Crab in Silent Valley found displayingboth male and female biological traits

 Aathira Haridas KOCHI, The Hindu

A tiny crab displaying both male and female biological traits on the same body has been discovered in the Western Ghats. Discovered from the forests of the Silent Valley National Park, this freshwater crab belongs to the species Vela carli and is both male and female at the same time. The dual-sex condition was observed in three crabs found in tree holes in Silent Valley.

Vela carli is an endemic freshwater crab found only in the forests and streams of the Central Western Ghats.

The study documents the first instance of gynandromorphy (a rare condition in which individuals exhibit both male and female characteristics) in Vela carli. This phenomenon is rare in crustaceans and has never before been reported in the freshwater crab family Gecarcinucidae, according to the researchers.

The study was carried out by K.S. Anoop Das and K.T. Fahis from the Centre for Conservation Ecology, MES Mampad College, in collaboration with scientist and crab specialist Sameer K. Pati and Purnima Kumari from the Zoological Survey of India.

Their findings were recently published in the international journal Crustaceana.

Mr. Das, Head and Assistant Professor at the Centre, said that while gynandromorphy has been documented in several marine and freshwater crab families, it has not been reported in the family Gecarcinucidae.

“The bodies of the crabs displayed male reproductive structures, while other parts showcased female features, including gonopores,” said Mr. Das.

According to him, the likely cause for this gynandromorphism could only be from intrinsic developmental processes rather than external environmental pollution.

“The crab’s habitat was free from environmental pollutants. So we think that the reason for the phenomenon could be related to survival tactics. This makes it possible for the crab to procreate in the absence of male or female members,” said Mr. Das.

The specimens were collected during biodiversity surveys conducted in the forest. Among the more than 120 crabs examined, only three crabs showed this dual-sex condition.

The study was funded by the Department of Science and Technology, Science and Engineering Research Board (presently Anusandhan National Research Foundation).

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New earthworm species at Vazhani addsto Western Ghats’ rich biodiversity

 

Sam Paul A. 

Kozhikode, the hindu

A team of researchers has identified a new earthworm species from the Vazhani dam area of the Peechi-Vazhani Wildlife Sanctuary in Thrissur.

Belonging to the genus Drawida, which is naturally restricted to the south, southeast and east asian region, and the family Moniligastridae, the earthworm has been named Drawida vazhania. The discovery has been published in the peer-reviewed journal Zootaxa.

According to the researchers involved in the discovery, Rajendran Menon Ardra of the Centre for Animal Taxonomy and Ecology under the Department of Zoology, Christ College, Irinjalakuda, and S. Prasanth Narayanan of Advanced Centre of Environmental Studies and Sustainable Development, Mahatma Gandhi University, Kottayam, D. vazhania, with small body size, is a member of the Barwelli species group.

With the description of the new species, the group now comprises seven species. D. vazhania can be easily differentiated from other members of the Barwelli group by the presence of a grooved male genital field, a kidney or bean-shaped prostate, a narrow tubular C-shaped prostatic capsule and a distinct small sessile atrium on the body wall.

India is one of the most earthworm diverse countries in the world, with about 71% of genera and 89% of species endemic to the country. The highest diversity of earthworms in India is found in the Western Ghats and the west coast plains, which together account for roughly 58.4% of all known earthworm species in the country. With the new finding, the total number of Drawida species reported from India and the Western Ghats biodiversity hotspot has risen to 83 and 55 respectively, the researchers said. Among the Western Ghats States, Kerala has the highest number of Drawida species, with 31 recorded so far, including 16 endemic to the State.

Mr. Narayanan said the main issues directly affecting earthworms in the Western Ghats are habitat destruction and transformation. “Kerala’s midlands and coastal lowlands have almost entirely lost their forest cover due to several human activities that have existed since time immemorial. There is practically no remaining protected land in the State’s midlands, except for a few areas of forest cover in the districts of Thrissur, Kollam, and Pathanamthitta,” he said. Other members of the research team include P. Sunil Kumar, A.V. Sudhikumar and A.P. Thomas.

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