Matt Clarke on an unusual toadfish for the marine fish-only aquarium.
Common name: Gulf (or Orange) toadfish
Scientific name:Opsanus beta
Size: Up to 30cm/12".
Origin: This West Atlantic batrachoidid species is found in Florida, the Bahamas and the Gulf of Mexico, down as far as Mexico.
Habitat: Beds of seagrass and among rocks in bays and lagoons.
Breeding: Rarely kept in the aquarium, so not known to have bred in captivity. Wild fish spawn between February and March. Interestingly, they produce several different nest types. Males tend to prefer to inhabit nests that are in close proximity to those of other males, but can be territorial with their neighbours.
Aquarium: This is a fairly inactive species and spends much of its time hiding among rocks. As such, although a fairly large aquarium is important, tank size is not as critical as it is for some more active-swimming fishes. A tank of at least 120cm/4' would be a good starting point. Only mix this species with larger fishes - it could have the capacity to swallow small tankmates. Ensure that the tank is well filtered. Can be aggressive.
Diet: Meaty foods, such as pieces of whole fish and shrimp.
Notes: Opsanus beta is used as a model organism for research on ureotely, something which occurs only in a handful of fishes, such as the Batrachoididae. This species can swap from excreting ammonia to synthesising and excreting urea.
Availability: These aren't common in the trade. We recently spotted several at The Aquarium in Lincolnshire.
Price: These were on sale for 29.95.