Acalypha fimbriata Schumach. & Thonn., 2277

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 : 437-438

16. Acalypha fimbriata Schumach. & Thonn.

Beskrivelse af Guineeiske Planter som ere fundne af dankse Botanikere, isaer af Etatsraad Thonning 409 ( Schumacher 1827). — Type: Ghana. s.l., s.d., P. Thonning s.n. (holo-, C [C10003279]; iso-, C[C10003278, C10003280], S[S14-42539]).

ICONOGRAPHY. — Oliver (1875: t. 96); Cardiel & Montero Muñoz (2018: 98); Fig. 35D.

ETYMOLOGY. — The epithet probably refers to the fimbriated-looking teeth margin of the female bracts.

DISTRIBUTION AND HABITAT. — Widely distributed in East and West Tropical Africa. Probably naturalized in Madagascar (Analamanga, Atsimo-Andrefana, and Ihorombe). Dry deciduous forest on limestone. 950-1000 m ( Fig. 31 ).

PRELIMINARY CONSERVATION ASSESSMENT. — Acalypha fimbriata is widely distributed in continental Africa, has a large EOO, a wide elevational range and occurs in many different ecosystems, and it is likely that its AOO exceeds the threshold of any threat category. Therefore, we assess A. fimbriata as Least Concern (LC).

MATERIAL EXAMINED. — 3 collections. Madagascar: Bosser, M.J. 17307 (P[P05547176]); Humbert , H. 14293 (P[P05547177]); Keraudren-Aymonin, M. 378 (P[P04779792]).

REFERENCES. — Montero Muñoz et al. (2018a: 98).

DESCRIPTION

Annual herbs, to 0.6 m tall, monoecious. Branches pubescent with simple, short, more or less appressed trichomes and sparse, simple, erect trichomes to 0.5 mm long, glabrescent when mature. Axillary buds naked, hispid with simple, erect trichomes. Stipules to 5 mm long, filiform, sparsely hairy. Petioles (2-) 3-6 cm long, sparsely hairy with simple, erect trichomes to 1.5 mm long and some simple, short, curved trichomes. Leaf blades 3.5-8.5 × 2-4.5 cm, ovate-lanceolate to elliptic-lanceolate, membranous; base acute to rounded, sometimes slightly cordate; apex acuminate, acumen to 15 mm long, acute, slightly callose; margin serrate, teeth subacute, slightly callose-edged, with a sessile gland at apex; upper and lower surfaces subglabrous, with simple, trichomes to 1 mm long; venation actinodromous, basal veins 3 or 5, secondary veins 5-7 per side. Stipels absent. Inflorescences spiciform, androgynous, axillary, to 3.5 cm long, mostly female with short male segment; peduncle to 5 mm long, pubescent with simple, curved, retrorse trichomes. Male segment persistent, to 0.7 cm long; flowers glomerate; bracts to 1 mm long, lanceolate, ciliate. Female segment to 2 cm long; bracts 8-15, sessile, enlarging in fruit to 8 × 11 mm, reniform, veins prominent, hirsute with slender, hyaline trichomes to 3 mm long and glandular trichomes to 0.5 mm long; margin dentate, teeth c. 23, falcate-lanceolate, central tooth not prominent; bracteoles absent. Male flowers: pedicel to 0.3 mm long, glabrous; buds to 0.5 mm diameter, glabrous, papillose. Female flowers 1 per bract, sessile; sepals 3, to 1 mm long, ovate-lanceolate, ciliate; ovary c. 1 mm diameter, 3-lobed, smooth, surface densely pubescent with simple, short trichomes; styles 3, to 4 mm long, distinct, glabrous, each divided into 2-3 segments. Allomorphic flowers sometimes present at inflorescence apex; pedicel filiform, to 5 mm long, pubescent with simple, curved trichomes and long hyaline trichomes to 3 mm long; sepals 3, to 0.5 mm long, triangular, ciliate; ovary 1-lobed, to 2 × 2.5 mm, pubescent with simple, short, flattened trichomes, distally fimbriate; style 1, to 2 mm long, glabrous. Capsules to 3 mm diameter, smooth, surface sparsely hairy. Seeds c. 2 × 1.2 mm, pyriform, minutely foveolate.

NOTE

Acalypha fimbriata was first reported for the WIOR by Montero Muñoz et al. (2018a).

Figures

FIG. 35. — Mature female bracts: A, Acalypha decaryana Leandri (R. Decary 2985); B, A. emirnensis Baill. (G. McPherson 14590); C, A. filiformis Poir. (P. Commerson s.n.); D, A. fimbriata Schumach. & Thonn. (J. Audru 40466); E, A. gillespieae G.A.Levin & I.Montero (L. Gillespie et al. 10692); F, A. gracilipes Baill. (R. Rabevohitra 2054); G, A. humbertii Leandri (W. Kaudern 222). Illustration by Iris Montero Muñoz. Scale bars: A, C-G, 1 mm; B, 2 mm.

FIG. 31. — Distribution map of Acalypha fimbriata Schumach. & Thonn. in Madagascar.