Begonia littoralis M. D. Miranda & E. L. Jacques. A. Habitat 2023, sp. nov.
Creators: name: Miranda, Marcelo Dias
name: Jacques, Eliane De Lima
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Cucurbitales
Begoniaceae
Begonia
Begonia littoralis

description: Begonia littoralis M.D.Miranda & E.L.Jacques, sp. nov. (Figs. 1, 2, 3)
Type: — BRAZIL. S„o Paulo: Município de Ubatuba, Camburi das Pedras, estrada para Praia do Camburi, sobre pedras na cachoeira, 23° 21’ 43” S, 44° 46’ 20” W, elevation ca. 145 m, 11 April 2020, M.D. Miranda & M.R. Miranda 208 (holotype: RBR [RBR00055572]!).
Begonia littoralis is most similar to Begonia erythrobracteata M.D.Miranda & E.L. Jacques (2020: 223) but differs in having a whitish green abaxial leaf surface with microscopic glandular trichomes, veins impressed (vs. abaxially vinaceous to light green on the veins, with 2-branched trichomes and fimbriate scales on the principal veins, veins prominent), petiole lanose, with flattened fimbriate scales, intertwined filiform apex, hairs coppery (vs. squamulose with non flat scales, fimbriate apex, hairs whitish), largest capsule wing 14–16 × 14–16(–20) mm, apex descendant, glabrous margin (vs. ca. 14 × 10–12 mm, apex slightly ascendant, margin with trichomes), and an external pair of staminate tepals with short microscopic glandular trichomes (vs. villous, with simple trichomes in the upper third, near the margins, hairs reddish).
Description: —Creeping rhizomatous herb, 30−38 cm tall (excluding the inflorescence). Stem long creeping, reaching up to 23−30 cm, cylindrical, internodes 2−6 cm long, ca. 8−10 mm diam., lenticellate, reddish, lanose, with flattened fimbriate scales along the entire length, intertwined filiform apex, trichomes ca. 2.5 mm long, hairs coppery. Stipules persistent, 1.4−1.6 × 1.2−1.3 cm, triangular-ovate to ovate, apex acute, margins entire, ciliate, dorsal surface pilose throughout, trichomes villous, with an intertwined filiform apex, red or greenish. Leaves simple, petioles (13–)26–28(–36) cm long, 9−10 mm diam., cylindrical, red, lanose, flattened fimbriate scales with an intertwined filiform apex, hairs dense and white when young, becoming more scattered and coppery at maturity, ca. 6 mm long, leaf blades basifixed, ca. 13× 10 cm, cordiform, asymmetrical, chartaceous, apex acuminate, base cordate, basal lobes overlapping the petiole, margins slightly crenulate-dentate, revolute, ciliate, hairs reddish, adaxial surface glabrous, dark green, light green on the veins, white at the insertion of the petiole, veins and petiole insertion prominent, abaxial surface with short microscopic glandular trichomes, white green, veins impressed, venation actinodromous, primary veins 9−12. Inflorescences 4-branched cymes, ca. 11.5 cm long (including the rachis), up to 21 cm long when fruiting, rachis ca. 5.2 cm long (up to 12.5 cm long when fruiting), vilose, reddish. Bracts caducous, 6–7 × ca. 4 mm, ovate, apex acuminate, margins entire, glabrous. Staminate flower pedicels 10–20 mm long, white to reddish, microscopically pubescent with glandular trichomes, tepals 4, external pair (10–)18–19 × (16–) 18–23 mm, reniform, depressed ovate, apex rounded, margins entire, white to pinkish, abaxial surface with short microscopic glandular trichomes, internal pair (4–5)11–12 × (1.7–2.5) 4–5 mm, elliptic to obovate, apex mucronulate to acute, margins entire, white, membranaceous, glabrous, stamens 30–40, ca. 5 mm long, filaments 0.7–1 mm long, free, connective projecting, obtuse, anthers ca. 3 mm long (including connective), oblong, extrorse, yellow. Pistillate flower pedicels ca. 10 mm long, red, with sparse microscopic glandular trichomes, bracteole 1(–2), persistent, spaced from the base of the ovary, ovate to linear, 2.8–3.5 × 0.5 mm, pale green, tepals 5, white to pinkish, subequal, 14–16 × 11–14 mm, ovate to widely ovate, apex retuse, base acute, margins entire or with glandular trichomes to ciliate, membranaceous, with sparse microscopic glandular trichomes, ovary 3-locular, ca. 10 × 15 mm (including wings), with sparse microscopic glandular trichomes, wings unequal, largest one ca. 9 mm wide, two smallest ca. 3 mm wide, flat, with sparse microscopic glandular trichomes, white to pinkish, placentae entire, stigmas 3, ca. 2–5 mm long, bifurcate, branches spiraled, yellow. Capsule 17–23 × 28–35 mm (including wings), ellipsoid, dehiscent in basal portion, with sparse microscopic glandular trichomes, vinaceous to reddish-green when fresh, light brown when mature, peduncles 1.9–2.1 cm long, microscopic glandular trichomes, wings 3, unequal, the largest 14–16 × 14–16(–20) mm, apex descendant, the smallest one 11–12 × 4–5 mm, apex rounded, locular region 7–8 × ca. 6 mm, elliptic to ovate, seeds oblong.
Etymology: —The specific epithet refers to the habitat of the new species, which occurs near the shore of Ubatuba.
Phenology: —Flowering and fruiting from April to July.
Distribution and ecology: — Begonia littoralis is endemic to S„o Paulo State, found in the Municipality of Ubatuba. The species has been collected in the Picinguaba Nucleus of the Serra do Mar State Park in the hydrographic basin of Rio da Fazenda and Córrego das Duas Irm„s, next to Camburi das Pedras beach. It grows on the slopes near the ocean, in submontane ombrophilous forest, at elevations between 50 and 200 m asl. This species is rupicolous, ombrophilous and hygrophilous, thrives in very humid places, usually close to waterfalls, covering rocks on riverbanks. Mizue Kirizawa informed us that the collection SP004345 from Ubatuba, Picinguaba nucleus, was from a hillside forest, in the shade, forming a carpet; the other collection from Ubatuba, in the Núcleo Picinguaba Reserve (SP004344), was from a humid hillside forest, on a trail that goes up the slope of the Atlantic Forest, on a boulder.
Provisional conservation assessment: — Begonia littoralis has been collected inside the protected area of Serra do Mar State Park, one of the localities is very close to the road used to access Camburi das Pedras beach, which is constantly visited by tourists in the summer, and the surrounding area has residential property, because of that, future maintenance of the road and arrival of invasive species may be a threat at some point. We consider a category of Endangered EN B2ab (ii, iii) as appropriate under IUCN Red List criteria (IUCN Standards and Petitions Committee, 2022).
Additional specimens examined (paratype): — BRAZIL. S „o Paulo: Ubatuba, Camburi das Pedras, estrada para a Praia do Camburi, 12 October 2021, M. R. Miranda 202 & M. D. Miranda (RBR00057497!); Parque Estadual da Serra do Mar, Núcleo Picinguaba, 23 May 1989, M. Kirizawa & J.A. Corrêa 2175 (SP [SP004345]!), ibidem, 30 June 1990, M. Kirizawa & J.A. Corrêa 2311 (SP [SP004344]!).
Taxonomic notes:— Gomes da Silva (1988) in her study of the Begoniaceae for the Atlantic Forest of the state of S„o Paulo included a species with similarities to Begonia fluminensis Brade (1945: 30), based on two collections from Ubatuba, state of S„o Paulo and deposited in the SP herbarium. This position is repeated in Gomes da Silva & Mamede (2001). The taxonomic study of Begoniaceae of the Flora of S„o Paulo (Mamede et al. 2012) included the same taxon as Begonia sp. 1, here recognised as Begonia littoralis. B. littoralis is similar to B. erythrobracteata and B. fluminensis which share similar leaf blades, all of them being glabrous adaxially. The comparison of the new species with these two species is presented in Table 1.
Begonia littoralis when compared with other Begonia species from the North Coast of S„o Paulo State, is the only one that possesses an ellipsoid capsule with the apex of the largest wing strongly descendant. Other species that can be found in the region where B. litorralis occurs include the recently described B. lorenzii E.L. Jacques, B. mamedeana E.L. Jacques & S.J. Gomes da Silva and B. margaretiana Handro ex. L. Kollmann. Begonia mamedeana being the species that occupies the same geographical area of our species. Also occurring in the same region are Begonia caraguatatubensis Brade, B. erythrobracteata M.D. Miranda & E.L. Jacques, B. fruticosa (Klotzsch ex. Klotzsch) A.DC., B. hookeriana Gardner, B. itatinensis Irmsch. ex. Brade, B. luxurians Scheidw. and B. stenophylla A.DC., none of them has a descendant apex of the largest wing. We place the new species in Begonia sect. Pritzelia, based on its similarity to other species in the section.
description: Published as part of Miranda, Marcelo Dias & Jacques, Eliane De Lima, 2023, Begonia littoralis (Begoniaceae), a new species from North Coast of São Paulo State, Brazil, pp. 131-137 in Phytotaxa 609 (2) on pages 131-137, DOI: 10.11646/phytotaxa.609.2.5, http://zenodo.org/record/8272314