Besleria brevicalyx G.E.Ferreira & Chautems, 2016

Ferreira, Gabriel E., Costa, Idimá G., Araujo, Andréa O., Hopkins, Michael G. & Chautems, Alain, 2016, Three new species of Besleria (Gesneriaceae) from the southeastern Brazilian Atlantic rainforest, Phytotaxa 263 (3), pp. 270-278 : 272-274

Besleria brevicalyx G.E.Ferreira & Chautems , sp. nov. ( Fig. 2 )

Besleria brevicalyx resembles B. macahensis in its short calyx, adherent to the corolla base, however, it differs by its 3-verticillate leaves (vs. opposite and decussate), longer yellow pedicel and shorter and green-keeled calyx lobes (vs. calyx shorter and purplish).

Type:— BRAZIL. Minas Gerais: Descoberto, Reserva Biológica da Represa do Grama, trilha do Bananal , 9 November 2014, G. E. Ferreira et al. 292 (holotype INPA!; isotypes G!; RB!; HUFABC!) .

Terrestrial shrub, 0.4–1.8 m tall. Stems branched, subterete, up to 0.4 cm diam., brown, glabrous, sericeous when young, internodes up to 3.0 cm long. Leaves 3-verticillate, equal in a whorl; petioles 2.2–4.1 cm long, green, pubescent; leaf blades oblanceolate, 12.0–20.5 × 3.4–5.6 cm, apex attenuate, base long-attenuate, margin distantly serrulate, membranaceous; adaxial surface green, puberulent; abaxial surface pale green, pubescent, 8–10 pairs of secondary veins. Inflorescence axillary, cymose, epedunculate or rarely very short peduncle, with 1–3 flowers per node; pedicels terete, 2.2–3.4 cm long, green, pubescent. Calyx lobes 5, lobes erect, adherent to the corolla base, dorsally keeled, slightly equal, lanceolate, 4–6 × 3–4 mm, apex acute to mucronate, margin entire, yellow-greenish, outside sparsely puberulous-glandular, inside glabrous. Corolla horizontal in relation to calyx, 16–18 mm long, tube contracted at base, limb regular, 6 mm wide at the base, 4 mm wide at the narrowest point, throat 7 mm wide, ventricose, whitishyellow, outside puberulous-glandular, inside glabrous; lobes 5, erect, slightly equal, semiorbicular, 3 × 3 mm, margin entire, white, glabrous. Nectary annular, 0.2 mm wide, glabrous. Stamens 4, included in the throat; filaments 5–7 mm, epipetalous, adnate, free portion of filaments arising at 3 mm from the base of the corolla, glabrous; anthers 1 × 2 mm, longitudinally dehiscent. Ovary ovoid, 3 × 4 mm, puberulous; style included in the throat, 5–6 mm long, puberulous-glandular; stigma bifid, puberulous. Fruit not seen.

Distribution and ecology:— This species occurs in Descoberto, Minas Gerais state ( Fig. 5 ). It was collected in seasonal dry forest, of the Atlantic rainforest domain, occurring on sandy/ rocky banks of streams ( Fig. 4D ) at ca. 550–950 m elevation. Only a few plants were found at each collection point.

Phenology:— Flowers are recorded from January to October.

Conservation status:— Endangered (EN) B1ab(i, iv), according to the IUCN criteria, based on the extent of occurrence estimated to be less than 5,000 km 2 in only two locations ( IUCN 2013).

Taxonomic relationships:— Besleria brevicalyx has characteristics similar to those of B. macahensis Brade (1948: 74) , including fasciculate inflorescence, calyx closely adherent to the corolla base, calyx lobes 3–4 mm wide, and yellowish-white corolla. Howerer, it differs from B. macahensis by its 3-verticillate leaves (vs. opposite), yellow pedicels (vs. purplish-yellow), and yellow calyx with green-keeled calyx lobes (vs. purplish-yellow). Besleria brevicalyx also has longer pedicels and shorter calyx lobes ( Table 1). Additionally, B. brevicalyx occurs in Minas Gerais and Espirito Santo in sandy and rocky substrates in seasonal dry Forest, whereas B. macahensis is restricted to Rio de Janeiro state and occurs in substrates rich in organic matter in the Atlantic rainforest.

Etymology: — The name “brevicalyx ” refers to the very short calyx lobes that are adherent to the corolla base.

Additional specimens examined (paratypes):— BRAZIL. Minas Gerais: Descoberto, Reserva Biológica da Represa do Grama , 18 May 2002, A. V. Lopes et al. 43 ( CESJ!, G!) ; same place, 29 April 2000, C. L. Faria et al. 70 ( CESJ!, G!) .

Figures

FIGURE 2. Besleria brevicalyx. A. Calyx and corolla in lateral view with a close up of the glandular indumentum. B. Corolla in frontal view. C. Pistil and nectary. D. Habit. E. Corolla opened to show stamens (A–E from G.E. Ferreira et al. 292).

FIGURE 4. Morphology and habitat of the new species of Besleria. A–B. Besleria aurea. A. Calyx and corolla in frontal view. B. Calyx and corolla in lateral view. C–D. Besleria brevicalyx. C. Calyx and corolla in frontal view. D. Habit and habitat. E–G. Besleria diabolica. E. Flowering branch. F. Habit. G. Calyx in lateral view. (A–B from I.G. Costa 230; C–D from G.E. Ferreira et al. 292; E from T. Flores s.n., F–G from G.E. Ferreira et al. 271).

FIGURE 5. Distribution of the three new species of Besleria in eastern of Brazil.