Smrithy Raj

• PhD Student at University of Kerala

An integrative taxonomic study on the gobioid fishes of Ashtamudi Lake (a Ramsar Site), Kerala, India revealed the occurrence of 12 species representing 10 genera, including three species of the genus Oxyurichthys. The Arrowfin goby, Oxyurichthys tentacularis, considered as the mainstay of gobioid fisheries in the Lake for over 40 years, represents...

Understanding the dynamics between native and invasive species in aquatic ecosystems is crucial for effective conservation and management. This study investigates the diet composition and niche overlap of the native paradise fish (Pseudosphromenus dayi) and the introduced three-spot gourami (Trichopodus trichopterus) in a coastal wetland in Kerala,...

Purpose Specimens of Elthusa from trashfish of the Indian SW coast were described as a new parasitic cymothoid, Elthusa nemo sp. nov., (Crustacea: Isopoda). Later, the branchial cavity of the Blotchfin dragonet Callionymus filamentosus Valenciennes, 1837 were documented as its micro- and macro-habitat (host). Methods Fresh/live specimens of uniden...

A new branchial fish parasitic cymothoid species, Elthusa aquabio sp. n. (Crustacea: Isopoda: Cymothoidae), is described based on the ovigerous female collected from an unknown host obtained from trash fishes from the south-west coast of India. The species Elthusa aquabio sp. nov. has the following characteristics: (1) body slightly twisted, elonga...

One new genus and two new species of semiterrestrial freshwater crabs are described from the Southern Western Ghats mountain range in India: Pavizham gavi gen., sp. nov. and Rajathelphusa brunnea sp. nov. The carapace of Pavizham n. gen. is superficially similar to Baratha and Snaha described from the same region, but it can be distinguished from B...

Abstract: The present paper deals with the breeding biology of the invasive fish Pterygoplicthys pardalis from the natural drainages of Thiruvananthapuram, Kerala. The specimens were collected from Amayizhanchan Thodu, a natural drainage running through the heart of the city. A total of 145 males and 142 females were collected from January to Decem...

The present paper deals with the breeding biology of the invasive fish Pterygoplicthys pardalis from the natural drainages of Thiruvananthapuram, Kerala. The specimens were collected from Amayizhanchan Thodu, a natural drainage running through the heart of the city. A total of 145 males and 142 females were collected from January to December 2018....

Focusing on extreme climatic events in India’s Western Ghats Biodiversity Hotspot, we demonstrate that unmanaged aquaculture and unregulated fisheries can often combine with ECE in exacerbating biological invasions through the unexpected introduction and escape of novel alien species. High magnitude flooding events in August 2018 and 2019 resulted...

The threat posed by invasive non-native species worldwide requires a global approach to identify which introduced species are likely to pose an elevated risk of impact to native species and ecosystems. To inform policy, stakeholders and management decisions on global threats to aquatic ecosystems, 195 assessors representing 120 risk assessment area...

A new genus of freshwater crab, Rajathelphusa gen. nov., and two species, R. ala sp. nov. (type species) and R. muni sp. nov., are described from the Kerala part of the Western Ghats biodiversity hotspot, India. The new genus is superficially similar to Arcithelphusa and Cylindrotelphusa from the same hotspot, but can easily be distinguished by the...

We present results of the first major attempt to record the distribution of aquatic alien species in the Western Ghats Biodiversity Hotspot using Geographical Information System. A total of 32 alien species, including four macrophytes (Salvinia molesta, Pistia stratiotes, Eichhornia crassipes and Cabomba furcata) and 28 fish were recorded from the...

Abstract Gut contents of the exotic characid fish Piaractus brachypomus (Cuvier, 1818) that escaped into the Vembanad-Kole Wetland, India, during the floods were examined for their gut food spectrum. The qualitative analysis of gut contents showed that the fish is an omnivore with detritus (27 %) as the most dominant food item followed by, plant m...

Gut contents of the exotic characid fish Piaractus brachypomus (Cuvier, 1818) that escaped into the Vembanad-Kole Wetland, India, during the floods were examined for their gut food spectrum. The qualitative analysis of gut contents showed that the fish is an omnivore with detritus (27 %) as the most dominant food item followed by, plant matter (25...

A mass balanced trophic model was constructed for Sasthamkotta Lake, a Ramsar site in Kerala, India to study the energy flows and species interactions among fourteen key functional groups in the lake. The functional groups considered were fish

Invasion of armoured catfish, Pterygoplichthys spp., is a major threat to global aquatic biodiversity, and developing effective strategies for their control and eradication is both a concern and a research priority. A length‐based population assessment of invasive Pterygoplichthys pardalis in southern India, a hotspot for endemic aquatic biodiversi...

Jurassic invaders: flood-associated occurrence of arapaima and alligator gar in the rivers of Kerala: Opinion on the post-flood introduction of Arapima and Alligar gar fish in the natural water bodies of Kerala, India and suggestions on management.

Loricariid catfishes of the genus Pterygoplichthys are native to South America and have been introduced in many localities around the world. They are freshwater fishes, but may also use low-salinity habitats such as estuaries for feeding or dispersal. Here we report results of a field survey and salinity-tolerance experiments for a population of Pt...

Loricariid catfishes of the genus Pterygoplichthys are native to South America and have been introduced in many localities around the world. They are freshwater fishes, but may also use low-salinity habitats such as estuaries for feeding or dispersal. Here we report results of a field survey and salinity-tolerance experiments for a population of Pt...

Kerala is the largest freshwater crab-rich state in India. Out of 120 species of Indian freshwater crabs, Kerala is home for 35 gecarcinucid species (nearly 30%) in 14 genera. The Kerala part of the Western Ghats includes 26 species, which is about 45% of the total species (58 species) in the Western Ghats of India. Moreover, nearly two-thirds spec...

Kerala is the largest freshwater crab-rich state in India. Out of 120 species of Indian freshwater crabs, Kerala is home for 35 gecarcinucid species (nearly 30%) in 14 genera. The Kerala part of the Western Ghats includes 26 species, which is about 45% of the total species (58 species) in the Western Ghats of India. Moreover, nearly two-thirds spec...

A new species of gecarcinucid freshwater crab of the genus Oziotelphusa Müller, 1887, is described from stationary or slow-flowing bodies of water in Keeriparai near Nagercoil, in the state of Tamil Nadu in southern India. Oziotelphusa ravi, new species, is distinguished from its congeners by several distinct characters: the median tooth of the pos...

A new genus of freshwater crab, Karkata gen. nov., with two species, K. ghanarakta sp. nov. (type species) and K. kusumbha sp. nov., and two new species each of Pilarta Bahir and Yeo, 2007 (P. aroma sp. nov. and P. punctatissima sp. nov.) and Cylindrotelphusa Alcock, 1909 (C. breviphallus sp. nov. and C. longiphallus sp. nov.), are described from K...

A new genus and new species of tree crab is described from the Western Ghats biodiversity hotspot in Kerala, southern India. Kani maranjandun. gen., n. sp., is substantially different from all congeners in a suite of characters, notably the diagnostic carapace and male abdominal structure, as well as the conspicuously elongated ambulatory legs. The...

The present study discusses the Length-Weight Relationship, Condition factor (K) and Relative condition factor(Kn)of the aliencatfish Clarias gariepinus(Burchell, 1822)from Mattupetty reservoir, one of the premier reservoirs located at the high altitude terrains of Kerala. A total of 52 individuals were measured,size ranging from 16 to 63 cm (SL)an...

Nilotic tilapia, one of the important invasive alien species (IAS) of inland waters of Kerala, a southwestern state in India attracted attention due to many factors including beneficial as well as detrimental factors like its aquaculture potential and its invasive and/or destructive nature respectively. Nile tilapia is reared extensively due to its...

This paper documents the occurrence of the exotic South American suckermouth armoured catfishes (Loricariidae) of the genus Pterygoplichthys spp. in the drainages of Thiruvananthapuram City, Kerala. The morphological taxonomy revealed that the specimens are closely related to Pterygoplichthys disjunctivus (Weber, 1991) and P. pardalis (Castelnau, 1...

This paper documents the occurrence of the exotic South American suckermouth armoured catfishes (Loricariidae) of the genus Pterygoplichthys spp. in the drainages of Thiruvananthapuram City, Kerala. The morphological taxonomy revealed that the specimens are closely related to Pterygoplichthys disjunctivus (Weber, 1991) and P. pardalis (Castelnau, 1...

A mass balanced ecosystem model was constructed for Vellayani freshwater lake in India using Ecopath with Ecosim software. Both grazing and detrital food chains were found to be equally important. Highest omnivory index was recorded for the Indian major carps, stocked recently, indicating their effective utilization of the available niches. The eco...

This paper documents the traditional cast net fishery prevailing in the Ashtamudi Estuary situated along the south-west coast of India, taking advantage of the behavioural patterns of Indo-Pacific humpback dolphin, Sousa chinensis (Osbeck, 1765). The feeding-related behaviours noted were sudden rush towards the prey with shuttling or speedy zigzagg...

This paper documents the behaviour of Indo-Pacific humpback dolphin, Sousa chinensis (Osbeck) found in the Ashtamudi estuary situated along the southwest coast of India. The major foraging strategy of the dolphins observed was beach hunting. The feeding-related behaviours noted were sudden bout towards the prey with shuttling or speedy zigzagging b...

Spatio-temporal shift of nutrients due to Lakkidi Check dam in Bharathapuzha river