Toona calcicola
Distribution.— Endemic (so far known only from the type locality).
DESCRIPTION
Toona calcicola Rueangr., Tagane & Suddee, sp.nov.
Erect inflorescences and subsessile to short petiolules up to 2 mm long are characteristic of this species, differing from all the other species of Toona. Phenotypically similar to Toona ciliata M. Roem. but differs in having puberulent leaf blades on both surfaces, cordate leaf base (vs. rounded and mostly oblique), short petiolules (vs. 0.2–10(–14) mm
long), calyx lobes valvate (vs. imbricate), glabrous disc and ovary (vs. puberulent) and 8–10 ovules (vs. 5–8 ovules). It is also similar to T. sinensis (A. Juss.) M. Roem., but iffering in its ciliate margins of petals (vs. not ciliate), more ovules (vs. 6 ovules) and absence of staminodes (vs. always presence). Type. Thailand. Loei, Suan Hin Pha Ngam Park, Suan Sawan Nature Trail, limestone area, 17°03’31.50”N, 101°45’45.45”E, alt. 547 m, 8 Dec. 2014, Tagane et al. T3673 (fl . & young fr.) (holotype BKF!; isotypes FU!, K, KYO!, P).
Trees, 8 m tall; bark grayish white to brown, fi ssured and fl aking; young twigs 1–1.3 cm in diam, puberulent, lenticellate. Leaf scar obcordate, 0.8–1.4 × 0.7–1.1 cm. Leaves spiral, paripinnate, occasionally abort one leafl et on top (looks imparipinnate), 32–55 cm long; petiole 6.5–13.5 cm long, puberulent, lenticellate, rachis puberulent, lenticellate; leafl ets opposite, (6–)8–14 pairs; petiolules subsessile to 2 mm long, puberulent; leafl ets blades ovate-lanceolate to oblong-lanceolate, 3–12 × 1.4–4.7 cm, apex acuminate, margin entire, revolute, base cordate, asymmetric, glabrous except minutely puberulent on veins on adaxial surface, densely puberulent and glaucous on abaxial surface, midrib densely hairy, sunken adaxially, prominent abaxially with small lenticels, lateral veins 20–28 pairs, looped to upper ones near margin, densely hairy, sunken adaxially, prominent abaxially, tertiary veins scalariform- reticulate, inconspicuous on upper surface, prominent on lower surface. Infl orescences terminal, erect, panicle, 59–79.5 cm long, rachis puberulent, reddish brown. Flowers ca 5 mm in diam. Pedicle 0.5–1.6 mm long, densely puberulent. Calyx 5(–6), ca 1.5 mm long, outside hairy, inside glabrous, 5-lobed, free; sepals broadly triangular, ca 1–1.2 × 1.3–1.6 mm, margins shortly ciliate. Petals 5(–6), cream in vivo, elliptic-oblong 5 × 2.5–3 mm, raised on the mid-part near base inside and inserted on the androgynophore (disk), apex acute to obtuse, both surfaces puberulent, denser near margin on the outside, margins ciliate, denser at the middle on the inside. Male fl owers: anthers 5(–6), 1.2 × 0.6–0.8 mm, fi laments ca 1.8 mm long, glabrous; disk 1.8–2 mm in diam., yellowish to reddish orange; ovary 5- ocular, ca 2.5 × 2.0 mm, glabrous; style ca 2.5 mm long, glabrous, stigma capitate, ca 1 mm in diam. Female fl owers: antherodes (non-functional anthers) 5(–6), ca 0.8 × 0.4 mm, fi laments 1.1–1.3 mm long, glabrous; staminodes absent; disk 1.8–2 mm in diam., reddish orange, glabrous; ovary 5-locular, 3 × 2.3 mm, glabrous, lenticellate; ovules 8–10 per locule; style ca 1.1 mm long, glabrous, stigma capitate, ca 1.2 mm in diam. Mature capsule, ovoid, 2–2.5 × 2.5–3 cm, with scattered lenticels, opening from apex with 5 valves; columella softly woody, 5-angled to shallowly 5-winged, extending to apex of capsule. Seed, winged at one end, fl at, 1.2–2 × 0.4–0.8 cm, body 0.5–1 × 0.2–0.5 cm, brown when dry, attached by seed-end to proximal part of the columella.
Distribution.— Endemic (so far known only from the type locality).
Vernacular.— Yom hin pun (ยมหินปูน).
Ecology.— In ridge of limestone hill; alt. ca 550 m.
Phenology.— Flowering: November–December.
Fruiting: December–March.
Etymology.— The specific epithet refers to the limestone habitat.