During the routine biological investigations on Epinephelus

diacanthus (Spiny cheek grouper), a fish with a pair of cysts attached to the abdominal musculature was observed. The cysts were oval, thin-walled, dark grey coloured,

measured approximately 3 cm in diameter, and located adjacent to each other

Joshy, Aswathy

Nair, Rekha J

Peter, Reynold

Santhosh, B

Sharma, S R Krupesha

Sumithra, T G

CMFRI Digital Repository

ICAR-CMFRI | Marine Fisheries Information Service Technical & Extension Series No. 248, 2021 41Entangled biomass of Semiya Paasi and a close-up view of A.verticillataA case of encysted endoparasitic copepods in the Spiny cheek grouperDuring the routine biological investigations on Epinephelus diacanthus (Spiny cheek grouper), a fish with a pair of cysts attached to the abdominal musculature was observed. The cysts were oval, thin-walled, dark grey coloured, measured approximately 3 cm in diameter, and located adjacent to each other. The cysts were firmly attached to the abdominal musculature and contained black cystic fluid. Microscopic examination of the wet impressions of the cystic fluid revealed the presence of large numbers of nauplii of copepods. Histopathologically, the cystic wall consisted of fibro-collagenous and adipose tissue. The copepods were found attached to the walls of the cyst. Preliminary studies involving amplification of a 1000 bp region of internal transcribed spacer-2 of rRNA indicated the resemblance of observed copepods to Tigriopus sp. While the occurrence of copepod parasites in fish is common, reports on endoparasitic copepods are rare and this is the first report from Indian waters. The cysts usually will be visible only when fish are filleted. The encysted parasitic copepods may not be harmful to fish, but they may adversely affect consumer preference and lead to fillet rejections.(Reported by: S. R. Krupesha Sharma*, Rekha J. Nair, T. G. Sumithra, Aswathy Joshy, Reynold Peter and B. Santhosh | ICAR-Central Marine Fisheries Research Institute, Kochi-682 018)Semiya Paasi is not seaweed but a bryozoanBryozoans found in  mar ine environments are commonly called sea mats, moss animals or lace corals and are found from the intertidal zone to some of the deepest parts of the ocean. There are about 6,500 recognized living species worldwide and about 257 species have been documented from India forming 4 percent of the total global bryozoans’ diversity. Thirty species of bryozoans belonging to 19 families have been documented from the Gulf of Mannar. They reproduce by budding new parts asexually and these new additions which contain functioning individuals called ‘zooid’ are attached to the parent but capable of feeding independently.During the regular survey in July 2020 along the Palk Bay coast on shore seine landings at Dhargavalasai in Ramanathapuram district of Tamil Nadu, a seaweed like entangled mass was collected from the fishing nets. Local fishermen called it ‘Semiya Paasi’ means a vermicelli like seaweed. The sample were brought to the laboratory and identified as bryozoan Amathia verticillata (della Chiaje, 1822). Formerly known as Zoobotryon verticillatum, it is typical of many ctenosome bryozoa on account of colony size and colour. It has irregular tripartite branching and a propensity to tangle once removed from the water. A. verticillata attaches to a wide range of substrata apart from natural surfaces including quay walls and boat hulls. In the present case, A. verticillata was discarded by fishermen in heaps from the shoreseine operations and its invasive nature needs further study in this region. Globally, some potentially exciting pharmaceutical applications of bryozoans have been reported, in particular the bioactive compounds such as bryostatin-1 and janolusimide B which have a range of anti-cancer, anti-fouling and anti-fungal properties.(Reported by R. Saravanan*, I. Syed Sadiq and K. K. Joshi | Mandapam Regional Centre of ICAR-CMFRI )

A case of encysted endoparasitic copepods in the Spiny cheek grouper

http://eprints.cmfri.org.in/15227/1/MFIS_248_S%20R%20Krupesha%20Sharma_2021.pdf

A case of encysted endoparasitic copepods in the Spiny cheek grouper

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