| Name | Notes |
|---|---|
| spindle weed | Atractophora hypnoides (naccariaceae) |
| Key criteria: | Medium-sized gametophytes erect and gelatinous and epiphytic on coralline algae. Sporophytes unknown. Predominantly western distribution in shallow subtidal to 20 m. Rare. epiphyte shallow subtidal subtidal |
| Dudresnay's whorled weed | Dudresnaya verticillata (dumontiaceae) |
| Key criteria: | Small lubricous cylindrical fragile fronds with irregular branching. Epilithic on pebbles maerl and small stones in subtidal to about 13 m. often strong subtidal currents. Uncommon widely distributed but with a generally western distribution. epilithic subtidal |
| sticky tube weed | Gloiosiphonia capillaris (gloiosiphoniaceae) |
| Key criteria: | Gametophytes medium with cylindrical mucilaginous fronds with many proliferous branches above. Epilithic in shallow pools in the lower intertidal and subtidal to 5 m. Widely distributed but extraordinarily sporadic in spring or early summer. Rare. Tetrasporophytes crustose perhaps unknown in the area but see Plagiospora gracilis. epilithic lower intertidal intertidal subtidal pool |
| branched worm weed | Helminthocladia calvadosii (liagoraceae) |
| Key criteria: | Fairly large mucilaginous irregularly branched species found on rock in the very lower intertidal and shallow subtidal in summer. Rare and generally confined to south-western shores. Records from Shetland require confirmation. lower intertidal intertidal shallow subtidal subtidal rock |
| spreading worm weed | Helminthora divaricata (liagoraceae) |
| Key criteria: | Gametophytes are fairly large mucilaginous much-branched epiphyte of Polyides rotundus. The gametophytes are found from June-September in shallow lower-intertidal sunny pools. Uncommon and generally confined to south-western shores. Records from Scotland and eastern England require confirmation. Sporophytes occur as endophytes in Polyides rotundus. epiphyte endophyte intertidal pool |
| Naccari's hairy weed | Naccaria wiggii (naccariaceae) |
| Key criteria: | Large lubricous gametophytes. Sporophytes unknown in the wild. Predominantly south- western distribution in subtidal where it grows as an epiphyte. Present-day distribution is at odds with its type locality at Yarmouth (Norfolk in south-eastern England). Outlier station in northern Scotland requires confirmation. epiphyte subtidal |
| sea noodle | Nemalion helminthoides (liagoraceae) |
| Key criteria: | Gametophytes are fairly large sparingly but regularly branched gelatinous and found on rock limpets and barnacles on medium to strongly wave-exposed shores. Common and widespread except in south-eastern England. Sporophytes filamentous tufts but generally unknown in wild. Epilithic and epizoic. epilithic epizoic rock exposed |
| lobed jelly weed | Schmitzia hiscockiana (calosiphoniaceae) |
| Key criteria: | Gametophytes are small gelatinous ephemeral plants with strongly compressed little branched fronds. Known only from the subtidal to a depth of 15 m. where plants occur on cobbles in strong current flows in summer. Tetrasporophyte unknown in wild. Western distribution. Rare. subtidal depth |
| stringy jelly weed | Schmitziella endophloea (?acrochaetiaceae) |
| Key criteria: | Microscopic endophyte in the large basal cell of older plants of Cladophora pellucida. Common wherever the basiphyte occurs. Generally with western aspect to its distribution. endophyte |
A Check-list and Atlas of the Seaweeds of Britain and Ireland. F. G. Hardy and M. D. Guiry. The British Phycological Society, 2003. ISBN 0 9527115 16 Seaweeds of Britain and Ireland. Bunker, Brodie, Maggs and Bunker. Seasearch 2012.