Lycianthes hygrophila Bitter

MONRO, A. K., SANTAMARÍA-AGUILAR, D., GONZÁLEZ, F., CHACÓN, O., SOLANO, D., RODRÍGUEZ, A., ZAMORA, N., FEDELE, E. & CORREA, M., 2017, A first checklist to the vascular plants of La Amistad International Park (PILA), Costa Rica-Panama, Phytotaxa 322 (1), pp. 448-450 : 448-450

Lycianthes hygrophila Bitter ( Solanaceae )

Macrocarpaea browallioides (Ewan) A.Robyns. & S.Nilsson ( Gentianaceae ) Maxillaria synsepalum J.T.Atwood ( Orchidaceae )

Maxillaria tricarinatum J.T.Atwood ( Orchidaceae )

Miconia kappellei Almeda & Kriebel ( Melastomataceae )

Monochaetum amistadense Almeda ( Melastomataceae )

Monochaetum vestitum Almeda, Al.Rodr. & Garita ( Melastomataceae ) Monstera cotobrusense Croat ( Araceae )

Pilea matama A.K.Monro ( Urticaceae )

Pterichis herrerae Kolan. ( Orchidaceae )

Schistocarpha croatii H.Rob. ( Asteraceae )

Schultesianthus crosbyanus (D’Arcy) S.Knapp ( Solanaceae )

Scutellaria talamancana A. Pool ( Lamiaceae )

Siphocampylus maxonis E.Wimm. ( Campanulaceae )

Sloanea herrerae Aguilar & D.Santam. (Eleocarpaceae))

Sphaeradenia rostellata R.Erikss. ( Cyclanthaceae )

Stachys riparia A.Pool ( Lamiaceae )

Stelis montana L.O.Williams ( Orchidaceae )

Talamancaster minuscula (Cuatrec.) Pruski ( Asteraceae )

Ternstroemia amistadensis Q.Jiménez & D.Santam. ( Pentaphylacaceae ) Thelypteris chiriquiana A.R.Sm. ( Aspleniaceae )

Tournefortia longipedicellata J.S.Mill. ( Boraginaceae )

Trichomanes consanguineum C.V.Morton ( Hymenophyllaceae )

Trichopilia olmosii Dressler ( Orchidaceae )

Vaccinium bocatorense Wilbur ( Ericaceae )

Vriesea woodsoniana (L.B.Sm.) J.R.Grant ( Bromeliaceae )

PILA includes 73 species that are endemic to the park, 195 species that are endemic to Costa Rica, 85 species that are endemic to Panama and 611 species that are restricted to Costa Rica and Panama.

Exploration of PILA

We recognise 19,466 species records for PILA, 1,219 of which consist of field observations and 18,247 of herbarium collections. Figure 2 plots collection localities on a map of PILA and can be used to assess sampling effort across PILA. It indicates that the Pacific drainage of PILA is better sampled than the Atlantic drainage and that the Costa Rican component of the park has been more intensively sampled than the Panamanian sector. No observations exist for the river basins of La Matina and Vólcan. Of the remaining river basins for which observations do exist the least sampled river basins are Changuinola ( Panama, Atlantic), Culubre ( Panama, Atlantic), Teribe ( Panama and Costa Rica, Atlantic) and Chiriquí Viejo ( Panama, Pacific). The most sampled river basins being Coto Brus-Cabagra ( Costa Rica, Pacific), Coén ( Costa Rica, Atlantic) and Urén ( Panama, Atlantic).

DISCUSSION

Species Diversity

Three thousand and fifty-nine species are recorded for PILA, an area of 4,010 km 2. This figure equates to ca 1% of the vascular plant diversity of the World ( Raven et al. 2005, IUCN 2006, Christenhusz & Byng 2016), 17% of the diversity of vascular plants in Central America ( Davidse et al. 1994). To put these figures into context, PILA represents ca 1.7% (Food and Agriculture Organization 1993, Harcourt & Sayer 1996) of the remaining forest of Mesoamerica, a recognized biodiversity hotspot ( Toledo et al. 1997) yet contains 17% of its vascular plants. With respect to the two host countries of the park, PILA’s national components represents 8% of Costa Rica remaining forest cover ( Fondo Nacional de Financiamiento Forestal 2007) and 6% of Panama’s remaining forest cover ( Correa et al. 2004) and ca 30% of their species (9,520 spp., Correa et al. 2004; 9,361 spp., Hammel et al. 2004).

Of the 3,046 vascular plant species recorded for PILA, 436 (14%) are ferns and Elaphoglossum , Asplenium , Diplazium and Hymenophyllum rank among the most species-rich genera in the park ( Table 3). In fact, Elaphoglossum is the most species-rich genus in PILA. Compared to the flowering plants, fern diversity as a proportion of the national fern floras is relatively high, PILA harbouring 42% of the fern diversity of Costa Rica and 50% of Panama, compared to 28–30% of the diversity of flowering plants. The relative importance of ferns in PILA may be a consequence of the relatively high proportion of PILA that is above 1000 m elevation and where the greatest diversity of ferns would be expected ( Moran 2008). Kreft et al. (2010) in a study of global patterns in pteridophyte diversity calculate the proportion of fern diversity across a range of abiotic and geographic variables. They find a mean proportion of fern diversity of 8% (SD not indicated) in montane habitats and of 6.8% (SD not indicated) in moist broad leaf forest, in contrast to an average proportion of mainland diversity of 3.6% (SD±2.5) and of island diversity of 15.3% (SD±12.6). Given the relatively high standard deviations for the above figures, the fern diversity of PILA is congruent with values for montane, moist broad-leaf forest and islands (e.g. Christenhusz 2009). If the latter were the case then this could be ascribed to PILA’s island status ca 16–3 M years ago.

Also associated with the dominance of upland vegetation formations in PILA are the high proportion of epiphytic and shrubby species and low proportion of vines compared to the national floras of Costa Rica and Panama ( Table 4). Upland vegetation formations contain the highest species diversity in PILA ( Fig.1) with peak diversity recorded at the 1601–2100 m elevation range characterised by oak forest. That peak diversity is observed for this elevation range is surprising for several reasons: this was one of the least sampled areas, it does not correspond to the largest surface area ( Table 1) or to the area of highest topographic complexity ( Solís 2009, Fig. 11) and non-fern vascular plant diversity is usually lowest at and above this elevation range in both Costa Rica and Panama ( Hammel et al. 2004, Fig. 4, Correa et al. 2004, Fig. 4).

It may be that peak diversity at this elevation range is related to the history of the area. Glacial cycles in the last 1.6 Ma provoked large changes to the extension and composition of species assemblages. Different species exhibit different climatic tolerances and as species ranges contracted and expanded moving up and down elevational gradients, diversity may have accumulated at elevations of greatest species turnover. The 1601–2600 m elevation range in PILA may have included the tree-line during glaciations ( Van der Hammen & González 1964, Islebe & Hooghiemstra 2005) providing some support for such a hypothesis.