Ruppia megacarpa 


Taxonomy [top]

Kingdom Phylum Class Order Family
Plantae Tracheophyta Liliopsida Najadales Potamogetonaceae

Scientific Name: Ruppia megacarpa
Species Authority: R.Mason
Common Name(s):
English Large-fruit seatassel
Taxonomic Notes: The taxonomy of the Ruppia genus is confused. These species can be extremely morphologically variable and respond differently to differing environmental conditions. Therefore, species identifications often link to differences in environmental conditions. This species is potentially a synonym of Ruppia maritima. Flower morphology and genetic studies are needed to evaluate the distribution limits of this species (Larkum et al. 2006).

Assessment Information [top]

Red List Category & Criteria: Least Concern ver 3.1
Year Published: 2010
Date Assessed: 2007-10-23
Assessor(s): Short, F.T., Carruthers, T.J.R., Waycott, M., Kendrick, G.A., Fourqurean, J.W., Callabine, A., Kenworthy, W.J. & Dennison, W.C.
Reviewer(s): Livingstone, S., Harwell, H. & Carpenter, K.E.
Ruppia megacarpa is found in south western Australia and south eastern Australia. It also has been recorded from South Island in New Zealand. There are no major threats other than localized threats from coastal development and other anthropogenic activities. The overall population is thought to be stable. This species is listed as Least Concern.

Geographic Range [top]

Range Description:Ruppia megacarpa occurs in south Western Australia, eastern South Australia, and western Victoria, Australia. It also is recorded along the central coast of New South Wales, Australia and in New Zealand.
Countries occurrence:
Australia; New Zealand
FAO Marine Fishing Areas:
Indian Ocean – eastern; Pacific – southwest
Range Map:Click here to open the map viewer and explore range.

Population [top]

Population:There is no population information on this species. The overall population is thought to be stable.
Current Population Trend:Stable
Additional data:
Population severely fragmented:No

Habitat and Ecology [top]

Habitat and Ecology:Ruppia megacarpa is a rhizomatous perennial species that occurs widely in Australia and New Zealand, found growing in permanent water bodies such as estuaries, coastal salt lakes and inland brackish to hypersaline lakes (Jacobs and Brock 1982, Womersley 1984).

Ruppia megacarpa is slow to develop and shows late maturity. The small amount of energy allocated to producing a small number of large propagules appears suitable for interpretation as an example of K-selection (Brock 1983).
Systems:Freshwater; Marine
Generation Length (years):1

Threats [top]

Major Threat(s): Localized reduction of this species can be caused by increased sediment loads in water. Coastal development, dredging and marine developments may also locally impact this species.

Conservation Actions [top]

Conservation Actions: This species is protected in various Marine Protected Areas (MPAs), in Fisheries Acts and National and Marine Park Acts (Green and Short 2003).

Classifications [top]

9. Marine Neritic -> 9.4. Marine Neritic - Subtidal Sandy
suitability: Suitable  
9. Marine Neritic -> 9.9. Marine Neritic - Seagrass (Submerged)
suitability: Suitable  
9. Marine Neritic -> 9.10. Marine Neritic - Estuaries
suitability: Suitable  
13. Marine Coastal/Supratidal -> 13.4. Marine Coastal/Supratidal - Coastal Brackish/Saline Lagoons/Marine Lakes
suitability: Suitable  

In-Place Research, Monitoring and Planning
In-Place Land/Water Protection and Management
  Conservation sites identified:Yes, over entire range
  Occur in at least one PA:Yes
In-Place Species Management
In-Place Education
1. Residential & commercial development -> 1.2. Commercial & industrial areas
♦ timing: Ongoing    
→ Stresses
  • 1. Ecosystem stresses -> 1.2. Ecosystem degradation
  • 2. Species Stresses -> 2.2. Species disturbance

9. Pollution -> 9.3. Agricultural & forestry effluents -> 9.3.2. Soil erosion, sedimentation
♦ timing: Ongoing    
→ Stresses
  • 1. Ecosystem stresses -> 1.2. Ecosystem degradation
  • 2. Species Stresses -> 2.2. Species disturbance

1. Research -> 1.1. Taxonomy

Bibliography [top]

Brock, M.A. 1983. Reproductive allocation in annual and perennial species of the submerged aquatic halophyte Ruppia. The Journal of Ecology 71(3): 811-818.

Green, E.P. and Short, F.T. 2003. World Atlas of Seagrasses. University of California Press, Berkeley.

IUCN. 2010. IUCN Red List of Threatened Species (ver. 2010.3). Available at: (Accessed: 2 September 2010).

Jacobs, S.W.L. and Brock, M.A. 1982. A revision of the genus Ruppia (Potamogetonaceae) in Australia. Aquatic Botany Amsterdam 14: 325-337.

Larkum, A.W.D., Orth, R.J. and Duarte, C.M. (eds). 2006. Seagrasses: Biology, Ecology and Conservation. Springer, Dordrecht.

Womersley, H.B.S. 1984. The Marine Benthic Flora of Southern Australia. Part I. Handbook of the Flora & Fauna of South Australia. South Australian Government Printing Division, Netley, South Australia.

Citation: Short, F.T., Carruthers, T.J.R., Waycott, M., Kendrick, G.A., Fourqurean, J.W., Callabine, A., Kenworthy, W.J. & Dennison, W.C. 2010. Ruppia megacarpa. In: The IUCN Red List of Threatened Species 2010: e.T173351A6997332. . Downloaded on 01 December 2015.
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