Reforestation is expanding rapidly worldwide; however, most reforestations lack the heterogeneous structure of mature forests, limiting their capacity to support biodiversity. We evaluated whether Mediterranean reforestations could recover the diversity and composition of epiphytic lichen and bryophyte communities found in well-conserved mature forests and identified the key structural and environmental drivers underlying these patterns. Epiphytic diversity and composition were assessed across 14 mature and 14 reforested pine stands (Pinus nigra and P. sylvestris) in central Spain spanning a wide range of forest ages and structures. Forest type was the dominant determinant of both diversity and composition, and the Forest Maturity Index (FMI), a composite maturity metric developed to integrate key structural attributes associated with late-successional conditions, emerged as the most influential structural predictor. Tree age showed weak effects largely confounded with FMI, being independently significant only for bryophyte richness. Although structural predictors affected epiphytic diversity in a similar way across both forest types, reforestations did not reach the levels of structural maturity needed to support late-successional or specialist epiphytic communities. Indicator species analysis further revealed that all late-successional and specialist taxa were restricted to mature forests. Our findings highlight the irreplaceable role of mature pine forests for epiphytic conservation and emphasize the importance of restoration approaches that facilitate the development of mature-forest structural attributes. Keywords: Mediterranean ecosystems; Forest maturity index; Lichens; Bryophytes; Biodiversity recovery; Reforestation effectiveness.