Anathallis tigridens

Epiphytes have experienced dramatic population decreases mainly because of habitat loss and extraction activities, which have driven many species close to extinction (Mondragon et al. 2006). Since the 16th century the Atlantic rainforest, a biodiversity hotspot (Myers et al. 2000), has suffered from uninterrupted deforestation and has been reduced to 8% of its original area. Remains are mostly dissected in tiny and widely separated forest fragments. The forests of coastal Bahia are considered among the more endangered habitats on Earth because they have been reduced by 95%, while the Serra do Mar coastal forests have been reduced by at least 50%. At present, forest conversion into pasture is occurring at alarming rates stimulated by the economic crash of cocoa plantations. Other threats to epiphytic orchids in the region include urban development, tourism, the harvesting of firewood, illegal logging, plant collecting, and invasion by alien species, air pollution from adjacent factories and residential and fires. Forest fragmentation directly threatens epiphytic orchids through the loss of habitat, pollinators, increased desiccation and risks of fires, invasion of ruderal plants and also facilitates extractivism of ornamental species (Da Silva 2001, Silva Matos et al. 2002, Filho and Leme 2006). The ability of the taxon to regenerate and persist in disturbed and secondary forests is unknown. This orchid has very attractive flowers and, although it does not appear to be commercially available, it is cultivated by orchids enthusiasts and may be the subject of unscrupulous collection. Collecting from natural sources is still very common in Brazil in spite of prohibitions of international commerce of species collected in the wild (Appendix II of the Convention on International Trade in Endangered Species – CITES) (Saddi et al. 2005).

This species was collected within the Tijuca National Park, in Rio de Janeiro and the Reserva Biologica A. Ruschi, in Espirito Santo, both ca 3,000 ha in areas. The type was collected in 1916. The Tijuca National Park, the largest area of Urban forest in the world, was created in 1961 and forests were mainly replanted. Current occurrence of the taxon in this conservation unit is unknown. No specific conservation measures seem to be in place for this species however. Conservation efforts have been so far only limited in the region. The forest code needs to be better enforced (Tabarelli et al. 2005). Biodiversity corridors are currently being implemented as part of the PP-G7 Atlantic forest subprogram (Tabarelli et al. 2005) and the Unesco Biosphere Reserve of Mata Atlantica development. Many forest fragments occur on private land and innovative incentives are needed. Extensive habitat restoration and expansion of protected areas is needed for the establishment of corridors (Filho and Leme 2006). This orchid is currently listed on Appendix II of the Convention on International Trade in Endangered Species (CITES). The taxon is grown ex situ in botanical institutions. Seventy-seven percent of all species of the tribe Pleurothallids are known from three or fewer sites (Koopowitz et al. 1993). Surveys and census should be conducted in both sites of collection and surrounding fragments of montane Atlantic forests to determine the current size and range of the population. The population should be closely monitored and its dynamics studied. A species recovery action plan needs to be designed for this species. Micropropagation protocols should be designed for population reinforcement, for in vitro preservation and to alleviate the potential pressure of extraction on the wild population. Raising awareness on the risk of extinction face by these epiphytic orchids is important. Seeds should be collected for germplasm conservation.