polyschides

Biotope 1 : Sponges and anemones on vertical circalittoral bedrock.

Biotope 2 : Circalittoral fine mud

Biotope 3 : Laminaria hyperborea forest with dense foliose red seaweeds on exposed upper infralittoral rock.