﻿A new species and new records of Solanum (Solanaceae) from Colombia

﻿Abstract We describe a new species of the Geminata clade of Solanum from Colombia and provide new distributional records for two additional Solanum species, recorded here for the first time in Colombia. Solanumbohsii J.D. Tovar, sp. nov. is morphologically similar to S.chlamydogynum Bitter from Venezuela of the Solanumsessile species group (Geminata clade). These two species can be distinguished by trichome morphology, as well as colour and density of the indumentum. In addition, we report new range expansions into Colombia for two species: S.tanysepalum S.Knapp (Geminata clade) known previously only from Venezuela and S.verecundum M.Nee (Brevantherum clade) from Ecuador and Peru.


Introduction
Solanum L., with ca. 1,250 species, is the largest genus in the Solanaceae and one of the 10 most species-rich genera of flowering plants (Frodin 2004;Gagnon et al. 2022). The genus has a worldwide distribution with a centre of diversity in South America concentrated in the Andes (Knapp 2002a). A total of 164 species, with 10 of them endemic, are found in Colombia alone, where Solanum species occur in all biogeographic regions of the country, from sea level to 4,200 m in elevation (Orozco et al. 2015).
Molecular studies have divided Solanum into 12 major clades (Bohs 2005;Weese and Bohs 2007;Särkinen et al. 2013;Gagnon et al. 2022) that have redefined the infrageneric classification of the genus and are being used as informal infrageneric groups in Solanum. The Brevantherum and Geminata clades are among the largest of the non-spiny neotropical clades of Solanum with ca. 100 and 150 species, respectively (Knapp 2008;. The two clades have similar distributions with centres of diversity and endemism in the Atlantic Forest of Brazil and the tropical Andes (see Knapp et al. 2015;. Both clades are unarmed and woody (shrubs or trees) but differ in their trichome type and inflorescence position and morphology. Species of the Brevantherum clade have mostly stout and highly branched inflorescences positioned in branch forks (i.e. terminal inflorescences in dichasially branching stems) and most species have stellate trichomes . Members of the Geminata clade, in contrast, all lack stellate trichomes and have mostly monochasial branching with inflorescences that are leaf-opposed or rarely terminal or internodal (Knapp 2008;Knapp et al. 2015).
Here we describe a new species for the Geminata clade and provide new records of two species from the Brevatherum and Geminata clades of Solanum for Colombia with field photos. These discoveries were made during herbarium and fieldwork conducted for a broader phylogenetic study of the Geminata clade. The discovery of the new species from the Geminata clade is not surprising considering members of this clade have an intricate taxonomy due to similar morphology (Knapp 2008) and are often poorly known because they occur in forest understorey habitats, where they are often inconspicuous, locally rare and rarely collected (Knapp et al. 2015). In fact, most undetermined specimens of Solanum in tropical herbaria are from the Geminata clade and it is, hence, not surprising that a new species was found during our study of the clade in Colombia.

Methods
We examined specimens from the FAUC, HUA, HUQ and JBB Herbaria (acronyms from Index Herbariorum; http://sweetgum.nybg.org/science/ih). For the new species here described, duplicates of paratypes are still awaiting distribution to other countries. Descriptions are based on field observations and herbarium specimens. Preliminary conservation status assessments were done using the IUCN Red List Categories and Criteria (IUCN 2017), based on extent of occurrence (EOO) and area of occupancy (AOO) calculated with the GeoCat tool (www.geocat.kew.org; Bachman et al. 2011). For the AOO calculation, a cell size of 2 km 2 was used. The morphological cluster species concept of Mallet (1995) was used in defining a species.
Description. Shrubs or small trees, 2-7 m tall; stems winged, greenish-brown when young, turning brown with age, young stems pubescent with translucent simple or furcate 4-8-cellular trichomes. Sympodial units difoliate and geminate, leaves ovate to obovate, glabrous adaxially or with translucent trichomes along the mid-rib and secondary veins like those on stem, abaxially pubescent with trichomes in the mid-rib and along the secondary and tertiary veins; major leaves 18-35 (45) × 12-16 cm, with 12-15 pairs of main lateral veins, these often strongly parallel, the apex acute, base oblique and decurrent on to petiole; petioles 1-2 cm long, pubescent with translucent trichomes, like those on stem; minor leaves differing only in size, not in shape, 8-9.5 × 4-5 cm, with 6-9 pairs of main lateral veins, adaxially and abaxially pubescent along the mid-rib and main lateral veins like those on stem, the apex acute or rounded, base oblique and decurrent on to petiole; petiole 0.5.-0.7 cm long, pubescent with translucent trichomes, like those on stem. Inflorescences leaf-opposed, forked and erect, 20-50 flowered, peduncles 1.5-2.5 cm, with unbranched and uniseriate trichomes, like those on stem, pedicel scars densely spaced, not overlapping, pedicels 0.5-1 cm long, deflexed, thickened at the apex and purple in live plants. Buds globose, with the corolla strongly exserted from the calyx tube prior to anthesis. Flowers 5-6-merous, all perfect; calyx tube cyathiform, 2-3 mm long, the lobes deltoid abruptly reduced and hooded at the apex, 1.5-2 × 1.8-2.2 mm, abaxially glabrous or densely pubescent with trichomes like those of the young stem and with a tuft of hairs at apex; corolla 1.5-2 cm in diameter, white, fleshy, lobed ca. ¾ of the way to the base, the lobes 0.7-0.9 × 3-4 mm spreading or deflexed at anthesis, glabrous and cucullate at the tips; anthers 4-6 × 1.2-1.7 mm, poricidal at the tips, sagittate at the base; free portion of the filaments 0.2-1.2 mm long; ovary glabrous; style 0.5-0.7 mm long, terete, glabrous, stigma capitate, light green in live plants. Fruit a globose green berry, 1-1.2 cm in diameter, glabrescent or with a few scattered trichomes like those on stem and an apical scar, green at maturity; fruiting pedicels 1.5-2 cm long, erect, woody and somewhat rugose, distally enlarged, the calyx constricted and with lobes woody in fruit. Seeds ca. 80 per fruit, 2.5-3.5 × 2-2.5 mm, flattened-reniform, greyish when dry, the margins incrassate, the surfaces minutely pitted. Chromosome number not known.
Distribution and ecology. Solanum bohsii is known only from three localities in the western slopes of the central Andean cordillera in Colombia in the Departments of Caldas, Quindio and Risaralda (Fig. 3) where it inhabits secondary forest edges between 1,900-2,300 m elevation, forming groups of up to 10 individuals.  Phenology. According to the collections studied, S. bohsii produces flowers and fruits throughout the year.
Etymology. The specific epithet honours Lynn Bohs, an American botanist and expert in the Solanaceae family, who has made great contributions to the understanding of systematics and evolution of the genus Solanum over the last 30 years.
Notes. According to its morphology, S. bohsii is a member of the Solanum sessile species group (sensu Knapp 1991; 2002b) with difoliate and geminate sympodial units, large leaves and large branched inflorescences and ovoid-reniform seeds. It is easily distinguished from the other species in the group by its large leaves up to 45 cm long and the secondary veins strongly parallel in mature leaves. Solanum bohsii is morphologically similar to S. chlamydogynum from Venezuela with which it shares the winged stems, the fleshy large flowers with cucullate lobes and the presence of trichomes in both leaf surfaces. However, trichomes of S. bohsii are simple or, at most, furcate, translucent and less abundant compared to S. chlamydogynum which has dendritic ochraceous trichomes. Furthermore, inflorescence peduncles are less pubescent in S. bohsii, while densely pubescent with ochraceous trichomes in S. chlamydogynum. Solanum bohsii has distinctive mature fruits in dry material with a network-like pericarp, resembling the venation of leaves. From the other species in the Solanum sessile species group, it is easily recognised either by the pubescence, the winged stems, the large leaves or the large flowers with cucullate lobes (see Knapp 1991;2002b).
Notes. Solanum tanysepalum (Fig. 4a) is a species previously known only from the Cordillera de la Costa in Venezuela in cloud forest from 1,000 to 1,700 m elevation.
Our new records presented here extend the distribution to the departments of Huila and Magdalena in Colombia (Fig. 5). The species belongs to the Solanum arboreum species group in the Geminata clade and can be easily recognised by the long-acuminate calyx lobes that are persistent and somewhat woody in fruit (Knapp 2002a, b). More information and a complete description are available at: https://solanaceaesource. myspecies.info/solanaceae/solanum-tanysepalum.   (Fig. 4b) was previously known from montane forests in Peru and Ecuador . Our new records presented here extend the distribution to Colombia to the Departments of Caldas, Quindio and Valle del Cauca (Fig. 5). The species belongs to the Brevantherum clade and is related to the species traditionally included in section Brevantherum Seithe (Tovar et al. 2021). Solanum verecundum can be easily recognised by the membranaceous leaves, stellate-lepidote trichomes (with partially fused rays) in both leaf surfaces and puberulous orange-coloured fruits at full maturity. More information and a complete description are available at: https://solanaceaesource.myspecies.info/solanaceae/solanum-verecundum Specimens examined. Colombia. Caldas: Municipio de Villamaria, ruta del condor, carretera entre la Telaraña y La Guyana, 4°57'18.5"N, 75°30'03.3"W, 2,000 m elev., 29 Nov 2021 (fl,fr), J.D. Tovar & M.A. Buitrago 487 (FAUC). Quindio: Municipio de Génova, por la trocha que conduce a Pijao, camino al Cedral, 1,800 m elev.