Medinilla theresae Fernando

Terrestrial, erect shrub up to 1.5 m tall. Stem 1−2 cm diameter near the base of the plant, terete, internodes to 12 cm long, shorter on the distal branches; nodes rather thickened, knobby, not setose, although small barbules may sometimes appear on younger nodes; bark generally smooth, becoming striate on older stems; young stems terete, about 3 mm in diameter, green. Leaves simple, petiolate, in whorls of 3 or 4 per node; petiole ascending, about 3−5 mm thick, 0.5−2 cm long, pale light green, sometimes with dark purplish-red or maroon tinge on the adaxial side; lamina lanceolate, 5−12 × 1.5−4 cm, glossy dark green adaxially, paler abaxially, succulent when fresh, coriaceous when dry; base obtuse, apex acuminate; 3-plinerved, the pair of secondary veins diverging about 2−5 mm from the leaf base, in fresh specimens only visible on the adaxial surface, very faintly so and only near the leaf base on the abaxial surface, in dry specimens visible only on the adaxial surface; transverse veins faintly visible on adaxial surface in fresh and dry specimens, indistinct or absent abaxially; margins smooth, revolute at the edges. Inflorescences cauline, not terminal, arising from leafless nodes, sometimes near the base of the stem, or from leafy nodes, pendulous, usually solitary, or sometimes two or three per node; peduncle about 2.5−6 cm long, enlarged towards the distal end, bright red at maturity, bracteate, each bract 4 × 3 mm; flowers up to 15 or more per inflorescence, usually clustered in a whorl of short, 3-flowered cymes only at the enlarged, distal end of the peduncle, sometimes in 2−3 whorls; 10 or so arranged in umbellately cymose clustered branches up to about 1 cm long, also subtended by bracts; secondary bracts spatulate, 3 × 2 mm; total inflorescence length about 7 cm. Flower buds ± rounded at the tips, the petals imbricate. Flowers 4-merous, petal 8 × 4 mm, oblique-oblong, often reflexed, orange-red, red, or pink; stamens 8, usually positioned above the style, anthers linear-lanceolate, 2.5−4 mm long, rather straight, purple, with a yellow dorsal spur of 0.6 mm long on the connective and a pair of partly joined stout, ventral appendages at the base of the anther sac; filament 4 mm long, pale white; style terete, 10 mm long, pale white; hypanthium campanulate, the rim generally truncate or sometimes very shallowly lobed, pale or light green, 3−4 × 3−4 mm; pedicel pale pink or red, about 7 mm long. Fruit a subglobose berry, 4−6 × 5−7 mm, light green when young and with bright red calyx rim, entirely purplish-black when ripe; the peduncle and pedicels red. Seeds numerous, embedded in pulpy tissue, ovoid, 1−1.5 × 0.5−1 mm, chestnut brown. Seedling with epigeal germination, phanerocotylar, cotyledons foliaceus, 2−3 × 2 mm, broadly ovate, apex rounded or obtuse, sometimes shallowly emarginate; eophylls simple, opposite, broadly elliptic-ovate to orbicular, 3−7 × 3−5 mm.

Thus far, this new species is known only from Mt Redondo on Dinagat Island and Mt Hamiguitan in the Pujada Peninsula on Mindanao Island, Philippines. Dinagat Island, Surigao del Norte Province, and the Pujada Peninsula form part of the same belt of the Eastern Philippine Cretaceous ophiolite and ophiolite complexes (Balce et al. 1976; Yumul et al. 2003, 2008; Tamayo et al. 2004) that are now large areas of ultramafic landscapes with metallic ore deposits (e.g., iron, nickel, chromium) and hosting a unique type of forest formation (Fernando et al. 2008).