Croton viridifolius J.Beyer, 2023
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publication ID |
https://doi.org/10.3767/blumea.2023.68.01.01 |
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persistent identifier |
https://treatment.plazi.org/id/4F6387C4-DF7E-E500-FCE7-FD55FEE63A3C |
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treatment provided by |
Felipe |
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scientific name |
Croton viridifolius J.Beyer |
| status |
sp. nov. |
16. Croton viridifolius J.Beyer View in CoL , sp. nov. — Fig. 2c View Fig , 7 View Fig
Unique on Sumatra are the small and narrow leaves (2.5–7.2 by 0.7–2.2 cm), the few (4–6) secondary veins, the light green colour after drying, the short inflorescences (only 0.5–2.5 cm long) and very narrow pistillate sepals. — Type: Kleinhoonte 460 (holo L [ L.2212218]!), Indonesia, Sumatera Barat, Sarasah Bunta .
Shrubs or trees; young branchlets densely pubescent, soon glabrescent. Indumentum consisting of whitish to yellowish brown stellate trichomes, 0.2–0.4 mm diam, flat, often with a short central porrect radius, with 15–25 free to slightly fused radii (occasionally completely fused on stems). Stipules triangular-ovate to ensiform, 0.6–2 by 0.2–0.8 mm, densely pubescent on both sides, caducous. Leaves alternate to apically crowded; petiole 0.3–1(–1.5) cm long, deeply grooved above, with scattered trichomes to slightly pubescent; glands as slightly stalked discs abaxially at the very base of the leaf ( Fig. 2c View Fig ), close to but almost never on the midrib base, diam 0.2–0.4 mm, stalk 0.1–0.2 mm long; blade narrowly elliptic, 2.5–7.2 by 0.7–2.2 cm, 2.4–4.2 times longer than wide, chartaceous, symmetric, base obtuse, margin entire, flat (to slightly revolute), without glands, apex acute to obtuse, adaxially initially with scattered trichomes (more dense near large veins), glabrescent, abaxially with scattered distinct trichomes, epidermis visible; venation distinct, basally slightly to not triplinerved, secondary veins 4–6 pairs. Inflorescences thyrsoid, solitary per apical node, unisexual, 0.5–2.5 cm long; bracts triangular-ovate, c. 0.5 by 0.5 mm, slightly pubescent, caducous. Staminate flowers c. 3 mm diam; pedicel 1– 2 mm long, round, subglabrous; sepals triangular-ovate, 1–1.5 by 0.5–1 mm, subglabrous outside, with a patch of simple trichomes on apex; petals ensiform, c. 1.8 by 0.3 mm, outside glabrous, lanate on margin and inside; stamens 10 or 11, free, filaments c. 1.5 mm long, anthers c. 0.4 by 0.5 mm, connective pilose. Pistillate flowers c. 3 mm diam; pedicel 1–2 mm long, sulcate, densely pubescent; sepals triangular, c. 1.4 by 0.8 mm, fused at the base, spreading at the apex, outside slightly pubescent (denser near base), with a patch of simple trichomes on apex, as high as to slightly shorter than ovary; petals absent; ovary 3-lobed, subglobose, c. 1.2 by 1.4 mm, densely yellowish pubescent; style absent; stigmas c. 2 mm long, fused at base, once divided to c. 1.6 mm from apex. Capsules unknown, columella c. 4.5 mm long. Seeds young, likely with small caruncle.
Distribution — Malesia: Endemic to Sumatra (Sumatera Barat).
Habitat & Ecology — Habitat unknown. Altitude: c. 500 m. Flowering and fruiting: only known from August.
Affinities — Riau pocket group ( Van Ee et al. 2015).
Notes — 1. Only known from one specimen, originally identified by Van Steenis as Croton verreauxii Baill. But the specimen shows limited to no similarity with the Australian specimens of C. verreauxii .
2. Most similar species are C. gageianus (also having short inflorescences and a narrow leaf blade) and C. simalurensis (due to similar indumentum and location of leaf glands) but C. viridifolius can easily be distinguished by the small leaves and few secondary veins.
3. The inflorescences appear as unisexual, but this is likely typical for this specimen.
| L |
Nationaal Herbarium Nederland, Leiden University branch |
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.