After the sermon by Revvy I hardly feel this is necessary, but you're missing out on the big pink elephant sitting in front of you on this one. IPA was originally brewed to survive for months upon months on ships with no temperature controls and not even an idea that germs existed. Besides, some people pay good money to get sick from mold (fungi).
I'm not missing any elephant, I'm just pointing some info out to the uber noob brewers who are deathly afraid of their beers being toxic...it is something than many of us strive to do, whenever some new brewer jumps in, or is worried about it, we try to correct that piece of mis-information.....that is all....
And as many of us have said, more than likely the beer is fine, below the surface of the mold.......
You are right about the IPA's being meant to be hardy beers.
But no one truly knows whether or not any of the casks of IPA's didn't necesarrily have a thin pellicule of mold or something on the surface of them and were still consumed, quite simply, because they often were transported in casks, where it wasn't quite that easy to see what was floating on the top whilst the beer was being served, usually out of a spigot via gravity.....
AND don't forget those wooden casks were crawling with all manner of critters, like Brett, Aecetobactor, and lactobasillus...so honestly, the IPA that reavelled across the sea, may not have tasted anything like when it left the brewery...OR like our modern IPA's in sanitized bottles...
Pellicules and layers are usually formnd to PROTECT the contents below...so those Ipay may have indeed had that kinda skin on it for all we know.
They were made not necessarily to sour, or go stale, but that doesn't mean that they were bulletproof. They were more than likely different than they were at the beginning of the voyage.....
Oh, and I'm the one on here who usually points out that beer was brewed before germ theory...and that if beer had turned out bad, or toxic, would have gone the way of the dodo bird, new coke, or evil's formerly favorite beverage, pepsi clear.
But you are right they were pretty hardy beers....
Oh, OP...I have racked under mold and have had the beer turn out fine...not the best beer. But it didn't kill anyone. Of course my mold wasn't so "colorful."