Streptocarpus ibityensis Humbert

Macmaster, Gwyneth, Möller, Michael, Hughes, Mark, Edwards, Trevor J. & Bellstedt, Dirk U., 2005, A new species of Streptocarpus (Gesneriaceae) endemic to Madagascar, Adansonia (3) 27 (1), pp. 131-136 : 135-136

Streptocarpus ibityensis Humbert

TYPUS. — Perrier de la Bâthie 8522, Madagascar, Centre (pentes occidentales), Mont Ibity, sud d’Antsirabe, 1 900-2 300 m (holo-, P).

Rosulate perennial herb. Leaves 29-68 × 9-27 mm, oblanceolate with rounded apex or lanceolate-elliptic acute apex, base attenuate-acute, slightly asymmetric, margin crenate-subdentate, upper and lower surfaces covered in laterally compressed hairs c. 2 mm long, sometimes obscuring the alternate venation. Inflorescences 1-6; peduncles slender, 53-80 mm long, minutely pubescent, hairs sometimes glandular; pedicels slender, 4- 11 mm, pubescent, sometimes densely so, with occasional minute glandular hairs. Calyx segments divided to base, 1.1-2.0 × 0.5-1.0 mm, pubescent, glandular hairs outside. Corolla 7-9 mm long, pouch-shaped, white at base with pale lilac stripes on the outside of the tube, lobes white to pale lilac; tube 4.3-6.1 mm long, 2.8-3.8 mm diameter at widest point, 1.9-3.0 mm at mouth, minutely pubescent outside, glabrous inside, upper lip consisting of two lobes 1.2-4.0 × 0.7-5.0 mm; lower lip consisting of three lobes, median lobe 2.5-4.0 × 3.0-4.0 mm, laterals 2.4-3.0 × 2.5-3.0 mm. Stamens arising from the base of the corolla tube; filaments 3.0- 4.1 mm, slender, glabrous; anthers basifixed, extrorse; posterior staminode smaller than laterals. Ovary 1.5-2.3 mm with minute glandular hairs; style 3-4 mm, glabrous, pale to deep pink; stigma capitate, papillate. Capsule 6-10 mm with minute glandular hairs.Seeds c. 0.5 mm, elliptic, seed coat slightly verruculose. — Fig. 3.

DISTRIBUTION AND ECOLOGY. — Endemic to Mount Ibity, central Madagascar. Occurring at altitudes of up to 1750 m, growing under boulders and in caves. Flowering period March-May.

MATERIAL EXAMINED. — MADAGASCAR. Clement et al. 1547, Ibity sud, May 1971 ( E); Möller 9722, Antananarive Prov. , north side on plateau of

mountain, 19°10’S, 47°28’E, 1700 m, May 1997 ( E) ; Dorr 3863, Mt Ibity (sud), Mar. 1985 ( E) ; Clement et al. 2144, north end of Mt Ibity, 27 km west of Antsirabe , 20°05’30”S, 47°00’00”E, open slopes with Uapaca bojeri woodland, Apr. 1992 ( E) ; Möller 01-32, north facing slope of Rasters Peak on Mt Ibity , 20°03’48.8”S, 47°00’31.4”E, 1730 m, Mar. 2002 ( E) ; Möller s. n., cultivated material grown from seed taken from Möller 01-32 and cultivated at the Royal Botanic Garden Edinburgh ( E, spirit collection, accession No. 20020521) .

Figures

FIG. 3. — Streptocarpus ibityensis Humbert: A, whole plant; B, flower side view; C, flower front view; D, dissected flower. Drawing by Christina OLIVER.