Phedimus yangshanicus Z. Chao, 2020

Chao, Zhi, 2020, Phedimus yangshanicus (Crassulaceae), a new species from limestone hills in Guangdong, China, Phytotaxa 429 (2), pp. 148-156 : 153-154

Phedimus yangshanicus Z. Chao , sp. nov. ( Fig. 1 & 2 )

Diagnosis:—This new species is easily distinguishable in the genus by its dimorphic leaves, i.e., pseudopetiolated big basal leaves nearly opposite due to the shortening of the nodes and persistent at anthesis, with alternate small leaves on the erect flowering stem. It is closely related to Ph. odontophyllus , but the latter differs in the creeping young, sterile shoots, and the ascending flowering stems with mostly opposite, dentate leaves of uniform size born in the upper part of the stems.

Type:— CHINA. Guangdong Province: Yangshan county, Changfudong, growing on limestone rocks, 24°30′7″ N, 112°53′14″ E, elevation 380 m, 6 April 2019 (fl. & fr.), Chao Zhi 2019040601 (holotype, Southern Medical University herbarium, SMU!).

Description:—Perennial herbs. Rootstock short, sometimes long and distinct, with 1–2 branches at the top and several slender roots below. Leaves alternate. Basal ones persistent at anthesis, nearly opposite due to shortening of the nodes; leaf blades oval, elliptic, long elliptic or obovate, 3.5–7 cm long, 2.5–3.5 cm wide, soft leathery, often purplish-red, midrib distinct, slightly prominent at the back of the leaf, apex obtuse or acute, margin nearly entire or slightly undulate, base narrowing into obvious pseudopetiole, 3–5 cm long. Main stem stretching out at flowering stage, simple, erect, about 20 cm high, often purple-red, internodes significantly elongated. Leaves on flowering stem much smaller than those at the base, obviously alternate, leaf blades suborbicular, about 1.2 cm in diameter, margin shallowly dentate, pseudopetioles gradually shorter, 0.5–1.2 cm in length. Cymes terminal, sometimes with axillary ones, subtended by a bracteal leaf, mostly 3-branched, obliquely spreading or spreading, branches scorpioid. Flowers sessile, bracteoles leafy. Sepals 5, triangular linear, 5–7 mm long, apex obtuse, base enlarged. Petals 5, golden yellow, lanceolate-oblong, 7–10 mm long, 2–3 mm wide, apex long mucronate, base slightly narrow. Stamens 10, shorter than petals. Nectar scales 5, rectangular, ca. 1.0– 1.5 mm wide, 0.8–1.0 mm high, apex slightly emarginated. Carpels 5, suberect, ovoidoblong, 4–5 mm long, base connate for 0.5–0.7 mm. Follicles stellately horizontal, usually purplish-red when ripening, ca. 7 mm long, base connate for ca. 1 mm, adaxially gibbous. Seeds numerous, striate.

Habitat and distribution:—The new species was found only in its type locality. It inhabits limestone hills and rocks, at an elevation between ca. 200 and 500 m. Fl. and fr. Mar–Apr.

Etymology:—The epithet refers to its type locality, Yangshan County.

Chinese name:—Yangshan Feicai

Figures

FIGURE 1. Habitat, Population and Plant of Phedimus yangshanicus sp. nov. A. habitat; B. Population; C. two blooming individuals; D. young plants; E. whole plant close-up; F. basal leaves, rootstock and roots; G. part of inflorescence.

FIGURE 2. Flower and Fruit Dissection of Phedimus yangshanicus sp. nov. A. flower top-view B. sepals; C. petals and antepetalous stamens; D. carpels and nectar scales at base; E. aggregate follicles; F. ovules, with striate ornamentation.