Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Chordata Actinopterygii Perciformes Chaenopsidae

Scientific Name: Acanthemblemaria atrata
Species Authority: Hastings & Robertson, 1999
Common Name(s):
English Cocos Barnacle Blenny
Taxonomic Source(s): Eschmeyer, W.N. (ed.). 2014. Catalog of Fishes. Updated 27 August 2014. Available at: (Accessed: 27 August 2014).

Assessment Information [top]

Red List Category & Criteria: Vulnerable D2 ver 3.1
Year Published: 2010
Date Assessed: 2007-05-25
Assessor(s): Bessudo, S., Dominici-Arosemena, A., Espinosa, H. & Hastings, P.
Reviewer(s): Carpenter, K., Polidoro, B. & Livingstone, S. (Global Marine Species Assessment Team)
This species is only known from one location (Cocos Island). Regional experts support the plausible threat of the increased duration and frequency of ENSO events that can cause severe and rapid declines for restricted-range, shallow-water species in this region of the Eastern Tropical Pacific. This species is listed as Vulnerable under Criterion D2.

Geographic Range [top]

Range Description: This species is endemic to the Eastern Pacific, and is only found near Cocos Island, Costa Rica.
Countries occurrence:
Costa Rica
FAO Marine Fishing Areas:
Pacific – eastern central
Number of Locations: 1
Lower depth limit (metres): 30
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population: This species is common, although easily overlooked by divers.
Current Population Trend: Unknown
Additional data:
Population severely fragmented: No

Habitat and Ecology [top]

Habitat and Ecology: This demersal, reef-associated species is found in barnacles and worm tubes on rocky shores and in rocky and coral reef to depths of 30 m. It is oviparous, and its eggs are attached to the walls of the parent's shelter and are brooded by the male parent (Matarese et al. 1984).
Systems: Marine

Threats [top]

Major Threat(s): In the Eastern Tropical Pacific, severe localized fish species declines have occurred after strong ENSO events that result in shallow waters that are too warm and nutrient poor for extended periods of time (Grove 1985, Edgar et al. 2009). The frequency and duration of ENSO events in this region of the Eastern Tropical Pacific (e.g. the up-welling zone off the coast of Peru, Ecuador, Colombia, Panama and the offshore islands) appears to be increasing (Glynn and Ault 2000, Soto 2001, Chen et al. 2004). Given this species' restricted distribution and shallow water habitat, oceanographic environmental changes, such as those associated with future ENSO events, may have detrimental effects on the survival of this species.

Conservation Actions [top]

Conservation Actions: Cocos Island is protected as a National Park, and is a UNESCO World Heritage Site (WDPA 2006). However, this species requires close population monitoring given its very restricted range.

Citation: Bessudo, S., Dominici-Arosemena, A., Espinosa, H. & Hastings, P. 2010. Acanthemblemaria atrata. The IUCN Red List of Threatened Species 2010: e.T183583A8139402. . Downloaded on 04 October 2015.
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