First record of Lepanthes appendiculata Ames ( Orchidaceae : Pleurothallidinae ) from Nicaragua , with comments on the morphological variation , geographical distribution , and conservation status

Lepanthes appendiculata Ames, a new record for the orchid flora of Nicaragua is presented, with comments on its geographical distribution, floral variations, and analysis of conservation status following IUCN criteria. Additionally, we include iconography of its floral variations, habitats, and a detailed distribution map. Based on the herbarium records and iconography, we also accept and corroborate 10 species of Lepanthes Sw. in Nicaragua.

The genus Lepanthes Sw. (Orchidaceae, Pleurothallidinae) includes more than 800 species, ranging from southern Mexico through Central America and the Antilles to Bolivia and Brazil (Thoerle and Hirtz 2015).Species of Lepanthes are epiphytic or rarely epipetric plants, characterized by the racemose inflorescence and floral characteristics that include usually transversely bilobed petals and usually a tripartite lip with an appendix (Thoerle and Hirtz 2015).
In Nicaragua between nine and 15 species and subspecies of Lepanthes have been reported; however, the exact number depends on which are ones accepted, the correctness of determinations, and whether species are confirmed by the presence of a voucher.Hamer (1983Hamer ( , 1984Hamer ( , 1985) ) recorded eight species and one subspecies, and Ossenbach et al. (2007) recorded 14 species and one subspecies, while van den Berghe and van den Berghe (2008) reported 13 species and one undetermined species.The Flora de Nicaragua (last updated on 3 June 2009) reported 10 species (Tropicos 2015) and CITES (2010) 14 species (Table 1).However, some of the species totals above include synonyms, are based on misidentifications, or they lack authenticated herbarium specimens to scientifically confirm their presence in Nicaragua.In Guatemala, L. appendiculata occurs in the provinces of Alta Verapaz (Cobán; Figure 2A, type specimen), San Juan Chamelco, and San Cristóbal Verapaz (Figure 2B).It is also found in San Pedro (Carcha municipality) and Baja Verapaz (Purulha municipality) (Figure 2B, 2C), as well as in Chiquimula, Huehuetenango, Jalapa, Jutiapa, Progreso and Zacapa.The species grows on the trees of Clethra sp., Liquidambar styraciflua L., Persea donnellsmithii Mez, Magnolia guatemalensis Donn.Sm.and Quer cus sp.It is found in association with other orchids, such as Lepanthes scopula Schltr., L. stenophylla Schltr., L. verapazensis Archila, Lepanthopsis floripecten (Rchb.f.) Ames, Stelis villosa (Knowles & Westc.)Pridgeon & M.W. Chase, and S. guatemalensis Schltr.Lepanthes ap pendiculata occurs in wet forests and subtropical lower montane rainforests between elevations of 1100 and 2500 m.
For example, Lepanthes dis ticha Garay & R.E.Schult., cited as an accepted name in several studies (Table 1), is synonymous with L. pristidis Rchb.f;L. johnsonii Ames, a species restricted to Guatemala and Mexico.The taxon not determined by van den Berghe and van den Berghe (2008) corresponds to L. appendiculata.
During fieldwork (1 August 2015) at the Reserva Natural Cerro El Arenal, Matagalpa state, in northwestern Nicaragua, one of us collected a specimen of L. appendiculata (NCA 6, HULE) which represented the first record of this species in Nicaragua.Biogeographical distribution and eco-vegetation data are based on previous publications (Salazar Chávez and Soto Ar enas 1996; Hamer 1998), herbarium collections, and specimens that we photographed in the field (Appendix 1).With these distribution data, we evaluated the conservation status of L. appendiculata following the criteria of IUCN (2014) and GeoCAT (Bachman et al. 2011).On the other hand, we recognize 10 species based on the drawings and/or photos of references cited in Table 1 and relevant herbarium specimens (Appendix 2).
Lepanthes appendiculata was previously reported from the southwest Mexico to northern Nicaragua, mainly in the province of Chiapas Highlands; and In El Salvador, L. appendiculata has been reported grow ing in rainforests of the Morazán department at an altitude of 1800 m (Hamer 1974).In Honduras, this species is widely distributed in national parks and reserves along the central parts of the Atlántida (Pico Bonito National Park, Texíguat Wildlife Refuge; Figure 2E), Comayagua (Cerro Azul Meámbar National Park; Figure 2F), Francisco Morazán (La Tigra National Park; Figure 2G), Misoco Biological Reserve (Figure 2H), Lempira (Celaque Mountain National Park; Figure 2I), and Olancho (Sierra de Agalta National Park).Elsewhere, it is also known from the departments of Francisco Morazán (El Chile locality; Figure 2J), Intinbucá (San Francisco de Opalaca municipality; Figure 2K), Olancho (Juticalpa, El Armado; Figure 2L), and Santa Bárbara (Santa Bárbara municipality).In these places, it grows on oak trees (Quercus sp.) in cloud forests (between elevations of 1100-2600 m) except in the eastern region of the Honduran Mosquitia.
Our collection is the first report of L. appendiculata from Nicaragua (Figure 3), where it was found in the Jinotega in Cerro Arenal Natural Reserve.There, it occurs along with L. scopula, L. helleri A.D.Hawkes and Lepanthopsis floripecten on the trees of Cupania glabra Sw. in the cloud forests between elevations of 1300-1500 m (Figure 4).
Lepanthes appendiculata is a morphologically variable species (Figures 2 and 3).The vegetative variation mainly involves the color (completely green [Figure 2B, 2F-2L] to green with reddish or purple spots [Figure 2D]) and leaf shape (cordate, obovate to ovate, ovatelanceolate).However, this variation apparently is not correlated with a geographical distribution pattern.Florally, the variation resides in the color of the petals, from rose with a red inner base (RRIB) (Figure 2C, 2D) or yellow with red inner base (YRIB) (Figure 2E-2L) to yellow-orange with red inner base (YORIB) (Figure 3).In Mexico, the reported populations of this species are RRIB (Salazar Chávez and Soto Arenas 1996), while in Guatemala, populations are either RRIB (as in the holotype) or YRIB but together within the same population.In several populations in Honduras, individuals are exclusively YRIB, as in Guatemalan populations.In the single known population in Nicaragua (Jinotega), petals are particularly striking for the YORIB, but the shape, size and color of the other segments of the flower are similar to populations of Guatemala and Honduras.
According to IUCN (2014) criteria and the Geospatial Conservation Assessment Tool "GeoCAT" (Bachman et al. 2011), L. appendiculata should be considered a Least Concern species because it is distributed over a large range (extent of occurrence: 163,599.9km 2 ).However, the area of occupancy using a 2 × 2-km cell grid is only 100 km 2 (cell width of 2 km), which suggests that Endangered may be appropriate for this species.Lepanthes appendiculata does have a large area of distribution from southwest Mexico to northern Nicaragua, usually growing as an epiphyte on the thick branches of high trees in lower montane subtropical rainforests, high evergreen forests, pine-oak-Liquidambar forests, and in cloud forests.However, in Mexico, Salazar Chávez and Soto Arenas (1996) gave the low number of plants and habitat destruction are the primary risk factors.In Guatemala, the wet forest and subtropical lower rainforest habitats where it commonly grows and are seriously threatened due to extensive conversion to agriculture (cultivation of corn, beans, tomatoes, potatoes, and chili).Other factors impacting the survival of this species are uncontrolled wildfires, incentives by the local forest department to replace native vegetation with Pinus maximinoi H.E.Moore, and rapid changes in land use due to extensive cattle ranching in the areas adjacent to the Guatemalan forests.In Honduras, protected populations are only within national parks and reserves, but outside of these areas other populations are unprotected and habitats are severely jeopardized by unmonitored wildfires and agricultural activities.In Nicaragua, L. appendiculata habitat overlaps with the local, highly lucrative coffee plantations.Coffee is the principal cash crop but other crops include hillside cabbage, lettuce and beans.Conversion of native habitat to these crops are impacting L. appendiculata.This species and other local orchids that grow on the stems and branches of the coffee plant or other trees are indiscriminately removed by scraping because coffee growers believe that orchids are parasitic and their elimination will boost coffee production.In light of these threats, we believe that L. appendiculata should be categorized as Endangered rather than Least Concern.
Cash-Arcia et al. | First record of Lepanthes appendiculata from Nicaragua between the lower reaches of Veracruzan, Pacific Lowlands and Mosquito provinces (Figure 1).In Mexico, it occurs in the Oaxaca and Chiapas states where it is an epiphyte with L. breedlovei Salazar & Soto Arenas in high evergreen and pine-oak-Liquidambar forests at elevations of 1350-2500 m (Salazar Chávez and Soto Arenas 1996).

Figure 4 .
Figure 4. Habitats of Lepanthes appendiculata.A-B: Cloud forest in Guatemala; C-D: Cloud forest in Nicaragua; E-F: Subtropical lower montane rainforests in Guatemala.Photos by E. Mo (A-B, E-F) and N. Cash-Arcía (C-D).