If I want to fill in a blackhead blenny on the fish ID form it's impossible? But is this a blackhead blenny (Emblemariopsis bahamensis)?
I think it's a redspine blenny
I don't see short cirrus over each eye in the photo. If there aren't any, then it's not a redspine. It could be a blackhead or even a glass, but I can't say for sure. Perhaps someone else can see enough detail to make a definitive call. Sorry. It's a pretty good photo though.
AAT Member (TWA) - REEF Member Since 1998
As Diver Dave correctly points out, without an orbital cirrus it can't be a spikefin. The overhead angle obscures whether or not there is a "spike" at the front of the dorsal fin. If there is a spike then it's a glass blenny. If there isn't a spike, it's either a shorthead, seafan, or blackhead (all in the genus Emblemariopsis). Distinguishing between the latter three in the field is extremely difficult.
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