Croton cascarilloides Raeusch.

Beyer, J., Esser, H. - J., Eurlings, M. C. M. & Welzen, P. C. van, 2023, A revision of the genus Croton (Euphorbiaceae) in Sumatra (Indonesia), Blumea 68 (1), pp. 1-25 : 10-11

4. Croton cascarilloides Raeusch.

Croton cascarilloides Raeusch. (1797) 280; Merr. (1934) 60, non Geiseler (1807); (1935) 234; Croizat (1942a) 46; Airy Shaw (1963) 344; (1972a ‘1971’) 244; Whitmore (1973) 84; Airy Shaw (1975) 91; (1981a) 284;(1982a) 14; (1983) 18; Esser (2005) 197; B.T. Li & Esser (2008) 260. — Croton punctatus Lour. (1790) 581 (‘ punctatum ’), nom. illeg., non Jacq. (1786); Müll.Arg. (1866) 565; Gagnep. (1925) 290. — Lectotype (first step, appointing herbarium: Merrill 1935: 34; second step, appointing sheet, designated here): Loureiro s.n. (lecto BM [BM000926610]!; isolecto BM [BM000926609]!), Cochinchine (= southern Vietnam).

Croton polystachyus Hook. & Arn. (1838) 270, nom. illeg., non C. polystachyus Spreng.(1826) 868. — Type: Beechey s.n. (holo K [K000959133]*), Loo Choo Islands (Ryukyu Islands). Hooker & Arnott refer to Willdenow (meaning Sprengel) with a question mark, but as C. polystachus Spreng. (not polystachyus ) is from Brazil, the name is here considered as the introduction of a new name/species.

Croton cumingii Müll.Arg.(1865) 101;(1866) 566; Craib (1911) 463;(1912)190; Merr.(1923) 426;Ridl. (1924) 261; Gagnep. (1925) 264;M.R.Hend. (1939) 30, 70. — Oxydectes cumingii (Müll.Arg.) Kuntze (1891) 611. — Lectotype (designated here): Cuming 1384 (lecto G [G00434383]!; isolecto A [00099662] packet!, BM [BM000926594]!, E!, GDC [G00311739]!, GOET [GOET003339]!, [GOET003340]!, [GOET003341]!, K [K0009591761]!, [K000959177]!,KIEL!,L[L0016148]!,[L0062226]!,[L0062227]!,[L0062228]!, NY n.v., W 3 sheets!), Philippines, Luzon, Prov. Albay.

Croton cumingii Müll.Arg. var. angustifolius Gagnep. (1925) 264. — Lectotype (designated here): Poilane 1725 (lecto A [ A00105618 ]!; isolecto A [A[00105617 p.p.]!, BM!, E [ E00327461 ]!, K!, NY [00452493]!), Vietnam, Prov. Thanh-hoa, à La-han.

Croton pierrei Gagnep. (1922 ‘1921’) 558; (1925) 265. — Lectotype (designated here): Pierre 6233 (lecto P [P00109484]!; isolecto A [00072716]!,BM [000551499]*, as Pierre s.n., E [E00327460]!, G [G00358191]*, as Pierre s.n., GH [00099664]!, NY [00262986]!, as Pierre s.n, P [P00109485]!), Cochinchine,Prov.deTy-ninh,MontDeonba(perhapsalsoinK(K000959153)*, as Pierre s.n., but locality missing). Remaining syntypes: Harmand 631 (P!), Vietnam, Nui-cam; Thorel s.n. (A!, P!), Laos, La-khon.

Croton cascarilloides Raeusch. var. pilosus Y.T. Chang (1983) 171. — Type: ZX Zhang & SL Wang 4051 (holo KUN n.v.), China, Guangxi.

Shrubs or small trees, to 5 m tall, dbh to 12 cm; young branch-lets densely pubescent, hardly glabrescent. Outer bark thin, smooth, dark grey. Indumentum consisting of lepidote, hyaline trichomes with a yellow brownish centre to completely brown, scattered (on leaves) to dense (floral parts and stems), 0.3–0.6 diam, flat, circular, with c. 60–80 fused radii (less on adaxial side of leaf). Stipules ensiform, 3–6 by 0.5–1.2 mm long, densely pubescent on both sides, caducous. Leaves alternate in lower parts, pseudo-verticillate apically with 2–4(–6) leaves per ‘whorl’; petiole (0.5–) 1–5 cm long, sulcate, grooved above, densely pubescent; glands as flat discs lateral on the base of abaxial midrib, 0.4–1 mm diam, sessile; blade elliptic, (6–)8–22 by 2.5–8 cm, (2–)2.6–3.4 times longer than wide, chartaceous, base rounded to subcordate, margin entire, apex acuminate (occasionally acute to obtuse), adaxial side pubescent in young leaves to (sub)glabrous in old leaves, abaxial side completely and densely silvery-pubescent without visible surface, not glabrescent, scattered darker trichomes visible as distinct dots; venation with a very distinct main vein, sunken above, not triplinerved, secondary veins 9–15 pairs, higher order nerves very indistinct. Inflorescences 1(–2) per node, 0.5–2 cm long, densely brownish pubescent throughout, not glabrescent, with very few flowers, erect, basally 1– 3 pistillate flowers, apically 2 – 6 staminate flowers, the medium part sometimes with scars only (flowers caducous), staminate flowers never at the same node as a pistillate flower; bracts triangular, 1.5–3 by 1–1.5 mm, densely pubescent on both sides, eglandular, soon caducous. Staminate flowers c. 4 mm diam; pedicel 0.5–1.5 mm long, round, densely pubescent; sepals triangular-ovate, c. 2 by 1.5 mm, silverly brown to dark brown, completely pubescent; petals oblong, c. 2 by 1 mm, glabrous outside, lanate on margin and apex; stamens 11–16, free, filaments c. 1.5 mm long, anthers c. 1 by 0.5 mm. Pistillate flowers c. 5 mm diam; pedicel 1.5–3 mm long, round, densely pubescent; sepals elliptic, 2– 3 by 1–2 mm, densely pubescent, larger than ovary; petals absent; ovary globose, c. 1.5 by 2 mm, densely pubescent; styles less than 0.5 mm long; stigmas 3–3.5 mm long, fused at the very base, divided twice to 1–2 mm from apex. Capsules obovoid, clearly 3-lobed, almost as 3 individual capsules, 5–6 by 6–6.5 mm, sulcate, apex pressed inwards, densely pubescent; pericarp inside with scattered trichomes; columella 4–5 mm long. Seeds ellipsoid, 4.5–5.5 by c. 4 mm, slightly flattened, very rough, glabrous except for a few stellate trichomes near the attachment, with a small caruncle.

Distribution — Japan (Ryukyu Islands), Taiwan,S China, Thailand, Laos, Vietnam, Malesia: Malay Peninsula, Sumatra (Aceh, Sumatera Barat), Java, Borneo, Philippines, Sulawesi, Lesser Sunda Islands, Moluccas.

Habitat & Ecology — In primary dry evergreen or mixed evergreen/deciduous forest, bamboo-hardwood forest, secondary forest, on rocky slopes, hills, also along streambanks, usually shaded; collected on limestone, sandstone, clayey substrate. Altitude: sea level to 600 m. Flowering and fruiting the whole year through.

Affinities — The specimens present in our analysis and in that of Van Ee et al. (2015) showed a monophyletic species clade ( Fig. 1 : group H), part of a large polytomy with African, Asian, Australian and Pacific taxa. This species is not yet classified in any section, though Webster (1993) suggested either C. sect. Anisophyllum or C. sect. Monguia .

Uses — Bark and roots are used as an antipyretic ( Esser 2005).

Notes — 1. Only one specimen from Sumatra was with fruit, therefore Thai specimens were used for describing the capsules and seeds .

2. An isotype of C. vidalii Airy Shaw ( Vidal y Soler 555 in A [00100144]!) is C. cascarilloides , but the holotype (K [K000959255]*) and another isotype (L [L.2212494]!) are most certainly not C. cascarilloides and indeed C. vidalii .

Figures

Fig. 1 Bayesian phylogram based on ITS sequences excluding the 5.8S region. The values at nodes represent the Bayesian-inference posterior-probability support values. Astraea and Brasiliocroton are outgroups. Black names: New World, yellowish brown: Africa–Madagascar, green: mainland Asia, blue: Aus- tralia–West Pacific,red: Malesia.Accessions with bold names correspond to the newly sequenced taxa, all ocurring in Sumatra. Bar: nucleotide substitutions.