68. The Topknot – Wildlife of the Solway
The Topknot – Wildlife of the Solway
This is a rarely seen fish even though it is distributed widely around Britain, mainly because it lives on rocky ground and is not a commercially targeted species.
It is described as a left sided flatfish as its right eye has migrated around the head when it is very small to face upward, this allows us to distinguish it from the only other similar looking fish the Lemon Sole which is a right handed flatfish.
They can grow up to a maximum of 25cm and have a marbled brown and white colouration with a dark bar that runs across the eyes. Other flatfish species can quite rapidly change colour to blend in with the bottom substrate, but the topknot relies on total immobility to avoid being seen by predators or prey.
We love having this quirky fish in our aquarium, but many visitors fail to see it in the display because it has the unusual habit of settling down on vertical rock surfaces or even underneath overhangs, so they think at first glance the tank is empty!
The topknot achieves this gravity defying feat because fins spreading all around its body allow it to create strong suction against smooth surfaces. It’s eyes can be seen swivelling independently as it’s unsuspecting prey such as small fish or crustaceans approach. A rapid pounce to grab its meal and it immediately returns to its favourite spot.