Description of 11 new Astiella (Spermacoceae, Rubiaceae) species endemic to Madagascar Author Groeninckx, Inge Plant Conservation and Population Biology, KU Leuven, Kasteelpark Arenberg 31, P. O. Box 2435, 3001 Leuven, Belgium. & Email: inge. groeninckx @ kuleuven. be inge.groeninckx@kuleuven.be Author Janssens, Steven Botanic Garden Meise, Nieuwelaan 38, 1860 Meise, Belgium. & Email: steven. janssens @ botanicgardenmeise. be steven.janssens@botanicgardenmeise.be Author Smets, Erik Naturalis Biodiversity Center, P. O. Box 9517, 2300 RA Leiden, The Netherlands. & Email: erik. smets @ naturalis. nl erik.smets@naturalis.nl Author Verstraete, Brecht Natural History Museum of Denmark, University of Copenhagen, Sølvgade 83 S, 1307 Copenhagen, Denmark. & Corresponding author: brecht. verstraete @ snm. ku. dk brecht.verstraete@snm.ku.dk text European Journal of Taxonomy 2017 2017-04-25 312 1 40 journal article 22142 10.5852/ejt.2017.312 561d2129-c2be-4670-9aa7-96e948247157 2118-9773 3827336 Astiella antongilensis Groeninckx sp. nov. http://www.ipni.org/urn:lsid:ipni.org:names:77161710-1 Figs 1 , 2A Diagnosis Astiella antongilensis sp. nov. resembles A. homolleae sp. nov. and A. perrieri sp. nov. in having a reduced corolla tube and numerous ovules per locule, but differs in having a pubescent stem, large leaves that are covered with trichomes below, and pubescent flowers. Etymology The epithet refers to Antongil Bay, the largest bay in Madagascar and the area where the species is found. Type MADAGASCAR : Toamasina province , Analanjirofo region, Maroantsetra district. Côte est, environs de la baie d’Antongil, bois, 200 m , Oct. 1912 , Perrier de la Bâthie 3749 (holo-: P , P 00219825; iso-: P , P 00516317). Description Annual herb, ca 10 cm tall; stems quadrangular in cross section, pubescent. Stipule base 1–2 mm long, pubescent; fimbriae 3–6, 1– 2 mm long, colleter-tipped. Leaves petiolate; petiole 5–15 mm long, pubescent; blades elliptic, slightly ovate or obovate, (12–)45–72 × (6–) 10–26 mm , very sparsely covered with trichomes particularly on the veins above, more densely covered with trichomes below; base attenuate; apex acute or obtuse; margin ciliolate; midvein prominent particularly below; secondary veins 4–7 on each side of the midvein; intersecondaries invisible. Inflorescences terminal, multi-flowered; peduncle 0–40 mm long, pubescent. Pedicels 1–7 mm long, pubescent. Flowers heterostylous (but both style and anthers exserted). Calyx green; tube reduced; lobes 4, narrowly triangular or triangular, 1–1.3 × 0.4–0.5 mm , pubescent. Corolla white or pale purple; tube reduced, 0.2–0.5 mm long; lobes 4, somewhat spathulate, 2.1–2.8 mm long, 0.5–0.6 mm wide at the base, 1–1.2 mm wide at the top, pubescent outside, papillate inside. Stamens inserted near the base of the corolla lobes and exserted for 2.2–3.2 mm beyond the corolla throat. Anthers ellipsoid, 1.2–1.4 mm long; filaments dorsifixed, ca 3.3 mm long in brevistylous flowers, ca 1.2 mm long in longistylous flowers. Pollen unknown. Ovary 2-locular, broadly obovoid, 1–1.2 × 1–1.3 mm , densely pubescent; placenta attached above the middle of the septum, stalked, elongated, bearing numerous ovules per locule. Style ca 3.3 mm long in longistylous flowers (exserted for ca 3 mm beyond the corolla throat), ca 2.5 mm long in brevistylous flowers (exserted for ca 2.2 mm beyond the corolla throat), glabrous; stigma bilobed, lobes 0.6–1 mm long, papillate. Capsules broadly obovoid or broadly depressed obovoid, 2.5–3 × 2.5–3 mm , crowned with the persistent calyx lobes, pubescent, dehiscence loculicidal. Seeds unknown. Fig. 1. Astiella antongilensis Groeninckx sp. nov. A . Habit. B . Brevistylous flower. C . Open brevistylous flower. D . Ovary dissected to show placentation. Drawn by Marijke Meersman. All from Perrier de la Bâthie 3749 (P). Fig. 2. Distribution maps. A . Astiella antongilensis Groeninckx sp. nov. B . A. antsalovansis Groeninckx sp. nov. C . A. confusa Groeninckx sp. nov. D . A. deblockiae Groeninckx sp. nov. E . A. delicatula Jovet. F . A. desseinii Groeninckx sp. nov. G . A. homolleae Groeninckx sp. nov. H . A. latifolia Groeninckx sp. nov. I . A. longifimbria Groeninckx sp. nov. J . A. perrieri Groeninckx sp. nov. K . A. pulla Groeninckx sp. nov. L . A. tsaratanensis Groeninckx sp. nov. Distribution E Madagascar : Toamasina province , Analanjirofo region, Maroantsetra district. Habitat Humid forest; at 200 m elevation. Conservation status The species is only known from its type collected in 1912. There is no detailed information about the locality where the specimen was collected. 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.