Tradescantia schwirkowskiana Funez, Hassemer & J. P. R. Ferreira 2016, sp. nov.
Creators: name: Funez, Luís Adriano
name: Hassemer, Gustavo
name: Ferreira, João Paulo Ramos
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Liliopsida
Commelinales
Commelinaceae
Tradescantia
Tradescantia schwirkowskiana

description: Tradescantia schwirkowskiana Funez, Hassemer & J.P.R.Ferreira, sp. nov. Figs. 1–3.
Stems densely branched, with a line of trichomes opposite to the insertion of the leaf blade. Leaf blades membranaceous with secondary veins conspicuous on both sides, flat, elliptic to broadly elliptic, margins ciliate. Cincinni bracts not saccate at the base.
Type: — BRAZIL. SANTA CATARINA: São Bento do Sul: Borda da ferrovia às margens do Rio Banhados, 16 November 2015, L. A. Funez & P. Schwirkowski 5037 (holotype FURB 50791 [Fig. 1], isotypes C, HURB).
Herbaceous plants, 20–45 cm tall. Stems erect, densely branching at base, and branching frequently axillary, radicant at the lower nodes, with 4–6 nodes, internodes 2.5–17.0 cm long, shorter in the basal portion ca. 2.5–10.0 cm becoming longer in the apical portion, to 17 cm, 1.0–4.0 mm wide, dark green, glabrous and pilose only along a line opposite to leaf insertion, with very short trichomes (ca. 0.2–0.5 mm long). Leaf blades flat, 2.3–7.1 × 1.3–1.8 cm, sessile, elliptic to broadly elliptic, discolorous, adaxial surface dark green, midvein conspicuous and secondary veins visible on both sides, abaxial surface slightly light green, glabrous on both faces, margin short-ciliate, base obtuse, apex acute; sheath 0.4–1.3 × 0.4–0.7 cm, with longitudinal streaks, pilose with large multicellular trichomes concentrated at the apex of the lateral margin, 1.0–3.0 mm long. Inflorescences terminal and axillary, a pedunculate double-cincinni fused back to back, 1.3–1.5 × 0.9–1.0 cm, subtended by a pair of unequal opposite foliaceous bracts, not saccate at base 0.7–3.3 × 0.3–1.1, peduncle 0.8–6.3 cm long, glabrous with one line of short trichomes (like on the stem); 7–28 pedicellate flowers, pedicels 9.0 mm long, glabrous or with sparse multicellular trichomes, vinaceous. Sepals 3, free; 3.0–5.0 × 2.0–3.0 mm, ovate-elliptic, apex acute, glabrous, except in the angles with multicellular trichomes 0.6–1.5 mm, green or vinaceous. Petals 3; free, 7.0–9.0 × 3.0– 3.5 mm, broadly ovate, apex acute, white. Stamens 6, subequal, filaments white, ca. 3.0 mm, with dense moniliform trichomes ca. 3.0– 4.5 mm long, anthers basifixed, 0.9–1.2 × 0.4–0.5 mm, with connective expanded, yellow, rhomboid, thecae ellipsoid, yellow, longitudinally dehiscent, pollen yellow. Stigma conical, style 3.0– 3.3 mm long; ovary 0.8–1.2 × 0.8–1.0 mm, globose, glabrous, tricarpellate, 1–2ovules per locule. Capsule, 3.0–3.2 × 1.8–2.1 mm, cylindrical, light brown, smooth, glabrous, pedicels curved down in fruiting. Seeds 1.1–1.2 × 1.0 mm, dorsoventrally flattened, ellipsoid with basal portion truncate, dark grey, testa rugose, embryotega dorsal; ventral face with a blackish prominent hilum from the base to ca. 2/3 of the length. Figs. 1–3.
Etymology:—The specific epithet is named after Paulo Schwirkowski, a notorious naturalist and plant collector from São Bento do Sul municipality, who for many years has been contributing to the knowledge of the flora of Santa Catarina.
Phenology:—Confirmed flowering and fruiting: October–December (spring and early summer). This information is based on our field observations, and also on the revision of herbarium materials.
Distribution:— Tradescantia schwirkowskiana is only known from one locality in São Bento do Sul municipality, Santa Catarina (Fig. 4).
Habitat:—Araucaria forest edges, in northern plateau of Santa Catarina, in humid areas.
Conservation status:—Critically endangered (CR). This species is only known from two collections from the same locality.There is an intense, on-going deforestation in the northern plateau of SC, due to wood extraction especially to supply the charcoal black market, but also to give way to silvicultural plantations, agriculture and pasture. Despite that, there are still a few preserved areas in this region, although they are very small and severely fragmented.
Observations:— Tradescantia schwirkowskiana is morphologically closest to T. crassula (Figs. 5 and 6), from which it differs by the densely-branching stems (even near the apices) and longer internodes, (2.5)–10.0–17.0 cm long vs. internodes with 1.0–5.0 cm in T. crassula. Additionally, T. crassula has a succulent subterraneous rhizomelike basal stems, frequently more than 10 mm wide, which are absent in T. schwirkowskiana, whose basal stems are to 4 mm wide. Tradescantia schwirkowskiana has internodes with a line of multicellular trichomes opposite to leaf insertion, vs. glabrous stems in T. crassula; furthermore, T. schwirkowskiana has membranaceous leaf blades, flat, elliptic to broadly elliptic, with conspicuous midvein and secondary veins on both faces vs. coriaceous to succulent, slightly revolute, elliptic to lanceolate blades, with secondary veins inconspicuous on both sides in T. crassula. The width of the valves of the capsule may also be used to distinguish T. schwirkowskiana, whose fruits have each valve 2 mm wide, while in T. crassula each valve is 3–4 mm wide.
Additional material examined (paratypes): — BRAZIL. SANTA CATARINA: São Bento do Sul: Floresta Ombrófila Mista, 31 December 2013, P. Schwirkowski 197 (FURB 46950).
description: Published as part of Funez, Luís Adriano, Hassemer, Gustavo & Ferreira, João Paulo Ramos, 2016, Description of Tradescantia schwirkowskiana (Commelinaceae), a narrow endemic new species from Santa Catarina, southern Brazil, and typification of T. crassula, pp. 63-72 in Phytotaxa 272 (1) on pages 64-68, DOI: 10.11646/phytotaxa.272.1.3, http://zenodo.org/record/13661345