BOTANICAL MUSEUM LEAFLETS VoL. 27, No. 5-6 
May-JUNE 1979 
THE FLOWERS OF ILEX GUAYUSA 
MELVIN SHEMLUCK* 
In 1901, Theodor Loesener described a new species of holly 
from sterile material collected in 1898 by Warsczewic in eastern 
Peru. Loesener named the holly //ex Guayusa, because the Indi- 
ans of eastern Colombia, Ecuador, and Peru used its leaves to 
prepare a medicinal and beverage tea called guayusa (or 
huayusa). 
Although the plant is well known to local people, few bota- 
nists have collected it, and it is poorly represented in the world’s 
herbaria. The great English plant-explorer, Richard Spruce, did 
not collect guayusa, although he was well acquainted with it and 
even employed it as a substitute for tea when his supply of the 
latter ran out (Schultes: “Richard Spruce and the potential for 
European settlement of the Amazon: an unpublished letter” in 
Bot. Journ. Linn. Soc. 77 (1978) 131-139). It 1s so poorly repre- 
sented in herbaria that a major United States institution 
mounted leaves from a commercially prepared wreath as their 
sole representative of the species. 
Two reasons can be offered for this poor representation. One 
is that guayusa, a cultivated plant, has been poorly collected by 
researchers interested in more academic botanical problems con- 
nected with the wild flora. Another reason, the more conceiva- 
ble, is that /lex Guayusa could not be found in flower: botanists 
are hesitant, given the time and weight constraints of collecting 
expeditions, to collect non-flowering or non-fruiting material. 
Consequently, it has been those botanists interested in economi- 
cally important species who have collected most of the speci- 
mens of this plant. 
The absence of flowers and fruit has led some botanists to 
speculate that guayusa 1s an asexually reproduced cultigen 
which has lost its flowering ability through years of selection and 
vegetative propagation by man. Like many other cultivated 
*Technical Assistant, Botanical Museum of Harvard University. 
