However, I've never found any evidence that they are black nightshade, other than a similar appearance. Chichiquelite is also similar to black nightshade (but it's another species, too). Otricoli Orange Berry is black nightshade (but it's an orange kind of it). Wonderberries are listed as a separate species (and I think they're a hybrid species). I've grown all three. Wonderberries slip more easily from their calyxes, and in my opinion taste better. The others tasted toxic to me, however; see these posts I made about them:
* http://vegetables.boards.net/thread/136/ripe-chichiquelite * http://vegetables.boards.net/thread/135/ripe-otricoli-orange-berries
Whatever the case, having eaten wonderberries, I can say with confidence that they the ripe ones are quite edible.
Also note that people in that thread say wonderberry leaves are edible. Huh? From what I've read elsewhere you definitely don't want to eat them for food. I wouldn't eat them, even though some people eat the leaves of edible black nightshades. They're a different species.
Wonderberry = Solanum retroflexum
Black Nightshade and Otricoli Orange Berry = Solanum nigrum
Chichiquelite and Garden Huckleberry = Solanum melanocerasum
Nevertheless some people think they're the same still. I doubt it, however.
Wonderberries are the easiest of those species to grow in my garden by far.
Note that my wonderberries are never particularly shiny pre-harvest. Chichiquelite is shiny, though.
Location: SW Idaho, USA
USDA hardiness zone: 6
Elevation: 2,260 feet Profile post