Lobelia philippinensis Skottsb.

Lammers, Th. G., 2011, Revision of the Malesian species of Lobelia section Rhynchopetalum (Campanulaceae: Lobelioideae), Blumea 56 (3), pp. 218-224 : 220-221

1. Lobelia philippinensis Skottsb. — Fig. 1

Plants lacking rhizomes. Stems woody or suffruticose, 1.5 –4 m tall, 5–15 mm diam, simple, erect, fistulose, glabrous or short-pubescent. Leaves sessile, cauline; lamina oblanceolate, narrowly elliptic, or narrowly oblong, 6 –35 by 1–4.8 cm, chartaceous, short-pubescent or glabrous; apex acuminate or sometimes acute; base attenuate; margin callose-serrulate or callose-denticulate. Inflorescence not clearly demarcated, 20 –100-flowered, simple or usually branched toward base; rachis short-pubescent; bracts linear to narrowly elliptic, 9 – 26 by 0.5 – 2 cm, 1.2 – 3 times longer than their pedicels, glabrous or pubescent, acuminate at apex, the margin entire; pedicels spreading or ascending, 6 –18 mm long, bibracteolate at or above middle, densely pubescent; bracteoles linear or subulate, 0.5 –2 mm long. Hypanthium campanulate, oblong, ellipsoid, or broadly ellipsoid, 4 –7 by 3 – 5 mm, glabrous or short-pubescent; base truncate, rounded, obtuse or sometimes acute. Calyx lobes linear, subulate, or linear-triangular, 7–14 by 0.7–1.7 mm, 1.5 – 3.2 times longer than hypanthium, erect or ascending, glabrous or very sparsely short-pubescent; apex acuminate; margin entire and often ciliate. Corolla lavender, pale pink, or white, unilabiate, 26–39 mm long, 4 –8 times longer than hypanthium, glabrous or sparsely short-pubescent on tube externally; tube straight or decurved, 10 –15 by 1.7–4 mm, 4 –7.5 times longer than broad, tapering from base to mouth; dorsal lobes linear or linear-triangular, 10– 25 by 0.5 –1.5 mm; ventral lobes narrowly triangular, 8 – 20 by 1–3 mm, connate for half or more of their length, forming a lip 2.5 –7.5 mm wide. Staminal column exserted, emerging from corolla via its dorsal slit; filament tube 13–18 mm, 2.5–3 times longer than the dorsal anthers, short-pubescent toward base or in lines; anther tube grey, 1.4 –2 mm diam, its surface glabrous or pubescent; dorsal anthers 4 –6 mm long; ventral anthers 3 – 4 mm long, bearded at apex with white trichomes 1.5– 2.5 mm long. Capsule broadly ellipsoid, ellipsoid, or oblong, 5–14 by 4 –8 mm, the beak 2 –4 mm; seeds amber-coloured, 0.4 – 0.6 by 0.3 –0.4 mm, broadly ellipsoid, compressed, often with a single marginal rib, the testa finely striate.

Distribution — Endemic to the Philippines, with three allopatric subspecies endemic to Luzon, Negros, and Biliran.

Figures

Fig. 1 Flowers of Lobelia philippinensis Skottsb. a. subsp. philippinensis; b. subsp.negrosensis Lammers; c. subsp.biliranensis Lammers (a: Elmer 6066, NY; b: Philippine Plant Inventory 6380, BRIT; c: Sulit 5578, L).