No abstract

Sporadic and seasonal landings of jellyfishes along the southern coast of India have been under investigation since 2018. The catostylid jellyfish Crambionella orsini is the only species that contributes to a fishery in this region. In the October to January months, a seasonal fishery exists along the Kanyakumari, Thiruvananthapuram and Neendakara coast, with catches being made variously by gillnetters, single day trawlers, multi-day trawlers and shore seines. An unprecedented 44 day fishery on the Neendakara coast from December 2020 to January 2021 was investigated in depth, with estimated landings of 453.16 metric tonnes landed at Sakthikulangara and Neendakara Fisheries Harbours in Kollam District, Kerala. Economic efficiency of the fishery from Sakthikulangara Fisheries Harbour was estimated as 44.76 gross value added as percentage of gross revenue and net operating income of `1313 per fishing trip with average earning to a crew member being `510 per trip. The oral arms of C. orsini is the only part of the jellyfish that are traded and exported, mainly to China and South east Asian countries after salt curing. Emergence of this augmentative fishery has come as a boon to fishers combating the regressive environment of the Covid-19 period. Promotion of this fishery with increased processing and export facilities and investigations into value added products from the resource is recommended.

This work reports the first distributional record of Filinia camasecla Myers, 1938 in south India from the Cochin backwaters on the northern stretch of Lake Vembanad. Earlier, the distribution of this species has been known from Oriental (South East-Asia) and Neotropical biogeographical realms. Though it comes under the oriental endemics no previous records of this species were available from this area or other parts of Vembanad backwaters. The occurrence of F. camasecla in this additional geographic region highlights the range extension of the species.

A predatory relationship between the nudibranch belonging to the Family Aeolidiidae, Aeolidiopsis sp. and a zoanthid-Palythoa mutuki was recorded from coastal waters of Veraval, Gujarat, India. This is the first record of nudibranch predation on Zoantharians along Indian waters. The Aeolidiopsis sp. of nudibranch was found alive, attached and feeding on the colonies of P. mutuki in coastal waters. Observations in controlled environment also revealed metabolic dependence of the nudibranch on the host. The nudibranch was seen completing its life cycle in the host, as its eggs were observed, laid in concentric ring pattern and the presence of the juveniles. These observations and the existing knowledge of them harbouring zooxanthellae make the Aeolidiopsis sp. to be categorised as a facultative ectoparasite instead of a predator.