Red currants (literally 'Frankish grapes'). Black ones, which grow in northern Europe, are rare and known as είδος θάμνου όμοιο με φραγκοσταφυλιά ('a shrub similar to the red currant').
Not of course to be confused with the original 'currants', which are really grapes, mávri stafídes.
Image by Davide Restivo