Malesherbia laraosensis H. Beltrán & M. Weigend, 2014

Beltran, Hamilton & Weigend, Maximilian, 2014, A new species of Malesherbia (Passifloraceae Subfam. Malesherbioideae) from Peru, Phytotaxa 172 (3), pp. 285-288 : 286

Malesherbia laraosensis H. Beltrán & M. Weigend spec. nov. ( Fig. 1 )

Type: — PERU: Dept. Lima: Prov. Yauyos. District of Laraos. Quichao , 4 km from village, 12º 20´37´´S, 075º 49´09´´ W, 3510 m, 18 May 2010, Hamilton Beltrán 6885 (holotype: USM; isotypes: B, F, HUT, MO, UNAS, UPAO) .

Caespitose shrublet, primary shoot short, basally ca. 13 mm wide, branches prostrate to decumbent, up to 15 cm long and basally 2–3 mm thick. Leaves alternate, lamina obovate to narrowly obovate, 10–30 mm long, 3–7 mm wide, apex rounded, base cuneate, margin subentire to irregularly serrate with 7—8 teeth on each side, strongly undulate, especially distally, adaxially dark green and subglabrous, abaxially densely sericeous, abaxially with primary and secondary veins elevated, with three pairs of secondary veins. Inflorescences simple, dense racemes 4–5 cm long. Flowers axillary, pedicels 9–12 mm long, sericeous. Bracts linear, 5–6 mm long and 2–3 mm wide, sericeous. Perianth tube cylindrical, gradually dilated towards the middle and narrowed towards the apex, 25–27 mm long and 4–5 mm wide near base, 8–11 mm wide in the middle and 6–7 mm wide at the apex, abaxially sericeous, trichomes up to 1 mm long, adaxially glabrous, green at base and yellowish red near the apex, with 10 greenish veins distally branched in three. Sepals 5, triangular-ovate, 5 mm long and 2–3 mm wide, pubescent on both sides, apically reddish, threeveined. Petals 5, ovate-elliptical, 3.5–4 mm long and 0.9 mm wide at base, 1.2 mm wide in the middle, apex acute, red, pubescent on both sides, venation pinnate. Corona membranaceous, 1.9 mm long, formed by five bidentate processes. Androgynophore 2 mm long, glabrous, and with apical disc-shaped dilation, 2–3 mm wide, hirsute. Stamens 5, 24– 26 mm long, anthers exserted, filaments glabrous, distally tinged with red; anthers oblong, 2 mm long and 0.9-1.1 mm wide. Ovary globose, 2 mm long and wide, apically pilose, otherwise glabrous. Styles 3, 20 mm long, 4 mm wide, glabrous, apically tinged with red. Stigmas slightly bilobed and dilated, papillose. Fruit a capsule, 16 mm long, glabrous, opening with 3 acuminate and pubescent apical valves, seeds beige, numerous.

Additional specimen examined (paratype): — PERU: Dept. Lima: Prov.Yauyos. District of Alis. Carlos Romero Carbajal s.n. ( USM) .

Notes: — Malesherbia laraosensis is unique among Peruvian Malesherbia with its caespitose habit with very short branches (up to 15 cm long) and differs dramatically from all previously known Peruvian species with similar floral morphology, which are much larger (usually> 50 cm tall) and branched mainly above. Malesherbia arequipensis is the only other species that is similiarly small, but it is an annual or short-lived perennial with deeply and repeteadly pinnatisect leaves and white flowers. In floral colour and morphology M. laraosensis most closely resembles M. splendens Ricardi (1965: 6) and M. scarlatiflora Gilg (1913: 11) , but both species are ca. 1 m tall, have long, ovateacuminate, densely villous leaves, and have longer sepals than petals. Conversely, the leaves of M. laraosensis are obovate, abaxially sericeous and adaxially subglabrous, with only few teeth on both sides, and the sepals and petals are more or less the same size.

Malesherbia scarlatiflora is the only other species known from the area of the type collection of M. laraoesensis . Based on phytogeography and morphology the new species appears to belong to Malesherbia sect. Malesherbia , a group centred in Central Peru.

Distribution: —The new species is so far only known from the type locality in Laraos, an area with little human intervention.

Habitat and ecology: —Soils are calcareous and vegetation is dominated by shrubs of Baccharis spp. , Columellia obovata Ruiz & Pavón (1798:28) , Jungia schuerae Harling (1992:16) , Fabiana fiebrigii Arroyo (1976:50) and Senecio larahuinensis H. Beltrán & A. Galan (1998:168) , and herbaceous species, such as Salvia oppositiflora Ruiz & Pavón (1798:26) .

Phenology: — Malesherbia laraosensis flowers from May to July.

Ethymology: — The species name refers to the type locality in the Laraos District .

Conservation status: —According to the Red List criteria of IUCN (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 laraosensis. a. Flowering branch; b. Flower; c. stamens and styles; d. Adaxial view of inside of perianth showing details of the corona.a-d from Beltrán 6885.