Manual de Plantas de Costa Rica 137 
1 ha plots (N. Zamora V., unpublished data). Here one can find numerous Amazonian 
elements that are also quite common on the Osa Peninsula, such as Balizia elegans, 
Caryodendron angustifolium, Casimirella ampla, Chrysophyllum_ colombianum, 
Couma macrocarpa, Dendrobangia boliviana, Doliocarpus brevipedicellatus, Elae- 
oluma_ glabrescens, Elvasia elvasioides, Eschweilera integrifolia, E. longirachis, 
Gouania colombiana, Humiriastrum diguense, Lecointea amazonica, Licania affinis, 
Malanea erecta, Miconia sparrei, Mimosa myriadenia, Ocotea pullifolia, Panopsis mu- 
cronata, Parinari excelsa, Pouteria cuspidata, Pradosia atroviolacea, Pterocarpus vi- 
olaceus, Qualea paraensis, Randia altiscandens, Ruptiliocarpon caracolito, Sarcaulus 
brasiliensis, Tapura guianensis, Vochysia allenii, and Vouarana anomala. It is also 
worth mentioning that the family Lecythidaceae, with six or seven species, is unusually 
diverse in this region, as also on the Osa Peninsula. The northern part of this plain is 
also the only place in the country where Podocarpus guatemalensis 1s relatively abun- 
dant (compared to a single individual known from the Osa Peninsula). 
At the southern extreme of this plain—that is, at the base of the Cordillera Central, 
where some of the above-mentioned species are also found—the climate is wetter, 
without marked seasonality, and the topography is flat, with few hills. Nevertheless, 
even in this southern area, a few of the same species are found that occur in drier areas 
such as the Llanura de Los Guatusos. Curiously, some of these elements appear to be 
more frequent on hills, e.g., Calliandra tergemina, Cecropia peltata, Cochlospermum 
vitifolium, Davilla kunthii, D. nitida, Doliocarpus brevipedicellatus, Henriettella odor- 
ata, Inga cocleensis, Licania sparsipilis, Miconia minutiflora, M. multispicata, M. ste- 
vensiana, Paullinia fibrigera, Quiina schippii, Ryania speciosa, Senna undulata, Sloanea 
tuerckheimii, and Zuelania guidonia. 
In general, the forests of this southern part of the Llanura de San Carlos are char- 
acterized by the presence of many arborescent palms such as Euterpe precatoria, Iriar- 
tea deltoidea, Prestoea decurrens, Socratea exorrhiza, and Welfia regia. Beyond these, 
the canopy is dominated by such species as Ampelocera macrocarpa, Aspidosperma 
spruceanum, Balizia elegans, Carapa guianensis, Ceiba pentandra, Chrysophyllum 
colombianum, Dialium guianense, Dipteryx oleifera, Dussia macroprophyllata, Hier- 
onyma alchorneoides, Hymenolobium mesoamericanum, Lecythis ampla, Otoba novo- 
granatensis, Pentaclethra macroloba, Pouteria calistophylla, P. torta, Qualea paraensis, 
Sacoglottis trichogyna, Sclerolobium costaricense, Stryphnodendron microstachyum, 
Terminalia oblonga, Vatairea lundellii, Virola koschnyi, V. sebifera, Vochysia allenii, 
and V. ferruginea. Frequently, the subcanopy is dominated by such species as Anaxa- 
gorea crassipetala, A. phaeocarpa, Ardisia fimbrillifera, Capparis pittieri, Carpo- 
troche platyptera, Colubrina spinosa, Cryosophila warscewiczii, Eschweilera costari- 
censis, Faramea occidentalis, Ferdinandusa panamensis, Geonoma congesta, Guarea 
rhopalocarpa, Miconia spp., Naucleopsis naga, Parathesis trichogyne, Protium spp., 
Rinorea spp., Warszewiczia coccinea, and Welfia regia. Smaller palm species such as As- 
terogyne martiana, Bactris hondurensis, Calyptrogyne ghiesbreghtiana, and Geonoma 
