Begonia wasshauseniana L. Kollmann & Peixoto, 2012

Kollmann, Ludovic Jean-Charles & Peixoto, Ariane Luna, 2012, Begonia fragae L. Kollmann & Peixoto and Begonia wasshauseniana L. Kollmann & Peixoto (Begoniaceae), two new species from the state of Espírito Santo, Brazil, Candollea 67 (1), pp. 59-64 : 63-64

2. Begonia wasshauseniana L. Kollmann & Peixoto , spec. nova ( Fig. 2 ).

Typus: BRAZIL. Espírito Santo: Águia Branca, Santa Luzia, Propriedade de Ciro Ferreira , 180-300 m, 18°59’9”S 40°40’6”W [flowering in cultivation at Mello Leitão Biological Museum greenhouse], 30.XII.2008, L. Kollmann 11348, fl. fr. (holo-: MBML!).

Species haec Begonia ruschii affinis, sed plantae majoribus, foliis statura, floribus pistillatis 2-prophyllum et fructus minoribus differt.

Suffrutescent herb 1.5-2 m tall, rupicolous to saxicolous, peltate trichomes, ca. 0.1 mm in diam. Stems 0.7-1.1 cm in diameter, brown to reddish, ferruginous trichomes, grey when dry, stem striate when dry, internodes 1-14 cm long. Stipules 8-9 × 3-3.5 mm, ferruginous, asymmetrical, falcate, deciduous, apex acute, stellate trichomes on abaxial face. Leaves alternate. Petioles 0.8-3.5 cm, reddish, peltate trichomes. Lamina 8-11.2 × 3.2- 5.2 cm, adaxial face glossy, dark green; abaxial surface light green with grey stellate trichomes, simple, asymmetrical, transversely ovate to obovate, apex acuminate, base cordate, margins entire to crenulate with hydhatodes, venation actinodromous, veins 5-7, reddish abaxially, stomata in groups (clustered), multiple upper epidermis. Inflorescence 15-25 cm long, reddish, dichasium, five dichotomous cymes, grey peltate trichome when dry, bracts white-greenish with ferruginous trichomes, 0.4-1 × 0.15-0.5 cm flattened, ovate, falcate, concave, deciduous, apex obtuse. Staminate flower: pedicels ca. 6 mm long, pinkish with ferruginous trichomes; 2-prophylls in the first open staminate flower, ca. 7 × 5 mm, obovate, apex rounded, abaxial face with trichomes; 2-sepals, 4.5-6 × 3-4 mm, white, obovate, apex rounded, abaxial face with trichomes, 2-petals, 3-4.5 × 1.5- 2.5 mm, white, obovate, apex rounded, glabrous; stamens ca. 25, yellow, filaments fused in a short column, 1-1.7 mm long, the filaments 0.5-1 mm long, the anthers 0.5-0.7 mm long, obovate, the connective lightly projecting, apex obtuse. Pistillate flower: pedicels 4-5.5 mm long, stellate trichomes; 2-sepals, white, 4.5 × 3-3.5 mm, elliptic, apex obtuse, stellate trichomes on abaxial face; 3-petals, white, 2.5-3.8 × 1.6-3 mm, unequal, elliptic to obovate, apex obtuse to rounded, stellate trichomes on abaxial face; style three, 1.3-1.5 mm long, yellow, bifurcate, united at base, spirally twisted, with bands of stigmatic papillae on the branches, glandulate papillae. Ovary 3-locular, placentation axile, one placenta per locule, ovules on both sides of placenta. Capsules 3-5 × 3-4.5 mm, white, basally dehiscent, 3-wings, 3.5-4 × 1-1.3 mm sub-equals, rounded. Seeds ca. 0.4 × 0.2 mm, cylindrical, oblong.

Taxonomy. – Begonia wasshauseniana has a compact inflorescence with the flowers touching each other when young but at inflorescence maturity the flowers are not in contact anymore, as B. ruschii L. Kollmann. The first staminate flower, in the middle of the first dichasium, has 2 prophylls in the apex of the pedicel, the other flowers do not have any prophylls.

This new species should be classified in sect. Pritzelia (Klotzsch) A. DC. due to the presence of one placenta per locule with ovules on both sides of the placenta and anther connectives extended.

Relationships. – Begonia wasshauseniana resembles B. ruschii , an endemic species from Espírito Santo state, by its suffrutescent habit, stellate trichomes, form of stipules, tepals, stamens and stigmas, and entire placenta. Nevertheless, it can be distinguished from B. ruschii by larger habit (1.5-3 m vs. 0.5- 1.5 m), leaf size (8-11 × 3-5 cm vs. 6.5-18 × 4.5-10 cm), 2-prophylls in the first staminate flower only (vs. 2-prophylls in the base of the ovary); fruit smaller (0.6 × 0.6-0.7 cm vs. 0.6-1.2 × 1.1-1.6 cm). Begonia wasshauseniana resembles B. albidula Brade and B. kuhlmannii Brade , two endemic species from Espírito Santo, by the suffrutescent habit, rupicolous to saxicolous, leaves tranversely ovate, adaxial face glossy green. Nevertheless, it can be distinguished from them by its entire placenta (vs. placenta bifurcate), 2-prophylls on the first staminate flower (vs. 2-prophylls in the base of the ovary) ( Table 2 ).

Etymology. – The epithet of this new species honors Dieter Carl Wasshausen for his outstanding contributions to the knowledge of Begoniaceae .

Distribution and ecology. – Begonia wasshauseniana grows in leaf litter and humus on rocks in sub-montane dense ombrophilous forest within inselberg habitats of the Atlantic Forest at 100- 300 m. Flowers have been collected in December; fruits in April.

Conservation status. – Due to the apparent endemic distribution of B. wasshauseniana , with extent of the occurrence estimated to be less than 10 km 2, habitat severely fragmented and continuing decline of the area, extent and quality of habitat, it seems prudent to include this species in the Critically Endangered species list (CR) (B2ab(iii)) according to the criteria of the IUCN (2001).

Paratypus. – BRAZIL. Espírito Santo: Águia Branca, Santa Luzia, Propriedade de Ciro Ferreira , 18°59’9”S, 40°40’16”W, 180- 300 m, 4.IV.2007, V. Demuner & al. 3550, fr. ( MBML!, NY!, P!, RB!, SP!, VIES!) .

Figures

Fig. 2. – Begonia wasshauseniana L. Kollmann & Peixoto. A. Habit; B. Stipule flattened, front view; C. Bract; D. Prophyll flattened, front view; E. Staminate flower, sepals (1), petals (2); F. Stamen; G. Fruit; H. Pistillate flower, sepals (1), petals (2); I. Styles, above dorsal view, below ventral view; J. Seed. [V. Demuner & al. 3550] [Drawn by L. J.-C. Kollmann]