Malesherbia fatimae M. Weigend & H. Beltrán, 2015

Weigend, Maximilian, Jossberger, Thomas & Beltrán, Hamilton, 2015, Notes on Malesherbia (Passifloraceae) in Peru: a new species from southern Peru, a new record and a first report on interspecific hybridization in Malesherbia, Phytotaxa 202 (4), pp. 250-258 : 252

2. Malesherbia fatimae M. Weigend & H. Beltrán , spec. nov. ( Figs. 1 , 2 , 3 a–c ).

Type: — PERU. Dept. Arequipa: Prov. Condesuyos. Distr. Chuquibamba. Road from Aplao (Castilla) to Chuquibamba, S of bridge over Río Arma, Quebrada Huario, ca. 24.5–26 km from Chuquibamba, dry scree slope with scattered Neoraimondia and Larrea divaricata , only on near. vertical rock faces, 1550 m, 15°55´S, 072°33´W, 24 July 2010, M. Weigend, F. Cáceres-H. & U. Baldárrago 9372 ( USM, isotypes: B, F, HUSA, BONN, M).

Erect shrub to ca. 1 m, stems cylindrical, basally up to 20 mm wide, branches erect, up to 80 cm long, sparsely branched, densely tomentose. Leaves alternate, lamina elliptical to obovate, 10–55 × 5–15 mm, apex rounded, base rounded to cuneate, margin irregularly crenate, dentate to lobulate with 5–7 lobules/major serrations on each side, planar to slightly incurved, adaxially and abaxially densely white and tomentose, abaxially with primary and secondary veins elevated, with 5–9 pairs of secondary veins. Inflorescences simple, loose racemes 5–6 cm long. Flowers axillary, pedicels 3–4 mm long, densely pubescent to tomentose. Bracts linear to elliptical, 3–5 × 1–2 mm, densely pubescent. Perianth tube cylindrical, gradually dilated towards the middle and narrowed towards the apex, 30–35 mm long and 3–4 mm wide near base, 7–9 mm wide in median portion, abaxially pubescent, adaxially glabrous, basally green with 10 green veins extending onto the red median portion of tube. Calyx lobes 5, triangular-ovate with rounded apex, 3–4 × 1.5–3 mm, densely pubescent on both sides. Petals 5, triangular-ovate with rounded apex, 3–4 × 2–4 mm, apex acute, scarlet red, pubescent especially abaxially, venation pinnate. Corona membranaceous, of five bidentate processes, 1–1.5 × 2 mm, pale red. Androgynophore ca. 3 mm long, glabrous or sparsely pubescent, and with apical disc-shaped dilation, 2–3 mm wide, pubescent. Stamens 5, 35–40 mm long, anthers long exserted, filaments glabrous, distally tinged with red; anthers oblong, 2 × 0.9–1.1 mm, papillose. Ovary ovoid, 3–4 × 1 mm, apically pilose, otherwise glabrous. Styles 3, 45–50 mm long, glabrous, apically tinged with red. Stigmas slightly dilated, papillose. Fruit a capsule, 25–30 mm long, glabrous, opening with 3 acuminate and pubescent apical valves each 6–12 mm long, seeds numerous, elliptical, black, ca. 2 × 1 mm, numerous.

Additional specimens examined (paratypes):— PERU. Dept. Arequipa: Prov. Condesuyos, Distr. Chuquibamba. Rock slope, 3 September 1977, Weibel 05 ( USM) ; Aplao to Chuquibamba , 1–24 June 2011, N. Dostert 1032 ( HUSA, BONN) .

Notes: — Malesherbia fatimae is unique among Peruvian Malesherbia with its stiffly erect, loosely branched habit and densely tomentose, but eglandular indument. The other perennial species are usually compact, densely foliose shrubs with characteristic long glands, especially on the leaves. Malesherbia fatimae has planar, elliptical to obovate, distinctly petiolate leaves without clear stipules, whereas the other perennial species usually have narrowly ovate to lanceolate leaves, with a distinctly undulate margin, usually with an indistinct petiole. This new species is thus morphologically quite isolated in the group.

Distribution: —The new species is so far only known from the type locality in Chuquibamba, on the steep, desertic rock slopes where a a few individuals were located in a quebrada branching off into the mountain slope.

Habitat and ecology: —The new species was only found on steep rock slopes rooting in loose rock and crevices.

Phenology: — Malesherbia fatimae apparently flowers throughout the year, like many desert shrubs from this habitat, probably with a peak after the rainfalls in March–April.

Ethymology: —The species is named in honour of our friend Fatima Cáceres Huamaní, a botanist from the Universidad Nacional de San Augustín, Arequipa, Peru. She participated in the field study leading to the discovery of this species.

Conservation status: —According to the Red List criteria of the Lista Roja de UICN (UICN, 2001), the species should be included into the category “not evaluated” (NE), since it is only known from a single locality.

Figures

FIGURE 1. Malesherbia fatimae, line drawing. a. habit and inflorescence; b. leaf; c. calyx lobe; d. petal; e. corona; f. calyx and corolla seen from adaxial side, corona removed; g. androgynophore, stamens, ovary, and styles [drawn from Weibel 05 (USM) by Hamilton Beltrán].

FIGURE 2. Malesherbia fatimae, photographic plate. a. inflorescence; b. flower; c. leaf, abaxial and adaxial side; d. androgynophore (with bracts and bractoles attached); e. Perianth, seen from adaxial side; f. corona and perianth seen from adaxial side (M. Weigend et al. 9372).

FIGURE 3. Malesherbia fatimae and M. tenuifolia in native habitat. a. M. fatimae, inflorescence (M. Weigend et al. 9370). b. M. fatimae growing on rock face. c. Habitat of M. fatimae. d. M. tenuifolia (M. Weigend et al. 9368). e. M. tenuifolia (M. Weigend et al. 9369). f. habitat of M. tenuifolia.