Auguste Glaziou went to Brazil in 1858 at the invitation of Emperor D. Pedro II where he worked as director of the Imperial House of Parks and Gardens in the city of Rio de Janeiro until 1897. He is considered one of the greatest plant collectors of Brazil and collected numerous bryophytes. The bryoflora of the state of Rio de Janeiro is one of the richest in the country, but also includes the highest number of threatened species. Glaziou collected in Rio de Janeiro where the coverage of the Atlantic Forest suffered a great reduction and loss of biodiversity. The objectives of this work are to analyze the species registered by Glaziou, assess what percentage of the bryoflora was sampled at that time, re-collect and evaluate the conservation status of the species. Our results show that 86% of the species collected by Glaziou have been collected in the state Rio de Janeiro. 4% percent have been collected in the last 60 years, 10% has not been found in the last 100 years and two species remain only known from the original Glaziou collection (= type). Our fieldwork recorded 35% of the species in their original sites. Eighteen species are considered threatened taxa in the state of Rio de Janeiro, including 16 species that are critically threatened (CR), two threatened (EN), three of little concern (LC) and one of insufficient data (DD).