Light-harvesting photosynthetic tetrapyrrole chromophore-protein from the phycobiliprotein complex. Heterotetramer of 2 different alpha chains and 2 identical beta chains which form 2 alpha-beta heterodimers within the heterotetramer. Contains two phycocyanobilin chromophores, one mesobiliverdin chromophore and one 15,16-dihydrobiliverdin chromophore with binding mediated by both the alpha and beta subunits. The light-harvesting system in Cryptophytes contains phycobiliprotein complexes. Unusually they are composed of either phycoerythrin (CPE) or phycocyanin (CPC) but never allophycocyanin (APC), with only one type of biliprotein being present in any one species. Unlike cyanobacteria or red algae these proteins are not arranged into higher-order phycobilisome complexes, and they are found in the thylakoid lumen. Belongs to the phycobiliprotein family.