The length of the forewings is 4–5 mm.Differs from Caryocolum proxima as follows: forewings somewhat narrower, a distinctly marked black dot in disc before costal bar, posterior fascia not angulated, forming two direct opposite spots. Larva pale yellowish; head black; 2 red-brown, plate black.[2][3][4][5]
Adults have been recorded on wing from late June to late September.[6]
^Meyrick, E., 1895 A Handbook of British Lepidoptera MacMillan, London pdf This article incorporates text from this source, which is in the public domain. Keys and description
^Langmaid, J. R., Palmer, S. M. & Young, M. R. [eds]. 2018 A Field Guide to the Smaller Moths of Great Britain and Ireland [3rd ed.]Reading, Berkshire. British Entomological and Natural History Society