Acalypha nusbaumeri I.Montero & Cardiel, 1169

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 : 465

37. Acalypha nusbaumeri I.Montero & Cardiel

PhytoKeys 140: 69 ( Montero Muñoz et al. 2020b). — Type: Mada - gascar. Reg. Sava [Prov. Antsiranana], sous-préfecture de Vohemar, commune rurale de Daraina, forêt de Bekaraoka, partie nord, 13°06’S, 49°42’E, 177 m, 13.II.2004, L. Nusbaumer & P. Ranirison LN1169 (holo-, G[G00028080]; iso-, K, MO, P[P01152829, P05547228]). ICONOGRAPHY. — Montero Muñoz et al. (2020b); Figs 57H ; 69A. ETYMOLOGY . — The epithet honors Louis Nusbaumer, researcher and curator at the Conservatoire et Jardin botaniques de la Ville de Genève, Switzerland. Nusbaumer works on the systematics, phylogeny, biogeography, and conservation of Malagasy plants and is also the collector, with Patrick Ranirison, of the type specimen of this species.

DISTRIBUTION AND HABITAT. — Endemic to Madagascar (Sava). Mainly in dry deciduous forest. On basement rocks. Altitudinal range 200-351 m ( Fig. 58 ).

PRELIMINARY CONSERVATION ASSESSMENT. — Acalypha nusbaumeri is only known from one collection from Loky-Manambato site (see assessment of A. menavody ). Its EOO could not be calculated; its AOO is estimated to be 8 km 2. Acalypha nusbaumeri is assigned a preliminary conservation status of Critically Endangered: CR B2ab(ii,iii).

MATERIAL EXAMINED. — 1 collection. Madagascar: Nusbaumer, L. LN 1169 (G[G00028080], K, MO, P[P05547228, P 01152829]) .

DESCRIPTION

Shrubs, probably deciduous, to 0.8 m tall, divaricately branched, monoecious. Branches blackish, pubescent with simple, curved, antrorse trichomes, glabrous when mature. Axillary buds spherical, to 1 mm diameter, perulate, perules 2, imbricate, membranous, brownish, external perule dentate, sparsely hairy. Stipules to 2 mm long, triangular-lanceolate, midrib prominent, sparsely hairy with simple, short, erect trichomes. Petioles slender, 2-3.5(-4.5) cm long, indumentum similar to that on young branches. Leaf blades 5-8.5 × 2.5-5 cm, ovate-lanceolate to elliptic-lanceolate, thin-membranous; base obtuse to rounded; apex subacuminate, acumen to 0.5 mm long, rounded, mucronate; margin crenate-serrate, teeth rounded; upper and lower surfaces subglabrous, with some simple, short, curved, antrorse trichomes on veins; axils of secondary veins with sparsely hairy, pocket-shaped domatia; venation actinodromous, basal veins 3 or 5, secondary veins 3-4 per side. Stipels absent. Inflorescences spiciform, androgynous, axillary, to 1.7 cm long, mostly male with 1 female bract at base; peduncle thick, to 5 mm long, indumentum similar to that on young branches. Female segment: bract 1, sessile, enlarging in fruit to 2 × 2.5 mm, orbicular-reniform, translucent, subglabrous, with simple, short trichomes on teeth and veins; margin crenate, central tooth not prominent; bracteoles to 0.5 mm long, linear-lanceolate, sparsely hairy with simple, short trichomes, margin with some sessile glands. Male segment persistent, to 0.7 cm long; bracts to 0.5 mm long, triangular, ciliate. Male flowers: pedicel to 0.5 mm long, sparsely hairy; buds c. to 0.8 mm diameter, glabrous, papillose. Female flowers 1 per bract, sessile; sepals 3, to 1 mm long, lanceolate, ciliate with simple, short trichomes; ovary to 1 mm diameter, 3-lobed, densely papillose, papillae minute, surface hispid; styles 3, to 3.5 mm long, distinct, sparsely hairy, each divided into 8-10 slender segments. Allomorphic flowers not seen. Capsules (immature) to 2 mm diameter, echinate, projections to 1 mm long, surface sparsely hairy with simple, short erect trichomes c. 0.5 mm long. Seeds too young to describe.

Figures

FIG. 57. — Mature female bracts: A, Acalypha leptomyura Baill. (J.-N. Labat & T. Deroin 2320); B, A. levinii I.Montero & Cardiel (L. Gillespie 10809); C, A. linearifolia Leandri (G. Cours 4638); D, A. magistri I.Montero & Cardiel (D. Ravelonarivo 273); E, A. mayottensis I.Montero & Cardiel (J.-N. Labat, F. Barthelat, C.M. Hladik & A.B. Sifary 3272); F, A. medibracteata Radcl.-Sm. & Govaerts (R. Decary 16103); G, A. menavody (Leandri) I.Montero & Cardiel (M. Bardot-Vaucoulon 1016); H, A. nusbaumeri I.Montero & Cardiel (L. Nusbaumer LN1169). Illustration by Iris Montero Muñoz. Scale bars: A, C, D, F, H, 1 mm; B, E, G, 2 mm.

FIG. 69. — A, Acalypha nusbaumeri I.Montero & Cardiel (photo by L. Nusbaumer, L. Nusbaumer LN1169); B, A. pervilleana Baill. (photo by L. Gillespie,L. Gillespie 10649); C, A. perrieri Leandri (photo by L. Gillespie, L. Gillespie 10835); D, A. radula Baker (photo by L. Gillespie, L. Gillespie 10758); E, A. rottleroides Baill. (photo by L. Nusbaumer, L. Nusbaumer 1933); F, A. spachiana Baill. (photo by L. Gillespie, L. Gillespie 10856); G, A. tremula I.Montero & Cardiel (photo by R. Randrianaivo, R. Randrianaivo 1160); H, A. urophylla Boivin ex Baill. (photo by L. Nusbaumer, L. Nusbaumer LN1663).

FIG. 58. — Distribution map of Acalypha nusbaumeri I.Montero & Cardiel in Madagascar.