Acalypha hispida Burm.f.

Muñoz, Iris Montero, Levin, Geoffrey A. & Cardiel, José María, 2023, Monograph of Acalypha L. (Euphorbiaceae) of the Western Indian Ocean Region, with the description of a new species from Mayotte, Adansonia (3) 45 (26), pp. 395-496 : 441

19. Acalypha hispida Burm.f.

Flora Indica 303, pl. 61, f. 1 ( Burman 1768). — Ricinocarpus hispidus (Burm.f.) Kuntze, Revisio Generum Plantarum 2: 618 ( Kuntze 1891). — Type: Habitat in India. Burman 1768: 302, table 61.

ICONOGRAPHY. — André (1898: 227); Hooker (1899: t. 7632).

ETYMOLOGY. — The epithet refers to the long and laciniate styles of the pistillate inflorescence according Sagun et al. (2010), or perhaps to the hispid surface of the ovary.

DISTRIBUTION AND HABITAT. — Cultivated species in Madagascar (Anosy) and Seychelles ( Mahé) ( Fig. 34 ).

PRELIMINARY CONSERVATION ASSESSMENT. — Acalypha hispida is widely cultivated in warm areas worldwide and not known in the wild; it sometimes escapes and is found along forest edges and roads. We assess A. hispida as Least Concern (LC).

MATERIAL EXAMINED. — 3 collections. Madagascar. Seligson, D. 652 ( GH [GH01097235]). Seychelles. Hein, G. 10 ( GH [GH01097236]); Jeffrey, C. 599 (K).

REFERENCES. — Bojer (1837: 25); Baillon (1861: 274); Palacký (1907: 25); Robertson (1989: 199); Montero Muñoz et al. (2018a: 99).

DESCRIPTION

Shrubs or subshrubs, probably evergreen, to 4 m tall, possibly dioecious, only female plants known. Branches tomentose and short-hispid, glabrescent when mature. Axillary buds naked, densely pubescent with simple, short trichomes. Stipules to 1 cm long, triangular-lanceolate, appressed-pubescent. Petioles (2-) 4-11 cm long, indumentum similar to that on young branches, glabrescent. Leaf blades not variegated, (8-)10-17(-19) × (5.5-)7-10(-13) cm, usually ovate to elliptic-lanceolate, sometimes subrhombic, membranous; base usually rounded, sometimes subcuneate to subcordate; apex acute to subacuminate, acumen to 5 mm long, obtuse, mucronate; margin serrate to crenate-serrate, teeth acute or obtuse, sometimes slightly callose-edged; upper and lower surfaces subglabrous, with some sparse, simple trichomes on veins; venation actinodromous, basal veins 5 or 7, secondary veins 7-9 per side. Stipels absent. Inflorescences spiciform, unisexual, axillary. Male inflorescences unknown. Female inflorescences pendulous, densely flowered, to 40 cm long; peduncle to 30 mm long, pubescent with simple, curved trichomes; bracts numerous, sessile, not enlarging in fruit, to 1 mm long, elliptic-lanceolate, sparsely hairy and ciliate; margin entire; bracteoles absent. Male flowers unknown. Female flowers 4-6 per bract, sessile; sepals 3-4, to 1 mm long, triangular-lanceolate, ciliate; ovary c. 1 mm diameter, 3-lobed, smooth, surface densely hispid; styles 3, to 8 mm long, distinct, glabrous, each divided into 6-16 segments. Allomorphic flowers not seen. Capsules and seeds not seen.

NOTE

This shrub, native to Melanesia or Malesia ( Sagun et al. 2010), is frequent in gardens throughout the tropics and rarely appears naturalized. As all plants are pistillate, it can only reproduce clonally.We found collections from Madagascar and Seychelles where it is cultivated. It has been reported from Madagascar ( Palacký 1907), Mauritius ( Bojer 1837; Baillon 1861), La Réunion ( Baillon 1861: 274) and the Seychelles ( Robertson1989).

Figures

FIG. 34. — Distribution map of Acalypha hispida Burm.f. in Madagascar and Seychelles.