Matt Clarke looks at a new import for the UK, the Paradise threadfin, Polynemus paradiseus.
Common name: Paradise threadfin
Scientific name: Polynemus paradiseus
Size: About 25cm/10".
Origin: Estuarine waters from Sri Lanka, India and Pakistan. These were imported from Thailand.
Water: This is a euryhaline species and enters freshwater. Those featured here were packed in freshwater and are kept in hard, alkaline freshwater.
Aquarium: A spacious aquarium is a must, over 120cm/4', as well as wide and deep. They have very long appendages and use them to feel their surroundings. They are said to be quite sensitive to poor water quality and extremely difficult to ship. This is a species only for expert fishkeepers.
Diet: Wild fish eat small shrimps and fishes. Captive specimens are tricky to feed initially. These needed live
daphnia and brineshrimp to start, but now take frozen foods. They become hyperactive when food is added.
Habitat: Sandy estuaries.
Availability: We found these at Wildwoods in Crews Hill, Middlesex.
Notes: A member of the Polynemidae family which includes 33 predominantly marine and brackish water species in seven genera. Several look very similar to paradiseus and are difficult to identify. Contrary to some talk in the trade, these are not catfishes.
Rarity rating: As rare as rocking horse droppings - this is the first one we've ever seen!
Price: £59.95 for a 13-15cm/5-6" fish.