Astiella longifimbria Groeninckx, 2017

Groeninckx, Inge, Janssens, Steven, Smets, Erik & Verstraete, Brecht, 2017, Description of 11 new Astiella (Spermacoceae, Rubiaceae) species endemic to Madagascar, European Journal of Taxonomy 312, pp. 1-40 : 27-29

publication ID	https://doi.org/ 10.5852/ejt.2017.312
DOI	https://doi.org/10.5281/zenodo.3846902
persistent identifier	https://treatment.plazi.org/id/039E3C56-5A37-FF9E-9D61-0720E18C0B7A
treatment provided by	Carolina
scientific name	Astiella longifimbria Groeninckx
status	sp. nov.

Treatment

Astiella longifimbria Groeninckx View in CoL sp. nov.

http://www.ipni.org/urn:lsid:ipni.org:names:77161724-1

Figs 2I View Fig , 13 View Fig

Diagnosis

Astiella longifimbria sp. nov. resembles A. homolleae sp. nov. in having long fimbriate stipules, but differs in having corolla lobes moderately covered with appressed trichomes (vs glabrous), and a welldeveloped corolla tube (vs reduced).

Etymology

The specific epithet refers to the long fringes of the stipules.

Type

MADAGASCAR: Mahajanga province, Sofia region, Bealanana district, Montagnes au nord de Mangindrano (haute Maevarano) jusqu’aux sommets d’Ambohimirahavavy (partage des eaux Mahavavy-Androranga: centre-nord), clairières naturelles en forêt ombrophile sur latérite de gneiss (berges) de la Bemafo affluent de l’Androranga, 1900 m, 19 Jan.–12 Feb. 1951, Humbert & Capuron 25168 (holo-: P; iso-: BR, P).

Description

Herb, up to 15 cm tall, rooting at the basal nodes; young stems quadrangular in cross section, lanate, with reddish brown multicellular trichomes up to 1 mm long, older stems glabrous. Stipule base 0.8–1.5 mm long, moderately covered with reddish brown appressed trichomes; fimbriae 2–4, 4– 6.5 mm long, beset with reddish brown trichomes. Leaves petiolate; petioles 3–11.5 mm long, lanate; blades ovate to elliptic, 12–50 × 5.5–23 mm, sparsely covered with appressed trichomes up to 0.5 mm long particularly on the midvein and in between the secondary veins above, sparsely covered with appressed trichomes up to 0.5 mm long particularly on the midvein and on the secondary veins below; base attenuate; apex acute or obtuse; margin revolute when dry, densely ciliolate; midvein prominent below; secondary veins 3–7 on each side of the midvein, prominent below; intersecondaries invisible. Inflorescences terminal, compound dichasia, several-flowered; peduncle 5–22.5 mm long, with indumentum similar to the stems. Pedicels 0.5–11 mm long, with indumentum similar to the stems. Flowers probably heterostylous (only flowers with anthers exserted and style included have been observed). Calyx green; tube reduced; lobes 4, narrowly ovate, 3.5–4.2 × 0.3–0.4 mm, densely pubescent. Corolla white or pale blue; tube funnel-shaped, 2.5–4.5 mm long, 0.6–0.9 mm wide at the base, 1.7–2 mm wide at the apex, moderately covered with appressed trichomes outside, densely covered with spreading trichomes inside; lobes 4, ovate, 2–4.5 × 1.2–1.3 mm, moderately covered with appressed trichomes outside, glabrous inside except for a ring of trichomes at the base. Stamens inserted near the base of the corolla lobes in presumed brevistylous flowers and exserted for 2.5–3 mm beyond the corolla throat. Anthers ellipsoid, 1.3–1.8 mm long; filaments dorsifixed, 1.5–2.3 mm long. Pollen unknown. Ovary 2-locular, broadly obpyramidal, 1–1.2 × 1 mm, densely covered with spreading trichomes up to 0.6 mm long; placenta attached above the middle of the septum, stalked, elongated, bearing numerous ovules per locule. Style ca 4 mm long and included in presumed brevistylous flowers; stigma bilobed, lobes ca 1.2 mm long, papillate. Capsules and seeds unknown.

Distribution

NW Madagascar: Mahajanga province, Sofia region, Bealanana district.

Habitat

Humid forest; laterite substrate; at 1900 m elevation.

Conservation status

Known from only one locality. Given its apparent rarity and following the recommendation of Callmander et al. (2005) to avoid the Data Deficient category, we consider the species as vulnerable (VU D2) based on its restricted area of occupancy (D2) and the high human pressure present in the entire area resulting in a general decline of suitable habitats (humid forest) for the species.