Halodule emarginata 


Taxonomy [top]

Kingdom Phylum Class Order Family
Plantae Tracheophyta Liliopsida Najadales Cymodoceaceae

Scientific Name: Halodule emarginata
Species Authority: Hartog
Common Name(s):
English Species code: Hg
Taxonomic Notes: The taxonomy of this species is questionable and it may eventually be found as conspecific with Halodule wrightii. Its taxonomic status is based on leaf-tip morphology which is highly variable (Larkum et al. 2006).

Assessment Information [top]

Red List Category & Criteria: Data Deficient ver 3.1
Year Published: 2010
Date Assessed: 2007-03-21
Assessor(s): Short, F.T., Carruthers, T.J.R., van Tussenbroek, B. & Zieman, J.
Reviewer(s): Livingstone, S., Harwell, H. & Carpenter, K.E.
Halodule emarginata is endemic to Brazil. Its current taxonomic status is based on leaf-tip morphology which is highly variable. This species is listed as Data Deficient. More research is needed on this species taxonomy, population status, and potential threats, especially as it has disappeared from a known site near Rio de Janeiro.

Geographic Range [top]

Range Description: Halodule emarginata is endemic to Brazil where it ranges from Rio de Janiero to Baía de Todos os Santos.
Countries occurrence:
FAO Marine Fishing Areas:
Atlantic – southwest
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population: There is little population information available for Halodule emarginata. One of the known sites for this species has disappeared from Rio de Janiero (F. Short pers. comm. 2008).
Current Population Trend: Unknown
Additional data:
Population severely fragmented: No

Habitat and Ecology [top]

Habitat and Ecology: Halodule emarginata is found in sheltered shores, in fine-sediment substrate and salinities around 35 ppt (de Oliveira et al. 1983). It is a perennial species that produces flowers (Zieman 1982, UNESCO 1998, Hemminga and Duarte 2000, Green and Short 2003, Larkum et al. 2006).
Systems: Marine

Threats [top]

Major Threat(s): Specific threats to Halodule emarginata are unknown. Localized coastal development is most likely a threat.

Conservation Actions [top]

Conservation Actions: Conservation measures for Halodule emarginata are unknown. More research is needed on this species taxonomy, population status, and potential threats.

Classifications [top]

9. Marine Neritic -> 9.4. Marine Neritic - Subtidal Sandy
suitability: Suitable  
9. Marine Neritic -> 9.9. Marine Neritic - Seagrass (Submerged)
suitability: Suitable  
12. Marine Intertidal -> 12.2. Marine Intertidal - Sandy Shoreline and/or Beaches, Sand Bars, Spits, Etc
suitability: Suitable  

In-Place Research, Monitoring and Planning
In-Place Land/Water Protection and Management
In-Place Species Management
In-Place Education
1. Residential & commercial development -> 1.1. Housing & urban areas
♦ timing: Ongoing    
→ Stresses
  • 1. Ecosystem stresses -> 1.2. Ecosystem degradation
  • 2. Species Stresses -> 2.2. Species disturbance

1. Research -> 1.1. Taxonomy
1. Research -> 1.2. Population size, distribution & trends
1. Research -> 1.5. Threats

Bibliography [top]

de Oliveira, F.E.C., Pirani, J.R. and Giulietti, A.M. 1983. The Brazilian seagrasses. Aquatic Biology 16(3): 251-267.

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

Hemminga, M.A. and Duarte, C.M. 2000. Seagrass Ecology. Cambridge University Press, Cambridge.

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

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

Short, F.T., Fernandez, E., Vernon, A. and Gaeckle, J.L. 2006. Occurrence of Halophila baillonii meadows in Belize, Central America. Aquatic Botany 85: 249-251.

UNESCO. 1998. CARICOMP-Caribbean coral reef, seagrass and mangrove sites. Coastal region and small island papers. UNESCO, Paris.

Zieman, J.C. 1982. The ecology of the seagrasses of South Florida: a community profile. US Fish and Wildlife Service Biological Services Program FWS/OBS-82/5: 150.

Citation: Short, F.T., Carruthers, T.J.R., van Tussenbroek, B. & Zieman, J. 2010. Halodule emarginata. The IUCN Red List of Threatened Species 2010: e.T173347A6996342. . Downloaded on 26 November 2015.
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