Solanum ivohibe is narrowly endemic to Madgascar in the Ivohibe and Andringitra areas of Fianarantsoa province. It occurs in riparian and secondary montane forests from approximately 800 to1200 m elevation.
Preliminary conservation status (IUCN 2014). Endangered (EN B1a, b iii). EOO 950 km2 (EN), AOO 12 km2 (EN). Known collections of Solanum ivohibe are currently not sufficient to document its range of occurence with any degree of confidence, but its occurrence in the fragmented wet forests of eastern Madagascar and the paucity of collections leads us to give it a preliminary status that indicates conservation concern.
Solanum ivohibe is a slender forest shrub with almost glabrous leaves on decurrent long petioles, prominent domatia on leaf undersides (Fig. 13 inset), inflorescences with a long peduncle and 10-16 flowers. It seems likely that S. ivohibe can grow as a liana. The very few collections suggest it grows along streams in mid-elevation mesic to wet secondary forests in the underexplored and exceptionally diverse area around Andrigitra National Park (Lewis et al. 1996).
Within Madagascar S. ivohibe is most similar to S. sambiranense, and to some extent also with S. imamense and S. betroka. Solanum ivohibe can be distinguished from S. sambiranense by its inflorescence bearing 10-16 (versus 3-10) flowers, calyx lobes 0.8-2 mm long tearing for up to 1mm (versus calyx lobes 4-6 mm long tearing for up to 2 mm), and minute versus larger tufts of trichomes (domatia) in the axils of the veins and midrib of the lower leaf surfaces; it also occurs further south than the distribution range of S. sambiranense. Solanum ivohibe is sympatric with S. imamense and S. betroka; it differs from these two species by its long-decurrent (versus cuneate) leaf bases, larger leaves (> 5 cm long versus shorter than 5 cm), smaller calyx, and calyx lobes < 2 mm long (versus usually > 2 mm long). D’Arcy and Rakotozafy (1994) considered S. ivohibe to be a relative of the Mayotte endemic S. macrothyrsum but with smaller leaves and inflorescences; it shares features with both S. macrothyrsum and S. sambiranense. The anthers of S. ivohibe are longer than those S. macrothyrsum (3.5-4 mm versus 2.5-3 mm), the calyx lobes are somewhat longer (0.8-2 mm versus under 0.5 mm) and more deeply divided.
Solanum ivohibe appears to occupy a somewhat higher elevation, higher moisture, and more closed canopy environment than the similar species S. betroka in the arid south, S. sambiranense in fairly dry north-west, and S. imamense in mesic niches, and the distribution range of S. ivohibe does not overlap with these species. Solanum ivohibe apprears to be sympatric with S. madagascariense around Andringitra National Park and the surrounding forests although S. madagascariense occurs in wetter forest.
The species concept of S. ivohibe adopted here has little in common with that of D’Arcy and Rakotozafy (1994). The protologue lists five collections of Solanum ivohibe and places the species in section Lemurisolanum. In our view, two of the cited collections represent other taxa: Humbert 13429 (P00349045, from Ankazondrana), that was used for the illustration in the original description, belongs to our circumscription of S. madagascariense and Peltier & Peltier 980 (P00349044, from Toamasina) belongs to our circumscription of S. humblotii. The type specimen, however, represents a distinct taxon and we recognise S. ivohibe here, with a narrow circumscription encompassing the type and two other collections (one cited by D’Arcy and Rakotozafy  from very near the type locality.
The protologue of S. ivohibe cites a holotype at P. There are in fact two duplicates, one of which (P00349043) is clearly marked as such in D’Arcy’s handwriting; we select this specimen here as the lectotype of S. ivohibe.