Tuesday, August 10, 2021

[Ichthyology • 2021] Badis kaladanensis • A New Fish Species (Teleostei: Badidae) from Mizoram, northeast India

 Badis kaladanensis
Ramliana, Lalronunga & Singh, 2021

Badis kaladanensis, a new percoid fish is described from the Kaladan basin of Mizoram, northeast India. It belongs to the Badis badis species group but can be easily distinguished from its congeners, except from B. kanabos and B. tuivaiei, in having a dark blotch on the dorsal fin between the base of 3rd to 5th spines. It is further distinguished from B. kanabos in having more scales in lateral row (27–30 vs. 25–26), more circumpeduncular scale rows (18–20 vs. 16–17) and smaller eye (7.5–8.9% SL vs. 9.5–12.7); and from B. tuivaiei in having fewer vertebrae (28–29 vs. 30–31) and more rakers on the first gill arch (9 vs. 6–8). The analysis of the mitochondrial DNA (coi and cytb) revealed the distinctness of B. kaladanensis from all other Badis species with the interspecific distance ranges from 5.4–20.4%. (coi) and 5.1–26.3% (cytb).

Fig 3. Badis kaladanensis
a) holotype, ZSI FF 5404, 48.6 mm SL;
b) Paratype, PUCMF 15002, 45.2 mm SL.

Fig 4. Live individual of Badis kaladanensis. PUCMF 15001, 44.8 mm SL.  

Badis kaladanensis sp. nov.

Diagnosis: Badis kaladanensis is distinguished from its congeners in having the following combination of characters: a post nuchal hump, a conspicuous dark blotch covering superficial part of cleithrum above pectoral-fin base, a dark anterior dorsal-fin blotch between 3rd to 5th spines (consistently present in live and preserved specimens), 27–30 scales in lateral row, 18–20 circumpeduncular scale rows, 28–29 vertebrae, 9 rakers on the first gill arch and lacking a dark blotch on the dorsolateral aspect of caudal peduncle.

Etymology. The species is named after the River drainage, the Kaladan River. An adjective.

Fig 5. Type locality of Badis kaladanensis (Palak River, Mizoram, India).

Distribution and habitat. Known from the Palak River (Fig 5) and Sala River, a tributary of the Kaladan basin, in the vicinity of Phurra village and Lungpuk village respectively in Siaha District of Mizoram, India (Fig 6). It is found associated with Olyra saginata, Pethia expletiforis, Rasbora rasbora and R. daniconius.

Lal Ramliana, Samuel Lalronunga and Mahender Singh. 2021. Badis kaladanensis, A New Fish Species (Teleostei: Badidae) from Mizoram, northeast India.  PLoS ONE 16(7): e0246466. DOI: 10.1371/journal.pone.0246466