MIONE, THOMAS1*, SEGUNDO LEIVA G.2, and DONALD H. LES3. 1Biological Sciences, Central Connecticut State University, New Britain CT 06050-4010; 2Museo de Historia Natural, Universidad Privada Antenor Orrego, Trujillo, Peru; 3Ecol. & Evol. Biol., University of Connecticut, Storrs, CT 06269-3043. - The biogeography of South American Jaltomata (Solanaceae).
The forty or so South American species of the genus Jaltomata
are morphologically and ecologically diverse and widely distributed in
the Andes from Venezuela to Bolivia. Both herbs and shrubs are
represented; corollas are rotate, campanulate or tubular, or even
urceolate with a revolute limb. In South America the genus has a broad
altitudinal distribution, from sea-level to over 4,000 m. Five species
grow in widely separated fog-dependent islands of vegetation
(lomas formations) in the otherwise hyper-arid coastal desert
of Peru. Lomas species do not constitute a monophyletic group,
suggesting repeated colonization events to lomas formations
from the Andes. Four of the lomas species are endemic while one
lomas species (J. aspera (R. & P.) Mione) also grows in
the Andes. Two of the lomas species (J. umbellata (R. &
P.) Mione & M. Nee, and J. aspera) have copious red/orange
nectar, as do 8 exclusively Andean species. Although red/orange nectar
occurs only in certain Jaltomata species of Peru and northern
Bolivia, its presence is not correlated with habitat, nor altitude nor
with a particular corolla form. A decade ago only three species of
Jaltomata were known from northern Peru. Now, we know of 29
species of this genus in this region, 23 of which S. L. G. and T. M.
collected during recent field work. The increase in taxa is
attributable to the discovery of entirely new distinct and defendable
biological entities, not to the division of previously named species.
Key words: biogeography, Jaltomata, lomas formation, Red Nectar, Solanaceae