Begonia conniegeriae S.Julia & Kiew, 2013

Sang, Julia, Kiew, Ruth & Geri, Connie, 2013, Revision of Begonia (Begoniaceae) from the Melinau Limestone in Gunung Mulu National Park and Gunung Buda National Park, Sarawak, Borneo, including thirteen new species, Phytotaxa 99 (1), pp. 1-34 : 10-12

4. Begonia conniegeriae S.Julia & Kiew , spec. nov. ( Figure 6 )

Sect. Petermannia

Begonia conniegeriae is similar to B. congesta Ridley (1906: 253) from the Bau limestone in Kuching Division, in its leaves that are neither hairy nor appear velvety and in its distantly toothed leaf margin, but it is distinct from B. congesta in its glossy leaves, its larger elliptic male tepals ca. 7 × 3 mm (not rotund and 4–5 × 4–5 mm) on longer pedicals 8–10 mm (not 5–7 mm long) and in its shorter fruits 20–22 mm (not ca. 25 mm long) and oblong fruits (not almost square in outline).

Type: — MALAYSIA. Borneo. Sarawak. Marudi District: Gunung Mulu National Park, Lobang Cina , 15 April 2012, Julia et al. SFC 2807 (holotype SAR!; isotypes E!, K!, KEP!, L!, SING!) .

Erect begonia. Indumentum on stem and petiole reddish brown with sparse with unbranched short hairs and sparse stiff hairs on upper surface of leaves, sparsely hairy on veins beneath. Stem fleshy in life and 5 mm diameter, ridged and 2–3 mm when dried, reddish or red brown, swollen on the nodes, internodes 2–7.5 cm long. Stipules greenish or greenish brown, with a distinct midrib, lanceolate, ca. 12 × 3 mm, margin entire, apex pointed, caducous. Leaves alternate, distant, held horizontally. Petioles (3.5–)5–13(–18) cm, terete. Laminas dark green above, paler beneath, bluish and with white spots when young, glabrous below, stiffly thinly papery when dried, oblique, broadly ovate, 9.5–21.5 × 8.5–17.5 cm, asymmetric, broad side 7.5–12 cm, base cordate, basal lobes 1.5–5 cm, margin shallowly dentate, apex acuminate, acumen to 1 cm long; venation palmate, main veins beneath red until the first dichotomy, 3 pairs at base, on upper surface red at base with a further 3 veins along the midrib, branching 3 times before reaching the margin, impressed above, beneath very prominent. Inflorescences axillary, erect and shorter than petioles, racemose, protogynous, 3–4 cm long, peduncle 2–2.5 cm long, with 1– 2 female flowers, and above a spike 1–1.2 cm long of male flowers. Bract pair elliptic, sparsely hairy, brownish green, ca. 14 × 7 mm, margin entire, persistent; uppermost bracts pale green, with distinct midrib, elliptic, glabrous, ca. 10 × 6 mm. Male flower: pedicel white, 8–10 mm; tepals 2, pinkish, glabrous, broadly elliptic, ca. 7 × 3 mm, margin entire, apex almost rounded; stamens 30–42, cluster conical, stalk ca. 0.5 mm long; filaments 1–1.2 mm long; anthers pale yellow, obovate, 0.8–1 × 0.3–0.5 mm, apex emarginate. Female flower: pedicel pale green, ca. 8 mm, sparsely hairy; ovary reddish, elliptic, 18–20 × 6 mm, wings 3, pale green, unequal, locules 3, placental branches 2 per locule; tepals 5, pale pink, outer one smaller, narrowly elliptic, 8–10 × 5 mm, inner one bigger, elliptic, 10–12 × 6–7 mm, margin entire, apex acute; styles 3, yellow, ca. 7 mm long, free to base, bifurcating with the ultimate branches broadly U-shaped and curled at the tips; stigma pale yellow, forming a continuous twisted papillose band. Fruits pendent; pedicel ca. 5 mm long, glabrous, stiff and recurved; capsule reddish, elliptic or oblong slightly wider at the tip, 20–22 mm long, 12–15 mm wide, glabrous, locules 3, wings unequal, cuneate proximally, slightly truncate distally, 4–6 mm wide, papery, dehiscing between the wings and locules. Seeds barrel-shaped, ca. 0.3 mm long, collar cells equal or more than half the seed length.

Distribution: — MALAYSIA. Borneo. Sarawak. Marudi District: Gunung Mulu National Park, Melinau limestone, Lobang Cina.

Habitat: —In lowland limestone forest, near streams or foothills on limestone-derived soil in light shade at 102–202 m elevation.

Etymology: —Named after Ms Connie Geri, Biologist at Sarawak Forestry Corporation (2007-present) who organized the field trips to Gunung Mulu National Park and is an active collector of limestone plants including begonias.

Additional specimens examined (paratypes): — MALAYSIA. Borneo. Sarawak. Marudi District: Gunung Mulu National Park – Lobang Cina, Julia et al. SFC 3013 ( KEP, SAN, SAR); Path to Deer Cave from base camp, Kiew RK 546 ( KEP) .

Notes: —This species belongs to a group of begonias that has apparently diversified on limestone hills. The first to be described was B. congesta Ridley from the Bau limestone, Kuching Division ( Ridley 1906). In Mulu three species occur, B. conniegeriae , B. melinauensis and B. umbratica . They are erect shrubby begonias characterized by their thick stems often swollen nodes, the narrowly bifurcating veins that give the leaf surface a corrugate appearance, the often congested basal branches of the inflorescence and the many tiny flowers. In the field each species is distinctive but some characters, for examples, velvety appearance of the lamina ( B. melinauensis and B. umbratica ) or the orientation of the leaf ( B. melinauensis ) are lost on pressing and drying. This species is a case in point because its glossy leaves so conspicuous in the field separate it from the other species in this group.

Figures

FIGURE 6. Begonia conniegeriae. A. habit; B. leaves of juvenile plant with white spots; C. two inflorescences – on left in the female phase with single mature female flower and many young buds of male flowers; on right in the male phase with maturing fruits and many opening male flowers. Photos A & B from SFC 2807 by Julia Sang; photo C from SFC 3013 by Connie Geri.