Mussaenda vidalii Elmer, LPB

Ordas, Jorge Anton D., Pinarok, Neil Alejandro A., Romeroso, Roanne B., Alejandro, Grecebio Jonathan D. & Banag-Moran, Cecilia I., 2019, A checklist of Rubiaceae species from Eastern Samar, Visayas, Philippines, Check List 15 (2), pp. 295-312 : 303

Mussaenda vidalii Elmer, LPB 3 (1911) 993.

Materials examined. Table 2.

Small shrub about 1 m high. Leaves ovate, 2–2.5 × 1.2–1.5 cm, membranous, densely hirsute on both sides especially on the venations. Inflorescences terminal, spreading corymbs. Calyx with a single swollen lobe (calycophyll), white, broadly ovate, 6–8 × 3–8 cm, sparsely pubescent. Corolla infundibular, lobes 4–6 mm, tube 2–3 cm, orange to yellow. Fruits ellipsoid, 1–2 cm, with dense warts.

This species is often observed on secondary forests or in open-regrowth forests of Eastern Samar. While the type specimen of M. vidalii is described as a scandent shrub, most collections of this species are represented by erect shrubs or small trees. In their revision, Alejandro et al. (2015), they noted phenotypic variability of the habit of this species, which ranges from scandent shrubs to small, erect shrubs or trees.