Ceylonthelphusa callista


Taxonomy [top]

Kingdom Phylum Class Order Family

Scientific Name: Ceylonthelphusa callista
Species Authority: (Ng, 1995)
Taxonomic Notes: This species was formerly included in the Parathelphusidae but has recently been reassigned to the Gecarcinucidae; Parathelphusidae is now regarded as a junior synonym of Gecarcinucidae (Klause et al. in press).

Assessment Information [top]

Red List Category & Criteria: Critically Endangered B1ab(iii)+2ab(iii) ver 3.1
Year Published: 2008
Date Assessed: 2008-01-01
Assessor(s): Bahir, M.M., Ng, P.K.L., Crandall, K. & Pethiyagoda, R. and Cumberlidge, N.
Reviewer(s): Darwall, W. (IUCN Freshwater Biodiversity Assessment Unit), Pollock, C.M. (IUCN Red List Unit) and McIvor, A.
The assessment of Bahir et al. (2005) is followed here. Listed as Critically Endangered because this is a very rare species with an extent of occurrence of less than 100 km² and area of occupancy less than 10 km², with all individuals in a single locality in small populations, and there is continuing decline in the extent and quality of its habitat. Currently the range of this species is not protected and its habitat is subject to degradation because of direct human impacts.
2006 Critically Endangered

Geographic Range [top]

Range Description: Endemic to Sri Lanka. Mousakanda, near Gammuduwa, Knuckles Range, Mahaweili Range. Extent of occurrence and area of occupancy both <10 km². Known from only one location.
Sri Lanka
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population: This species is very rare.
Population Trend: Unknown

Habitat and Ecology [top]

Habitat and Ecology: This species was collected and observed on wet boulders on the margins of a slow-flowing stream. Occurs in freshwater aquatic habitats in the wet zone area of Sri Lanka.
Systems: Terrestrial; Freshwater

Threats [top]

Major Threat(s): Site not protected, area subject to degradation because of direct human impacts

Conservation Actions [top]

Conservation Actions: None in place. Not found in a protected area.

Citation: Bahir, M.M., Ng, P.K.L., Crandall, K. & Pethiyagoda, R. and Cumberlidge, N. 2008. Ceylonthelphusa callista. The IUCN Red List of Threatened Species. Version 2015.2. <>. Downloaded on 01 September 2015.
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