Astiella antsalovansis Groeninckx & Janssens & Smets & Verstraete 2017, sp. nov.
Creators: name: Groeninckx, Inge
name: Janssens, Steven
name: Smets, Erik
name: Verstraete, Brecht
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Gentianales
Rubiaceae
Astiella
Astiella antsalovansis

description: Astiella antsalovansis Groeninckx sp. nov.
http://www.ipni.org/urn:lsid:ipni.org:names:77161713-1
Figs 2B, 3, 4A, 5 A–B
Diagnosis
Astiella antsalovansis sp. nov. resembles A. pulla sp. nov. in having black seeds with a reticulate seed coat surface consisting of 5- to 6-angular testa cells and in having a ring of trichomes inside the corolla tube, but differs in the slender inflorescence axes (vs more robust), 3 ovules per locule (vs 4 to 5 ovules per locule), and a shorter style that is included in brevistylous flowers (vs exserted), and fruits 1–2 × 1.5–3 mm (vs 1.5–3.4 × 2.6–4 mm).
Etymology
The specific epithet refers to the Antsalova district where representative specimens were collected.
Type
MADAGASCAR: Mahajanga province, Melaky region, Antsalova district. Antsalova, 23 Feb. 1959, Botoalina 10301-RN (holo-: P; iso-: BR).
Additional material examined
MADAGASCAR: Mahajanga province, Melaky region, Antsalova district. Antsingy d’Antsalova, RN 9, en sous bois de forêt tropophile sur calcaire, Jan. 1975, Morat 4805 (P, TAN); 14 km ouest de Antsalova, sur dalle rocheuse en sous-bois, 17 Mar. 1993, Villiers, Klackenberg & Badre 4788 (P); 12 km ESE Ankiliromotsy, 26 km SE Antsalova, sous couvert forêt tropophile, 30 Mar. 1993, Villiers, Klackenberg & Badre 4996 (P).
Description
Annual herb, erect, up to 30 cm tall; stems quadrangular in cross section, only sparsely branching, glabrous or scabrate particularly at the nodes. Stipule base 0.5–1 mm long, puberulent; fimbriae 4–6, 0.1–0.4 mm long, colleter-tipped. Leaves petiolate; petioles 1–15 mm long, glabrous or scabrate; blades narrowly ovate to ovate, 10 –60 × 3.5–30.5 mm, glabrous or sparsely to densely scabrate particularly on the veins and towards the margin; base attenuate; apex acute; midvein prominent particularly below; secondary veins 3–6 on each side of the midvein, prominent below; intersecondaries visible. Inflorescences terminal or pseudo-axillary, lax compound dichasia, multi-flowered, resembling a scorpioid cyme, rarely axillary and then few-flowered and compact; peduncle 0–56 mm long, glabrous or scabrate; inflorescence axes slender. Pedicels absent or 0.5–2 mm long, glabrous or scabrate. Flowers heterostylous. Calyx green; tube reduced; lobes 4, triangular, 1–2 × 0.2–0.5 mm, sparsely to densely scabrate or covered with long trichomes, particularly on the margin. Corolla white, pale pink in the throat; tube funnel-shaped, 0.9–1.5 mm long, 0.4–0.6 mm wide at the base and 0.5–0.8 mm wide at the throat, with a few trichomes outside, with a ring of trichomes inside; lobes 4, ligulate, 1.3–1.6 × 0.5–0.6 mm in brevistylous flowers, 0.8–1.2 × 0.4–0.5 mm in longistylous flowers, glabrous outside, covered with trichomes inside. Stamens inserted near the base of the corolla lobes and exserted for ca 1 mm beyond the corolla throat in brevistylous flowers, inserted in the lower half of the corolla tube and included or only the apices exserted in longistylous flowers. Anthers ellipsoid, 0.7–1 mm long; filaments dorsifixed, ca 0.5 mm long in brevistylous flowers, 0.3–0.4 mm long in longistylous flowers. Pollen 7-colporate, suboblate; E 32–33 μm; P 28–31 μm; ectocolpi short; endocolpi short; tectum aperforate, granulate. Ovary 2-locular, broadly obpyramidal, 0.4–0.7 × 0.4–0.5 mm, glabrous or with a few trichomes; placenta attached near the middle of the septum, stalked, globose, bearing 3 ovules per locule. Style 1–1.2 mm long and included in brevistylous flowers, 1.8–2 mm long and exserted for 0.7–0.8 mm beyond the corolla throat in longistylous flowers, glabrous; stigma bilobed, lobes 0.2–0.3 mm long, papillate, pale blue. Capsules broadly depressed obovoid, 1–2 × 1.5–3 mm, crowned with the persistent calyx lobes, glabrous, dehiscence loculicidal. Seeds 1 per locule, elliptic in outline, ventral groove absent, 0.7–1 × 0.5–0.6 mm, black; seed coat surface reticulate, 5- to 6-angular testa cells, microsculpturing verruculate, central pit in tangential wall.
Distribution
W Madagascar: Mahajanga province, Melaky region, Antsalova district.
Habitat
Western humid and sub-humid forest; calcareous or rocky substrate.
Vernacular name
Masonkary.
Conservation status
The species is known from four localities from the Antsalova district. It is probable that the species grows within the Tsingy de Bemaraha National Park. The extent of occurrence is estimated between 100 and 5,000 km 2. The area of occupancy is estimated between 10 and 500 km 2. The number of locations is two: i.e. populations within the protected area and populations outside the protected area. The human pressure on the environment within the region is very high. A decline in the extent of occurrence, area of occupancy, and area, extent, and/or quality of habitat is therefore very likely. The species is therefore considered endangered: EN B1ab(i,ii,iii)+2ab(i,ii,iii).
description: Published as part of Groeninckx, Inge, Janssens, Steven, Smets, Erik & Verstraete, Brecht, 2017, Description of 11 new Astiella (Spermacoceae, Rubiaceae) species endemic to Madagascar, pp. 1-40 in European Journal of Taxonomy 312 on pages 7-11, DOI: 10.5852/ejt.2017.312, http://zenodo.org/record/3827336