Croton spruceanus Bentham (1854: 375)

Caruzo, Maria Beatriz Rossi & Cordeiro, Inês, 2013, Taxonomic revision of Croton section Cleodora (Euphorbiaceae), Phytotaxa 121 (1), pp. 1-41 : 30-31

18. Croton spruceanus Bentham (1854: 375) ( Fig. 7G–M ). Type:— BRAZIL. Amazonas: Among inundated rocks at the falls of San Gabriel, January-August 1852, R. Spruce 2205 (holotype K!, isotypes A!, NY!, MO!, P!). Croton calycularis Huber (1914: 181) . Type:— BRAZIL. Pará: 'Hab. In silvis editis ad fl. Cumina-mirim', 13 December

1906, A. Ducke s.n. (holotype MG [7946]!, isotype RB!) .

Shrubs ca. 3 m tall; latex clear; stellate, appressed-stellate, stellate-lepidote and dendritic trichomes; branchlets cylindric, slightly striate, floccose, dendritic trichomes. Leaves discolorous, with a pair of sessile saucershaped orange basilaminar glands; lamina 4–16 × 0.7–8.5 cm, elliptical to ovate, rarely ovate-lanceolate, apex acuminate to long acuminate, base rounded, margin inconspicuously serrate, with glands; upper surface glabrescent, simple trichomes, stellate trichomes on midvein, lower surface pubescent, chalky, pale appressedstellate porrect trichomes; venation pinnate, brochidodromous; petiole 0.3–2.5 cm long; stipules subulate, ca. 3 mm long. Inflorescences 4–18 cm long, terminal, lax; inflorescence axis slightly flattened, striate, floccose, dendritic trichomes; proximal cymules bisexual, with 1 pistillate flower and 1 staminate flower, distal cymules with 1 staminate flower; bracts ca. 2 mm long, entire, linear-lanceolate, prophylls inconspicuous. Staminate flowers 0.6–1cm long, campanulate, pedicellate; pedicels 1–4 mm long; calyx ca. 4 mm long, pubescent externally, ferrugineous, appressed-stellate and stellate-lepidote trichomes, glabrate internally; calyx lobes 5, united up to half of their length, then free for ca. 2 mm, entire, equal, inconspicuously imbricate, ovate to triangular, apex acute, margin villose; petals ca. 5 mm long, elliptical to oblong, apex obtuse to rounded, wavy, villose externally; disk 5-segmented; stamens ca. 15, filaments subulate, villose at the base, anthers ellipsoid; receptacle villose with simple trichomes. Pistillate flowers ca. 1.1 cm long, urn-shaped, pedicellate; pedicels ca. 4 mm long; calyx ca. 7 mm long, pubescent externally, ferrugineous, appressed-stellate and stellatelepidote trichomes, glabrate internally; calyx lobes 5, united almost at the apex, then free for ca. 1 mm long, entire, equal, inconspicuously imbricate, ovate, apex acute; petals absent; disk entire, flatly 5-lobed; ovary globose, appressed-stellate and stellate-lepidote trichomes; styles 3, 4-fid, united at the base, each one entire up to almost in their entire length, then branching into 12 terminal arms, covered by appressed-stellate and stellate-lepidote trichomes, included in calyx. Fruits ca. 1.8 cm long, subglobose, slightly warty, trichomes appressed-stellate and stellate-lepidote trichomes, calyx lobes conspicuously accrescent, inflated in young fruit, revolute in mature fruit; seeds ca. 6 mm long, ellipsoid, ribbed.

Distribution and habitat: —It occurs in Ecuador, Colombia, Venezuela, Bolivia and Brazil, in “terra firme” and flooded forests of the Amazon and Andean regions, growing from 50 to approximately 1800 m elevation.

Phenology:— Flowering in January–June and August–December; fruiting in February–June, August– October and December.

Taxonomic notes: — Croton spruceanus can be recognized in the field by its discolorous leaves, facing down, besides its erect inflorescences and pistillate calyx lobes conspicuously accrescent and inflated in young fruit.

Selected specimens examined: — COLOMBIA. Cauca: Cali, Villa Carmelo , 1700 m, fl., fr., 15 May 1982, H. Murphy 393 (COL, NY, US) . VENEZUELA. Zulia: Lagunillas, cuenca del Embalse Burro Negro (Pueblo Viejo), laderas occidentales de la Serrania de Ziruma o El Empalado , a lo largo del río Grande , unos 13 km al norte del Embalse , aprox. Lat. 10°25’N., Long. 70°49’O., en bosque siempreverde original, 550–600 m., 1–5 April 1982, G.S. Bunting et al. 11184 (HERZU, NY) . BRAZIL. Pará: Capanema, rio Quatipuru , in vicinity of Mirasselvas , ca. 30km by road west of Bragança , elev. 50m, ca. 1°04’S e 46°59’W, fr., 9 April 1980, G. Davidse et al. 18100 (DAV, INPA, MG, MO, NY, US) . ECUADOR. Morona-Santiago: La Mision, Salesiano, 5 km al S del Rio Bomboiza y cerca la carretera Zamora-Gualaquiza , 800 m, fl., fr., 31 October 1985, M.A. Baker & J. Zaruma 6493 ( MO) . BOLIVIA. Velasco, Parque Nacional Noel Kempff Mercado , a 15 km Del Campamento Los Fierros, 14°37’02’’S, 60°50’05’’W, 200 m, fr., 3 March 1997, S. Jimenez et al. 1127 (DAV, MO, USZ) .

Figures

FIGURE 7. A–F. Croton salutaris. A. Flowering branch (Pifano & Castro, 327). B. Pistillate flower, detail of calyx indument (Pifano & Castro 327). C. Gynoecium (Pifano & Castro 327). D. Reduced pistillate petal (Pifano & Castro 327). E. Stamen, dorsal and ventral views (Pifano & Castro 327). F. Fruit (Caruzo et al. 81). G–M. Croton spruceanus. G. Flowering branch (Caruzo & Riina 101). H. Bract (Caruzo & Riina 101). I. Pistillate flower (Caruzo & Riina 101). J. Gynoecium (Caruzo & Riina 101). K. Staminate flower (Caruzo & Riina 101). L. Fruit covered by inflated calyx lobes (Caruzo & Riina 101). M. Fruit (Caruzo & Riina 101).