My ichthyology is very poor (nearly as poor as the labelling in the otherwise excellent Afrykarium!). Any help identifying these various fish pictures would be very much appreciated (and my apologies - I am sure they are fairly common species which I probably *should* be able to identify myself).
Thanks sooty. If that's the case I'd be interested to know how it's easiest to distinguish between the two species? A google image search for 'unicornfish' or 'Naso unicornfish' pulls up several photos labelled as N. brevirostris which look very similar to N. unicornis, but photos used on zootierliste and websites with some authority look quite different.
I'm still drawn to thinking this is N. unicornis, unless there's a lot that I'm missing.
have you got a photo showing the tail? N. unicornis has two blue spines on the caudal peduncle (hence "blue-spined unicornfish) which brevirostris does not.
I'm fairly certain this is N.unicornis as brevisrostris has a longer body, different shaped head and operculum, and usually has either lines or spots on the body (in Australia it's commonly called the Spotted Unicornfish).