Friday, October 20, 2023

[Botany • 2023] Acalypha bardotiana & A. inaequibracteata (Euphorbiaceae: Acalyphoideae) • Two New Species from northern Madagascar


Acalypha bardotiana  I.Montero & Cardiel, 

in Montero-Muñoz, Levin, Lorenzo, González et Cardiel, 2023. 

Abstract
Background and aims – Taxonomic knowledge of Acalypha in the Western Indian Ocean Region (WIOR; including Madagascar, Comoros, Mascarenes, Seychelles, and the Scattered Islands) has increased greatly in the last few years. This paper is the latest in a series of publications that have contributed to create a robust taxonomic framework for Acalypha in this region.

Material and methods – The descriptions and illustrations of the new species are based on herbarium specimens and on some field images. Descriptions were made following standard procedures. Maps was prepared using QGIS software and preliminary conservation assessments was made following IUCN guidelines and criteria.

Key results – Two species of Acalypha from northern Madagascar are described as new to scienceAcalypha bardotiana sp. nov., found on the Montagne des Français (Diana region), and Acalypha inaequibracteata sp. nov., found in the Binara forest (Sava region). Line drawings, field images, distribution maps, and a discussion of their morphological and phylogenetic affinities, as well as the preliminary conservation assessments are provided.

Keywords: biodiversity, conservation, IUCN Red Listing, protected areas, taxonomy, WIOR

Acalypha bardotiana in situ.
A. Female inflorescence, leaves, and stipules. B. Habit.
Photos by Mrs Martine Bardot-Vaucoulon, used with permission.

Acalypha bardotiana.
 A. Habit. B. Detail of lower leaf surface. C. Detail of node, stipules, and petiole base. D. Mature female bract. E. Ovary and styles. F. Calyx of the female flower. G. Capsule. H. Seed.
Based on M. Bardot-Vaucoulon. G. Véné & G. Razafindrabelahasy 1209 (P and K). 
Illustration by Laura González Hernández.

Acalypha bardotiana I.Montero & Cardiel, sp. nov. 

Diagnosis: Acalypha bardotiana is morphologically close to A. lanceolata Willd. var. glandulosa (Müll.Arg.) Radcl.-Sm. but differs mainly by having a suffruticose habit and unisexual inflorescences (vs herbaceous habit and androgynous inflorescences), conspicuous stipules up to 8 mm long (vs inconspicuous stipules up to 2 mm long), petioles up to 8 mm long and leaf blades up to 9 cm long (vs petioles up to 4.6 mm long and leaf blades up to 6.5 cm long), and papillose-hispid capsules (vs smooth capsules).

Etymology: The epithet honours Mrs Martine Bardot-Vaucoulon, a French botanist who has conducted extensive botanical research in Madagascar. She is also one of the collectors of the type specimens of this species and kindly provided us with some field images included in this paper.


Acalypha inaequibracteata I.Montero & Cardiel, sp. nov.
 
Diagnosis: Acalypha inaequibracteata is morphologically similar to A. ankaranensis I.Montero & Cardiel, but differs mainly by having minute stipules up to 2 mm long, with simple trichomes (vs. stipules up to 5 mm long, with simple and glandular trichomes), petioles 0.5−1(–1.5) cm long (vs petioles 3−5 cm long), ovate to elliptic-lanceolate leaf blades that are rounded to obtuse at the base and lack domatia (vs broadly ovate-lanceolate leaf blades that are subcordate to cordate at the base and have pocket-shaped domatia), and dimorphic female bracts (vs monomorphic female bracts).

Etymology: The specific epithet refers to the presence of female bracts showing different shapes.


Iris Montero-Muñoz, Geoffrey A. Levin, Concepción Vaquero Lorenzo, Laura González, José M. Cardiel. 2023. Novelties in the Genus Acalypha (Euphorbiaceae, Acalyphoideae): Two New Species from northern Madagascar. Plant Ecology and Evolution. 156(3): 365-373. DOI: 10.5091/plecevo.108024