There are currently 163 species of Geodia Lamarck, 1815 described worldwide, many of which are found in deep waters, but none of which have been recorded from the Southwest Indian Ridge (SWIR). Spicule morphology and barcodes (Folmer COI, 28S (C2D2), partial 18S) suggest that a specimen of Geodia collected on the SWIR at a depth of 2236 m is closely comparable to Geodia barretti Bowerbank, 1858. Geodia barretti is the most studied and thus well-known deep-sea Geodia species, due to its wide North Atlantic distribution and key role in boreal sponge grounds.
View Article and Find Full Text PDFUnderwater sampling via SCUBA and grab at the Angria Bank coral reefs off the central west coast of India in January 2014 revealed 11 species of Brachyura. Seven species, namely, Thusaenys irami (Laurie, 1906), Tanaocheles bidentata (Nobili, 1901), Portunus convexus De Haan, 1835, Xiphonectes macrophthalmus (Rathbun, 1906), Thalamita gatavakensis Nobili, 1906, Serenius ceylonicus (Laurie, 1906), and Soliella flava (Rathbun, 1894) are reported for the first time from Indian waters. Furthermore, the geographical distribution of T.
View Article and Find Full Text PDFThe sponge-associated benthic shrimp Spongicoloides weijiaensis Xu, Zhou & Wang, 2017 is reported for the first time from the Southwest Indian Ridge (SWIR). A single female specimen of S.weijiaensis was associated with the hexactinellid sponge belonging to Dictyaulus sp.
View Article and Find Full Text PDFThe high diversity and endemism of benthic species on seamounts are extensively documented. Although the number of squat lobster species from seamount habitats has increased, species from the Central Indian Ridge (CIR) and Southwest Indian Ridge (SWIR) systems remain largely unknown. The hydrothermally active Indian Ridge system harbours potential sites for future Seafloor Massive Sulphides (SMS) mining.
View Article and Find Full Text PDFTelestula ridgensis sp. nov. is a deep-sea octocoral species collected from the Central Indian Ridges (CIR) seamount.
View Article and Find Full Text PDFDefining the ecological quality of estuaries is challenging because of the inadequacy of available methods and indices to characterise the ecosystem. In Indian estuaries, there are no scientific attempts to establish multi-metric fish index to determine the ecological status. A multi-metric fish index (EMFI) was customised for twelve predominantly open estuaries on India's western coast.
View Article and Find Full Text PDFWe describe a new deep-sea sponge species, Fibulia occiensis sp. nov., from the Central Indian Ocean Ridge (CIOR) at Rodrigues Triple Junction (RTJ), of the family Dendoricellidae Hentschel, 1923.
View Article and Find Full Text PDFDeep-sea sponges are an imperative component of benthos. They accumulate the suspended organic matter by filtering large quantities of water and, with their intricate structures, provide the most suitable habitats for various associated organisms. We describe three new cadorhizid sponges from the Central Indian Ridge (CIR), Indian Ocean.
View Article and Find Full Text PDFMarked by strong El Niño-Southern Oscillation (ENSO) effects during 2014-2016, global coral reefs underwent mass bleaching. Here, we conducted a comprehensive (2014-2019) study, coinciding with the 2014-16 ENSO, to investigate the response and resilience potential of marginal coral communities to the combined impact of recurrent thermal anomalies and multiple anthropogenic stressors before, during, and after the mass bleaching episodes. Our result unveiled that thermal-stress-driven back-to-back annual coral bleaching episodes caused coral mortality and significantly decimated coral cover, primarily in 2015 and 2016.
View Article and Find Full Text PDFInvasive alien species (IAS) influence the trophic organisation and food web structure in an invaded ecosystem, and therefore, it is imperative to quantify the resultant ecological impacts. The globally recognised ecosystem modelling platform, Ecopath with Ecosim, was used to delineate the impacts of IAS on a tropical freshwater pond ecosystem in India. We analysed the trophic interactions, consumption patterns, prey overlap and mixed trophic impacts of three co-existing invasive alien fish species, African catfish (Clarias gariepinus), suckermouth catfish (Pterygoplichthys pardalis) and Mozambique tilapia (Oreochromis mossambicus), on other functional groups in the ecosystem.
View Article and Find Full Text PDFCoastal upwelling that occurs in the eastern Arabian Sea (EAS) drive the complex dynamics of the food chain. Macrofauna plays a key role in the functioning of coastal ecosystems, but few studies explored the taxonomic and functional patterns of macrofaunal communities under the influence of upwelling. These patterns have been investigated in this study by sampling macrofauna and environmental variables during March-December 2012 across six depths (13-100 m) over the continental shelf off Kochi, south EAS.
View Article and Find Full Text PDFThe deep-sea blind lobster A. Milne-Edwards, 1880 was collected at a water depth of 3433 m and is reported for the first time from the Central Indian Ridge (CIR). The species was identified based on morphological examination and supported by mitochondrial Cytochrome Oxidase Subunit I (mtCOI) gene.
View Article and Find Full Text PDFThe bacterial diversity associated with eroding sponges belonging to the Cliona viridis species complex is scarcely known. Cliona thomasi described from the West Coast of India is a new introduction to the viridis species complex. In this study, we determined the bacterial diversity associated with C.
View Article and Find Full Text PDFGlobally, coral reefs have drastically degraded due to local and global environmental stressors. Concurrently, coral reef tourism is rapidly growing in developing economies, which is one of many anthropogenic stressors impacting reefs. At the Malvan Marine Sanctuary, a Marine Protected Area (MPA) on the West coast of India, we investigated the impact of recreational diving on the reef from 2016 to 2019.
View Article and Find Full Text PDFMitochondrial DNA B Resour
September 2019
The honeycomb worm is the most common reef-building polychaete in the intertidal area along the south-eastern Arabian Sea. We used the mitochondrial cytochrome c oxidase subunit I (mtCOI) gene to examine the levels of genetic variation the population. The samples were collected from seven intertidal areas along the south-eastern Arabian Sea.
View Article and Find Full Text PDFGlobally, coral reefs are degrading rapidly due to the combined impact of wide-scale anthropogenic activities and climate change. Similarly, coral reefs in India are facing an existential threat because of intensified environmental degradation, which challenges reef ecosystem resilience and socio-ecological stability. Recently, Govt.
View Article and Find Full Text PDFThe limited DNA sequence data of the polychaetes species are available from the Eastern Arabian Sea. We have sequenced 18S rDNA gene from 54 polychaetes species and 37 species identified up to the species level. The DNA bar-coding data provides for molecular identification of benthic polychaetes that will provide imminent into drivers of species diversity in the Eastern Arabian Sea.
View Article and Find Full Text PDFDiverse biological communities mediate the transformation, transport, and storage of elements fundamental to life on Earth, including carbon, nitrogen, and oxygen. However, global biogeochemical model outcomes can vary by orders of magnitude, compromising capacity to project realistic ecosystem responses to planetary changes, including ocean productivity and climate. Here, we compare global carbon turnover rates estimated using models grounded in biological versus geochemical theory and argue that the turnover estimates based on each perspective yield divergent outcomes.
View Article and Find Full Text PDFThe present study explores the in vivo and in vitro genotoxic effects of lead nitrate, [Pb(NO)] a recognized environmental pollutant and cobalt chloride (CoCl), an emerging environmental pollutant in polychaete Perinereis cultrifera using comet assay. Despite widespread occurrence and extensive industrial applications, no previous published reports on genotoxicity of these compounds are available in polychaete as detected by comet assay. Polychaetes were exposed in vivo to Pb(NO) (0, 100, 500, and 1000 μg/l) and CoCl (0, 100, 300, and 500 μg/l) for 5 days.
View Article and Find Full Text PDFCommercial-scale mining for polymetallic nodules could have a major impact on the deep-sea environment, but the effects of these mining activities on deep-sea ecosystems are very poorly known. The first commercial test mining for polymetallic nodules was carried out in 1970. Since then a number of small-scale commercial test mining or scientific disturbance studies have been carried out.
View Article and Find Full Text PDFSkeletal tissue growth anomalies (STAs) of corals are capable of causing considerable degradation of reef health. This study is the first report of growth anomalies in Turbinaria corals and the first descriptive study of Indian corals. T.
View Article and Find Full Text PDFThe objectives of the present study were to evaluate the ecological status of tropical coastal waters using the temperate benthic indices and examine the effect of seasonal variability on the performance of benthic indices. Macrobenthic samples were collected from northwest to southeast coast of India during 2003-2012 and we tested different univariate indices, ecological strategies, indicator species and multimetric indices. AMBI and multimetric indices performed satisfactorily in evaluating the ecological status.
View Article and Find Full Text PDFMitochondrial DNA A DNA Mapp Seq Anal
September 2016
The complete mitochondrial genome of the Spadenose shark Scoliodon laticaudus has been determined for the first time in this study. It was 16,695 bp in length and consisted of 37 genes with typical gene order in vertebrate mitogenome. The nucleotide base content of S.
View Article and Find Full Text PDFAn ecotoxicological study were conducted to evaluate the concentrations of PAHs and n-alkanes, in gut, liver and kidney tissues of two individuals of Enhydrina schistose (Daudin, 1803), using gas chromatography/mass spectrometry. The concentrations of PAHs (0.10 µg/g) and n-alkanes (8.
View Article and Find Full Text PDFThis paper presents an evaluation of the genotoxic effects of cadmium chloride (CdCl2 ) on marine gastropod, Nerita chamaeleon following the technique of comet assay and the DNA alkaline unwinding assay (DAUA). In this study, the extent of DNA damage in gill cells of N. chamaeleon was measured after in vivo exposure to four different concentrations (10, 25, 50, and 75 µg/L) of CdCl2 .
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