Croton rufolepidotus Caruzo & Riina (2010b: 248)

Caruzo, Maria Beatriz Rossi & Cordeiro, Inês, 2013, Taxonomic revision of Croton section Cleodora (Euphorbiaceae), Phytotaxa 121 (1), pp. 1-41 : 14

6. Croton rufolepidotus Caruzo & Riina (2010b: 248) ( Fig. 6A–H ). Type:— COLOMBIA. Antioquia: Tarazá, Corrigimiento El 12, camino El 12- Barroblanco , km 4 N. O. Medellín, 210 km en troncal del Caribe , bht/bmht, 7º30’N, 75º16’W, 25 May 1987, R. Callejas, J. Betancur & F.J. Roldán 3611 (holotype MO!, isotypes DAV!, HUA!) .

Trees 6–10 m tall; indument rufous-silvery, lepidote trichomes without a central ray, trichomes pale, reddish or sometimes with a reddish center and a pale margin; branchlets cylindric, smooth, rufous-silvery, covered by reddish and scattered pale trichomes. Leaves discolorous, with a pair of shortly stalked saucer-shaped basilaminar glands; lamina 3–11.5 × 1–4.5 cm, narrowly ovate to ovate-elliptic, apex narrowly acute to acuminate, base rounded to slightly cordate, margin entire, upper surface glabrate, lower surface densely lepidote, covered by pale trichomes and scattered reddish trichomes or trichomes with a reddish center and a pale margin; venation pinnate, brochidodromous; petiole 0.5–1.5 cm long; stipules 0.5–1.5 cm long, auriculate, apex caudate, deciduous. Inflorescences 2.5–6.5 cm long, terminal, lax; inflorescence axis cylindric, striate, lepidote; proximal cymules pistillate, with a single flower, distal cymules staminate, with 1– 2 flowers; bracts 3–5 mm long, entire, linear, prophylls inconspicuous. Staminate flowers 1–1.5 cm long, campanulate, pedicels ca. 6 mm long; calyx ca. 4 mm long, lepidote externally, rufous-silvery, covered by reddish and scattered pale trichomes, glabrate internally; calyx lobes 5, united up to half of their length, then free for ca. 2 mm, entire, equal, valvate, triangular, apex acute; petals ca. 4 mm long, spathulate, densely villose externally, apex with an uneven margin; disk 5-segmented; stamens 15–25, filaments subulate, anthers narrow ellipsoid; receptacle villose with simple trichomes. Pistillate flowers 1–1.5 cm long, flask-shaped, long pedicellate; pedicel 4–6 mm long; calyx 6–8 mm long, lepidote externally, rufous-silvery, covered by reddish and scattered pale subentire lepidote trichomes, glabrate internally; calyx lobes 5, united at the base, then free for the terminal 6–8 mm, entire, equal, quincuncial, ovate-lanceolate, apex acuminate, foliaceous, not fleshy; petals absent; disk entire, slightly 5-lobed; ovary subglobose, 3-angled, lepidote; styles 3, multifid, united at the base, then divided into three short columns about 1/3 to ½ of the stylar length, each one branching into 8 terminal arms, with a total of 24 arms, exserted from calyx. Fruits ca. 1.5 cm long, subglobose, 3-angled, smooth, lepidote, sepals inconspicuously accrescent; seeds not seen.

Distribution and habitat: — Croton rufolepidotus is endemic to Antioquia, Colombia, where it grows in lowland secondary forests, at 180–310 m elevation ( Caruzo et al. 2010b).

Phenology:— Flowering in May, July and November; fruiting in May, July and November.

Taxonomic notes: — Croton rufolepidotus can be distinguished from other C. section Cleodora species by its rufous-silvery leaves and auriculate stipules. It is most similar to C. salutaris , from the Atlantic rain forest of southeastern Brazil (São Paulo, Minas Gerais, Rio de Janeiro, and Espírito Santo states), but that species differs from C. rufolepidotus mainly by morphology of stipules and branchlets (see table 1).

Selected specimens examined: — COLOMBIA. Antioquia: Tarazá, Corregimiento El Doce, 210 km NNE of Medellín, Carretera El Doce-Barro Blanco , near entrance to Hacienda Las Mercedes , rd. outside of finca, 7º30’N, 75º16’W, fl., fr., 25 July 1987, W. W . Thomas & C.J. Castaño C. 5525 (COL, MO, NY) .

Figures

FIGURE 6. A–H. Croton rufolepidotus. A. Branch with flowers and fruits. B. Pistillate flower. C. Detail of the gynoecium. D. Fruit. E. Staminate flower. F. Petal of the staminate flower. G. Aestivation of the pistillate sepals. H. Aestivation of the staminate sepals. (Callejas et al. 3611; illustration from Caruzo et al. 2010b).