Abstract
Little is known about the feeding biology of the sisorid catfish Parachiloglanis hodgarti, a species native to fast-flowing streams across Nepal, India, Bhutan, Bangladesh, Myanmar, and China. In this study, we investigated the feeding anatomy, diet composition, trophic level, and food preferences of 60 specimens collected from three Nepalese streams to elucidate its trophic ecology. Stomach content analysis revealed the presence of insect larvae from the orders Ephemeroptera, Plecoptera, Trichoptera, and Diptera, with the genera Baetis, Hydropsyche, and Neoperla showing the highest Index of Relative Importance (IRI). Morphological characteristics suggest that P. hodgarti relies more on chemosensation (e.g., taste) than vision for prey detection. A low caudal fin aspect ratio (1.58) indicates high maneuverability, likely an adaptation for capturing evasive prey. Additionally, an intestinal coefficient of 0.86, a trophic level of 3.32, and a niche breadth of 0.56 classify P. hodgarti as an insectivore with an intermediate level of dietary specialization.
References
Afifi, M.A.M., M. Fares, W. Shalaby, W.A. Shaeir & H.M.M. KhalafAllah (2024): Morphological, histological and histochemical adaptations in digestive tubular part, concerning the feeding strategy of Skipjack Tuna (Katsuwonus pelamis) inhabiting Abu Galum, Aqaba Gulf, Red Sea, Egypt. Egyptian Journal of Aquatic Biology and Fisheries 28(3): 19–35.
Albrecht, M.P., M.F. Ferreira & E.P. Caramaschi (2001): Anatomical features and histology of the digestive tract of two related Neotropical omnivorous fishes (Characiformes, Anostomidae). Journal of Fish Biology 58: 419–430.
Alves, A.P.C., R.T. Pereira & P.V. Rosa (2021): Morphology of the digestive system in carnivorous freshwater dourado Salminus brasiliensis Journal of Fish Biology 99: 1222–1235.
American Veterinary Medical Association AVMA (2020): AVMA guidelines for the euthanasia of animals (2020) (ed.): https://www.avma.org/resources-tools/avma-opolicies/avmaguidelineseuthanasia-animals.
Amundsen, P.A. & J. Sanchez-Hernandez (2019): Feeding studies take guts – critical review and recommendations of methods for stomach contents analysis in fish. Journal of Fish Biology 95: 1364–1373.
Argillier, C., M. Barral & P. Irz (2003): Growth and diet of the Pikeperch Sander lucioperca (L.) in two French reservoirs. Archives of Polish Fisheries 11(1): 99–114.
Boglione, C., M. Giganti, C. Selmo & S. Cataudella (2003): Morphoecology in larval fin-fish: A new candidate species for aquaculture, Diplodus puntazzo (Sparidae). Aquaculture International 11: 17– 41.
Bowman, R.E. & E.W. Bowman (1980): Diurnal variation in the feeding intensity and catch ability of silver hake (Merluccius bilinearis). Canadian Journal of Fisheries and Aquatic Sciences 37: 1565–1572.
Briones, J.C., C.H. Tsai, T. Nakazawa, Y. Sakai, R.D. Papa & C.H. Hsieh (2012): Long-term changes in the diet of Gymnogobius isaza from Lake Biwa, Japan: Effects of body size and environmental prey availability. PLoS One 7(12): e53167.
Chapman, L.J., W.C. Mackay & C.W. Wilkinson (1989): Feeding flexibility in northern pike (Esox lucius): Fish versus invertebrate prey. Canadian Journal of Fisheries and Aquatic Sciences 46: 666–669.
Christensen, V. & D. Pauly (1992): ECOPATH II – a software for balancing steady-state ecosystem models and calculating network characteristics. Ecological Modelling 61: 169–185.
Desai, V.R. (1970): Studies on the fishery and biology of Tor tor (Hamilton) from river Narbada. Journal of the Inland Fisheries Society of India 2: 101–112.
Devi, R. & N. Boguskaya (2009): ‘Parachiloglanis hodgarti’. The IUCN Red List of Threatened Species 2009: e.T166618A6248603. Accessed on May 24, 2025.
Edds, D.R. (1987): Foods of some Nepalese fishes. Journal of Natural History Museum (Nepal) 11: 1–14.
Euzen, O. (1987): Food habits and diet composition of some fish of Kuwait. Kuwait Bulletin of Marine Science 9: 65–85.
Fryer, G. & T.D. Iles (1972): The Cichlid Fishes of the Great Lakes of Africa. Their Biology and Evolution. Oliver and Boyd, Edinburgh.
Geerinckx, T., J. De Poorter & J. Adriaens (2007): Morphology and development of teeth and epidermal brushes in loricariid catfishes. Journal of Morphology 268: 805–814.
Ghosh, S.K. & P. Chakrabarti (2015): Histological and histochemical characterization on stomach of Mystus cavasius (Hamilton), Oreochromis niloticus (Linnaeus) and Gudusia chapra (Hamilton): Comparative study. The Journal of Basic and Applied Zoology 70: 16–24.
Grossman, G.D. (1986): Food resource partitioning in a rocky intertidal fish assemblage. Journal of Zoology 1: 317–355.
Hamrin, S.F. & L. Persson (1986): Asymmetrical competition between age classes as a factor causing population oscillations in an obligate planktivorous fish species. Oikos 47: 223–232.
Horn, M.H. (1998): Feeding and Digestion. Pp. 43–63. In: Evans, D.H. (Ed.): The Physiology of Fishes, Second edition. CRC Press, New York.
Hurlbert, S.H. (1978): The measurement of niche overlap and some relatives. Ecology 59: 67–77.
Hynes, H.B.N. (1950): The food of fresh-water sticklebacks (Gasterosteus aculeatus and Pygosteus pungitius), with a review of methods used in studies of the food of fishes. Journal of Animal Ecology 19: 36–58.
Hyslop, E.J. (1980): Stomach contents analysis – a review of methods and their application. Journal of Fish Biology 17: 411–429.
Imms, A.D. (1957): A General Textbook of Entomology: Including the Anatomy, Physiology, Development and Classification of Insects, Ninth edition, Dutton & Co., New York.
Jardas, I., M. Šantić & A. Pallaoro (2004): Diet composition and feeding intensity of horse mackerel, Trachurus trachurus (Osteichthyes: Carangidae) in the eastern Adriatic. Marine Biology 144: 1051–1056.
Jayaram, K.C. (2010): The Freshwater Fishes of the Indian Region. Revised Second Edition, Narendra Publishing House, Delhi.
Kapoor, B.G. & S.S. Khanna (1994): The alimentary canal of teleosts: A brief survey of structure and function. Pp. 12–24. In: Singh, H.R. (Ed.): Advances in Fish Biology, Hindustan Publishing Corporation, Delhi.
Karachle, P.K. & K.I. Stergiou (2010): Intestine Morphometrics of Fishes: A Compilation and Analysis of Bibliographic Data. Acta Ichthyolgica Et Piscatoria 40(1): 45–54.
Kassim, Z., M.S. Majid, N.Y.M. Alwi & H.H. Hasnan (2018): Diet preferences of small fishes at Setiu Lagoon, Malaysia. Ecology and Sustainable Development 1: 9–17.
Kramer, D.L. & M.J. Bryant (1995): Intestine length in the fishes of a tropical stream: 1. Ontogenetic allometry. Environmental Biology of Fishes 42: 115–127.
Levins, R. (1968): Evolution in Changing Environments: Some Theoretical Explorations. No. 2. Princeton University Press, Princeton, NJ, USA.
McCune, B. & J.B. Grace (2002): Analysis of Ecological Communities. MjM Software Design, Gleneden Beach, OR, USA.
Odum, W.E. (1970): Utilization of the direct grazing and plant detritus food chains by the striped mullet Mugil cephalus. Pp. 222–240. In: Marine Food Chains. Steel, J.H. (Ed.). Oliver and Boyd, Edinburgh.
Ono, D.R. (1980): Fine structure and distribution of epidermal projections associated with taste buds on the oral papillae in some loricariid catfishes (Siluroidei: Loricariidae). Journal of Morphology 164: 139–159.
Papadimitraki, M., K. Maar & S.H. Jónasdóttir (2023): Meso- and bathypelagic fish feeding ecology: A meta-analysis on fatty acids and stable isotope trophic studies. Deep Sea Research Part I: Oceanographic Research Papers 198: 104083.
Pauly, D. (1990): Food consumption by tropical and temperate marine fishes: Some generalizations. Journal of Fish Biology 35:11–20.
Pinkas, L., M.S. Oliphant & I.L.K. Iverson (1971): Food habits of albacore, bluefin tuna and bonito in California waters. Fish Bulletin 152:1 and bonito in California waters. Fish Bulletin 152: 1–105.
Rodrigues, S.S. & E. Menin (2008): Anatomia do tubo digestivo de Salminus brasiliensis (Cuvier, 1817) (Pisces, Characidae, Salmininae). Biotemas 21(2): 65–75.
Sambilay Jr., V.C. (1990): Interrelationships between swimming speed, caudal fin aspect ratio and body length of fishes. Fishbyte 8(3): 16–20.
Schneider, C.A., W.S. Rasband & K.W. Eliceiri (2012): NIH Image to ImageJ: 25 years of image analysis. Nature Methods 9: 671–675.
Segurado, P., J.M. Santos, D. Pont, A.H. Melcher, D.G. Jalon, R.M. Hughes & M.T. Ferreira (2011): Estimating species tolerance to human perturbation: Expert judgment versus empirical approaches. Ecological Indicators 11: 1623–1635.
Shalaby, W. (2020): Comparative morphological and histological studies on the adaptation of esophagus and stomach to the feeding habits in some coral reef fishes at Hurghada, Red Sea, Egypt. Egyptian Journal of Aquatic Biology and Fisheries 24: 289–306.
Shrestha, J. (2011): Threat Status of Indigenous Fish Species of Nepal. In: Wagle, S.K. and N. Pradhan (Eds): Proceedings of the consultative workshop on fish conservation in Nepal, Fisheries Research Division (FRD), Godawari, Lalitpur, Nepal Agricultural Research Council (NARC)
Shrestha, T.K. (2019): Ichthyology of Nepal. B.J. Shrestha, publisher, Kathmandu.
Sinha, M. (1986): Functional morphology, anatomy and histology of the digestive organs of the catfish Plotosus canius Hamilton. Proceedings: Animal Sciences 95: 23–44.
Sirotenko, M. & A. Istomin (1978): Seasonal variations in the feeding of the Black Sea Trachurus mediterraneus ponticus Aleev. Journal of Ichthyology 18: 424–431.
Subramanian, K.A. & K.G. Sivaramakrishnan (2007): Aquatic Insects of India – A Field Guide. Ashoka Trust for Ecology and Environment (ATREE), Bangalore, India.
Talwar, P.K. & A.G. Jhingran (1991): Inland Fishes of India and Adjacent Countries. Oxford and IBH Publishing Co., Delhi.
Thoni, R.J. & D.B. Gurung (2014): Parachiloglanis bhutanensis, a new species of torrent catfish (Siluriformes: Sisoridae) from Bhutan. Zootaxa 3869(3): 306–312.
Tikkanen, P., T. Muotka & A. Hubta (1994): Predator detection and avoidance by lotic mayfly nymphs of different size. Oecologia 99: 252–259.
Wang, C.A., J.Z. Ma, Q.Y. Xu, J.S. Yin, J.N. Li, L.S. Wang, Z.G. Zhao & L. Luo (2016): The development of pharyngeal taste buds in Hucho taimen (Pallas, 1773) larvae. Iranian Journal of Fisheries Science 15: 426–435.
Wilson, J.M. & L.F.C. Castro (2010): Morphological diversity of the gastrointestinal tract in fishes. Pp. 1–55. In: Grosell, M., A.P. Farrell & C.J. Brauner (Eds). Fish Physiology: The Multifunctional Gut of Fish. Academic Press, San Diego, CA, USA.