| Name | Notes |
|---|---|
| gut weed | Ulva intestinalis (ulvaceae) |
| Key criteria: | Large (to 25 cm) usually unbranched tubular species that occupies a variety of habitats in the mid to upper intertidal zone mostly epilithic and penetrating into estuaries. Relatively easily identified when unbranched; branched forms can be confused with E. compressa. Widespread and almost ubiquitous intertidally in the area as shown here. epilithic upper intertidal intertidal |
| gut weed | Ulva intestinalis (ulvaceae) |
| Key criteria: | Large (to 25 cm) usually unbranched tubular species that occupies a variety of habitats in the mid to upper intertidal zone mostly epilithic and penetrating into estuaries. Relatively easily identified when unbranched; branched forms can be confused with E. compressa. Widespread and almost ubiquitous intertidally in the area as shown here. epilithic upper intertidal intertidal |
| sea lettuce | Ulva lactuca (ulvaceae) |
| Key criteria: | Large (to 50 cm) blade-like species of varying shapes that occupies a variety of habitats in the lower intertidal and shallow subtidal zones growing mostly epilithically particularly in pools.Members of this genus are extremely difficult to separate morphologically and the recorded locations probably represent several different entities. epilithic lower intertidal intertidal shallow subtidal subtidal pool |
| no common name | Blidingia marginata (ulvaceae) |
| Key criteria: | Small (usually < 5 cm) finely branched tubular species that grows on hard substrata in the upper intertidal zone on open coasts and penetrating into estuaries. Distinctive microscopically Blidingia species could otherwise be confused with species of Ulva. Widespread in the area as shown here. upper intertidal intertidal |
| no common name | Blidingia minima (ulvaceae) |
| Key criteria: | Small (usually < 5 cm) finely branched tubular species that grows on hard substrata in the upper intertidal zone on open coasts and penetrating into estuaries. Distinctive microscopically it could otherwise be confused with species of Ulva. Widespread and common in the area as shown here. upper intertidal intertidal |
| tape weed | Ulva compressa (ulvaceae) |
| Key criteria: | Large (to 25 cm) usually branched tubular species that occupies a variety of habitats in the lower intertidal zone growing both epilithically and epiphytically on larger algae but not penetrating far into estuaries. Relatively easily identified it is most likely to be confused with branched forms of E. intestinalis. Widespread and very common in the area as shown here. epiphyte epilithic lower intertidal intertidal |
| no common name | Ulva flexuosa (ulvaceae) |
| Key criteria: | Large (to 25 cm) branched tubular species that is most common in sheltered situations where it forms mats. Difficult to distinguish from the more common species U. prolifera. sheltered |
| double ribbon weed | Ulva linza (ulvaceae) |
| Key criteria: | Large (to 25 cm) ribbon-like species that occupies a variety of habitats in the lower intertidal zone growing both epilithically and epiphytically on larger algae particularly in pools. Relatively easily identified it is most likely to be confused with narrow forms of Ulva spp. Widespread and very common in the area as shown here. epiphyte epilithic lower intertidal intertidal pool |
| no common name | Ulva muscoides (ulvaceae) |
| Key criteria: | Large (to 20 cm) much-branched tubular species that occupies a variety of habitats in the mid and lower intertidal and shallow subtidal growing both epilithically and epiphytically on larger algae particularly in pools. Relatively easily identified when bearing toothed proliferations and otherwise by microscopic examination of the plastids. Widespread but relatively rare in the area as shown here. epiphyte epilithic lower intertidal intertidal shallow subtidal subtidal pool |
| no common name | Ulva prolifera (ulvaceae) |
| Key criteria: | Large (to 50 cm +) branching tubular species that occupies a variety of habitats in the intertidal and subtidal zones growing both epilithically and epiphytically on larger algae and penetrating high into estuaries. Relatively easily identified it is most likely to be confused with E. compressa or Blidingia spp. Widespread and very common in the area as shown here. epiphyte epilithic intertidal subtidal |
| no common name | Ulva ralfsii (ulvaceae) |
| Key criteria: | Large (to 15 cm) finely branched tubular species. Very poorly known in the area and requiring further taxonomic investigation. ~ |
| no common name | Ulva rigida (ulvaceae) |
| Key criteria: | Large (to 50+ cm) blade-like species of varying shapes that is most common in the shallow subtidal zone growing mostly epilithically. Members of this genus are extremely difficult to separate morphologically. epilithic shallow subtidal subtidal |
| no common name | Ulvella lens (ulvaceae) |
| Key criteria: | A discoid microscopic plant found both intertidally and subtidally on hard surfaces and as an epiphyte. Likely to be much more widespread in the area. The apparent concentration in Northern Ireland is an artifact due to an intensive survey by collectors familiar with this species. Likely to be under-recorded elsewhere owing to its obscure habit. epiphyte intertidal subtidal |
| no common name | Umbraulva olivascens (ulvaceae) |
| Key criteria: | A southern species which may be more widespread on southern and western coasts. Easily confused with Ulva lactuca which could result in lack of records. ~ |
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.