March 2003
·
1,101 Reads
·
4 Citations
orchids constitute one of the most species-rich families of plants in the world, and Colombia possesses a large proportion of this number, including around of 4000 species, grouped into 205 genera. With an estimated number of 4000 species in about 29 genera, the subtribe Pleurothallidinae is one of the most diverse groups within the family, accounting for 15-20% of all orchid species (Luer 1986). This subtribe, restricted to the New World, includes Lepanthes, a genus with about 800 species (therefore, probably one of the most diverse genera in Pleurothallidinae). It is distributed from Mexico to Boli- via, including the Antilles (Luer 1996a). Colombia with 270 species (Taxonomic List) and Ecuador with 332 (Luer 2002) are probably the countries with the highest diversity of Lepanthes. Mexico has 60 species (Salazar & Soto 1996), Costa Rica 95 (Pupulin 2002), and Puerto Rico nine (Ackerman 1995). A significant number of species are limited in distribution, resulting in high levels of endemism, but many other species are rather widely distributed. Most species inhabit cloud forests where temperature is low and humidity high. The name Lepanthes is derived from the Greek, meaning "a scale" and "a flower", what makes reference to the small, scale-like flowers characteristic of the genus. Morphological characters used to define the genus include lepanthiform sheaths of the ramicauls and a usually successively flowered racemose inflorescence. The sepals are prominent, and the petals vary in shape, but they are almost always transversely bilobed (Luer 1996a). They are variously colored and delicate, and the lip is highly specialized.