This is a local name for the honey bee sub-species Apis mellifera mellifera (Amm) that is native to the British Isles.
There are about 28 different sub-species of the western honey bee, Apis mellifera, originally distributed through Europe, the Near East and Africa. In the British Isles and Northern Europe, from France to the Urals, the native sub-species is commonly known as the Dark European honey bee or Apis mellifera mellifera (The first two latin names denote the genus and the species, and the third name denotes the sub-species).
Common names for the Dark European Bee include ‘Old English’, ’British Black Bee’, ‘Irish Black Bee’ and ‘Brown Bee’.
see https://bibba.com/honeybee-origins/