Acalypha leandrii I.Montero & Cardiel, 2037

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 : 452

26. Acalypha leandrii I.Montero & Cardiel

PhytoKeys 140: 61 ( Montero Muñoz et al. 2020b). — Type: Madagascar. Reg. Melaky [Prov. Mahajanga], Antsalova, vers Ambodiriana (E. d’Antsalova), 18°40’0.12”S, 44°43’59.879”E, 100-150 m, 06.XII.1952, J. Leandri, R. Capuron & A. Razafindrakoto 2037 (holo-, P[P05547059]). — Paratypes: Madagascar. Reg. Melaky [Prov. Mahajanga], calcaires de l’Antsingy, vers Andobo (E. d’Antsalova), en remontant vers Tsiandro, 18°40’0.12”S, 44°43’59.879”E, 5-8. II. 1960, 300 m, J. Leandri & P. Saboureau 2996 (K, MO[MO-3025001], P[P00324506, P05543680], TAN); J. Leandri & P. Saboureau 3016 (G!, MO[MO-2966304], P[P05547274]) .

ICONOGRAPHY. — Montero Muñoz et al. (2020b); Fig. 46F.

ETYMOLOGY. — The epithet honors French botanist Jacques Désiré Leandri (1903-1982).

DISTRIBUTION AND HABITAT. — Endemic to Madagascar (Melaky). Dry deciduous forest. On Mesozoic limestone. Altitudinal range 100-400 m ( Fig. 44 ).

PRELIMINARY CONSERVATION ASSESSMENT. — Acalypha leandrii is known from four collections from the Tsingy de Bemaraha. Its EOO could not be calculated; its AOO is estimated to be 8 km 2 (see assessment of A. cardielii ). No specimens of this species have been collected for 60 years, so we cannot rule out that this species has become extinct. Due to habitat loss, the restricted geographic range, and the absence of recent collections, A. leandrii is assigned a preliminary conservation status of Critically Endangered: CR B2ab(ii,iii), probably extinct (EX).

MATERIAL EXAMINED. — 4 collections. Madagascar. Leandri, J. 2037 (P[P05547059]), 2996 (K, MO[MO-3025001], P[P00324506, P05543680], TAN), 3016 (G, MO[MO-2966304], P[P05547274]); Keraudren-Aymonin, M. 511 (P[P04779527]).

DESCRIPTION

Herbs or sprawling subshrubs, probably evergreen, height unknown, probably dioecious. Branches densely pubescent with simple, short, curved, antrorse trichomes, glabrous when mature. Axillary buds ovoid, to 2 × 1 mm, perulate, perules 2, valvate, membranous, light brown, pubescent with simple, short trichomes. Stipules to 7 mm long, oblong-lanceolate, midrib prominent, margins scarious, midrib appressed-pubescent, margin ciliate with thin simple trichomes mixed with minute glands. Petioles 2-8 cm long, indumentum similar to that on young branches, glabrescent. Leaf blades 8-12 × (3.5-) 4.5-9 cm, broadly ovate-lanceolate, membranous; base rounded to cordate; apex acuminate to caudate, acumen to 25 mm long, acute, mucronate; margins serrate, teeth acute, slightly callose-edged; upper and lower surfaces laxly pubescent with simple, erect trichomes, and with short, curved, antrorse trichomes on veins; venation prominent in both surfaces, actinodromous, basal veins 3 or 5, secondary veins 7-9 per side. Stipels triangular, to 0.7 mm long, margin ciliate and with glandular trichomes. Inflorescences spiciform, unisexual, axillary. Male inflorescences to 8 cm long; peduncle to 20 mm long, indumentum similar to that on young branches; flowers glomerate; bracts to 1 mm long, lanceolate, margin ciliate and with sessile glands. Female inflorescences to 8.5 cm long; peduncle to 25 mm long, indumentum similar to that on young branches; bracts to 18, sessile, enlarging in fruit to 6 × 12 mm, subreniform, with prominent veins on upper surface, laxly pubescent with simple, erect trichomes and thick glandular trichomes to 1 mm long, margin entire; bracteoles absent. Male flowers: pedicel to 0.5 mm long, sparsely hairy; buds to 0.7 mm diameter, glabrous, papillose. Female flowers 1 per bract, sessile; sepals 3, to 1 mm long, oblong-lanceolate, ciliate with simple, erect trichomes to 0.5 mm long; ovary c. 1 mm diameter, 3-lobed, apparently smooth, surface densely hispid; styles 3, to 5 mm long, slightly connate at base, glabrous, each divided into 5 segments. Allomorphic flowers not seen. Capsules to 3 mm diameter, papillose-hispid, papillae to 0.5 mm long, ending in simple, erect trichome to 1 mm long, surface glabrous. Seeds pyriform 2 × 1.6 mm, minutely foveolate.

Figures

FIG. 46. — Mature female bracts: A, Acalypha indica L. (Sagun et al., 2010, Sagun & Risna SR58); B, A. integrifolia Willd. (P. Commerson 655); C, A. isaloensis I.Montero & Cardiel (J.-N. Labat 2119); D, A. lamiana (Leandri) I.Montero & Cardiel (H. J. Lam & A. Meeuse 6727); E, A. lanceolata Willd. var. glandulosa (Müll.Arg.) Radcl.-Sm. (H. Perrier de la Bâthie 9929); F, A. leandrii I.Montero & Cardiel (J. Leandri 2037); G, A. leonii Baill. (L. Gautier LG4003); H, A. lepidopagensis Leandri (H. Perrier de la Bâthie 9726). Illustration by Iris Montero Muñoz. Scale bars: 1 mm.

FIG. 44. — Distribution map ofAcalypha leandrii I.Montero &Cardiel in Madagascar.