Begonia titoevangelistae D. Tandang & R. Rubite, 2016

Tandang, Danilo N., Rubite, Rosario R., Angeles Jr, Raul T. & De Guzman, Margaret C., 2016, Begonia titoevangelistae (sect. Baryandra, Begoniaceae) a new species from Catanduanes Island, the Philippines, Phytotaxa 282 (4), pp. 273-281 : 276-278

Begonia titoevangelistae D. Tandang & R. Rubite , sp. nov. ( Fig. 2 & 3 ).

Type:— PHILIPPINES. Catanduanes Island: Catanduanes Province, Municipality of Gigmoto, Barangay San Pedro , Nahulugan Falls , moist rocks under trees and shrubs near the waterfalls, elevation ca. 93 m, 13º47’16.6”N, 124º22’01.4”E, 28 June, 2015 (fl. and fr.), D.N. Tandang 1994 (holotype PNH , isotype CAHUP )

Begonia titoevangelistae is distinguished by the asymmetric stipules and the variegated leaves. Stipules are green turning light brown with prominent red keel and hairs that are becoming denser and thicker near the base of the petiole. In the adaxial lamina, the veins are dark green to almost black contrasting with green interveins. In the abaxial lamina, the veins are red with minute red hairs contrasting with cream interveins. The wide obliquely ovate leaf is elongated with shallowly undulate and minutely lobed leaf margin and long acuminate apex.

Monoecious perennial rhizomatous herbs. Rhizome light brown, 4 to 15 cm long, sparsely associated with brown hairs (1–1.5 mm) and lenticels, prostrate, 5–8 mm in diameter, internodes 0.5–2 cm. Stipules green turning light brown, asymmetric, ovate, apex acuminate, 12–18 mm long and 9–12 mm wide with red keel (10–12 mm long and 1.5–2 mm wide), the keel with red hairs (3–8 mm long) becoming denser and thicker near the base of the petiole. Leaves alternate; petiole, reddish brown 18–30 cm long and 5–10 mm thick erect, terete, succulent, with minute brown hairs (379–987 μm); blade obliquely ovate, 11–16 cm long and 9–12 cm wide, adaxial lamina glabrous, veins very dark green to almost black, interveins and margin green, abaxial lamina veins red sparsely associated with red hairs (356–950 μm), interveins and margin cream, base cordate, lobes rounded and overlapping (0.5–1 cm), apex acuminate, margin shallowly undulate, larger lobe with irregular shallowly acute lobes (2 mm long and 3 mm wide) for each tip of primary veins while smaller lobe is almost entire, with brown hair becoming denser and longer (384–691 μm) near the veins, primary veins 8–9. Inflorescence axillary, arising directly from the rhizome, dichotomously branched 5 times; peduncle light reddish brown 25–42 cm long and 3–5 mm thick, erect, glabrous. Bracts caducous, light green, boat shape, glabrous, 8–12 mm long 8–12 mm wide. Male flower: pedicel white to pinkish, glabrous, erect to ascending, 6–10.5 mm long and 0.5–1 mm thick; corolla 19–22.5 × 18–20 mm; tepals 2+2 white, glabrous, outer pair orbicular 9–11 × 8–10 mm, inner pair obovate 8–10 × 4–5 mm; androecium actinomorphic, with 25–30 stamens, filaments 1–1.5 mm long, united at the base; anthers yellow, rounded, 1 mm long. Female flower: pedicel white to pinkish, glabrous, ascending at the beginning then later pointing downward, 8–12 mm long and 0.5–1 mm thick; corolla 18–21 × 18–20 mm; tepals 2+2 white, glabrous, outer pair orbicular 8–10.5 × 8–10 mm; inner pair obovate 6–9 × 3–5 mm; ovary pinkish green, 7–10 × 5–7 mm, wings equal three-locular, placentae axile, bifid; styles three, 2–2.5 mm long, stigma yellow. Capsule glabrous, nodding 10–12 × 15–18 mm equally 3-winged; wings 8–12 × 4–5 mm, rounded.

Etymology:— The species epithet is named after Dr. Luisito T. Evangelista the current Officer in-Charge— Curator I of the Botany Division, National Museum of the Philippines. Dr. Evangelista is fondly called “Sir Tito” by his colleagues thus the specific epithet titoevangelistae .

Distribution and Habitat:—There was o nly one population discovered in June 28, 2015 at Nahulugan Falls, Gigmoto, Catanduanes Island. The plants grow on moist rocks under trees and shrubs near the waterfalls.

Phenology:— The species was flowering and fruiting when collected in June 2015 and September 2016.

Conservation Status:— Only one population of about 300 individuals, was observed on a 100 m area near the waterfalls. The habit is declining since the site is being converted into a tourist spot. The area is not currently protected under the country’s National Integrated Protected Areas System (NIPAS) by the Department of Environment and Natural Resources (DENR). This species is unlike the other members of Begonia sect. Baryandra in the Philippines where they are generally abundant in the type locality. According to the IUCN red list categories and criteria ( IUCN 2012), B. titoevangelistae is hereby proposed to be placed under Critically Endangered (CR) category based on the present situation: restricted geographic range of less than one km 2 area with only one single location (CR:B2a) and about 300 mature individuals by estimation.

Figures

FIGURE 2. Begonia titoevangelistae D.Tandang & R. Rubite. A, Habit; B, Leaf adaxial surface; C, Leaf abaxial surface; D, Inflorescence; E, Carpellate flower, adaxial view; F, Carpellate flower, lateral view; G, Staminate flower, adaxial view; H, Fruit; I, Cross section of ovary; J, Stipule; K, Rhizome. (All from D.N. Tandang 1994).

FIGURE 3. Begonia titoevangelistae D. Tandang & R. Rubite.A, Habit; B, Stipule; C, Leaf apex; D, Inflorescence; E, Carpellate flower, adaxial view; F, Carpellate flower, lateral view; G, Style and stigma; H. Staminate flower; I. Androecium; J, Fruit; K, Cross section of young fruit. (All from D.N. Tandang 1994). Illustrated by Rolf Domini R. Campos.