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The survey along the Tamilnadu and Kerala coats of India reveled that six species of seahors (Hippocampus fuscus, H. kelloggi, H. kuda, H. histrix, H. mohnikei and H. trimaculatus) were distributed with different density. Out of the six species, H. fuscus, H. kuda and H. trimaculatus, were the commonly available in all the observed areas. In Palk Bay, H. kuda was the dominant species constituting 49.10% of the total seahorses encountered. Hippocampus trimaculatus was the second dominant species which accounting 39.28%. The Gulf of Mannar region also most abounded with H. kuda (68.98%) followed by H. trimaculatus (20.80%), H. fuscus (9.80%), H. kelloggi (2.23%) and H. histrix (0.37%). In Kerala coast, H. trimaculatus was the dominant species (79.68%) followed by H. kuda (9.89%), H. kelloggi (8.33%) and H. fuscus (2.08%). To infer the variation of six seahorse species, the morphometric and meristic characters were analysed. The important morphometric and meristic characters are trunk rings, tail rings, pectoral and dorsal fin rays, trunk length, tail length, coronet height, head length, snout length, snout depth and head depth. Variations in overall body shape, relative snout length, coronet height, number of tail ring was sufficient to separate the specimens to Hippocampus fuscus, H. kelloggi, H. kuda, H. histrix, H. mohnikei and H. trimaculatus. The species density and diversity depends on the habitat and biogeography of those areas. Majority of seahorse fishing in Tamilnadu was by shrimp trawl, by-catch and very few target catch by divers also seen in some villages in Palk Bay and Gulf of Mannar region. The shrimp trawl by-catch only bringing more H. trimaculatus than the other seahorse species in Kerala coasts. [ABSTRACT FROM AUTHOR]

Patterns of copepod - appendicularian distribution were studied along the Mangalore coastal waters (12°50'49° N; 74°48'50" E) of the Arabian Sea to understand the food and feeding relationship existing among these groups. Sampling was conducted during pre-monsoon, monsoon and post-monsoon extending from January 2009 to December 2010. The copepod and appendicularian community was sampled with a 60 μm net to include the smallest species and their developmental stages. Copepod biomass, especially calanoids, was substantially high throughout the study. Seasonal mean results showed that the small-sized copepods (calanoids, harpacticoida and cyclopoids) dominated in terms of biomass and production. Calanoids found in abundance included Acartia, Centropages, Calanus, Eucalanus and Labidocera. Cyclopoid and Harpacticoid copepods genera dominated included Oithona, Oncaea and Microsetella, Macrosetella. Appendicularian species diversity was represented by Oikopleura fusiformis, O. dioica and its juveniles represented as Oikopleura sp. Total chlorophyll (chlorophyll a) ranging between 10 and 20 mg m-3 indicated the eutrophic state as well as productivity prevailing during the study period. Principal component analysis (PCA) indicated the routine and opportunistic seasonal grazers and establishes a phytoplankton - appendicularia - copepod - fish food chain relationship along Mangalore coast. [ABSTRACT FROM AUTHOR]

Morphology of the marine egg bearing cyclopoid copepod Oithona similis occurring along the southwest coast of India [Vizhinjam (8°21'56"N; 76°59'39"E), Neendakara (8°57'29"N; 76°31'13"E), Cochin (9°56'16"N; 76°13'55"E) and Calicut (11°13'33"N; 75°46'30"E)] from January to December 2010 at different seasons (pre monsoon, monsoon and post monsoon) were studied. Detailed comparison of the structure of different appendages of O. similis with those already available for the species from Norway, Japan, China, Spain and Russia revealed minute differences in the armature of appendages, number and arrangement of spines, setae of swimming legs and anal laminae. The total length of the specimen collected from all the four stations in the study ranged from 615 to 650μ. The smallest specimens were obtained from Calicut. [ABSTRACT FROM AUTHOR]

The marine red alga Laurencia brandenii collected from the southwest coast of India (Indian Ocean) was extracted and fractioned using column chromatography. The individual fractions were evaluated in vitro via antimicrobial activity against six species of Microbial Type Culture Collection and three species of clinical human pathogens, antipest activity on Sitophilus oryzae, maggoticidal activity against 2nd instar larvae of Sarcophaga sp. and termiticidal activity against Microtermes obesi. It was found that the fraction eluted using petroleum ether:chloroform (6:4) exhibited broader biological activities. The phyco-constituents of the active fraction were identified by gas chromatography-mass spectrometry (GC-MS) analysis. The GC-MS profile of the active fraction revealed that the main constituent was octadecadienoic acid (49.75%) followed by n-hexadecanoic acid (14.24%), which might have a functional role in the biological activities. The overall activity profile envisages that these bioactive compounds from L. brandenii could be utilized as a renewable natural resource for the development of novel environmental-compatible formulations for the control of human pathogens, pests, termites and maggots. [ABSTRACT FROM AUTHOR]