Begonia crockerensis Rimi, 2015

Repin, Rimi, Sang, Julia, Kiew, Ruth & Mujih, Handry, 2015, Eleven new species of Begonia (Begoniaceae) from the Crocker Range, Sabah, Malaysia, Phytotaxa 208 (1), pp. 1-20 : 8-9

4. Begonia crockerensis Rimi , spec. nov. ( Figure 5 )

Sect. Petermannia

It is similar to B. humericola Sands (2001: 156) in its creeping habit, leaf margins that are shallowly lobed or have large teeth and in its white male flowers with 4 tepals but it is different in being a much smaller plant with stems to 13.5 cm long (not 40 cm or longer as in B. humericola ), its small stipules 14–23 × 5–7 mm (not 10–20 × 6–11 mm), smaller lamina 4.5–5.5 × 3.5–5 cm that are glabrous (not 5–9 × 2.5–5.3 cm with flexuose hairs 3–4 mm long) and its capsules are broader than long, 4–6 × 6–12 mm (not suborbicular and 6–6.5 mm across).

Type:— MALAYSIA. Borneo. Sabah. Penampang District: Crocker Range, Kipandi Butterfly Park , 26 Aug 2014, Julia & Kiew KNP 36816 (holotype SNP!; isotype SAN!) .

Creeping begonia rooting at the nodes. Stem glossy, dark magenta, ca. 13.5 × 0.4 cm, hispid with scattered white hairs, slightly succulent, swollen at nodes, internodes 2.3–2.6 cm long. Stipules greenish, glabrous, lanceolate, 14–23 × 5–7 mm, margin with sparse hairs, apex acute, persistent. Leaves upstanding or semi-erect, distant, not oblique; petiole deep magenta, hispid, hairs white, 1.7–2.3 cm long, slightly grooved above; lamina deep plain bronzy green above, deep magenta below, plain green above, light green below, thinly fleshy when fresh, slightly glossy, ovate, slightly asymmetric, 4.5–5.5 × 3.5–5 cm, broad side 2.3–2.9 cm wide, base slightly rounded, basal lobes to 2 mm long, margin wavy, slightly toothed at the vein endings, apex acute; venation palmate-pinnate, veins concolorous, 3 on each side of the midrib, fine veins in the basal lobe, glabrous above, shortly hairy underneath, impressed above, prominent beneath. Inflorescences protogynous, axillary from the upper nodes, racemose, glabrous, erect, rachis magenta, 2.7–8 cm long, peduncle 2.7–6.5 cm long, first branch with single female flower, upper branch terminating in 3 male flowers. Bracts glabrous, greenish, lanceolate, 10–12 × 6–7 mm, caducous; lower bracteoles magenta, oval, ca. 7 × 4 mm; upper bracteoles green, in pairs, 4–7 × 4–6 mm, margin entire, persistent. Female flower: pedicel ca. 3 mm long, pale pink, glabrous; ovary greenish, deltoid, ca. 5 × 12 mm long (width across the shorter ones), pure white, wings 3, unequal, pinkish, locules 3, placenta bilamellate with many ovules on both surfaces; tepals 5, pure white, oval, margin entire, apex rounded, outermost four tepals ca. 12 × 4.5 mm, innermost tepal smaller, ca. 9 × 3 mm; styles 3, 1.5–3 mm long, joined at base to form a greenish stalk to 0.8 mm long, branches ca. 2 mm long, deep yellow, Y-shaped with almost flat top; stigma papillose forming a continuous twisted band. Male flowers: pedicel white or magenta, 6–10 mm long; tepals 4, glabrous, white tinged greenish at the base, margin entire, outer 2 tepals oval, ca. 10 × 6 mm, apex rounded; inner 2 tepals narrowly lanceolate, ca. 6 × 3 mm, apex acute; stamens 17, cluster conical, stalked, ca. 0.3 mm long; filament yellow, 0.6–1 mm long; anthers yellow, obovate, ca. 0.6 × 0.4 mm, apex emarginate. Capsule dangling on a fine thread-like pedicel, 12–13 mm long; fruit 4–6 × 6–12 mm, glabrous, locules 3, wings unequal, triangular, narrowed to the base, pointed distally, 2 shorter wings ca. 3 mm wide, larger one 4–5.5 mm wide, thinly fibrous, dehiscing between locules and wing. Seed: oblong, ca. 0.3 × 0.1 mm, columnar cells more than half the length of seed.

Distribution:—Common around Kipandi, Penampang District. From its currently known distribution this species is narrowly endemic to the Crocker Range.

Habitat:—Lowland to lower montane forest at 120–1200 m elevation.

Etymology:—Named for the locality from where it was collected.

Additional specimen examined: — MALAYSIA. Borneo. Sabah. Papar District: Crocker Range – Mendalipau, Geofarry et al. KNP A15327 (SAN, SNP).

Notes:—This species comes in two colour forms, bronze and green. The more attractive one has bronzy green leaves that are deep magenta beneath compared with the rather plain form with mid-green leaves that are paler green beneath.

Figures

FIGURE 5. Begonia crockerensis. A. Habit of purple form; B. Habit of green form; C. Purple form showing the red-purple lower surface of the leaves; D & E. Male inflorescence and flowers; F. Female flower; G. Female flower and old fruit. Photo A from KNP A15327 by Rimi Repin; photos B–G from KNP 36816 by Julia Sang.