Skip to content

22. Horastrea indica


Horastrea indica is a massive colonial coral species that is only found in the Western Indian Ocean on tropical reef systems off the coasts of countries such as Mozambique, Tanzania, Madagascar.

A combination of threats including fish bombing, disease and the impacts of climate change has reduced this species’ habitat. Specific population trends are unkown but widespread declines can be presumed.

The reproductive method of this species is currently unclear. The most common method used by reef building corals is that of broadcast spawning, however the Siderastreidae family contains a diverse group of species that have not been thoroughly studied.

  • Order: Scleractinia
  • Family: Siderastreidae
  • Trend: unknown
  • Depth Range (m): 20

EDGE Score

EDGE Score: 4.22 (?)
ED Score: 16.04 (?)
GE / IUCN Red List (?)
Not Evaluated Data Deficient Least Concern Near Threatened Vulnerable Endangered Critically Endangered Extinct in the Wild Extinct


This species is only found in the southwest Indian Ocean and along the East African coast and Madagascar.

Habitat and Ecology

This species occurs in shallow, tropical reef environments, generally to depths of 20m, in sandy reef areas.

It is a colonial, stony coral species meaning that as the individual animals (polyps) of this species grow they exude calcium carbonate to form exoskeletons (corallites) for protection.

Find out more

This wordcloud illustrates the threats facing this species. The size of each word indicates the extent of a species range that is affected by that threat (larger size means a greater area is affected). The colour of the word indicates how much that threat impacts the species (darker shades of red mean the threat is more severe).

Urban development Industrial development Tourism Extreme temperatures Extreme weather Shipping Fishing Recreation Invasive species Native species Wastewater Industry Agriculture Air pollution

Threat wordcloud key:

Small area affected
Large area affected
Least severe
Most severe
Severity unknown
Source: The IUCN List of Threatened Species. Version 2017.1.
Available at:

Radonirina Botosoamananto

  • Project name: Preliminary assessment of the population status of Horastrea indica in southwest Madagascar
  • Project site: Andavadoaka, Madagascar
  • Active: 2012 - 2014
Find out more