It's a Pearly Parakeet (or conure, if you prefer). Same genus as the Green-cheeked. Quite remarkable how rare these apparently are in zoos (based on zootierliste). They're reasonably widespread in private aviculture and their rarity in the wild means that a zoo breeding project could be started. The problem might be getting pure stock, especially now where it has been proposed that eastern norminate (coerulescens is a synonym) and western anerythra are separate species.
If it is pure (more on that below), it is definitely a nominate lepida. This is the one you usually see, although sometimes labelled with the synonym coerulescens (which actually may be the species' valid name instead of lepida, but that's another discussion!). The red to the wings isn't always obvious and depends on how the wings are held, but the reddish to the belly of anerythra is hard to miss and would've been obvious on a photo like this. In fact, I don't remember ever seeing a definite anerythra in captivity and it is entirely possible nominate lepida is the only one in European and North American aviculture (careful: juvenile lepida and juvenile crimson-bellied can have belly markings that resemble anerythra's). However, the problem with many of these Pyrrhura is that they can hybridize with close relatives. For example, under captive conditions, pearly easily hybridize with crimson-bellied. Many of these Pyrrhura were fairly rare in aviculture in earlier decades and knowledge of their differences was also quite limited: I know of cases where they were mixed and if it was a few generations back it isn't necessarily obvious today. For example, you sometimes see people claiming to have either of the two subspecies of sulphur-winged. The problem is that some breeders deliberately bred out certain markings to make theirs look closer to one of the subspecies and then basically assumed that they now had that subspecies. That obviously isn't how taxonomy work!
The entire taxonomic review of the pearly is available here, but only the résumé is in English (remaining in Portuguese).
