Solanum malacothrix
In the northwestern corner of the state of Guerrero and adjacent Jalisco, on the slopes of the Sierra Madre del Sur in the Rio Balsas drainage, in tropical deciduous forest or dry pine-oak woodland ("bosque tropical caducifolio" or "bosque de Quercus" of Rzedowski, 1978).
Solanum malacothrix is a member of the Solanum pseudocapsicum species group (Knapp, 2002) of the Geminata clade (Bohs, 2005).
Knapp, S. 2002. Solanum section Geminata (G. Don) Walpers (Solanaceae).
Flora Neotropica 84: 1-405.
Bohs, L. 2005. Major clades in Solanum based on ndhF sequences.
Pp. 27-49 in R. C. Keating, V. C. Hollowell, & T. B. Croat (eds.), A festschrift for William G. D’Arcy: the legacy of a taxonomist. Monographs in Systematic Botany from the Missouri Botanical Garden, Vol. 104. Missouri Botanical Garden Press, St. Louis.
Solanum malacothrix is most closely related and superficially quite similar to S. diphyllum, a widespread lowland Mexican species. Solanum malacothrix is distinctive in its long, soft leaf pubescence, which is unusual in the section; while S. diphyllum is completely glabrous. Solanum lasiocladum of Venezuela also possesses this type of leaf pubescence. It differs from S. malacothrix in its apiculate calyx lobes, larger flowers, and long-petioled leaves with acute apices, and I have not assigned it to any of the species groups. The mature fruits of S. malacothrix are not known, but in view of its overall similarity to S. diphyllum I would expect them to be brightly colored, borne on erect pedicels, and rather fleshy.