The Paddle-flap scorpionfish, Popeyed Scorpionfish or Eschmeyer’s scorpionfish, Rhinopias eschmeyeri is a very unusual looking fish. They have a very distinctive set of paddles or flaps above the eyes from which they obtain their name.
These can be clearly seen in the image below. The flap is slightly forward of the middle of the eye. They are sometimes confused with the Weedy Scorpionfish which have more frilly appendages but otherwise look similar.
As with all the scorpionfish, they are ambush predators. On the Tanzanian coast they are extremely rare and are not often seen. This is probably a function of their excellent camouflage as well as their rarity.
The body colour varies from brown to a lavender colour with red in between. They have a laterally compressed body with a proportionally large head and a large mouth. There are numerous frills on the body which aid in camouflaging them. They have distinctive paddles or flaps over the eyes. They grow up to 23 cm in length. The spines of the dorsal fin contain toxins which provide them with protection from larger predators.
IN THE WILD
The Paddle-flap scorpionfish is usually found on the reef or on rubble surrounding corals. Despite their sometimes bright coloration they are well camouflaged and can be very difficult to spot. They are fairly rare and are not commonly seen. Being poor swimmers they tend to either make short hops across the bottom or crawl on their pelvic fins rather than swimming.
They will usually wedge themselves into a strategic position using their pelvic fins and sit and wait for their prey. They are most often seen on the periphery of coral bommies with large quantities of cardinalfish and sweepers on them. They will usually be sitting one to two meters from the structure and if one finds one there are likely to be more close by in the same radius. On several occasions we have found four around the same feature. We have also found them in close proximity to the Weedy Scorpionfish. So if you find one, look for more nearby.
Normally they position themselves where there are large concentrations of small fish. Bommies with large concentrations of small fishes such as Sweepers or Cardinalfish are their favorite hunting grounds.
The Paddle-flap scorpionfish are found across the Indo West Pacific oceans, mainly on reefs or rubble at depths below 18 meters.
The Paddle-flap scorpionfish are ambush predators and will eat any passing fish or crustacean that they can fit in their mouths. Having no teeth the prey is swallowed whole and is pulled into the mouth by the suction created when they open their mouths.
Paddle-flap Scorpionfish are oviparous with females producing eggs. When fertilized these are released and float near the surface. Little else is known about Paddleflap scorpionfish reproduction.
Paddle-flap Scorpionfish are kept in aquariums by some specialist aquarists. With their bright colors and unusual looks they can make an attractive addition to a tank. However they will eat anything that fits in their mouths and as a result care has to be taken in choosing their tank mates. Preferably they should be large enough to not fit in their mouths. As with most scorpionfish they are relatively easy to get onto prepared foods.