Acalypha berryi, Muñoz & Levin & Cardiel, 2023

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 : 423

6. Acalypha berryi

I.Montero, Cardiel & G.A.Levin, sp. nov.

Acalypha berryi I.Montero,Cardiel & G.A.Levin , sp.nov. is morphologically most similar to A. lamiana (Leandri) I.Montero & Cardiel , A.pervilleana Baill. , and A. richardiana Baill. , but can be distinguished from all three by having stipules to 3 mm long (vs to 6-10 mm long); leaf blades with obtuse apices and glabrous lower surfaces (vs acute to acuminate or caudate apices and lower surfaces at least sparsely hairy); glabrous androgynous inflorescence rachises (vs at least sparsely hairy); glabrous male bracts (vs with hairs on the surfaces and/or margins); mature female bracts to 4 × 3.5 mm (vs to (6-)7-10 × 6-12 mm, or sometimes to 20 × 22 mm in A. pervilleana ); and bracteoles to 0.25 mm long (vs bracteoles absent).

TYPE. — Mayotte. Grande Terre , Tsingoni , Bord de la mangrove de Tsingoni (Mangrove de Mroalé), 11.X.2004, F. Barthelat, V. Guiot & G. Viscardi 1361 (holo-, MAO [02149]; isotypes: K, MO [MO-2966197], P [P00631024]) .

ICONOGRAPHY. — Fig. 18.

ETYMOLOGY. — The epithet honors Dr. Paul E. Berry, who has contributed extensively to our understanding of the systematics of Euphorbiaceae , especially of Croton and Euphorbia , and has worked extensively in Madagascar.

DISTRIBUTION AND HABITAT. — Endemic to Mayotte (Tsingoni). Edge of a mangrove swamp. Sea level ( Fig. 19 ).

PRELIMINARY CONSERVATION ASSESSMENT. — Acalypha berryi sp. nov. is only known from one collection made near the Tsingoni Mangrove swamp on Mayotte and it is not a common species in the area (Fabien Barthelat pers. com.). Its EOO could not be calculated; its AOO is estimated to be 8 km 2. The mangrove swamp of Tsingoni, which has high species richness and high heritage value, was selected by the French association “Conservatoire du Littoral” in 1997 to be protected (IUCN category IV). Despite that protection, the swamp has lost about 3% of its surface from 1997 to 2020. In addition, the Ylang-Ylang plantations are affecting the area near the swamp ( Dudley 2008; Abdallah & Eymard, 2012; Barthelat 2019; Jeanson et al. 2019; UNEP-WCMC 2022). Acalypha berryi sp. nov. is assessed, preliminarily, as Critically Endangered: CR B2ab(ii,iii,iv).

MATERIAL EXAMINED. — 1 collection. Mayotte: Barthelat, F. 1361 (K, MAO[MAO02149], MO[MO-2966197], P[P00631024]).

DESCRIPTION Shrubs, probably deciduous, height unknown, monoecious. Branches glabrous. Axillary buds ovoid, to 1 mm diameter,

perulate; perules 2, imbricate, chartaceous, brownish, glabrous. Stipules to 3 mm long, triangular-lanceolate, apex acuminate,

sparsely hairy with some simple trichomes on midrib and apex. Petioles canaliculate, 2-3.5 cm long, pubescent with simple,

curved, antrorse trichomes, glabrescent. Leaf blades (4-)5-7 × 2-2.5(-3)cm, ovate-lanceolate to oblong-lanceolate,chartaceous; base rounded to subcordate; apex obtuse; margin denticulate,

revolute, slightly reddish; teeth minute, with a gland at apex; upper surface glabrate, with some simple, short trichomes at base; lower surface glabrous; venation actinodromous, basal veins 3, secondary veins (4-)5-6 per side. Stipels glandular,

0.2 mm long, glabrous. Inflorescences spiciform, androgynous, and solitary female bracts, axillary. Androgynous inflorescences to 2 cm long, mostly male with 1 female bract; sessile; rachis glabrous. Female segment: bract 1, sessile, enlarging in fruit to 4 × 3.5 mm, subtriangular to suborbicular, subglabrous, with some sparse, simple trichomes, especially near base; margin subentire to very sparsely and shallowly crenate, reddish, slightly thickened, teeth c. 5, rounded, ending in sessile gland, central tooth not prominent; bracteoles to 0.25 mm long, triangular, glabrous, with some sessile glands. Male segment persistent, to 2 cm long; flowers glomerate; bracts to 0.5 mm long, broadly triangular,glabrous. Solitary female bracts sessile, similar to those of androgynous inflorescence. Male flowers: pedicel to 0.5 mm long, sparsely hairy;buds to 0.5 mm diameter,glabrous. Female flowers 1 per bract, sessile; sepals 3, to 0.5 mm long, triangular, glabrous, margin with some sessile glands; ovary c. 1 mm diameter, 3-lobed, papillose-hispid, papillae minute, ending with simple, rigid trichomes to 1 mm long, surface glabrous, with some sessile glands; styles 3, to 3.5 mm long, distinct, glabrous, each divided into c. 5-6 segments. Allomorphic flowers not seen. Capsules not seen. Seeds not seen.

NOTE

Six other species of Acalypha are known from Mayotte: A. chibomboa , A. indica , A. lanceolata , A. mayottensis , A. pervilleana , and A.richardiana . Among these, Acalypha berryi sp. nov. is morphologically most similar to A. pervilleana and A.richardiana but can be distinguished using the characters given in the diagnosis.

Figures

FIG. 18. — Acalypha berryi I.Montero, Cardiel & G.A.Levin, sp. nov.: A, flowering branch with young leaves; B, detail of an inflorescence; C, detail of lower leaf surface and margin; D, mature female bract; E, calyx of the female flower; F, ovary and styles. Based on F. Barthelat, V. Guiot & G. Viscardi 1361. Illustration by Laura González Hernández. Scale bars: A, 1 cm; B, 0.35 cm; C, 0.5 cm; D, 1 mm; E, F, 0.5 mm.

FIG. 19. — Distribution map of Acalypha berryi I.Montero, Cardiel & G.A.Levin, sp. nov. in Comoros Archipelago.