Check out this charming video of a minute goby hitching a lift on the back of a nudibranch.
The footage, uploaded onto Vimeo by liquidguru, features a Bullocks nudibranch (Hypselodoris bullockii), which reaches a size of just 4-7cm, giving an idea of how tiny this goby must be.
Bullock's Hypselodoris with Goby from liquidguru on Vimeo.
Why not take out a subscription to Practical Fishkeeping magazine? See our latest subscription offer.