First report of anguilliform catfish Olyra praestigiosa Ng & Ferraris 2016 from the state of Arunachal Pradesh, a biodiversity hotspot

Olyra praestigiosa, an anguilliform catfish was first described exclusively from Darjeeling Himalayas of north Bengal. However, during an ichthyological survey along Tissa river system from February 2023 to April 2024, 8 individuals of Olyrids were collected from 7 distinct sampling locations which were later identified as O. praestigiosa. Additionally revealing it’s occurrence very distant from the original type locality of Chel river in West Bengal. Consequently signifying the first report of O.praestigiosa from the state of Arunachal Pradesh. It is defined by having an anguilliform body, first and second dorsal fin rays being non-ossified as well as the upper caudal fin lobe being significantly expanded. A comparison of morphological characteristics of Olyra praestigiosa specimens collected from the Tissa River system with the original description of O. praestigiosa available in the literature revealed slight variation in dorsal fin to adipose fin distance as well as wider range of adipose fin base length in proportion to it’s standard length. Additionally the altitudinal range of its distribution was expanded from 382 m in type locality to 212 – 919 m in Tissa river originating in the Indo-Myanmar borders.