131,156 research outputs found
Espèces nouvelles d' <i>Erythrina</i> et de <i>Mucuna</i> (Leguminosae-Papilionoideae-Phaseoleae) de Madagascar et des Comores
No full textL\u27étude des caractères morphologiques permet la description de trois espèces nouvelles d\u27Erythrina et une espèce nouvelle de Mucuna de Madagascar : Erythrina ankaranensis Du Puy & Labat, E. hazomboay Du Puy & Labat, E. madagascariensis Du Puy & Labat et Mucuna manongarivensis Du Puy & Labat.Morphological characters support the description of three new species of Erythrina and one new species of Mucuna from Madagascar: Erythrina ankaranensis Du Puy & Labat, E. hazomboay Du Puy & Labat, E. madagascariensis Du Puy & Labat and Mucuna manongarivensis Du Puy & Labat
D.-J. Wiseman.— The Alalakh Tablet
No full textLabat René. D.-J. Wiseman.— The Alalakh Tablet . In: Syria. Tome 31 fascicule 1-2, 1954. pp. 122-125
Ivodea mayottensis Labat & M.Pignal 2015
No full text19. Ivodea mayottensis Labat & M.Pignal, sp. nov. (Figs 6; 9 A-C) Haec species ab Ivodea choungiensi Labat, M.Pignal & O.Pascal inflorescentia calyce corolla staminibus ovario fructuque pubescentibus, foliis majoribus ad minimum 9,5 × 3,3 cm atque petiolo plus quam 1 cm longo distinguitur. TYPUS. — Mayotte. Grande Terre, Saziley Bé, [12°58’34”S 045°12’E], 30.VI.2008, fl. ♀, fr, Viscardi 47bis (holo-, P [P00696098]!; iso-, K!, MAO, MO!, P [P00722588]!). PARATYPES. — Mayotte. Grande Terre, Mtsamboro, Mlima Kétabé, [12°42’S 045°05’E], 18.IV.2007, fl. ♂, Barthelat & Viscardi 1813 (P [P00696099], MAO). — Même localité, 07.VII.2007, fr., Barthelat & Viscardi 1822 (MAO, MO, P [P00853170]). — Mêmes localité et date, fl. ♂, Barthelat & Viscardi 1823 (K, MAO, MO, P [P00853171]). — Même localité, 15.VII.2007, fl. ♀, fr., Barthelat & Viscardi 1826 (K, MAO, P [P00853172]). — Mêmes localité et date, fl. ♂, Barthelat & Viscardi 1827 (G, MAO, MO, P [P00853173]). — Même localité, 17.VII.2007, fl. ♂, Barthelat & Viscardi 1830 (K, MAO, MO, P [P00853174]). — Mêmes localité et date, fl. ♀, Barthelat & Viscardi 1831 (G, MAO, MO, P [P00853175]). — Saziley Bé, 24.VI.1999, [12°58’34”S, 045°12’E], fl. ♂, Mas 255 (P [P00176523]). — Mêmes localité et date, Mas 259 (G, K, MO, P [P00176524]). DESCRIPTION Arbre ou arbuste de 1,5-2 m, très ramifié. Rameaux glabres à écorce grisâtre, lenticelles présentes. Feuilles simples, alternes, ou subopposées à l’extrémité des rameaux, plutôt groupées dans la partie distale des branches; pétiole 0,4-1,2 cm de long, légèrement ou non ailé, canaliculé, glabre à sub-glabre; limbe glabre sur les deux faces, face adaxiale vert terne, face abaxiale à peine plus mate,rigide, mais peu coriace, elliptique à oblongelliptique, rarement légèrement obové, (3-)6-12 × (1,8-) 2,5- 4,5 cm, base longuement atténuée, marge entière à bord parfois révoluté, apex arrondi à obtus; nervure médiane saillante sur la face abaxiale, en creux sur la face adaxiale, vert clair à vert jaunâtre sur les deux faces sur le vif, nervures secondaires et tertiaires finement visibles sur les deux faces. Inflorescences terminales; les mâles en panicules, de forme générale pyramidale, d’environ 3-5,5 cm de long, pubescentes, avec une bractée à la base de chaque ramification, à groupes de cymes de 1 à 10 fleur(s), contractées, à l’aisselle de bractées triangulaires de 0,5 mm de longueur, persistantes; les inflorescences femelles identiques aux mâles, mais plus pauciflores et plus robustes, à groupes de cymes subsessiles de 1 à 3 fleur(s), longues de 2-9 cm; bractéoles 2 à la base de chaque fleur, ciliées, étroitement triangulaires. Boutons floraux femelles sphériques, avec 4 petites protubérances terminales. Fleurs femelles à pédicelle de moins de 1 mm de long; sépales cupuliformes à 4 lobes verts triangulaires peu marqués, pubescents; pétales blancs, 4 ou 5, lancéolés, pubescents. Fleurs mâles à sépales cupuliformes, à 4 lobes peu marqués, pubescents, ciliés à l’extrémité des pointes; pétales blancs 4, lancéolés, 2 × 1,5 mm, pubescents; étamines 4, 2 mm, filet pubescent, connectif et face dorsale des anthères hirsutes.Infrutescence terminale, en panicule ramifiée, 7-9 cm de long. Fruit à pédicelle trapu jusqu’à 3 mm, constitué de 4 à 5 follicules dont 2 à 4 sont souvent avortés; follicule sans sépales ni pétales persistants à la base, pubescent, d’environ 1,2 × 1,1 cm, brun jaunâtre à l’état jeune, en forme de coquille d’huître et à ornementation en ondulations concentriques peu marquées, valves s’ouvrant sur les ⅔ de la longueur. RÉPARTITION ET ÉCOLOGIE Ivodea mayottensis Labat & M.Pignal, sp. nov. a été récoltée pour la première fois en 1999, en forêt sèche au sud de Mayotte et en forêt humide basse dans l’extrême nord de l’île sur des sols squelettiques et des pentes assez fortes (Fig. 10). PHÉNOLOGIE Floraison: avril à juillet; fructification: juin à juillet. NOM VERNACULAIRE Mvori voua [en Shibushi, informateur Maolida M’Changama] (Barthelat & Viscardi 1813, 1822, 1823, 1826, 1827, 1830 & 1831). NOTES Ivodea mayottensis Labat & M.Pignal, sp. nov. est morphologiquement proche d’ I. choungiensis, mais en diffère par de nombreux caractères, dont les plus importants sont la présence d’une pubescence sur les organes reproducteurs d’ I. mayottensis Labat & M.Pignal, sp. nov., depuis les axes de l’inflorescence jusqu’à l’ensemble des pièces florales et des fruits, alors que ces structures sont glabres chez I. choungiensis. Par ailleurs, les feuilles d’ I. mayottensis Labat & M.Pignal, sp. nov. sont plus grandes et moins coriaces que celle d’ I. choungiensis. STATUT DE CONSERVATION Ivodea mayottensis Labat & M.Pignal, sp. nov. n’est connue que de deux localités et avec une zone d’occupation de 20 km ², l’espèce est provisoirement classée « En Danger » (EN B 2ab(i,ii,iii)) conformément aux critères pour la Liste Rouge de l’UICN (2012). La population d’ I. mayottensis Labat & M.Pignal, sp. nov. est dispersée dans son habitat fortement fragmenté qui ne cesse de décliner par sa surface et sa qualité, plus particulièrement en ce qui concerne la forêt sèche.Published as part of Rabarimanarivo, Marina N., Rakotonirina, Nivo H., Phillipson, Peter B., Lowry Ii, Porter P., Labat, Jean-Noël & Pignal, Marc, 2015, Révision du genre Ivodea Capuron (Rutaceae), endémique de Madagascar et de l'archipel des Comores, pp. 63-102 in Adansonia 37 (1) on pages 89-90, DOI: 10.5252/a2015n1a6, http://zenodo.org/record/768594
Barthélémy D., Barthez A., Labat P. — Patrimoine foncier et exploitation agricole.
No full textBarthélémy D., Barthez A., Labat P. — Patrimoine foncier et exploitation agricole. . In: Économie rurale. N°165, 1985. pp. 56-57
Reply to comment of Legates et al.
No full textIn the previous comment, Legates et al. express concern about the statistical reliability of the positive runoff–temperature relationship presented by Labat et al. We are grateful for this opportunity to respond to these concerns. As Legates et al. correctly points out, the effect of temperature on runoff is a complex relationship, which involves precipitation, evaporation, anthropomorphic affects, among others. As such, the effect of increased temperature on runoff is strongly dependent on the identity of the watershed of interest. For example, a watershed located in a glaciated region, such as Iceland, exhibits a strong positive correlation between runoff and temperature, whereas a watershed located in a arid climate, such as the Sahara desert, exhibits a negative correlation; often there is no run off at all during the summer months in such watersheds
Marsdenia mayottae W. D. Stevens, Labat & Barthelat 2016, spec. nova
No full textMarsdenia mayottae W.D. Stevens, Labat & Barthelat, spec. nova (Fig. 1, 2). Typus: M AYOTTE: Grande Terre, Bandré, Rassi Abambo, 9.II.2001, Barthelat, M’Changama & Ali Sifari 295 (holo: P [P00229277]!; iso: G!, K!, MAO!, MO!, P [P00282507]!). Marsdenia mayottae W.D. Stevens, Labat & Barthelat is most similar to M. vohiborensis Choux, but differs from this species by its umbonate style apex completely covered by the terminal anther appendages and the absence or near absence of a corona. Shrub or twining vine, woody but apparently not corky, underground parts unknown, stems densely appressedpuberulent, sparsely lenticellate, internodes 1-6 cm; latex white. Leaves opposite; blades 6.5-11.1 × 4-9.2 cm, ovate to elliptic, glabrous or puberulent on veins below; apex acuminate to attenuate; base truncate to shallowly lobate, its sinus up to 5 mm deep, lateral veins 4 to 6, colleters 10 to 24; petiole 2.4-5.5 cm, sparsely puberulent. Inflorescences solitary, paniculate with 2 to 6 congested-racemose, appressedpuberulent branches; peduncle (3) 10-48 mm; fertile axes up to 3 cm long, more or less covered with pedicel scars. Flowers borne on pedicels 4–9 mm long; bracts numerous and conspicuous, 1.5-10 × 0.6-4 mm, elliptic to spathulate, sometimes leaf-like; calyx with 1 colleter below each sinus within, lobes elliptic to ovate with round tips, unequal, 3-4 × 1.7-2 mm, sparsely puberulent along axis abaxially, not ciliolate, green; corolla shallowly campanulate, dull yellow, without calli, barbate in distal half of tube and proximal half or more of each lobe adaxially, glabrous abaxially, tube 1.7-2.3 mm, lobes elliptic with tip rounded, 2.2-3 × 1.6- 1.7 mm, patent; corona lobes absent or if present reduced to a fleshy tooth adnate to base of anther, deltate, up to 0.4 mm long, 0.2 mm wide at base; gynostegium nearly sessile, guide rails 0.7 mm long, slightly salient at base; anthers trapezoidal, nearly rectangular, 0.8-1 × 0.8-1 mm, terminal appendages 0.6 × 0.6 mm, elliptic to ovate, translucent, corpusculum ellipsoid to subsagittoid, 0.19-0.28 × 0.08-0.13 mm, translators flat, 0.19-0.25 × ca. 0.05 mm, pollinia ellipsoid to obovoid, 0.39-0.43 × 0.24-0.3 mm; style apex umbonate, 1.4-1.5 mm wide at base. Follicles narrowly ovoid with asymmetrical base, 7.5-9.5 × 2.5-3.5 cm, smooth, glabrous, follicle wall 5-7 mm thick; seeds elliptic, 8-11 × 5-7 mm, dark grey-brown with red-brown mottling, margin 0.6-0.7 mm wide, distally entire or inconspicuously crenulate, surface smooth, coma 3.5-4 cm long, white. Distribution, habitat and phenology. – Marsdenia mayottae is only known from Mayotte, where it can be found at low elevations (less than 10 m a.s.l.) in littoral forest growing with Thespesia populnea (L.) Sol. ex Corrêa, Xylocarpus granatum Koenig, Mimusops comorensis Engl., Maytenus undata (Thunb.) Blakelock and Calophyllum inophyllum L. It is also found on coastal squeletic soils on basaltic rock or in dry littoral scrubland with Grewia picta Baill., G. triflora (Bojer) Walp., Guettarda speciosa L. and Maytenus undata. In addition, it can be found also on calcareous sand soil with Talipariti tiliaceum (L.) Fryxell. The new species is very rarely present also in dry lowland forest on other substrates at up to 100 m. Marsdenia mayottae has been recorded in flower from November to January and in fruit in May and June. Vernacular names and local use. – The following vernacular names in Shibushi have been recorded for M. mayottae by Barthelat & Boullet (2005) or on herbarium labels: “Pamba suisui be” or “Pamba suisui famakitrano”, “Macarangana vahi”, “Vahy rotono”, “Vahy maro” and “Kidoro voalavo”. The plants are used in the preparation of magic potions known as “grigris” (M. M’changama, pers. comm.). Conservation status. – Marsdenia mayottae is only known from highly threatened littoral and lowland dry forests on Mayotte, and its population, as currently known, is highly fragmented. It is only known from five locations despite intensive inventories in the last decades. Thus, its preliminary risk of extinction can be assessed as “Endangered” [EN B2ab(iii)] following the IUCN Red List Categories and Criteria (IUCN, 2012). Notes. – This species shares a dense, bracteate inflorescence with M. vohiborensis Choux from the central plateau of Madagascar. However, M. vohiborensis has a long-exserted style apex while M. mayottae has an umbonate style apex completely covered by the terminal anther appendages. The absence or near absence of a corona in M. mayottae is unique among the species of Marsdenia of Madagascar and the Comoros, and rare in the genus. Paratypi. – M AYOTTE: Grande Terre, Saziley, 17.I.2001, Barthelat & Ali Sifari 233 (G, K, MAO, MO, P); Petite Terre, Labattoir, Plage de Moya, 15.I.2002, Barthelat & Ali Sifari 694 (K, MAO, MO, P); ibid. loc., 15.I.2002, Barthelat & Ali Sifari 699 (MAO, MO, P); Grande Terre, Mliha, Mtsumbatsu, 20.XII.2001, Barthelat et al. 625 (MAO, MO, P); sommet du Bouzi, X.1850, Boivin s.n. (P); Rassi Maoussi, 17.V.1999, Mas 176 (P); Sohoa, 28.VI.1997, Pascal 942 (G, MO, P).Published as part of Stevens, W. Douglas, Labat, Jean-Noël & Barthelat, Fabien, 2016, Two new species of Apocynaceae, Asclepiadoideae from Mayotte, pp. 127-134 in Candollea 71 (1) on pages 128-131, DOI: 10.15553/c2016v711a15, http://zenodo.org/record/572143
Oscillations in land surface hydrological cycle
No full textHydrological cycle is the perpetual movement of water throughout the various component of the global Earth's system. Focusing on the land surface component of this cycle, the determination of the succession of dry and humid periods is of high importance with respect to water resources management but also with respect to global geochemical cycles. This knowledge requires a specified estimation of recent fluctuations of the land surface cycle at continental and global scales. Our approach leans towards a new estimation of freshwater discharge to oceans from 1875 to 1994 as recently proposed by Labat et al. [Labat, D., Godderis, Y., Probst, JL, Guyot, JL, 2004. Evidence for global runoff increase related to climate warming. Advances in Water Resources, 631-642]. Wavelet analyses of the annual freshwater discharge time series reveal an intermittent multiannual variability (4- to 8-y, 14- to 16-y and 20- to 25-y fluctuations) and a persistent multidecadal 30- to 40-y variability. Continent by continent, reasonable relationships between land-water cycle oscillations and climate forcing (such as ENSO, NAO or sea surface temperature) are proposed even though if such relationships or correlations remain very complex. The high intermittency of interannual oscillations and the existence of persistent multidecadal fluctuations make prediction difficult for medium-term variability of droughts and high-flows, but lead to a more optimistic diagnostic for long-term fluctuations prediction. (c) 2005 Elsevier B.V. All rights reserved
FIG.1 in Une nouvelle espèce de Foetidia (Lecythidaceae, sous-famille Foetidioideae) en danger critique d'extinction récemment découverte à Mayotte, archipel des Comores
No full textFIG.1. — Foetidia comorensis Labat, Bidault & Viscardi, sp. nov.: A, rameau fleuri; B, fruit mature; C, sépale pétaloïde du fruit mature; D, détail du style et des bractéoles du réceptacle du fruit mature. Échelles: A, B, 1 cm; C, D, 0,5 cm. A, Viscardi & Guiot 219; B-D, Viscardi et al. 101. Dessin Marion Madeira.Published as part of Labat, Jean-Noël, Bidault, Ehoarn & Viscardi, Guillaume, 2011, Une nouvelle espèce de Foetidia (Lecythidaceae, sous-famille Foetidioideae) en danger critique d'extinction récemment découverte à Mayotte, archipel des Comores, pp. 263-269 in Adansonia (3) 33 (2) on page 265, DOI: 10.5252/a2011n2a11, http://zenodo.org/record/519775
Tylophora mayottae W. D. Stevens, Labat & Barthelat A. Habit 2016, spec. nova
No full textTylophora mayottae W.D. Stevens, Labat & Barthelat, spec. nova (Fig. 3, 4). Typus: M AYOTTE: Grande Terre, Mamoudzou, réserve forestière de Majimbini, La Convalescence, 5.IX.2001, Barthelat et al. 483 (holo-: P [P00229464]! iso-: BR!, K!, MAO!, MO!). Tylophora mayottae W.D. Stevens, Labat & Barthelat is similar to T. coriacea Marais, but with smaller flowers which are rotate and a shorter corolla tube (0.2-0.5 mm) and with guide rails which are shorter (0.15-0.2 mm). Twining and trailing vine with white latex. Stems rooting at nodes, woody and corky below, with hirsutulous indument present at the nodes and sometimes extending in a continuous line along the internodes; internodes 3-14 cm long. Leaves opposite; blades 6.7-13.5 × 4-8.8 cm, ovate to elliptic, apex acute to acuminate, base obtuse to truncate or shallowly lobed with a sinus up to 7 mm deep, both surfaces glabrous, glossy, succulent, margin thickened, lateral veins 4 to 6, colleters 2 to 10, sometimes raised on a fleshy pad; petioles 0.7-3.4 cm, glabrous or hirsutulous on the upper side. Inflorescence 4.5- 6.0 cm long, with hispidulous indument forming a continuous line on the axis; peduncle 1.7-2.2 cm when in flower, up to 5.3 cm long when in fruit. Flowers borne on pedicels 0.5- 0.6 cm long; bracts 2.2 × 0.3 mm, linear to lanceolate; calyx apparently without colleters, lobes 1.3-1.3 × 0.5 mm, lanceolate, apex acute, glabrous or with a few hairs on midrib and margin; corolla pale pink, glabrous outside, densely white-hispid inside with hairs 0.15 mm long, tube 0.2–0.5 mm, lobes 2-2.5 × 1-1.2 mm, lanceolate with acute apex; corona pale yellow 1.0 mm high, 1.5-1.6 mm in diam., 5-lobed; lobes free, erect, more or less reaching to the base of anthers, apices rounded; c o r p u s c u l u m n a r ro w l y e l l i p s o i d, 0.2 -0.2 2 × 0.0 7 - 0.08 mm, translators 0.09 mm long, pollinia ellipsoid, 0.18-0.2 × 0.14-0.16 mm; ovaries glabrous. Follicles 8.2 × 1.1 cm, narrowly fusiform, glabrous, smooth, green; seeds 10-11 × 5.5-6.5 mm, dark brown, margin 0.8 mm wide, irregularly toothed on distal third, surface smooth, finely hispidulose on both sides; coma 2-2.5 cm long, white. Distribution, habitat and phenology. – Tylophora mayottae is only known from Mayotte, it has been recorded in sub-humid to humid forest between 200 to 400 m in the Majimbini and Combani forest reserves on Grande Terre and in the coastal forests at Saziley on Grande Terre and at Moya on Petite Terre. It has been recorded in flower in October and November, and in mature fruit in September, but flowering and fruiting probably spans at least from August to December. Vernacular names and local use. – The new species is known from data recorded by Barthelat & Boullet (2005) or on herbarium labels as “Vahy rountou”, “Vahy rotono be” or “Pamba suisui be” in Shibushi dialect, and “Ouvamba suisui bole” in Shimaore dialect. The plant is used in the preparation of magic potions known as “grigris” (M. M’changama pers. comm.). Conservation status. – Tylophora mayottae is rare and clearly has a restricted distribution. It is known from only three recent collections from three separate protected areas, and three collections from the XIXth century, two of which have no locality details other than “ Mayotte ”. The preliminary risk of extinction of Tylophora mayottae is therefore assessed as “ Vulnerable” [VU D2] following the IUCN Red List Categories and Criteria (IUCN, 2012). Further information on the extant population is needed to be able to provide a more reliable assessment of the conservation status of the new species. Notes. – Tylophora mayottae is vegetatively similar to T. coriacea, which is restricted to Mauritius, Reunion and the Seychelles, but differs from it by its smaller flowers which are rotate (vs. subcampanulate), with a shorter corolla tube (0.2-0.5 vs. 1.7-2 mm) and shorter guide rails (0.15-0.2 vs. 0.6-0.8 mm). In a recent molecular study (Liede-Schumann et al., 2012), Tylophora and a variety of other tropical genera were placed in synonymy with the north-temperate genus Vincetoxicum Wolf. However the authors are not convinced of the merits of this view, and prefer to maintain the genus Tylophora as distinct until more compelling evidence is available. Paratypi. – M AYOTTE: Grande Terre, Bandré, Saziley, La Convalescence, 30.IX.2003, Barthelat et al. 1242 (P); Grande Terre, Bandré, Saziley, La Convalescence, 29.XI.2005, Barthelat et al. 1526 ᵐ); sine loc., Boivin s.n. (P); sine loc., XI.1850, Boivin 3210 (K, P); forêt de Combani, 21.X.1884, Humblot 1336 (K, P).Published as part of Stevens, W. Douglas, Labat, Jean-Noël & Barthelat, Fabien, 2016, Two new species of Apocynaceae, Asclepiadoideae from Mayotte, pp. 127-134 in Candollea 71 (1) on pages 131-132, DOI: 10.15553/c2016v711a15, http://zenodo.org/record/572143
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