PORT PHILLIP BAY


Sea Lettuce 

Ulva rigida

View scientific description and taxonomy

Scientific Details

Similar to other species in the genus Ulva and most reliably distinguished by microscopic examination of cells.

Ulva australis: several sheet-like blades, blade edges without minute teeth, 2 sheets of cells that are longer than broad.

Ulva compressa: single sheet-like blade or cylindrical, ribbon-like branched form, cells in short lines or unordered.

Ulva lactuca: single sheet-like blade, edges without minute teeth, 2 layers of box-shaped cells.

Ulva linza: single paddle-like blade, cells square to rectangular in lines or arcs.

Ulva rigida: single sheet-like blade, edges with minute teeth, 2 layers of elongated, tapered cells.

Ulva taeniata: several narrow blades, edges with minute teeth, 2 layers of elongated, rounded cells.

Main information sources:
Womersley, H.B.S., (1984-2003). The Marine Benthic Flora of Southern Australia. Part 1-3d. Govt. Printer, South Australia.
Baldock, R.N. 2010. Algae Revealed. South Australian State Herbarium. Website.
AlgaeBase. Website.

Taxonomy

Phylum:
Chlorophyta
Subphylum:
Tetraphytina
Class:
Ulvophyceae
Order:
Ulvales
Family:
Ulvaceae
Genus:
Ulva
Species:
rigida

General Description

Broad and smooth flattened surface (sheet-like) as a single frond arising from holdfast either flat, divided and/or with tears and holes. Has minute (microscopic) teeth on the blade edges (margins). Holdfast at base is a mass of root-like (rhizoidal) extensions in lower cells. Grass green. Up to 30 cm long (thallus).

Biology

This sea lettuce sometimes grows as an epiphyte on seagrasses, invertebrates and other algae. Blooms can be common both seasonally and in areas of high nutrients e.g. near stormwater, stream run-off, sewerage outfalls.

Habitat

Tidal pools and subtidal rocky reefs, in sheltered and moderate wave action areas.

Reefs

Coastal shores

Seagrass meadows

Distribution guide

Wordlwide.

Species Group

Seaweeds and seagrasses Green algae

Depth

Shore (0-1 m)
Shallow (1-30 m)

Water Column

On or near sea floor

Max Size

30 cm

Diet

Photosynthetic - sunlight

Commercial Species

No

Global Dispersal

Recorded in Australia

Identify

Conservation Status

  • DSE Advisory List : Not listed
  • EPBC Act 1999 : Not listed
  • IUCN Red List : Not listed

Author

article author Pocklington, Jacqui

Jacqui Pocklington is a Research Associate with expertise in algal taxonomy.

citation

Cite this page as:
Pocklington, Jacqui, 2011, Sea Lettuce, Ulva rigida, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 23 Nov 2017, http://portphillipmarinelife.net.au:8098/species/12324

Text: creative commons cc by licence