Solanum catombelense
Not known.
Southern Africa, from Angola and Namibia to Botswana and the northern part of South Africa; growing in grassland, savanna or mixed woodland, on sand or limestone; 0-1000 m elevation.
Solanum catombelense is a member of the Old World Clade within subgenus Leptostemonum (the spiny solanums); within that it is a member of a opprly supported containing S. tomentosum and other South African species (Vorontsova et al. 2013).
Gonçalves, A.E. 2005. Solanaceae. In: G. V. Pope, R. M. Polhill & E. S. Martins (eds.), Flora Zambesiaca 8(4): 1-124.
Vorontsova, M. S., S. Stern, L. Bohs, and S. Knapp. 2013. African spiny Solanum (subgenus Leptostemonum, Solanaceae): a thorny phylogenetic tangle. Bot. J. Linn. Soc. 173: 176-193. doi:10.1111/boj.12053
Mozambique: Shintomane or Chumtumana (Nuvunga & Petrini 7654).
Uses. Medicinal.
Solanum catombelense is a common medium sized shrub with inconspicuous flowers. The majority of specimens have a characteristic gray-brown tinge reminiscent of Chenopodiaceae, although some are yellow-green. The species concept accepted here matches that of Gonçalves (2005) and includes a fairly heterogeneous assemblage of morphologies: the type of S. catombelense is a spindly plant with small leaves, S. albotomentosum is larger-leaved, robust and hairy, and S. rautanenii has a prickly calyx. Gonçalves (2005) considered S. catombelense to be the southern extension of the S. anguivi distribution range, but the two species are largely sympatric. Solanum catombelense is unlike most S. anguivi s.l. with rounded lobes on the leaves, inflorescences with fewer flowers and fruits, and frequent occurrence of curved prickles.
Solanum catombelense is partly sympatric with many spiny Solanum species: S. burchellii, S. capense, and S. humile towards the west, S. litoraneum and S. rubetorum towards the east, and S. supinum in inland areas. The yellow-green representatives of S. catombelense with smaller leaves and straight prickles can appear similar to S. burchellii; these can be distinguished from S. burchellii by the ovate to oblong leaves 3-8 cm long (versus elliptic leaves 1.7-4(5) cm long in S. burchellii), corolla 0.9-1.3 cm in diameter (versus 1.5-2.2 cm in diameter in S. burchellii), and anthers 2.5-3.5 mm long (versus 3.5-5.2 mm long in S. burchellii). Solanum catombelense is distinguished from S. capense by its leaves 3-8 cm long (versus 1.5-2.5 cm long in S. capense) that are lobed for less than ¼ of the distance to the midvein (versus 1/3-2/3 of the distance to the midvein in S. capense). Solanum catombelense is clearly distinct from S. humile by its leaves with 4-6 pairs of primary veins (versus 2-4 pairs of primary veins in S. humile), leaf lobes extending less than ¼ of the distance towards the midvein (versus ¼-1/2 of the distance towards the midvein in S. humile), and straight or curved prickles 1-4 mm long (versus straight prickles 4-13 mm long in S. humile). Solanum catombelense differs from S. litoraneum by its chartaceous leaves with 2-4 lobes (versus membranous leaves with 1-2 lobes in S. litoraneum), 5-6 primary veins (versus 2-4 primary veins in S. litoraneum), and inflorescences 1-2.5 cm long with 1-4 flowers (versus inflorescences ca. 3 cm long with 2-14 flowers in S. litoraneum). Solanum rubetorum can be distinguished by its deeply lobed leaves and smaller trichomes on the adaxial leaf surface. The grayish almost entire leaves of S. catombelense in Botswana have been confused with those of almost entire-leaved and mostly unarmed S. supinum; the identity of S. supinum can be established by its single flowers, pentagonal corolla, and spiny calyx with conspicuously elongate lobes.
As the lectotype of S. albotomentosum we have selected the first collection cited in the protologue, the second collection (Welwitsch 6077 at K [K000414091], BM [BM000778317], and P [P00344412]) is of somewhat inferior quality and is represented by fewer duplicates. The protologue of Solanum rautanenii cites Rautanen 726a but we only found duplicates numbered Rautanen 726 and have designated the lectotype from among these.