Matt Clarke looks at the Assamese kingfish, Cyprinion semiplotum (aka Semiplotus semiplotus), a newly imported giant cyprinid from south Asia.
Common name: Assamese kingfish, Emperor fish
Scientific name: Cyprinion semiplotum (McLelland 1839)
Origin: India, Malaysia, Myanmar (Burma) and Nepal. According to Talwar and Jhingran (1991) it's also been recorded in Bhutan. Indian fish expert Andrew Arunava Rao, who collects fish for the trade, tells me he catches them in the Kalikhola, Sankosh River, Indo-Bhutan border, Jalpaiguri Distict, in North West Bengal.
Size: A heavy and stocky 60cm/24".
Diet: Specific diet not known but the mouth suggests a grazer. Andrew says that they feed ravenously, but may fast for a couple of days after addition to a new aquarium.
Aquarium: This large fish reaches similar proportions to the Common carp, so it really demands a very large aquarium. Based on the adult size, you'd need something of around 3m/10' in length for this species to live in comfort, so it's not a particularly good fish for the aquarium. Hardly anything is known about the captive care of any Cyprinion species. Andrew told me: "We got these fish along with schools of Barilius shacra, B. barna and B. bendelesis and there were a few of the very rare Puntius guganio too. They need well oxygenated and clean waters. It grows to be very large, but is very peaceful by nature." Andrew says he's kept them alongside very delicate fishes without problems.
Water: Not known. Should be OK in water either side of neutral.
Notes: There's some debate over the current genus of the fish. Some believe it is correctly placed in Cyprinion, while others put the fish in Semiplotus (as S. semiplotus). There are five other fish in the Semiplotus genus (and 17 in Cyprinion). Many are rare in the wild, and in the West Bengal area this fish is endangered and is being captive-bred using hormone injections to trigger spawning.
Identification: I managed to confirm the identification of this fish using the key in Day's Fishes of India, which identifies it as a Cyprinion. According to Vishwanath and Kosygin's (2000) guide to the group, this species can be identified from other Indian cyprinids by the following characters: four dorsal spines and four branched rays; 23-25 anal spines and seven branched rays; last simple ray of dorsal unserrated and a tranverse series of open pores running posteriorly from snout to orbit. The underslung mouth and forked caudal fin are also quite distinctive.
Availability: A number of shops imported this very unusual cyprinid species during December. It was first imported a couple of years ago by BAS. We found these on sale in Leicestershire.
Price: Expect to pay about 20 for one of these.