Manual de Plantas de Costa Rica 175 
vahliana, Eleocharis minutissima, Erythroxylum havanense, Eugenia biflora, Euphor- 
bia ocymoidea, Furcraea cabuya, Guadua amplexifolia, Guaiacum sanctum, Hyptis 
brachiata, Ipomoea ophioides, Leptocoryphium lanatum, Lippia oxyphyllaria, Luziola 
fragilis, Lysiloma divaricatum, Manihot aesculifolia, Mentzelia aspera, Miconia albi- 
cans, Morisonia americana, Operculina pteripes, Orthopappus angustifolius, Panicum 
haenkeanum, P. stenodes, Paspalum minus, P. multicaule, P. standleyi, Pereilema crini- 
tum, Polygonum acuminatum, Rhynchospora brevirostris, R. eximia, R. filiformis, R. 
globosa, R. holoschoenoides, R. tenerrima, Ruellia inundata, R. nudiflora, Schizachy- 
rium sanguineum, Sciadodendron excelsum, Selenicereus wercklei, Setaria liebmannii, 
S. vulpiseta, Sorghastrum incompletum, Stenocereus aragonii, Streptogyna americana, 
Tetramerium nervosum, Tonina fluviatilis, Tournefortia volubilis, Trachypogon plumo- 
sus, and Trigonia rugosa. Some species found here are widespread dry forest elements, 
reaching also into the Osa and Burica Peninsulas, e.g.: Astronium graveolens, Brassa- 
vola nodosa, Cnestidium rufescens, Curatella americana, Inga vera, Licania arborea, 
Pseudobombax septenatum, Psychotria horizontalis, P. pubescens, Sterculia apetala, 
Trigonia rugosa, Triplaris melaenodendron, and Ximenia americana. 
On the other hand, close to 65 species are known in Costa Rica only from the lower 
basin of the Rio Grande de Térraba, among them Abutilon giganteum, Benjaminia re- 
flexa, Billbergia macrolepis, Bonamia trichantha, Calycolpus warszewiczianus, Cassia 
moschata, Clitoria pinnata, Colubrina heteroneura, Croton skutchii, C. tonduzii, Eri- 
ochloa distachya, Gymnopogon fastigiatus, Inga bracteifera, Lindackeria laurina, 
Lonchocarpus cf. chiricanus, Ludwigia torulosa, Miconia chrysophylla, M. dolichor- 
rhyncha, M. ibaguensis, M. matthaei, M. rubiginosa, Ocotea aurantiodora, Odonellia 
hirtiflora, Panicum caricoides, P. discrepans, Paratheria prostrata, Paspalum bosci- 
anum, P. lineare, P. stellatum, Pera oppositifolia, Piptocoma discolor, Porcelia mag- 
nifructa, Rhynchospora albescens, R. armerioides, R. pubera, Sagittaria rhombifolia, 
Scleria anceps, S. purdiei, Serjania grandis, S. grosii, S. paucidentata, Sporobolus pili- 
ferus, Thrasya hitchcockii, T: petrosa, T. trinitensis, Tynanthus croatianus, Utricularia 
myriocista, and Xylopia aromatica. 
It is also worth noting that the flora of this basin has certain affinities with that of 
the northern Caribbean zone, especially the Rio Sapoa basin and the Llanura de Los 
Guatusos. Some of the species in common with that region are Acrocomia aculeata, 
Attalea rostrata, Cochlospermum vitifolium, Copaifera aromatica, Enterolobium schom- 
burgkii, Mayaca fluviatilis, Miconia chamissois, Palicourea triphylla, Schefflera mo- 
rototoni, Tonina fluviatilis, Xylopia frutescens, Xyris jupicai, X. laxifolia, and many 
grasses and sedges. Also, some of the species of this area are shared with the north- 
eastern part of the Mosquitia of Honduras and Nicaragua, which in the latter country 
reaches roughly to the southern limit of naturally occurring Pinus (N. Zamora V., pers. 
obs.). Yet other elements of this basin appear to have come from the South American 
savanna formations known as “cerrado,” introduced along the western flanks of the Ta- 
lamanca and Chiriqui massifs (GOmez P., 1986). 
