An assessment of the conservation status of Restrepia (Orchidaceae) reveals the threatened status of the genus

Abstract

Introduction35 Restrepia is a small orchid genus comprising 61 species (WCSP 2018) belonging to the 36 Pleurothallidinae, the largest sub-tribe in the Orchidaceae. These species are found throughout 37 Central America and in Venezuela, Colombia, Ecuador, Peru and Bolivia in South America, 38 growing at elevations between 1000 -3000 m a.s.l. in areas of montane rain forest. These forests 39 were identified as deforestation 'hotspots' by Mittermeier et al. (1999). Habitat loss and orchid 40 population decline in these regions has been ongoing (Mittermeier et al. 1999; Myers et al. 2000; 41 Brooks et al. 2002;Bubb et al. 2004;Millner 2013) and from this, it is reasonable to assume that 42 all epiphytic species, including Restrepia, face significant threats to their populations. However, 43 to date, the majority of Restrepia species have not been evaluated against Red List Criteria to 44 determine their degree of threat. Therefore, this study was designed to use information and data 45 currently available online to determine the degree of threat facing this genus and to establish their 46 Red List status, for later inclusion in the IUCN online data base.47 Figure 1 near here 48 The only comprehensive review of the genus is the monograph by Luer (1996a), which does not 49 include the most recently described species. The type species for the genus, Restrepia antennifera 50 (Humboldt et al. 1816) was described in 1801 (Figure 1). Together with other early discoveries, 51 such as R. contorta, R. brachypus and R. guttulata it is widely distributed geographically and 52 exhibits a high degree of within-species variation. The majority of Restrepia species have been 53 identified after 1980 and many of which have only been identified from one or two locations 54 (Luer 1996a). While these may persist in other localities in the wild, they have a narrower 55 geographical distribution compared to those discovered earlier. Species discovered since 1996

An investigation of self‐incompatibility within the genus Restrepia

“…Self‐incompatibility and myophily are regarded as biological synapomorphies within the Pleurothallidinae (Barbosa et al, 2009). Consequently, the genus Restrepia is also thought to be myophilous (Pridgeon and Stern, 1983; Luer, 1996a; Millner, 2013), but this has yet to be confirmed in the wild. The morphology of both R. aberrans and R. chocoënsis differ sufficiently (Luer, 1996a) from other species in the genus that they may comprise two monotypic subgenera, Echmeles and Pachymeles , respectively (Luer, 1996a).…”

“…The majority of Restrepia species are narrow endemics, with poorly researched distributions represented by few herbarium records (Millner, 2013). Preliminary research (H. J. Millner, unpublished data) has shown that with the exceptions of R. trichoglossa (Romand‐Monnier, 2013) and R. contorta (Millner, 2013), all species in the genus should have a minimum global classification of threat as vulnerable, with species found as narrow endemics in threatened locations classified as critically endangered.…”

“…The majority of Restrepia species are narrow endemics, with poorly researched distributions represented by few herbarium records (Millner, 2013). Preliminary research (H. J. Millner, unpublished data) has shown that with the exceptions of R. trichoglossa (Romand‐Monnier, 2013) and R. contorta (Millner, 2013), all species in the genus should have a minimum global classification of threat as vulnerable, with species found as narrow endemics in threatened locations classified as critically endangered. While some species are listed as vulnerable in the Red Book of their countries, e.g., R. aristulifera and R. pelyx in Colombia (Calderón‐Sáenz, 2007), no species are currently listed as vulnerable in the global IUCN Red List (IUCN, 2014), which has led to an underestimation of the threat to the genus (Millner, 2013).…”

Root-Associated Endophytic and Mycorrhizal Fungi from the Epiphytic Orchid Maxillaria acuminata in a Tropical Montane Forest in Southern Ecuador

“…Orchidaceae is considered one of the largest families of vascular plants and is found in almost every ecosystem worldwide [10]. Although a great number of orchid species are found in Ecuador, their survival is endangered due to climate change but also because of anthropic disturbances [11] such as habitat loss due to deforestation, soil erosion, and Diversity 2022, 14, 478 2 of 10 illegal commerce [12]. Even though they produce several thousand seeds in one pod, they are small and lack a nutrient supply for germination [6].…”