Small insects more commonly known as
fruit flies.
The word is from the dutch word 'Biervliegje' wich is commonly used by the dutch to describe the insects who
have a taste for alcoholic beverages,especially
fruit flies.
Fruit flies have a taste for rotting fruit and in nature the smell of alcohol is like hitting the jackpot for creatures who live of rotting fruits.
The beerfly is any flying insect that can and will land in your fresh pint.
But most of all they will do it
over and over again if given the chance!