CRAB
SPECIES - ENVIRONMENT
News: New species of estuarine crab discovered in Cuddalore named after Annamalai University
What's
in the news?
●
Researchers have discovered a new species
of estuarine crab at the mangroves of Parangipettai near the Vellar River estuary in Cuddalore district.
● The species has been named Pseudohelice annamalai in recognition of Annamalai University’s 100 years of service in education and research.
Key
takeaways:
Discovery:
●
Specimens of Pseudohelice annamalai were
collected from the high intertidal areas
of the Vellar River estuary, Parangipettai, with sediments composed of mud and
sand.
● The mangroves in the habitats were artificially planted on five hectares along the northern bank of the river, with two distinct zones - Rhizophora spp. towards the estuary and Avicennia spp. towards the land in the intertidal area.
Features
of Pseudohelice annamalai:
●
Pseudohelice annamalai is distinguished by
dark purple to dark grey colouring,
with irregular light brown, yellowish brown, or white patches on the posterior
carapace with light brown chelipeds.
●
The new
species is small and has a maximum width of up to 20 mm.
●
Habitat:
The species inhabits muddy banks of mangroves, and the burrows were located
near the pneumatophores of Avicennia
mangroves.
●
Burrows have a depth of 25-30 cm and are
branched, with larger pellets around the entrance.
●
This species is not aggressive and can move fast like other intertidal crabs. As
many as 17 species of intertidal crabs have been recorded in the same region.
●
The occurrence of Pseudohelice in India links the distribution gap between the
western Indian Ocean and the western Pacific Ocean.
●
The new species provides additional evidence of the geographic
isolation of the eastern Indian Ocean for some marine organisms.