Adenia barthelatii M. Pignal, Yockteng, Hearn & Labat, 2013

PIGNAL, MARC, YOCKTENG, ROXANA, HEARN, DAVID J. & LABAT, JEAN-NOËL, 2013, Adenia barthelatii (Passifloraceae), a new endemic species of Mayotte and its phylogenetic status within the genus Adenia, Phytotaxa 99 (1), pp. 40-48 : 42-44

Adenia barthelatii M. Pignal, Yockteng, Hearn & Labat , sp. nov. ( Fig. 1 )

A. boivinii affinis , sed differt laminae foliorum aliquanda trilobata; laminae integrae et lobus medianus foliorum trilobatorum longe trinervata.

Type :— MAYOTTE. Sohoa Forest Reserve [12°48’S, 45°6’E], 4 September 2001, Barthelat, M. Pignal, M. M'Changama & A.B. Sifary 479, fl ♀, fr, (holotype P! P00229460, isotypes P! P00256463 (wood collection), P00354135 (spirit collection); P00354136 (spirit collection), MAO!) .

Plant a liana. Trunk white-grayish, bulged and succulent, up to 1–1.5m, 30–40 cm in diameter, terminating in a green stem covered by a white powered wax. Wood soft and spongy of low density. Young branches with lenticels. Plant monoecious, male and female flowers with apparently distinct flowering times within a plant, inferred from a male-flowering individual possessing fruits. Leaves of two main shapes: elliptic-cordate or 3- lobed; petiole 4–8 cm long; lamina peltate at base by 1mm, glabrous, occasionally asymmetrically divided into two lobes (rather than elliptic-cordate or 3-lobed). In elliptic-cordate lamina, venation brochidodromous, primary and secondary venation deep, secondary veins 3, perpendicular to primary venation, basal veins ending two thirds up from leaf base, higher order veins conspicuous; in 3-lobed lamina, middle lobe lanceolate, 8 x 2–3 cm, base narrow, lateral lobes lanceolate, asymmetric, 6 x 1.5–2 cm, two veins. Stipules minute, ca. 1–2 mm, black. Glands on lamina 1–5, usually paired on opposite sides of, and 5–10 mm from, mid-vein, gland at base of lamina single, on peltate extension. Tendrils 10–15 cm long. Female inflorescences in old wood at the base of main branches or in branches with leaves. Bracts, thick, brown, 0.5 x 0.2 mm. Flowers deep green to yellow cream. ♁ and ♀ inflorescences in short racemes of ca. 8 flowers. ♁ and ♀ flowers tubular. ♁ Flower: pedicel 5 x 0.5 mm. Stipe indistinct, 2 x 0.8 mm. Hypanthium tubular, 13 x 1.3 mm, flaring apically to 2 mm. Sepals 5, curved, linear, 3 central veins conspicuous on the internal side, prolonged into the margins by longitudinal veins and by anastomosed veins at the apex. Three sepals internal and two external due to imbrication; external sepals linear, 8 x 4 mm, lateral margins and apex with filamentous tip; internal sepals linear, 10 x 4 mm, apex round and thin with irregular, fine dentition. Petals 5, alternating with and shorter than sepals, elliptical lanceolate, 9 x 2 mm, apices curved with three conspicuous veins on the internal side of each. Corona very reduced. Nectaries not visible. Stamens 5, alternating with the petals, filaments flattened, 30 mm long, flat, adnate to the hypanthium. Septa linear along the tube forming the hypanthium, appearing from connation of staminal filaments, anthers basifixed, 11 x 1 mm, bases rounded. Aborted gynoecium deeply inserted in the receptacle with ovary; ovary pale orange, 0.2 x 0.3 mm, stylodes, 1.2 x 0.2 mm. ♀ Flower: pedicel ca. 3 x 1 mm, base enlarged. Stipe indistinct, 3 x 0.6 mm. Hypanthium, 5 x 3 mm, tubular, flaring apically to 2 mm. Sepals 5, curved, linear, veins conspicuous on the internal side, prolonged into the margins by longitudinal veins and by anastomosed veins at the apex. Three sepals internal and two external due to imbrication; external sepals linear, 10 x 4 mm, lateral margins curved; internal lobes linear, 12 x 4 mm, veins 7, reticulated, margins rounded and thinned with irregular, fine dentition. Petals 5, alternating with sepals, shorter than sepals, elliptical-lanceolate, 4 x 2 mm, 3 conspicuous veins on the internal side. Corona reduced to scales alternating the petal lobes, ca. 1 mm. Nectaries not visible. Staminodes 5, base of flattened filaments fused forming a 3 mm collar at the base of the ovary, anthers rudimentary, 0.5 x ca. 0.1 mm Gynoecium green, ovary fusiform, ca. 1cm, stipitate (stipe ca. 5 mm), style 5 mm, divided in 3 branches of ca. 1 mm, stigmas 3, white-beige, cottony and stipitate. Capsules ellipsoid, angular, 7 x 3.5 cm; carpels 3, green yellowish at maturity, fruit stipe curved, ca. 1 cm. Seeds compressed, sub-orbicular, 4 x 7 mm, light brown, covered with small depressions (ca. 50 per seed side), surrounded by a transparent aril. Each fruit produces ca. 60 seeds.

Vernacular names: —Vahy Hazu (Shibushi / buc ISO639-3) meaning “Tree liana”, Mouri Tandry (Shimaore / swb ISO 639-3).

Ecology and distribution.— Adenia barthelatii is present in two localities of Mayotte as relict populations. Locally, it can be very abundant, particularly in the Sohoa forest where it colonizes scree slopes. Sohoa is considered the last low altitude humid forest in the island. This new species might be present on other islands of the Comoros Archipelago but was not observed during the recent expeditions in 2009-2011.

Etymology:—This taxon is dedicated to Fabien Barthelat (Service Environnement et Forêt de Mayotte), who is a member of our project. Fabien enthusiastically explored all natural habitats of Mayotte, collecting essential material to characterize the flora of Mayotte.

Paratypes: — MAYOTTE. Sohoa Forest Reserve , rain forest, 5 July 2001, fl ♀, fr, F. Barthelat, M. M'Changama, A.B. Sifary, F. Jacq, Saïd Assani & Madi Maolida. 433 ( MAO!, P!: P00229414) ; MAYOTTE. Majimbini , Majimbini Forest Reserve, Convalescence, rain forest, 10 June 2002, fl, F. Barthelat et F. Jacq 932 (P!: P00749172) ; MAYOTTE. Majimbini , Majimbini Forest Reserve, Convalescence, rain forest, 26 June 2002, fl, F. Barthelat M. M'changama & B. Ali Sifari 948 (P!: P00749174) ; MAYOTTE. Majimbini , Majimbini Forest Reserve, Convalescence, rain forest, 16 November 2002, st, F. Barthelat & R. Rolland 1081 (K!, MAO!, MO!, P!: P00339154, P00339198) ; MAYOTTE. Convalescence , RF Majimbini , rain forest, 1 July 2003, fl ♂, F. Barthelat, M. M'changama, A. Andhumou & B. Ali Sifari 1205 ( MAO!, P!: P00437877) ; MAYOTTE. Convalescence, Majimbini RF, rain forest, 1 July 2003, fr, F. Barthelat, M. M'changama, A. Andhumou & B. Ali Sifari 1206 ( MAO!, P!: P00437878) ; MAYOTTE. Chiconi , Sohoa, Sohoa Forest Reserve, dense humid (rain) forest, stony scree, 12°48’27"S, 45°6’22"E, 90 m, 24 November 2000, fr, J.-N. Labat, F. Barthelat, M. Mchangama & A.B. Sifary 3291,(K!, MAO!, MO!, P!: P00209745) ; MAYOTTE. Sohoa , 12 July 1999, fr, Mas 308 ( MAO!, P!: P00176534) ; MAYOTTE. Sohoa , 120 m, 12 December 1996, st, O. Pascal & J.- N. Labat 828 (K!, MAO!, P!: P00144789) .

Phenology:— Flowers observed in July and September, fruits in July and November.

Note:— Pictures of living plants can be retrieved using image numbers http://coldb.mnhn.fr/ CatalogNumber/MNHN/P/P00229414, P00437877, P00437878, P00339154, P00339198 and P00354135.

Conservation status:— according to Using IUCN criteria ( IUCN 2010) Adenia barthelatii is assessed as Vulnerable (VU) based on criteria D2 (Restricted area of occupancy and number of locations with plausible future threat that could drive the taxon to EX (extinct) or CR (critically endangered), number of locations ≤5) for which there is a plausible threat to their loss. Adenia barthelatii is known from only two localities, the Sohoa and Convalescence forest.

Figures

FIGURE 1. Adenia barthelatii. A. Habit, scale bar 30 cm; B, C. Stem and leaves, scale bar 2 cm; D, E. ♁ flower, scale bar 4 mm; F, G.♀ flower, scale bar 4 mm; H. ♀ inflorescence and fruit, scale bar 1 cm; I. open fruit, scale bar 1 cm;. A–C, I, from Labat et al. 3291, D, E, from Barthelat et al. 1205, F, G, H from Barthelat et al. 433. Drawing by Agathe Haevermans.