Solanum apiahyense Witasek, Denkschr. Kaiserl. Akad. Wiss., Wien Math.-Naturwiss. Kl.79: 343. 1910.

Knapp, Sandra, Stehmann, Joao Renato & Giacomin, Leandro L., 2015, New species, additions and a key to the Brazilian species of the Geminata clade of Solanum L. (Solanaceae) in Brazil, PhytoKeys 47, pp. 1-48 : 5-8

Solanum apiahyense Witasek, Denkschr. Kaiserl. Akad. Wiss., Wien Math.-Naturwiss. Kl.79: 343. 1910. Figures 1C, D, 4

Type.

Brazil. São Paulo. Apiahy, Feb 1891(fl), J.I. Puiggari 3711 (lectotype, designated here: WU [WU0037965]).

Description.

Small erect shrubs, to 50 cm tall, often rhizomatous with a horizontal woody branch bearing several adventitious roots; young stems moderate to densely pubescent, with 4-8-celled hyaline trichomes to 2 mm long; new growth drying dark, densely pubescent; bark of older stems pale gray, glabrescent, not exfoliating. Sympodial units 3-plurifoliate, normally not geminate, if geminate, with leaves differing only in size. Leaves simple, 3.4-11 × 0.8-4 cm, elliptic to narrowly elliptic, membranous, slightly discolorous, shiny green adaxially when fresh, drying pale green beneath, dark above, not shiny, both surfaces moderate to densely pubescent with hyaline simple uniseriate trichomes 1-2 mm long with up to 5 cells, sometimes with a multicellular base (but see comments); primary veins 5-7 pairs, the midrib and primary veins darker abaxially, raised; base attenuate to acute, slightly decurrent onto the petiole, mostly symmetric; margins entire, not revolute, ciliate with antrorse hyaline trichomes; apex attenuate to acuminate; petioles 2.5-15 mm long, densely pubescent, with trichomes like those of the stems and leaves. Inflorescences 1.7 to 3.3 cm long, mostly lateral or less often strictly opposite the leaves, unbranched, with 3-5 flowers, moderate to densely pubescent, with hyaline trichomes like those of the stems and leaves; peduncle 4-15 mm long; pedicels 5 to 11 mm long, articulated at base; pedicel scars closely spaced ca. 1 mm apart. Buds globose to slightly elongate, the corolla mostly included in the calyx tube, exserted only just before anthesis. Flowers all perfect, 5-merous. Calyx tube up to 1 mm long, conical, getting reflexed, the lobes up to 0.9 mm long in flower, to 1.7 mm long in fruit, approximately 1.6 mm wide, acuminate and discretely keeled, adaxially, glabrous or papillose, covered with tiny 1-2-celled glandular trichomes, abaxially densely pubescent, with trichomes as those of the stem, or sometimes even longer, with 2.5 mm, and normally 5-6 cells. Corolla 1.5-1.7 cm in diameter, white, stellate, membranous, lobed from 2/3 to 3/4 of the way to the base, the lobes 7.5-9 mm long, 3-3.5 mm wide, reflexed at anthesis, deltate to lanceolate, glabrescent adaxially, abaxially sparsely pubescent, with 3-4-celled delicate simple trichomes of ca. 0.5 mm along the midvein, with tufts of few celled tiny trichomes less than 0.1 mm long on the tips and margins. Stamens 3.2-3.6 mm long; filament tube ca. 0.5 mm long, the free portion of the filaments up to 0.6 mm long equal in length or slightly unequal, and when so, one filament slightly longer (barely visible in dried material), glabrous; anthers 2.6-2.8 mm long, 1.6-1.8 mm wide, ellipsoid, slightly connivent, yellow, slightly sagittate at the base, the pores directed introrsely, opening into longitudinal slits at maturity. Ovary glabrous; style 4.2-5 mm long, white, straight, glabrous; stigma capitate, light green. Fruit a globose berry 0.7-1.4 cm in diameter (immature?), dull green, drying dark, the pericarp glabrous and not markedly shiny; fruiting pedicels 1.2-2 cm long, ca. 0.7 mm in diam. at the base, to 1.1 mm at the apex, with a slight constriction at the receptacle; calyx lobes in fruit somewhat enlarged. Seeds approximately 70 per fruit, known only from very young fruits, possibly flattened and with a marginal wing when fully developed.

Distribution.

In the Serra do Mar mountain range in the Brazilian states of Paraná, Santa Catarina and São Paulo (Figure 5).

Ecology.

Solanum apiahyense is a rare and inconspicuous shrub of the understory and edges of well preserved and secondary fragments of the montane Brazilian Atlantic rainforest (Floresta Ombrófila Densa of IBGE 2012; Mata Atlântica), from 600 to 900 m. Although most collections are from well preserved sites, Solanum apiahyense is not exclusively associated with shaded environments. The species is also found along unpaved roadsides close to the type locality.

Phenology.

Fertile specimens are known from September to February. Mature fruits were observed only in October.

Etymology.

The epithet refers to the type locality, the city of Apiaí in southern São Paulo state.

Preliminary conservation status ( IUCN 2014).

Endangered (EN) B1; B2 ab (ii, iii, iv). EOO 3,208 km2 (EN); AOO 16 km2 (EN). Although the species occurs in a wide latitudinal range, it is locally rare, and is known from only six localities. None of the known populations are from within protected areas.

Notes.

Solanum apiahyense , described more than a century ago ( Witasek 1910), has not been assigned to any infraspecific group of Solanum so far. Recent phylogenetic analysis using molecular data ( Giacomin 2015) has shown it to be closely related to Solanum trachytrichium , which was previously assigned to the Geminata clade ( Knapp 2002a, 2008) and to its own subsection when originally described (subsect. Silicosolanum Bitter; Bitter 1919). Bitter (1919) based this on the unusual trichome morphology of hooked cells arising from a flattened multicellular base that give the leaves a feeling of sandpaper in herbarium specimens. Although molecular data support a close relationship between Solanum apiahyense and Solanum trachytrichium , the affinities of this clade are not clear-cut. Data from combined markers place it as sister to all other Geminata clade species, but with low support. In analyses of individual markers, it emerges as sister to either the Brevantherum or Geminata clades depending upon the marker used ( Giacomin 2015).

Morphologically both taxa are easy to distinguish from most other Geminata species, and have the following assemblage of characters: both are small shrubs with leaves mostly not geminate, they have leaf trichomes with an expanded multicellular base and relatively large flowers (>1.5 cm in diameter). Among them, Solanum apiahyense and Solanum trachytrichium are easy to distinguish: Solanum trachytrichium has a unique scabrous indumentum on the leaf surfaces and stems, composed of short unicellular hooked trichomes on a mound-like multicellular base, while in Solanum apiahyense the surface is not rough to the touch, and although some trichomes with multicellular bases can be seen on leaves, these are translucent, very long (ca. 2 mm) and mostly 5-7-celled. These long trichomes of Solanum apiahyense are easily seen on the new growth, while Solanum trachytrichium trichomes are not visible to the naked eye. In addition, the flowers of Solanum apiahyense are slightly smaller, 1.5-1.7 cm in diameter versus 1.6-2.2 cm in Solanum trachytrichium .

In the past, the epithet Solanum apiahyense has been applied to more than one species of the Solanum inornatum group (part of the Brevantherum clade; Giacomin and Stehmann 2014) by various Solanum taxonomists, although they are now known to not be closely related. Although members of the Solanum inornatum group (e.g., Solanum inornatum Witasek, Solanum bradei Giacomin & Stehmann and relatives) and Solanum apiahyense are similar in habit and in having pubescence of long, translucent trichomes, they can be readily distinguished by close examination of the trichomes; those of Solanum apiahyense are multicellular with 5-7(8) cells while those of members of the Solanum inornatum group are mostly 3-celled (probably representing modified stellate hairs, Giacomin and Stehmann 2014). Fruiting specimens of Solanum apiahyense have peduncles longer than 1 cm and the pedicels are strongly apically expanded and constricted just beneath the calyx lobes (see Figure 1C), while in the species of the Solanum inornatum group species, the peduncles do not exceed 1 cm and the pedicels are never apically expanded with a distal constriction. Examination of trichomes with a 10 × hand lens will allow easy identification of both flowering and fruiting material.

The type material found at WU (Puiggari 3711) consists of a single sheet, and does not match the photograph of a dried specimen in the original publication ( Witasek 1910: tab. 30, fig. 2). It should therefore be treated as an isotype ( Mentz and Oliveira 2004). As no further material could be found in other possible herbaria where J.I. Puiggari deposited his collections, the specimen at WU is here designated as a lectotype.

Specimens examined.

BRAZIL. Paraná: Mun. Cerro Azul, Serra Paranapiacaba, 20 Nov 1970 (fl), G. Hatschbach & O. Guimarães 25528 (MBM, RB); Mun. Doutor Ulysses, Barra do Teixeira, 16 Sep 2006 (fl, fr), J.M. Silva (HUFU, MBM, RB). Santa Catarina: Mun. Vidal Ramos, Mina Bugre, 27°21'35"S, 49°19'12"W, 598 m, 22 Sep 2009 (fl, fr), A. Korte & A. Kniess 243 (BHCB, FURB). São Paulo: Mun. Bom Sucesso de Itararé, Estrada de terra para Bom Suceso de Itararé, Próximo a Mineração de ouro São Judas (3 km após), 24°19'13.19"S, 49°12'49.49"W, 891 m, 11 Oct 2009 (fl, fr), L.L. Giacomin et al. 1097 (BHCB, BM, NY, RB); Mun. Bom Sucesso de Itararé, Estrada Bom Sucesso de Itararé, 2 km antes da Mineração São Judas, 24°19'13"S, 49°13'04"W, 15 Dec 1997 (fr), J.M. Torenzan et al. 647 (IAC, ESA, FUEL, SPSF, UEC).