Conservation Status and Abundance of the Crowned Sifaka (Propithecus coronatus)

The crowned sifaka (Propithecus coronatus) is Endangered. It has a large but highly fragmented distribution; its known range extends from the Betsiboka River in the north of Madagascar, to the Mahavavy River in the north-west, and down to the Tsiribihina River in the south-west. The species lives in forest habitats that are highly and increasingly fragmented and are continuously suffering perturbations and destruction. In order to carry out effective conservation measures targeting P. coronatus, its conservation status needs to be updated so that measures can be taken before anthropogenic or natural environmental changes lead to the extirpation of the species in most of its forests. We (i) identified forest fragments where the species is still present and (ii) using the line-transect “Distance” sampling method, estimated the population size and density in the principal remaining forest fragments in the northern part of its range, including both protected and unprotected areas. We visited most of the forests in the northern part of its range in order to update the current area of occupancy, and to rate the state of its forests using a qualitative “forest quality index.” Our survey results have shown that (i) a large number of forests have disappeared or decreased in size in the last 10 years, and (ii) population densities vary considerably among forest fragments (ranging from 49 to 309 individuals per km²), with some very high densities in forests located along the Mahavavy River and in the Antrema area. Their abundance in the area surveyed is likely to be between 4,226 and 36,672 individuals, and most probably above 10,000. It is difficult to extrapolate from these estimates to the total abundance across the species’ entire range, but we estimate that it is likely to be large, probably between 130,000 and 220,000 individuals. Unfortunately, many field observations suggest that its populations continue to decline at a high rate due to habitat loss and hunting, and we argue for the re-evaluation of the conservation status from Endangered A2cd to Endangered A4acd, and the need to survey the rest of the range of P.coronatus.FCT grant: (SFRH/BD/64875/2009), Institut Français de la Biodiversité, Programme Biodiversité de l’Océan Indien (ref.CD-AOOI-07-003), the GDRI Madagascar, the "Laboratoire d’Excellence" (LABEX) entitled TULIP: (ANR -10-LABX-41), Instituto Gulbenkian de Ciência, “Optimus Alive!” Biodiversity grant, University of Mahajanga, Département de Biologie Animale et Ecologie, Fanamby NGO

Exacum alberti-grimaldii Wohlh. & Callm. 2012, spec. nova

<i>Exacum alberti-grimaldii</i> Wohlh. & Callm., spec. nova (Fig. 2-4). <p> <b>Typus: MADAGASCAR.Prov.</b> <b>Antsiranana:</b> Fkt. Andrafiabe, chaîne d’Andrafiamena, bassin-versant d’Ampantsona, falaises gréseuses en forêt de transition, 12°55’10”S 49°21’13”E, 650 m, 1.V.2007, fl. & fr., <i>Wohlhauser & Bongary 803</i> (holo- G [G0036900]!; iso-, K!, MO!, P [P00722549]!, TAN!).</p> <p> <i>Haec species quoad folia superiora verticillata etiam inflorescentiam</i> umbraculiformem Exaco dolichanthero et <i>E.nossibensi similis, sed ahoc sepalisexalatis, ab illo petalisdiscretisminoribus (2-3</i> Χ <i>1-1.5 vs 3-7</i> Χ <i>2-4mm) facile distinguitur.</i></p> <p> Annual erect <i>herb</i>, unbranched, 3-13 cm. <i>Stem</i> quadrangular, with inconspicuous membranous wings, without nodes (exceptionally 1 node), often with 2 cotyledons at base. Any parts of the plants may be reddish due to the presence of anthocyanin in shadow habitats. <i>Leaves</i> not amplexicaulous, (2-) 3 pairs, opposite-decussate, with generally sub-verticillate aspect, shape variable depending on plant size and position of leaves; proximal pair of leaves sometimes on a lower node on the stem or absent, broadly ovate, narrowly attenuate at base, obtuse (sometimes rhomboid, orbicular or obcordate), (5-)10 (-l5) Χ (2-)5(-7) mm, lamina herbaceous, with 1-3 nerves diverging from base; medium pair of leaves generally large, subsessile, cordate, (4-)15(-25) Χ (3-)10(-15) mm, lamina herbaceous, with 3-5(-7) nerves diverging from base; distal pair of leaves generally reduced, very variable in size, shape and color (reddish), ovate to lanceolate, (5-)20(-37) Χ (3-)10 (-28) mm, lamina herbaceous to membranaceous, with 1(-3) nerves diverging from base. <i>Flowers</i> (1-)5(-14) in umbel-shaped, generally simple condensed cymes inflorescences, if composed 7-15 flowers per umbellule; pedicels (15-)25(-36) mm, erect at maturity, possibly cleistogamous (then reflected below the leaves). <i>Calyx</i> 5-lobed, the lobes shortly fused at base (<1/5 of the length), 1.5-2.5 mm, linear, not winged, acuminate, accrescent in fruit. <i>Corolla</i> 5-lobed, light blue, white in throat, fused in the lower fourth, 2-3 Χ 1-1.5 mm, obovate, obtuse, acuminate, when withered with lobes forming a cone at the top of the capsule, accresent. <i>Stamens</i> 2-3 mm long; anthers c. 1 mm, yellow, rectangular, curved and slightly narrowing towards the apex, without papilla near the apex, opening by pores that later widen to slits along up to 1 / <b> 2</b> of the anther length. <i>Styles</i> as long as the stamens. <i>Fruit</i> a sub-spherical capsule, 1.5-2 mm in diam., coriaceous, with accresent sepals appressed to the distal part of withered corolla, septicidally 2-valved with the partial septum.</p> <p> <i>Etymology.–</i> The species is named in honour of Albert II de Monaco, Albert Alexandre Louis Pierre Grimaldi, Prince of Monaco, in recognition of his tireless support to the NGO Fanamby for their conservation activities in Northern Madagascar, especially in the Andrafiamena region where the species seems to be endemic.</p> <p> <i>Distribution and ecology. – Exacum alberti-grimaldii</i> is only known from the Ampantsona river watershed occurring on seeping sandstone outcrops or on temporary humid river banks in semi-deciduous or sclerophyllous forest. It is an annual species completing its life-cycle in less than two and half months between March and May.</p> <p> <i>Conservation status. – Exacum alberti-grimaldii</i> has been observed only three times in the Ampantsona valley and collected only once. With only one collection and three known subpopulations, an AOO of> 9 km 2 within the Protected Area under creation of Andrafiamena-Andavakoera and according to its annual life-cycle and rarity of proper habitats, <i>E.albertigrimaldii</i> is assigned a preliminary status of Vulnerable (VU D2) following IUCN Categories and Criteria (IUCN, 2001).</p> <p> <i>Notes. –</i> Only two other species are characterized by verticillated upper leaves and umbella-shape inflorescence: <i>E.dolichantherum</i> Klack. and <i>E.nossibense</i> Klack. (KLACKENBERG, 1985: 94; Fig. 69, 96, 71). <i>Exacum alberti-grimaldii</i> can be easily distinguished from <i>E.dolichantherum</i> by its smaller discrete petals (2-3 Χ 1.0- 1.5 mm vs 3-7 Χ 2-4 mm for <i>E. dolichantherum</i>) and from <i>E. nossibensee</i> by the absence of wings on the sepals (Fig. 2-4). The new species grows in a dry transition area on diverse substrates (limestone-sandstone) whereas <i>E.dolichantherum</i> grows in open areas on sand along the littoral of the east coast and <i>E.nossibensee</i> is endemic from the Sambirano Domain <i>sensu</i> HUMBERT (1955) on diverse substrates.</p>Published as part of <i>Wohlhauser, Sébastien & Callmander, Martin W., 2012, Exacum alberti-grimaldii Wohlh. & Callm. (Gentianaceae), a new species endemic to northern Madagascar, pp. 373-378 in Candollea 67 (2)</i> on pages 374-378, DOI: 10.15553/c2012v672a18, <a href="http://zenodo.org/record/5851610">http://zenodo.org/record/5851610</a&gt