Sandhya Sukumaran

• Doctor of Philosophy
• Principal Scientist at Central Marine Fisheries Research Institute

There is considerable evidence that genetic damage in organisms occurs in the environment as a result of exposure to genotoxins and ionising radiation, but we have limited understanding of the extent to which this results in adverse consequences at a population level. We used inter-simple sequence repeat (ISSR) markers to quantify genotoxic effects...

Oceans are vast, dynamic, and complex ecosystems characterized by fluctuations in environmental parameters like sea surface temperature (SST), salinity, oxygen availability, and productivity. Environmental variability acts as the driver of organismal evolution and speciation as organisms strive to cope with the challenges. We investigated the evolu...

The Indian oil sardine, Sardinella longiceps , is a widely distributed and commercially important small pelagic fish of the Northern Indian Ocean. The genome of the Indian oil sardine has been characterized using Illumina and Nanopore platforms. The assembly is 1.077 Gb (31.86 Mb Scaffold N50) in size with a repeat content of 23.24%. The BUSCO (Ben...

Mytella strigata, a potentially invasive species native to South America, is rapidly spreading across various aquatic ecosystems around the globe, posing a threat to native mussels. This study presents the first comprehensive de novo transcriptome assembly of M. strigata. We generated 254 million reads, which were processed and assembled using the...

Mussels, particularly Perna viridis, are vital sentinel species for toxicology and biomonitoring in environmental health. This species plays a crucial role in aquaculture and significantly impacts the fisheries sector. Despite the ecological and economic importance of this species, its omics resources are still scarce. We generated a gill-specific...

A new species of eight‐gilled hagfish genus Eptatretus (Myxinidae) is described based on five specimens trawled on the upper continental slope off Kollam, Kerala, India, northern Indian Ocean. Eptatretus gopali sp. nov. can be diagnosed by the presence of eight‐gill pouches and gill apertures, 10–11 pre‐brachial, 7 branchial, 50–55 trunk, 9–10 tail...

The Indian scad, Decapterus russelli is one of the most exploited pelagic resources of India. Population genetic analyses using mitochondrial and nuclear markers indicated a lack of genetic structuring among populations from Indian waters. As this species is highly migratory, it is also important to establish the environmental influence on its popu...

Cephalopods have dominated the oceans for hundreds of millions of years and are unquestionably at the peak of molluscan evolution. The development of the large brain and a well-sophisticated sensory system contributed significantly to its success. Therefore, it is considered the best example of convergent evolution and attracted the attention of sc...

We characterized the complete mitogenome of Nemip-terus randalli and performed comparative mitogenomic analysis with previously determined mitochondrial geno-mes belonging to the family Nemipteridae. Using Sanger sequencing, we identified a 16,642 bp mitogenome containing 37 genes (13 protein-coding, 2 rRNA, 22 tRNA) and a non-coding region. Its ge...

Pangio juhuae sp nov, a new species of subterranean eel loach, is described from Kerala, India. It is distinguished from its subterranean congeners by the presence of a dorsal fin, four pectoral rays and five segmented anal fin rays. Genetic analyses suggest that P. juhuae is closely related to P. bhujia but is distinct in morphology, particularly...

The Asian green mussel, Perna viridis is an important aquaculture species in the family Mytilidae contributing substantially to molluscan aquaculture. We generated a high-quality chromosome level assembly of this species by combining PacBio single molecule sequencing technique (SMRT), Illumina paired-end sequencing, high-throughput chromosome confo...

India is one of the major fishing nations in the Indian Ocean, with commercial marine fishlandings in the country comprising of nearly 1000 species. A comprehensive and periodicassessment of the stocks is crucial for achieving the goals of sustainable fisheries harvestand management. The ICAR-Central Marine Fisheries Research Institute, Ministry of...

Nemipterus randalli, commonly known as Randall’s threadfin bream, is a commercially important marine finfish. Understanding its genetic structure is critical to effective management and conservation efforts. Previous investigations on population structure in this species were limited by geographic coverage. In this study, we utilized the mitochondr...

Sharks have thrived in the oceans for 400 million years, experienced five extinctions and evolved into today’s apex predators. However, enormous genome size, poor karyotyping and limited tissue sampling options are the bottlenecks in shark research. Sharks of the family Orectolobiformes act as model species in transcriptome research with exceptiona...

The blue economy, encompassing sustainable utilization of coastal and oceanic resources, has gained global significance in the context of the developing discourse on economic growth and environmental conservation in ocean-based economies. This article delves into the multifaceted realm of India's fisheries and coastal aquaculture sectors, exploring...

Stock assessments of fish stocks are critical for framing effective management measures of fishery resources to ensure sustainability. While species-wise national assessments have been done in the past, India has has now a prioritized list of 196 commercially important species/resources to be assessed regularly to provide an index of the health of...

Stock assessments of fish stocks are critical for framing effective management measures of marine fishery resources to ensure sustainability. In a first of its kind for the country, a marine fish stock status (MFSS) report of India was published recently by CMFRI in 2023. The MFSS report indicated the sustainability status of 70 important species,...

The Indian Scad, Decapterus russelli is an important pelagic carangid widely distributed throughout the Indian Ocean and the Indo-West Pacific. Despite being widely distributed in the Indian Ocean, the information regarding genetic structuring and diversity has been lacking compared to its Indo Malay Archipelago counterparts. The present study was...

Goatfishes (Family: Mullidae) are commercially important fishery resource along the Chennai coast, south-eastern India.Species-level identification of goatfishes is a challenge, particularly in the ‘vittatus’ group, as there is severe overlapof taxonomic characteristics. In 2010, Uiblein and Heemstra revised the Family Mullidae and reported the occ...

Historically India has been projected as one of the major elasmobranch fishing nations in the world. However, management and conservation efforts are not commensurate with this trend. Along with the Wildlife (Protection) Act, 1972, several generic conservation measures are in place at the regional/local level. But India is still a long way from mee...

Globally, many of the Elasmobranch species are threatened with extinction due to their vulnerable life history traits, habitat alterations, overexploitation, and climate change. The Spadenose shark, Scoliodon laticaudus Müller & Henle, 1838, is an amphidromous coastal shark that exhibits placental viviparity. The latest IUCN Red List of Threatened...

A new species of hagfish, Eptatretus wadgensis sp. nov., is described from the Wadge Bank, Lakshadweep Sea, India, obtained from a depth of ~250–300 m through deep-sea trawling. It is diagnosed by having six pairs of gill pouches and gill apertures, 3/3 multicusp teeth, total slime pores 67–69, six branchial slime pores, and ventral aorta bifurcati...

This study was aimed to test the effects of lysine (Lys) and methionine (Met) intake at different dietary protein levels (36, 38, and 40 g/100 g crude protein) on growth and metabolism in the juveniles of silver pompano (Trachinotus blochii). The experiment comprised six diets with different protein levels (CP 36, 38, and 40 g/100 g) without (D1, D...

The phylogenetic relationships of inshore squid species in the family Loliginidae is still ambiguous owing to the lack of morphological and molecular data. In the present study, the taxonomic status of squid species Uroteuthis duvaucelii (Orbigny, 1848), Uroteuthis edulis (Hoyle, 1885), Uroteuthis singhalensis (Ortmann, 1891) and Loliolus hardwicke...

Carangids are abundant and commercially important marine fish that contribute to a significant portion of the fisheries in many parts of the world. In the present study, we characterized the complete mitogenome of the Indian scad, Decapterus russelli and performed a comprehensive comparative mitogenomic analysis of the family Carangidae. The compar...

Fanged sea bream, Sparidentex jamalensis Amir et al. (Pak J Zool 46(2):471–477, 2014) has been recently recorded for the first time in Indian waters from Korapuzha, Kadalundi and Moorad estuaries, Calicut, Kerala. Previously this species was reported only from Pakistan waters globally and till date there are no other reports available on the distri...

Ambiguity regarding the identification of Indo-Pacific sergeant Abudefduf vaigiensis (Quoy and Gaimard, 1825) was sought out through classical taxonomic approach along with molecular confirmation. DNA barcoding of 650 bp region of the Cytochrome C oxidase 1 gene revealed the confirmation of taxonomical identity of the species from the region. Lengt...

Clupeoid fish can be considered excellent candidates to understand the role of mitochondrial DNA in adaptive evolution, as they have colonized different habitats (marine, brackish, freshwater, tropical and temperate regions) over millions of years. Here, we investigate patterns of tRNA location, codon usage bias, and lineage-specific diversifying s...

Aim: The study was carried out to ascertain whether morphotype of Scomberoides commersonnianus (Talang queenfish) existing along the Indian coast is a new species or not. Methodology: Talang queenfish and the morphotype were tested for their uniqueness using systematic and molecular tools. The morphometric and meristic details including otolith mor...

Indian coastline is bestowed with a rich diversity of molluscan species of which mussels belonging to the genus Perna (Family; Mytilidae) occupy a major position. Aquaculture importance of these species is globally recognized. They are extensively used as pollution indicators as they can accumulate contaminants at levels higher than that present in...

The adaptive genetic variation in response to heterogeneous habitats of the Indian Ocean was investigated in the Indian oil sardine using ddRAD sequencing to understand the subpopulation structure, stock complexity, mechanisms of resilience, and vulnerability in the face of climate change. Samples were collected from different ecoregions of the Ind...

The vertebrate mitochondrial genome is characterized by an exceptional organization evolving towards a reduced size. However, the persistence of a non-coding and highly variable control region is against this evolutionary trend that is explained by the presence of conserved sequence motifs or binding sites for nuclear-organized proteins that regula...

Family Sparidae is represented by ten species in Indian waters of which genus Acanthopagrus encompass three species namely, Acanthopagrus berda, A. latus and A. bifasciatus. Present study reveals regular catch of A. berda in different parts of Malabar coast, Kerala from Korapuzha, Kadalundi and Moorad estuaries and through conventional taxonomic as...

Etroplus suratensis is one of the most important indigenous Cichlids of the Indian subcontinent exhibiting restricted distribution in the estuaries of peninsular India and Sri Lanka. Coastal pollution and climate change contribute to the deterioration of their habitats. Etroplus suratensis is widely distributed along estuaries and brackishwater lak...

Sharks are undergoing population declines worldwide and it is imperative to devise conservation and management strategies to prevent their extinction. Oceanic whitetip sharks are large pelagic sharks distributed circumglobally and recent IUCN assessments classified them as “critically endangered.” Considering their vulnerability, we investigated th...

A new species of snake eel Xyrias anjaalai sp. nov. (Anguilliformes: Ophichthidae) is described from morphological analysis of 12 specimens and molecular analysis of four specimens, caught off Kollam, Kerala, southwestern India, by deep-sea trawling. X. anjaalai is distinguished from its congeners by having a large eye diameter, a short snout, a di...

Mitochondrial genomes are valuable for making inferences regarding population genetics, phylogenetics and recently in understanding adaptive variation in OXPHOS genes. Ribbon fish, Trichiurus lepturus is distributed in the Indian Ocean and contributes to a major share of pelagic fish landings. Considering the importance, we characterized the comple...

The scalloped hammerhead shark, Sphyrna lewini (Griffith and Smith, 1834), is an important species along the Indian coast both in the Arabian Sea and Bay of Bengal. As per the IUCN Red List Assessment, the scalloped hammerhead shark is categorized as “globally endangered.” We investigated the intra-specific genetic diversity and population genetic...

Hybridisation of marine ornamental clown anemone fish Amphiprion percula (female) and False clown anemone fish Amphiprion ocellaris (male) were carried out for the production of hybrid clownfishes under captivity. The broodstocks for the present study were selected from the juvenile produced in the Marine Hatchery of CMFRI, Kochi. After attaining 1...

The green chromide Etroplus suratensis (Bloch, 1790), is a cichlid species which forms an economically valuable food fish and a preferred candidate for brackishwater aquaculture in India. The complete mitogenome of E. suratensis collected from Vembanad Lake, Kerala, India has been characterised in the present study. The entire mitogenome was PCR am...

Nine specimens (584–670 mm standard length) of Ariomma brevimanum (Klunzinger 1884) were collected from the Cochin Fishing Harbour (south-eastern Arabian Sea) in 2016. Morphometric and meristic parameters, along with the DNA barcoding confirmed the identity of the specimens. The majority of the proportional morphometric measurement and meristic cou...

We analyzed intraspecific diversity of Indian anchovy, Stolephorus indicus, a commercially and ecologically important species, using mitochondrial DNA markers so as to derive insights into population structuring and historical demography. Analyses were carried out on 128 and 138 individuals collected from 5 locations along the range of distribution...

The occurrence of Bennett’s stingray, Hemitrygon bennettii (Müller et Henle, 1841), is confirmed from Indian waters, based on a single male specimen (370 mm DW) collected from Visakhapatnam, western Bay of Bengal on 28 January 2017. Existing, updated reports on the distribution of the species, places it in the Indo-Pacific region with the western l...

Paphia malabarica Chemnitz, 1782 is an economically important species of Venerid clam in Indian waters. The fishery of P. malabarica from Ashtamudi estuary, Kollam, Kerala has been certified by marine stewardship council as sustainable and the fishery is now managed by a set of fishery management plans. The name P. malabarica is invalid now as it h...

The Indian oil sardine Sardinella longiceps Valenciennes is the most important single species marine fishery resource landed along the Indian coast in terms of volume in catches. It contributes 17 to 20% to the total marine fish landings in India, bulk of which is from the south west coast (Kerala, Karnataka and Goa). The resource is susceptible to...

The present study reports the complete sequences of Aquaporin 1 (AQP1) gene and partial sequences of genes, Sodium/potassium-transporting ATPase subunit alpha-1 (Na/K-ATPase α1 subunit), Osmotic Stress Transcription Factor 1 (OSTF1), Transcription Factor II B (TFIIB), Heat Shock Cognate 71 (HSC71) and Heat Shock Protein 90 (HSP90) obtained from mRN...

The Indian oil Sardine, Sardinella longiceps and Goldstripe Sardinella, Sardinella gibbosa are the two commercially important, small pelagic fishes from Indian waters belonging to the family Clupeidae. Characterization of the complete mitogenome is very helpful in resolving taxonomic ambiguities and hence we characterized the complete mitogenome of...

Indian oil sardines, commercially and ecologically important pelagic fishes in Indian waters have not been the focus of major genetic studies as compared to their counter parts in Atlantic and Pacific oceans in spite of several reports suggesting stock complexity and intraspecific diversity. Hence, we investigated the genetic stock structure of Ind...

A new species of Apocyclops Lindberg (Cyclopoda: Cyclopoida: Cyclopidae) is described based on specimens collected from marine waters of Karwar, Karnataka, India. At present, there are 11 valid and accepted species excluding one extinct species (fossil) in this genus which are widely distributed in fresh and brackishwater areas in the tropics and s...

An attempt was conducted to understand the genetic population structure and historic demography of Indian mackerel, Rastrelliger kanagurta from Indian peninsular waters using mitochondrial DNA markers. A total of 241 sequences of mitochondrial control region and 271 sequences of mitochondrial ATPase gene region were amplified and analyzed in Indian...

Scomber indicus, a new species of mackerel is described based on the specimens collected from the eastern Arabian Sea. The species is differentiated from its nearest congener Scomber australasicus, in having 29-32 gill rakers on lower limb of first gill arch, posteriormost part of hypohyal blunt, with presence of a pit between the hypohyal and the...

The longtail butterfly ray, Gymnura poecilura, was originally described as Raja poecilura by Shaw 1804 without any type material, based on Russell’s (1803) illustration of “Tenkee kunsul” from Vizagapatam (present day Visakhapatnam), India. Because of the absence of detailed taxonomic accounts for G. poecilura, characters mentioned for its identifi...

The Indian oil sardine, Sardinella longiceps, is an important pelagic species in Indian waters, and shows divergent morphology while in sympatry. The reasons behind this divergent morphology were investigated using morphometric, genetic and nutritional analyses. Twenty-one morphometric characters (as percentage of standard length) and eight meristi...

A new species of Harpadon Lesueur, 1825 captured from the continental slope area 19 degrees 53' N - 69 degrees 23' E (north-eastern Arabian Sea) is described. The species Harpadon nudus sp. nov. was identified possessing a prominent trilobed caudal fin and a wide mouth with strong fang like barbed teeth and has been distinguished from its congeners...

A detailed study aimed at identifying the changes in biodiversity, live coral cover as well as health status of the Palk Bay Reef corals was carried out over a period of 4 years. The live coral percent cover was measured using Line Intercept Transect method at fixed sites in the reefs of Palk Bay in 2008 in order to study and make comparisons with...

Velapertumuni Reef, a fringing reef of Palk Bay was surveyed for the assessment of the coral cover and biodiversity during September 2004, following the Line Intercept Transect Method and their geographical positions were fixed using the Global Positioning System. The percentages of live and dead coral cover at each site were derived and a total of...

This paper gives the results of the surveys conducted in the Krusadai Reef for the assessment of the coral cover and biodiversity during March-May 2005, following the Line Intercept Transect Method. A total of 35 hard coral species were recorded in this reef. The total live, dead and bleached coral cover for the reef as a whole was estimated as 54....