I don't have it, but here's a suggestion: How about Gargolye model tinted black?
That looks like a Bat a lot (unless you want the 'fat Bat' type like the Batrider's)
Most likely no such thing ... but you could try some kind of Wyvern change, or the Undead Gargoyle and make it smaller? .. or change the player colors of the Gargoyle, so that it's full grey? (if you want to make a bat-looking mob of course)
Ghan has said he has fixed this. Monovertex please confirm this fix. This was only a problem with people that had signatures in the upper levels like not the special members but the respected members.