Solanum pachyandrum
Solanum pachyandrum, known as bombona, is a spine-forming vine of the Solanum genus. It is native to southwestern Ecuador and northwestern Peru where the large juicy fruit is commonly eaten and considered a treat by children. Although the plant has been known and consumed by the indigenous people of that land, it was only published scientifically in 1914 by German botanist Friedrich August Georg Bitter.
Description
Bombona is a woody to subwoody vine growing 5+ m long that flowers from April to September in its native range in Ecuador and Peru. It differs from other related species by the presence of prickles on its pedicels and its ellipsoid, non-tapering anthers.It's often said to be spiny, but is actually prickly since the spinose structures are not derived from leaves and lack vascular bundles inside, allowing them to more easily be removed. The prickles are long, stout, and recurved.
Stems are in diameter and are and long. Sympodial units plurifoliate and do not geminate.
Leaves are pinnatifid with four to six pairs of lobes. The leaf blades in outline are in length and in width. They are oblong and around twice as long as they are wide. Their texture is chartaceous and are glabrous on both surfaces. The midrib has recurved prickles and there are four to six major lateral veins on each side of the midrib that correspond to the lobes.
Fruits are globose berries that are in diameter with a glabrous pericarp. They are purple when immature and turn yellow-orange once mature.
Seeds are about. They are light brown in color, strongly flattened, and the surfaces are minutely pitted. The testal cells of the seeds are rectangular.
Taxonomy
Phylogenetic studies suggest it is likely part of a sister group to the rest of the prickly species belonging to the subgenus Leptostemonum called S. sect. Aculeigerum. Unlike most prickly species of Solanum, these species lack stellate hairs and are characterized by plurifoliate sympodial units, branched inflorescences, presence of prickles coupled with absence of stellate trichomes, and a vine-like habit.The Solanum section Aculeigerum contains these eight species, all ranging in distribution from Mexico and Central America to Ecuador and Peru:Solanum alternatopinnatum Steud — juciri, jiquiri, or yuá-pará S. bicorne Dunal — chilacayote, tomate de chichalaca, or toronjo Solanum cobanense J. L. Gentry Solanum glaucescens Zucc. — cuatomate or zarza Solanum pachyandrum Bitter — bombona and Peru Solanum refractum Hook. & Arn. Solanum triunfense S. Knapp — quistan Solanum wendlandii Hook. f. — kishtan, cola de gato
S. pachyandrum is differentiated from S. refractum by its white flowers and wider anthers and both are differentiated from the rest of the species by the fact that all filaments within a flower are of equal length.