Thursday, July 3, 2025

[Botany • 2025] A Synopsis of the Genus Jacquemontia (Convolvulaceae) in the Indo-Pacific with the Description of One New Species, Jacquemontia mohotaniensis


 Jacquemontia mohotaniensis Staples & Butaud,

in Staples, Butaud et Halford, 2025. 

Abstract 
Examination of specimens from the Marquesas Islands, French Polynesia, disclosed the presence of an undescribed species of Jacquemontia Choisy from the uninhabited island of Mohotani: the new species Jacquemontia mohotaniensis is described here and its conservation status is proposed as critically endangered. To place this novelty in context, a review of the native and naturalized Indo-Pacific taxa of Jacquemontia is provided; 14 names are accounted for and some taxonomic problems are highlighted for future study. New combinations are made for two Australian species, J. distigma (Benth.) Halford and J. flexuosa (Spreng.) Halford; a second step typification is provided for the latter name to stabilize the nomenclature.

KEYWORDS: biodiversity, Oceania, Marquesas, French Polynesia, Australia

 Jacquemontia mohotaniensis growth habit and plant parts.
(A) Habit showing flowers with fully reflexed corolla lobes and exserted genitalia; (B) flower with erect corolla lobes; (C) fruits, lateral view; (D) fruits, apical view, note 8 valves; (E) seeds in adaxial and abaxial views, note palisade of stiff hairs along margins and ventral keel, scale = 2 mm.
Photos A–D, J.-F. Butaud from living plants in DIREN; 
photo E, G. Staples, voucher: Butaud 4587 (A).

Jacquemontia mohotaniensis Staples & Butaud, sp. nov.

 TYPE: French Polynesia. Society Islands: ...

 DIAGNOSIS: Jacquemontia mohotaniensis resembles most closely J. paniculata but differs from that species in the larger flowers, 1.5–1.8 cm long and up to 1.9 cm in diameter, the corolla subsalverform, 5-lobed, pure white, with exserted stamens and stigmas (Figure 1). The unequal sepals, the outer 2 larger and covering the inner, narrowly ovate-elliptic and 6–8 mm long 2–2.5 mm broad (Figure 2) serve to distinguish this new species from all other known Jacquemontia.


G. Staples, Jean-François Butaud and David A. Halford. 2025. A Synopsis of the Genus Jacquemontia (Convolvulaceae) in the Indo-Pacific with the Description of One New Species. Pacific Science 78 (2), 153-163. DOI: doi.org/10.2984/78.2.3 (6 January 2025)