Manual de Plantas de Costa Rica 145 
Raphia, the predominance of Astrocaryum alatum is notable. A few large and conspic- 
uous herbaceous swamps, comprised of species such as Eichhornia crassipes, Pistia 
stratiotes, Salvinia spp., and various others (particularly grasses and sedges), are also 
found in this area. Eichhornia crassipes sometimes covers waterways so densely as to 
impede navigation (Boza & Cevo, 2001). 
The edges of the large canals traversing much of this region are the preferred habi- 
tat of numerous other species, such as Acacia ruddiae, Allamanda cathartica, Amanoa 
guianensis, Andira inermis, Annona glabra, Combretum cacoucia, Corynostylis ar- 
borea, Crudia glaberrima, Desmoncus schippii, Ficus insipida, Hiraea faginea, Lon- 
chocarpus densiflorus, L. luteomaculatus, Luehea seemannii, Machaerium falciforme, 
Pachira aquatica, Tabebuia rosea, Uncaria tomentosa, Vochysia guatemalensis, and 
Zygia longifolia. Occasionally, Crinum erubescens forms dense stands along these wet 
margins, where the water level does not rise above the tops of the plants. Large tracts 
of the fern Acrostichum aureum and the aroid Montrichardia arborescens are also con- 
spicuous elements of this region. 
As was already pointed out in the discussion of beach vegetation, the vegetation 
near the coast is characterized by species that prefer sandy soils, the limit of which is 
the high-tide level. Of these species, the most obvious is the coconut (Cocos nucifera), 
while others that bear mention include Annona glabra, Canavalia rosea, Chrysobal- 
anus icaco, Coccoloba uvifera, Dalbergia brownei, D. ecastaphyllum, Dioclea wil- 
sonil, Inga multijuga, Ipomoea pes-caprae, Morinda citrifolia, Talipariti tiliaceum, 
Terminalia catappa, Vigna adenantha, Xylosma panamensis, Zygia inaequalis, and 
Z. latifolia. 
Baja Talamanca. We consider this region to extend from just south of the Rio 
Matina to the border with Panama; as one moves along this region in a southeasterly 
direction, the climate becomes somewhat drier and numerous plants particular to these 
conditions are found. The Talamanca mountain range is close to the coast here, so areas 
of swamp forest are much less extensive and the hilly terrain harbors a rather distinc- 
tive flora. 
The swamp forests of this area have quite the same flora as those of the previous 
subregion with similar edaphic conditions. Nevertheless, some species dominant in 
those forests, e.g., Pentaclethra macroloba, here begin to drop out, while others, such 
as Anacardium excelsum, Brosimum alicastrum, Cordia diversifolia, Hura crepitans, 
Poulsenia armata, Prioria copaifera, Unonopsis storkii, and Xylosma panamensis, be- 
come more prevalent. The floristic differences between here and areas to the north are 
most notable on well-drained soils, which favor the development of species such as 
Abarema barbouriana, Adenophaedra grandifolia, Chloroleucon eurycyclum, Cleid- 
ion castaneifolium, Dipteryx oleifera, Manilkara spectabilis, Minquartia guianensis, 
Naucleopsis ulei, Ormosia amazonica, Otoba acuminata, Pavonia oxyphyllaria, Pleu- 
