Bulbophyllum molossus, an epiphytic or lithophytic orchid, rather common, is native to Madagascar and Réunion.

In Madagascar, the species is distributed in nine regions, whereas in Réunion, it is known from 70 human observations in 10 communes and the national status is Vulnerable [VU C2a(i)] according to the Inventaire National du Patrimoine Naturel (INPN). The species occurs in humid and subhumid evergreen forests, on rocky, wet areas, often on fallen tree beside river, at elevations of 400–1,700 m. It is known from 102 collections made between 1925 (Perrier de la Bâthie 17119) and 2021 (Antananarivo Spirit Collection 789T994). Six Spirit collections without accurate locality data are not taken into account for this assessment. The remaining 96 collections represent 62 occurrences among which 20 were made within the footprint of a mining project that has undergone and is undergoing intense human pressure from forest clearing, and should be considered as extirpated. Seven collections (Hermans 5194; Humbert 23379; Perrier de la Bâthie 18460; Sieder O00B74_1, O00B170_1, O00B219_1, O00B571_1) representing four occurrences, have been recorded in unprotected forests and should likewise be considered as extirpated or as likely to be extirpated in the near future due to forest degradation from small scale logging, wood harvesting for subsistence, wildfires, and slash-and-burn agriculture (tavy). Two occurrences (Antilahimena 6771, Rakotondrajaona 676) recorded near the limits between the footprint and the Conservation Zone, were facing the indirect impact of the mining project and should be considered as extirpated. Three collections (three occurrences) of the species have been made in the Conservation Zone surrounding the footprint of a mining project undergoing intense human pressure such as forest clearing, which should be subjected to protection in the near future. Thirty-seven collections representing 29 occurrences, have been made in 13 protected areas of Madagascar. One occurrence (Kiehn 158) has been recorded in the Departmental forest of Volcan Sud in Réunion. Three collections representing three occurrences have been recorded in the Analamay-Mantadia Forest Corridor (CFAM) which should be protected in the near future. Other three collections (Andrianjafy 737, Fischer 4401, Rabarimanarivo 665) representing three occurrences of this species, have also been made in unprotected areas and are facing habitat degradation due to slash-and-burn agriculture (tavy) along with wood harvesting for subsistence and wildfires. The species is thus known from 96 collections representing 36 existing and 26 extirpated occurrences.

The extent of occurrence (EOO) of the species is estimated as 584,087 km² (far exceeding the upper limit for vulnerable status under criterion B1) whereas its area of occupancy (AOO) is estimated at 144 km² (falling within the limits for Endangered status under criterion B2). With respect to the most serious plausible threat of forest clearing due to mining activities, the 36 existing occurrences represent a total of 25 locations (sensu IUCN 2022), far exceeding the threshold for threatened category under criterion B. It is inferred that the loss of occurrences from mining activities, wood harvesting for subsistence, wildfires and slash-and-burn agriculture (tavy) has induced or will induce a continuing decline in EOO, AOO, the habitat quality, the number of subpopulations, and the number of mature individuals. Otherwise, the species has ornamental value and has been collected at the Antananarivo flower market. The 26 extirpated occurrences represent an inferred population reduction of 24%, based on a reduction of the AOO, using a 2 × 2 km cell size, from 188 km² in 2005 to 144 km² in 2035, which does not correspond to any threatened category under criterion A. Therefore, B. molossus is assigned a Least Concern (LC) status.

Bulbophyllum molossus is native to Madagascar and Réunion. In Madagascar, it is known from nine Regions: Alaotra-Mangoro, Analanjirofo, and Atsinanana in the formerly recognized Province of Toamasina; Amoron'i Mania, Ihorombe and Vatovavy in the formerly recognized Province of Fianarantsoa; Analamanga in the formerly recognized Province of Antananarivo; and Diana and Sava in the formerly recognized Province of Antsiranana (Madagascar Catalogue 2022). In Réunion, the species is known from 70 human observations in 10 communes according to the Inventaire National du Patrimoine Naturel (INPN 2022).

The population of Bulbophyllum molossus is currently thought to be decreasing since its habitat is threatened by forest degradation due to selective logging, wood collection for small-scale subsistence and slash-and-burn agricultural practices (tavy), and by forest destruction due to mining activities. The number of mature individuals of the species is not known and cannot be estimated since the species is an epiphytic plant on the trunk of trees or on rocky substrate. The species is reported to be rather common (Bosser and Lecoufle 2011).

Bulbophyllum molossus is an epiphytic or lithophytic orchid growing in humid and subhumid evergreen forests at elevations of 400–1,700 m. It is reported to be on rocky, wet areas, often on fallen tree beside river. At the mining site, it was collected on the crust (Razanatsoa 149), as well as out of the crust (Antilahimena 5318). It has been recorded flowering from October to March and fructifying from February to June (Madagascar Catalogue 2022).

This species experiences a continuing decline in EOO, AOO, habitat quality, number of subpopulations and number of mature individuals due to mining activities, wildfires, wood harvesting for subsistence, and slash-and-burn agriculture (tavy).

Bulbophyllum molossus is reported to be collected at the Antananarivo flower market (Fischer 1460 and 1465).

In Madagascar, 37 collections representing 29 occurrences, have been made in 13 protected areas, the Ambositra Vondrozo forest corridor Protected Harmonious Landscape (two occurrences), the Analamazaotra National Park (three occurrences), the Anjanaharibe-Sud Special Reserve (one occurrence), the Anjozorobe-Angavo complex Protected Harmonious Landscape (one occurrence), the Ankeniheny-Zahamena forest corricor (Ankerana - Main parcel - Vohibe Forest) Natural Resources Reserve (nine occurrences), the Makira Natural Park (two occurrences), the Mangabe-Ranomena-Sahasarotra Natural Resources Reserve (one occurrence), the Manongarivo Special Reserve (one occurrence), the Marojejy National Park (two occurrences), the Maromizaha Natural Resources Reserve (one occurrence), the Montagne d'Ambre National Park (two occurrences), the Ranomafana National Park (two occurrences), and the Torotorofotsy Protected Area (two occurrences). In Réunion, the species is known to occur at Forêt départemento-domaniale du Volcan Sud (one occurrence). Three collections (three occurrences) have been made in the Conservation Zone surrounding the footprint of a mining project undergoing intense human pressure such as forest clearing. This Zone should be protected in the near future. Three collections (three occurrences) of this species have also been made in the Analamay-Mantadia Forest Corridor (CFAM) which should be protected in the near future. The species is listed in Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). It has been brought to cultivation at the Ambalabe, Ambatovy, Antananarivo, and Tsimbazaza shade houses. Seeds are currently banked at both Ambatovy and Antananarivo Seed Banks. Micro-propagation must be developed for the species. Further awareness building is recommended for local communities and national authorities.