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