Typus: Brazil. Bahia: Guaratinga, Corrego Jacutinga, 16°38′26″S 39°47′54.4″W, 370 m, 23.IV.2009, (fl., fr.), L. Kollmann, A. P. Fontana, E. Leme & C. Esgario 11571 (holo-: MBML; iso-: RB, CEPEC, NY).

Species haec B. novalombardiensi, cui affinis, sed plantis minoribus, foliis late ovatis indumento lanuginoso et inflorescentia majore; a B. aguiabrancensi, proxima, sed plantis majoribus, indumento foliorum lanugino, stipula decidua et inflorescentia majore; a B. umbraculiferae, affinis, sed foliis late ovatis indumento lanuginoso et floribus masculinis tepalis quaternis; a B. fellererianae, affinis, sed plantis majoribus et floribus masculinis tepalis quaternis differt.

Suffrutescent herb 0.8–1.2 m tall, rupicolous to saxicolous, stellate trichomes on all parts except both sides of the inner tepals of the staminate flower and the inner surface of all other tepals. Stems 0.85–1.2(-2) cm in diameter, green, the older ones brown, internodes (0.5-)1.5–8 cm long, glabrescent, lenticels present. Stipules 2.5–3.5 × 0.5–0.9 cm, green, lanceolate to narrowly ovate, deciduous, slightly asymmetrical, apex acute, margins entire. Leaves alternate. Petioles 4.2–17.5 × 0.26–0.3 cm, green to reddish. Lamina 10–18.8 × 6.5–13 cm, green with whitish stellate trichomes, adaxial face glabrescent, shining when older, abaxial surface green covered by whitish indument, peltate, simple, asymmetrical, transversely ovate, apex obtuse to acute, base orbiculate, margins revolute, sinuate, hydathodes present, venation actinodromous, veins 9–10 at base, stomata in groups, upper epidermis multi-layered. Inflorescence 32.5–61 cm long, dichasium, 5–6-times dichotomous, red when mature, bracts greenish, deciduous, soon falling, 3.5–16 × 2.7–7 mm. Staminate flower, pedicels 4–6 mm long, reddish; tepals four, the outer 0.7–1.1 × 0.6–0.7 cm, white, reddish base, obovate to orbicular, rounded apex, the inner 4–5 × 2 mm, white, oblong to obovate, concave, glabrous, apex obtuse; stamens 24–42, yellow, on a short column, filaments 0.5–2 mm long, anthers ca. 1 mm long, rimose, ovate to oblong, apex obtuse to rounded, the connective projecting. Pistillate flower, pedicels 0.75–1.63 cm long, red; prophylls 2, inserted on apex pedicel, 5–7.4 × 3–5.5 mm, white, ovate to orbiculate, deciduous, apex obtuse to rounded, margins entire to erose; tepals five, 5.5–10 × 3.5–6 mm, white, base reddish, unequal, obovate, apex obtuse; style three, 2.8–4.5 mm long, yellow, reddish at base, trifid, bifurcate, united at base, style branches spirally twisted, with band of stigmatic papillae, the rest of the style with minute papillae, occasionally stigmatic papillae covering entire surface of style branches. Ovary 3-locular, placentation axial, one placenta per locule, ovules on both sides of the placenta. Capsules ca. 7.5 × 4.5 mm, white to reddish, basally dehiscent, chartaceous and opaque when dry, wings three, ascending, rounded, larger wing 9.7–16 × 5–8 mm, smaller wings 7.3–1.1 × 2–4 mm, stigma persistent when dry. Seeds ca. 0.4 × 0.2 mm when dry, cylindrical, oblong, apex obtuse.

Etymology. — The epithet is a posthumous tribute to Jack Golding, who has greatly contributed to the knowledge of Begoniaceae.

Ecology and geographical distribution. — Begonia goldingiana was found growing in leaf litter and humus on inselbergs in Itamaraju county in association with B. lossiae L. Kollmann, B. reniformis Dryand., Alcantarea sp. (Bromeliaceae), Stillingia sp. (Euphorbiaceae) and Tibouchina sp. (Melastomataceae). It was also found growing in low canopy forest on sandy soil on a granitic formation, in association with Anthurium sp. and Philodendron sp. (Araceae), Cryptanthus sp., Hohenbergia sp., Neoregelia sp. (Bromeliaceae), Pseudo bombax sp. (Malvaceae), Smilax sp. (Smilacaceae) and Syagrus sp. (Arecaceae).

Discussion. — Within Begonia sect. Pritzelia, B. goldingiana L. Kollmann & A. P. Fontana most closely resembles B. umbraculifera Hook. due to its suffrutescent habit, peltate leaves, inflorescence size and having undivided placentae. Nevertheless, it can be distinguished by having an indument of stellate trichomes (vs. glabrous), obovate leaves (vs. orbiculate), entire leaf margins (vs. denticulate), auricules not present on the abaxial face of the leaf (vs. present), unisexual flowers (vs. unisexual and bisexual flowers) (bisexual flowers were reported by the author of B. umbraculifera from cultivated material) and staminate flowers with four tepals (vs. two tepals).

Begonia goldingiana also resembles B. fellereriana Irmsch. which has peltate leaves and undivided placentae. Nevertheless, the new species can be distinguished by being a suffrutescent (vs. rhizomatous) herb, by having longer petiole (4.2–17.5 vs. 1.5–2.5 cm), obovate leaves (vs. suborbiculate), larger leaves (10–18.8 × 6.5–13 vs. 5 × 4.5 cm) and staminate flowers with four tepals (vs. two tepals). Begonia goldingiana also resembles B. novalombardiensis L. Kollmann and B. aguiabrancensis L. Kollmann. These latter two taxa are endemic to Espírito Santo State, and share with B. goldingiana a suffrutescent habit, peltate leaves, stellate trichomes and undivided placentae. However, the new species can be distinguished from B. novalombardiensis by its size (0.8–1.2 vs. 1.5–2 m high), leaf shape (broadly ovate vs. narrowly ovate), adaxial surface of leaves glabrescent (vs. persistent trichomes), leaf indument (flattened stellate trichomes vs. erect) and inflorescence size (32–45 vs. 10–25 cm long). Begonia goldingiana differs from B. aguiabrancensis, by its size (0.8–1.2 vs. 0.4 m high), leaf size (10–17 vs. 6.5–8.5 cm long), adaxial surface of leaves glabrescent (vs. persistent trichomes), leaf indument (flattened stellate trichomes vs. erect), deciduous stipules (vs. persistent) and by its inflorescence size (32–45 vs. 18–36 cm long). Finally, B. goldingiana resembles B. lealii Brade and to B. ibitiocensis E. L. Jacques & Mamede by its stellate trichomes and peltate leaves. However, neither of these taxa are classified in sect. Pritzelia since they have bifid rather than entire placentae.

Conservation. — Due to the apparent endemic distribution of Begonia goldingiana in the Atlantic Forest of Southern Bahia with an extent estimated to be less than 500 km² (B2), a habitat that is severely fragmented (B2a), and with continuing decline observed in area, extent, and quality of suitable habitat (B2b(iii)), this new species should be considered at least an endangered species (EN) (IUCN, 2001).

Additional specimens examined. — Brazil. Bahia: Itamaraju, Monte Pescoço, Fazenda Novo Horizonte, track to Colina, Prop. Sr. Carlos Mascarenhas, Atlantic Forest, 16°59′43.4″S 39°35′26.4″W, 464 m, 10.X.2007, fl. and fr., A. P. Fontana & K. A. Brahim 4145 (MBML, RB); Itamaraju, Monte Pescoço, Fazenda Novo Horizonte, 16°59′8.3″S 39°34′38.4″W, 125 m, 20.IV.2009, fl., L. Kollmann, A. P. Fontana, E. Leme & C. Esgario 11544 (MBML); Itamaraju, Fazenda Pau-Brasil, ca. 5 km a NW de Itamaraju, 19.IX.1978, fl., S. Mori, L. A. Mattos Silva & T. S. dos Santos s.n. (CEPEC, RB); Itamaraju, Fazenda Pau-Brasil, Monte Pescoço, afloramento rochoso, 250 m, 9.IV.1996, fl., G. Martinelli, S. Porembski & M. Leitman 14831 (RB).