Begonia trevisoensis J.C. Jaramillo, 2018

Jaramillo, Julio C., Kollmann, Ludovic Jean Charles & Fiaschi, Pedro, 2018, Begonia trevisoensis, a new species of Begonia sect. Pritzelia (Begoniaceae) from Santa Catarina State, Brazil, Phytotaxa 381 (1), pp. 51-57 : 52-55

Begonia trevisoensis J.C. Jaramillo , sp. nov. ( Figs. 1 − 4 )

This species differs from B. itatinensis by leaf blades 49−65 × 10−15 mm [vs. 10−30(−43) × 5−10 mm], with serrate (vs. deeply serrate) margins, and elliptical (vs. narrowly triangular) stipules 12−22 × 2.5−5 mm (vs. 4−10 × 0.8−2 mm).

Type:— BRAZIL. Santa Catarina: Treviso, Brasília , 28°26’37.09’’S, 49°29’55.04’’W, 572 m, 24 November 2009 (fl. and fr.), J. L. Schmitt et al. 698 (holotype FURB 15200 !; isotype RB 00593215 !) .

Decumbent or scandent subshrubs 0,4 − 1 m high. Stem 0.5 − 1.5 mm diam., internodes 1 − 2(− 3.5) cm long, slightly lignified at base, with sparse appressed trichomes. Stipules 11 − 22 × 2.5 − 6 mm, narrowly elliptic to lanceolate, the margin entire, the apex acuminate, mucronate, membranaceous when dry. Petioles 1 − 4.5 mm long, green, with sparse appressed trichomes ca. 0.5 mm long. Leaf blades 4.9 − 6.5 × 1 − 1.5 cm, oblanceolate to elliptic, symmetric or slightly asymmetric at base, green, the base attenuate, the margin serrate, the apex acuminate, venation simple craspedodromous, adaxially glabrous, with appressed trichomes along main vein when young, abaxially with sparse appressed trichomes along main and secondary veins. Inflorescence axillary, with one flower at a time, first staminate, then pistillate, the peduncle 2.5 − 4.5 cm long, with sparse multicellular trichomes; bracts 2, 5 − 6 × 0.5 mm, lanceolate, glabrous, persistent. Staminate flowers with the pedicel 4 − 6 mm long, with sparse multicellular trichomes; outer tepals 2, ca. 8 × 6 mm, white, obovate to widely elliptic, the margin entire, the apex rounded, abaxially with sparse trichomes in the mid to basal portion; inner tepals 2, ca. 6 × 2.5 mm, white, oblanceolate, the margin entire, the apex rounded, abaxially glabrous; stamens 8 − 9, anthers ca. 2 × 0.5 mm, yellow, narrowly oblong, connective slightly projected, the apex obtuse to rounded. Pistillate flowers with the pedicel 4 − 5 mm long, with sparse multicellular trichomes; bracts 2, 1 − 2 × 0.5 − 1 mm; tepals 5, 5 − 10 × 1.5 − 3.5 mm, white, elliptic, the apex acute to acuminate, mucronate, sometimes slightly denticulate, glabrous; ovary 3-locular, placentation axile, one placenta per locule, ovules on both sides of the placentae; styles 3, ca. 3 mm long, yellow, each bifurcate, spirally covered with stigmatic papillae. Capsules with the pedicel 5 − 6 mm long; ca. 6 × 1.5 − 2.5 mm, with 3 sub-equal wings, wings 10 − 16 × 5 − 7 mm, straight to slightly ascending, obtriangular, the apex acute to obtuse, glabrous. Seeds 0.4 − 0.5 mm, oblong, the apex rounded.

Distribution and ecology: — Begonia trevisoensis is only known from the locality of Brasília, in the municipality of Treviso, Santa Catarina. It has been found growing as an epiphyte or is rupicolous in relative well-preserved hygrophilous Atlantic Forest, varying from 555 − 575 m in elevation ( Fig. 4 ).

Etymology: —The specific epithet honors the municipality of Treviso, where the new species has been collected so far.

Conservation status: — Begonia trevisoensis is known from a single locality. Before more intensive fieldwork is carried out in the region, we prefer to regard it as Data Deficient (DD) according to the IUCN categories and criteria (2012).

Taxonomic comments: — Begonia trevisoensis resembles B. itatinensis Irmsch. ex Brade (1944: 15) because both are subshrubs ( Figs. 2A , 3A ), with symmetric or slightly asymmetric leaf blades at the base ( Fig. 2B ) and inflorescences with one flower at a time ( Figs. 2A , 3B − C ). However, B. trevisoensis differs from B. itatinensis by its larger leaf blades 49 − 65 × 10 − 15 mm [vs. 10 − 30(− 43) × 5 − 10 mm], with serrate margins (vs. deeply serrate), and its elliptical (vs. narrowly triangular) stipules, reaching 12 − 22 × 2.5 − 5 mm (vs. 4 − 10 × 0.8 − 2 mm). It also resembles B. polyandra Irmsch. (1953: 43) due to similar size and shape of its leaves, but B. trevisoensis can be easily distinguished by its one-flowered inflorescences (vs. multi-flowered inflorescences), its elliptic (vs. narrowly triangular) stipules reaching 12 − 22 × 2.5 − 5 mm (vs. 5 − 11 × 2 − 2.5 mm). Moreover, while B. trevisoensis is endemic from Treviso, in Southeastern Santa Catarina, B. polyandra is only known from the states of São Paulo, Paraná and Northern Santa Catarina.

According to its morphological characteristics, including its female flowers with 4 or more perianth segments, its 3-locular ovary with a single placental branch per locule and ellipsoid seeds, 1.7 − 2.6 times as long as broad, Begonia trevisoensis can be assigned to Begonia sect. Pritzelia (Klotzsch) A. DC. , the largest and most morphologically variable section of Neotropical Begonia , whose species are predominantly found in extra-Amazonian Brazil ( Doorenbos et al. 1998, Moonlight et al. 2018).

Paratype: — BRAZIL. Santa Catarina: Treviso, Nova Brasília, 28°26’37’’S, 49°29’55’’W, 555 m, 30 January 2010 (fr.), M. Verdi et al. 3510 (CNMT 4316, FURB 15368!, RB 01366096!).

Figures

FIGURE 1. Holotype of Begonia trevisoensis (J.L. Schmitt et al. 698, FURB).

FIGURE 2. Begonia trevisoensis. A. Single flowering branch; B. Leaf upper surface; C. Branch whit stipules; D. Stipules, abaxial view; E. Male flower, oblique view; F. Pistillate flower, frontal view; G. Fruit, side view (based on J.L. Schmitt et al. 698). Illustrations by Leandro Lopez de Souza.

FIGURE 3. Begonia trevisoensis. A. Habit. B. Pistillate flower, frontal view. C. Branch with flower in side view. D. Petiole with sparse appressed trichomes. E. Seeds in side view. Photos A–C by J.L. Schmitt. Photos D–E by J.C. Jaramillo.

FIGURE 4. Distribution map of Begonia trevisoensis (black circle).