Mansoa ivanii M.M.Silva-Castro, 2016

Silva-Castro, Milene Maria Da & Queiroz, Luciano Paganucci De, 2016, Five new species of Mansoa DC. (Bignoniaceae) from South America, Phytotaxa 258 (1), pp. 49-62 : 53-55

Mansoa ivanii M.M.Silva-Castro , sp. nov. ( Figs. 3 A–C ; 4 )

Similar to Mansoa hirsuta Candolle (1845: 182) in its elliptic-obovate, pubescent leaflets, from which it differs by the smaller corollas, with 3.8–4 × 2–2.5 cm (vs. larger corollas, with 4.5–6 × 3–5 cm in M. hirsuta ), 5-laciniate calyx with veins not extended above the lobe apex (vs. 2–3-laciniate calyx with prominent veins in long mucronate lobes in M. hirsuta ), and viscid epidermis of young vegetative and reproductive structures (vs. not viscid epidermis in M. hirsuta ).

Type:— BRAZIL. Bahia: Caetité, 13 July 2008, M. M. Silva-Castro & I. F. Castro 1469 (holotype HUEFS!, isotypes ALCB!, CEPEC!, HRB!, HUESB!, K!, MO!, NY!, MBM!, RB!, SPF!).

Lianas with onion odor; branches viscid, cylindrical to subquadrangular, tomentose, interpetiolar areas with field of patteliform nectaries, bark striated; prophylls of the axillary buds 2–3 mm long, obovate, tomentose. Leaves 2–3- foliolate; petiole 1.5–4 cm long, tomentose; petiolule of the distal leaflet 2.5–3 cm long, petiolules of the lateral leaflets 0.5–1 cm long, tomentose, without indentations or wrinkles; leaflets 3.5–7.2 × 2–5.5 cm, chartaceous, elliptic to orbicular, apex acute to acuminate, margins entire to irregularly dentate, revolute, base cordate to oblique, 3-nerved, concolorous, adaxial surface pubescent, abaxial surface tomentose, patteliform nectaries at the axil of the main veins near the leaflet base; tendrils trifurcate. Thyrses terminal or axillary, congested, multi-flowered, main axis 5–8 cm long, cylindrical, tomentose. Calyx 15–20 × 13–15 mm, green with greenish-purple lobes, coriaceous, cylindrical, lacinia 5, much longer than the calyx tube, 5–7 mm long, venation prominent or not, veins not extended above the lacinia apex, tomentose, without nectaries; corolla 4.1–4.8 × 2.5–2.7 cm, purple, tube greenish-white at the base, membranaceous, tubular-campanulate, externally glabrous at the basal third and pubescent at the mid-apical region, lobes with a slightly emarginate and mucronate apex; stamens slightly exserted, dorsal filaments 2.4–2.9 cm long, ventral filaments 1.8–2 cm long, connective elongated, pubescent, thecae 4–5 mm long; staminode 8–10 mm long; nectariferous disk 0.5–0.7 mm long, 2–2.2 mm diam., annular; ovary 3–3.4 × 1–2 mm, cylindrical, lepidote, 2-series of ovules per locule, style 2.7–3 cm long, stigma 3–4 mm long, lanceolate. Capsule (immature) 21–25 × 1.5–2 cm, linear, flattened, apex acuminate, margins irregularly constricted, base attenuate; valves chartaceous, not striated, not verrucose, tomentose, veins prominent, without ribs; calyx persistent. Seeds not seen.

Distribution: —Recorded only from Seasonally Dry Forests from southwestern Bahia (known locally as Caatinga), Brazil, where it occurs in the municipalities of Brumado and Caetité ( Fig. 2B ).

Phenology: —Flowers and fruits collected in July.

Conservation status:— Mansoa ivanii is assessed as critically endangered (CR) under the criteria B2a, b.iv ( IUCN 2012). This species is known from only three collections from the municipalities of Brumado and Caetité, where it occurs on the margins of the BA 030 state highway, an iron and uranium mining region, with no conservation areas.

Etymology:—The epithet honors the entomologist and illustrator Ivan Farias Castro.

Notes:—The species is characterized by onion odor, viscid young branches and leaflets, congested multi-flowered inflorescences, calyx with long cuspidate lacinia, slightly exserted stamens (with anthers reaching the corolla throat), elongated hairy connective, and linear cylindrical capsules with an acuminate apex.

Mansoa ivanii is morphologically similar to M. hirsuta , a widespread and common species of the Caatinga vegetation of northeastern Brazil; these species occur sympatrically in southwestern Bahia. Both species share densely pubescent young branches and leaflets, but differ by the smaller corollas, with 4.1–4.8 × 2.5–2.7 cm in M. ivanii (vs. longer corollas with 7–7.4 × 4–6 cm in M. hirsuta ), calyx with five cuspidate lacinia, with veins not extending beyond the apex (vs. calyces with 2–3 acuminate lacinia, without protruding veins). Mansoa hirsuta is well-known by its strong garlic odor, typical of Mansoa , whereas M. ivanii has an onion-like odor ( Table 1).

The 5-laciniate calyx with elongated lobes of M. ivanii is similar to that found in M. minensis . It differs from that species by a wider corolla throat, corolla lobes with a slightly emarginate and mucronate apex (vs. corolla lobes with acuminate apex in M. minensis ), and slightly exserted stamens (vs. included stamens in M. minensis ). Moreover, M. ivanii has an onion-like odor, whereas M. minensis has the garlic odor, typical of the genus Mansoa ( Table 1).

Additional specimens examined (paratypes):— BRAZIL. Bahia: Brumado , rodovia BA 030, 10 km W de Brumado, 17 June 1986, G. Hatschbach & J. M. Silva 50441 (C, MBM, MO) ; Ibitira , rodovia BA 030, 17 June 1986, G. Hatschbach & F. J. Zelma 50452 (C, MBM, MO) .

Figures

FIGURE 2. Distribution range of the newly described species of Mansoa. A. Mansoa gentryi. B. Mansoa ivanii. C. Mansoa longicalyx. D. Mansoa minensis. E. Mansoa paganuccii.

FIGURE 3. Mansoa ivanii. A. detail of the calyx. B. flower. C. capsule. M. minensis. D. detail of the calyx. E. corolla. M. paganuccii. F. detail of the calyx. G. corolla. H. capsule. (Photos by MMSC).

FIGURE 4. Mansoa ivanii. A. flowering branch. B. leaflets showing morphological variation. C. leaf showing the trifurcate tendril. D. calyx. E. open corolla with slightly exserted androecium. F. nectariferous disk and pistil. G. ovary cross-section showing 2-series of ovules per locule. H. capsule. (Drawn by Ivan Farias Castro; from M. M. Silva-Castro & I. F. Castro 1469).