Impatiens otto-eleonorae Eb.Fischer & Rahelivololona, 2015

Fischer, Eberhard & Rahelivololona, Marie Elisette, 2015, New taxa of Impatiens (Balsaminaceae) from Madagascar VI. Impatiens otto-eleonorae, a new species from Masoala Peninsula, and notes on the taxonomic relationships of Impatiens firmula and I. hildebrandtii, Phytotaxa 217 (2), pp. 155-163 : 155-158

Impatiens otto-eleonorae Eb.Fischer & Rahelivololona , sp. nov. ( Fig. 1 , 2 )

Impatienti hildebrandtii affinis sed habitu valde majore, foliis majoribus margine appendicis distinctis, inflorescentiis cum 2–5 floribus et floribus valde majoribus differt.

Type: — MADAGASCAR. Masola National Park , E slope of Ambohitsitondroinan’Mahalevona, ESE of village of Mahalevona, 15°26’13’’S 049°57’26’’E, 23 February 2003, alt. 1140 m, P.P.Lowry II, G.E.Schatz & J.R.Be 6133 (holotype TAN!; isotypes P!, MO!) .

Perennial herb, erect, glabrous. Stems succulent, green, up to 100 cm tall. Leaves alternate, dark green, shining, 12–17 cm long, petiole 10–20 mm long, with 1–2 pairs of extrafloral nectaries near base of lamina, lamina lanceolate-ovate, widest in upper third, base attenuate, slightly decurrent, apex acuminate, 11.5–14.5 × 3–4 cm, margin dentate, with (10) 12 pairs of teeth with gland-tipped appendages, acumen at apex 8–12 mm long. Inflorescence axillary, with (2) 5–6 flowers. Peduncle 2–3 mm long. Bracts linear-lanceolate, 6–7 × 1 mm. Pedicels 6.5–8.2 cm long, reddish. Flowers pinkish-purple with red mark on lower petals, spur violet. Lateral sepals ovate, acuminate, 7–8 x 2 mm. Lower sepal navicular, 15 × 8 mm, with curved spur, 20–25 mm long. Dorsal petal cucullate, with short spur at apex, 23–26 × 18–20

mm. Lateral united petals 35 mm long, upper petal deeply emarginated at apex, 20 × 14 mm, lower deeply emarginated at apex, 30 × 15 mm. Anthers 4–5 mm long. Ovary 4–5 mm long. Fruit elongate, 20 × 4–5 mm.

Habitat: —Perhumid montane forest along creek, 1140 m.

Distribution: — Madagascar, Masoala Peninsula, only known from the type collection.

Etymology: —Dedicated to Otto and Eleonore Gunthilde Karolina Schweizer by the family of Andreas Schweitzer on the occasion of the 80 th birthday of Eleonore for the generous support of taxonomic research.

Notes: — Impatiens otto-eleonorae is related to Impatiens hildebrandtii Baillon (1886: 595) , which was considered as a synonym of Impatiens firmula Baker (1883: 114) by Perrier de la Bathie (1934). It differs, however, in several features ( Table 1), e.g., larger habit, the larger leaves, the inflorescences with up to 6 flowers and the larger flowers. Impatiens hildebrandtii occurs in Eastern Central Madagascar in rainforests (e.g.Andasibe and Ranomafana). Impatiens otto-eleonorae is restricted to perhumid montane forests on Masoala Peninsula.

Figures

FIGURE 1. Impatiens otto-eleonorae. A, B, habit, C, leaf, D, flower, E, lateral sepal, F, lower sepal and spur, G, dorsal petal, H, I, lateral united petals. All drawn from the type by E. Fischer.

FIGURE 2. Impatiens otto-eleonorae. A, habit with inflorescence. B, flowers. Impatiens hildebrandtii. C, flower. Impatiens firmula. D, flower.A, B, phot. P.P.Lowry, Masoala, C, D, phot. E. Fischer, Angavokely, Andasibe. Scale bar A: 2 cm, B–D: 1 cm.