Malesherbia fatimae H. Beltrán & M. Weigend

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 : 256

3. Malesherbia fatimae H. Beltrán & M. Weigend (infra) × tenuifolia D. Don (1832: 244) ( Figs. 4 a–c ).

Shrub to ca. 1 m, branched from base with branches up to 80 cm long. Leaves alternate, 10–30 × 5–10 mm, apex acute, base cuneate, margin irregularly pinnatifid with 3–5 lobules on each side, these coarsely dentate with 1–3 teeth, planar, adaxially and abaxially densely pubescent. Inflorescences simple, dense racemes 5–8 cm long. Flowers axillary, pedicels 5–10 mm long, pubescent. Bracts narrowly elliptical, 5–10 × 1–3 mm, pubescent. Perianth tube cylindrical, slightly narrowed towards the base, 30 mm long and 3–4 mm wide near base, 7–9 mm wide in median portion. Calyx lobes 5, triangular-ovate with rounded apex, 5–7 × 2–3 mm, densely pubescent on both sides. Petals 5, triangular-ovate with rounded apex, 5–7 × 3–5 mm, apex acute, carmine, pubescent especially abaxially, venation pinnate. Fruit a capsule, 30–35 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.

Specimens seen: — PERU. Dept. Arequipa: Prov. Condesuyos: Road from Aplao (Castilla) to Chuquibamba, S of bridge over Río Arma, Quebrada Huario, ca. 24.5–26 km from Chuquibamba, dry scree slopes, 1550 m, S 15° 55´, W 072° 33´, 24 July 2010, M. Weigend, F. Cáceres-H. & U. Baldárrago 9370 (USM, B, F, HUSA, BONN, M).

Notes: —The plants were found in a large population of M. tenuifolia along the road cut, approximately 50 m from the only known population of M. fatimae . The specimens show a clearly intermediate expression of characters, with leaves pinnate as in M. tenuifolia , but not with linear leaf lobes, but rather narrowly lanceolate ones. Whereas M. tenuifolia is glabrescent and M. fatimae is white-tomentose, the putative hybrid is densely pubescent. Flower color is not scarlet as in M. fatimae and not white to pink as in M. tenuifolia , but rather carmine.

The hybrid, while highly characteristic, is not here described as new nothospecies, since it is unclear whether it represents a stabilized hybrid and is able to generatively propagate true to type. Experimental studies and additional field observations would clearly be required to verify the status of this plant. Specimens of the putative parental species can be found above.

Figures

FIGURE 4. Malesherbia hybrids. a. Malesherbia fatimae × tenuifolia, inflorescence (M. Weigend et al. 9370); b. Malesherbia fatimae × tenuifolia, leaves (M. Weigend et al. 9370); c. Profesora Fatima Cáceres Huamaní with a bunch of Malesherbia fatimae × tenuifolia and Malesherbia tenuifolia; d. Inflorescence of Malesherbia arequipensis (left), M. ardens (right), Malesherbia ardens × arequipensis (middle; same collections as in e, f, and g); e. Leaves of M. ardens (M. Weigend et al. 7866); f. Leaves of M. ardens × arequipensis (M. Weigend et al. 7868). g. Leaves of M. arequipensis (M. Weigend et al. 7865).