Drosera undetermined

Coritico, F. P. & Fleischmann, A., 2016, The first record of the boreal bog species Drosera rotundifolia (Droseraceae) from the Philippines, and a key to the Philippine sundews, Blumea 61 (1), pp. 24-28 : 27-28

KEY TO THE DROSERA SPECIES OF THE PHILIPPINES

Note — Islands and provinces of known occurrences are mentioned after the m-dash, synonyms as appearing in the Philippine floras are given in parentheses behind the species names; distribution data based on (and updated from) Planchon 1848, Merrill 1922, Van Steenis 1953, Fleischmann et al. 2011, Pelser & Suarez 2014, Galang 2014. For a distribution map of the Philippine species, see Fig. 3.

1. Plants caulescent, with distinctive, elongated internodes 2

1. Plants rosetted, sometimes forming columns of dead leaves with age...................................... 4

2. Lamina filiform, linear; stem and scapes finely glandular pubescent; annual plant from lowland areas............ 3

2. Laminapeltate,auriculate;stemandscapesglabrous;tuberous perennial from highland areas. — Luzon : Bontoc, Benguet, Zambales; Mindoro : Mt Halcon.............. D. lunata ............. (syn. D. peltata var. lunata , D. peltata s.l.)

3. Plants 5–10 cm tall, leaves 2–5 cm long, scapes 3–5(–8)- flowered; leaves with short petiole (a space of 1–10 mm on the leaf between stem and carnivorous glands), petioles with microscopic glandular trichomes; stem with microscopic translucent glandular hairs; stipules reduced to 2 filiform setae or absent. — Luzon : Central Luzon , Rizal; Western Visayas: Malalison island; Palawan: Culion island....................... D. indica (syn. D. hexagynia Blanco )

3. Plants (9–) 15–30 cm tall, leaves (6–) 10–15 cm long, scapes (6–)10–20-flowered; leaves with distinct petiole (a space of 10–12 mm on the leaf between stem and carnivorous glands), petioles with scattered, microscopic Y-shaped trichomes and non-glandular hairs; stem with microscopic translucent non-glandular hairs and scattered larger, red glands; stipules always absent. — Luzon : Pangasinan ....... D. serpens

4. Styles 5; scapes entirely glabrous, calyx densely glandular; leaves broadly cuneate, with very short inconspicuous petioles. — Luzon : Bontoc; Western Visayas: Malalison and Panay islands......................... D. burmannii

4. Styles 3; scapes glandular or glabrous; leaves spathulate to narrowly cuneate or oblong to oblanceolate, petiolate 5

5. Scapes and calyx glabrous; lamina orbicular, wider than long (4–7 by 5–8 mm); ripe seeds fusiform, brown. — Mindanao : Budnikon (Mt Limbawon)............... D. rotundifolia

5. Scapes and calyx (sparsely) glandular; lamina spathulate to oblong, much longer than wide (not wider than 5 mm); ripe seeds ellipsoid, black............................ 6

6. Leaves erect to semi-erect; lamina narrowly oblong to oblanceolate; plants frequently forming columns; stipules of living plants reddish. — Palawan: Palawan ( Mt Mantalingahan , Mt Victoria)............................ D. ultramafica

6. Leaves flat on the ground; lamina spathulate to narrowly cuneate; plants occasionally forming columns; stipules of living plants papery white. — Luzon : Albay (Mt Mayon), Isabela (Northern Sierra Madre), Aurora (Mt Mahojeg); Mindoro : Oriental Mindoro (Mt Halcon)............ D. spatulata