Abrahamia betamponensis Randrian. & Lowry, 2017

Randrianasolo, Armand, Lowry II, Porter P. & Schatz, George E., 2017, Taxonomic treatment of Abrahamia Randrian. & Lowry, a new genus of Anacardiaceae from Madagascar, Boissiera 71, pp. 1-152 : 34-35

2. Abrahamia betamponensis Randrian. & Lowry , spec. nova ( Fig. 2 ).

Typus: MADAGASCAR. Prov. Toamasina: Rég. Atsinanana , Betampona RN, [17°55’S 49°13’E], 24.X.1955, bud, Réserves Naturelles 7701 (holo-: P [ P06774885 ]!; iso-: TEF [ TEF000880 ]!) .

Diagnosis

Abrahamia betamponensis Randrian. & Lowry can easily be distinguished from other members of the genus by its large leaves (9-24 3 4.3-8.5 cm) with a remarkably prominent midvein on the abaxial surface, a long, thick petiole (15-18 mm in length), numerous secondary veins (50-60 pairs), and fruit surface covered with dense, short indument.

Description

Trees c. 7 m tall; bark with lenticels; young twigs whitish-gray to light tan, pubescent at the very tips. Leaves opposite or subopposite; blade oblanceolate, 9-24 3 4.3-8.5 cm, subcoriaceous to coriaceous, apex shortly acuminate, retuse or emarginate, margin slightly revolute, base cuneate, adaxial surface glabrous, abaxial surface sparsely strigose along midvein, venation craspedodromous, midvein strikingly prominent abaxially, secondary veins 50-60 pairs, 2-5 mm apart, raised on both surfaces, tertiary veins visible on both surfaces, petiole 15-18 mm long, canaliculate on adaxial surface, c. 2.5-3 mm in diam., glabrous. Inflorescence terminal and axillary, a panicle, 2-7 cm long, axes thick, covered with dense, short, appressed indument; bracts triangular, c. 4 3 2 mm, adaxial surface glabrous, abaxially surface with short, appressed indument. Male flowers 5-merous, small, c. 3 mm long, subtended by a small, deltoid bract; pedicel short, c. 1 mm long, strigose; calyx lobes triangular, 2.5 3 1 mm, adaxial surface glabrous, abaxial surface pubescent; corolla lobes very widely ovate, 2 3 2 mm, adaxial surface glabrous, abaxial surface pubescent; stamens 5, filaments 1.2-1.3 mm long, anthers c. 1 mm long, ovoid; disk thin, dish-shaped and glabrous. Female flowers unknown. Fruits 2.4-3.2 3 1.4-1.8 cm, ellipsoid, covered with dense, short indument, with longitudinal striations.

Vernacular names

“Hazombarorana”, “Hazombarorana à grandes feuilles”, “Vatodinga’’, “Voatodinga”.

Distribution, ecology and phenology

Abrahamia betamponensis is known only from Betampona reserve and its vicinity, with a single collection from Zahamena national park ( Map 1 ). It occurs in mid-elevation humid forest. Material in bud has been collected in October and fruiting specimens have been made in January.

Conservation status

Abrahamia betamponensis has a minimum EOO of 8 km 2, but its two known localities are both situated within protected areas (Betampona reserve and Zahamena national park) so in the absence of any data on population size, no future decline is expected in terms of AOO, EOO, or quality of habitat. It has therefore assigned a preliminary status of “Least Concern’’ [LC] using the IUCN Red List Categories and Criteria ( IUCN, 2012).

Notes

Abrahamia betamponensis belongs to a group of species with large leaves (up to 37 cm long) that have numerous (40-70) secondary veins. Within this group, A. betamponensis most closely resembles A. sambiranensis , but differs by the dense, short indument on the surface of its mature fruit (vs glabrescent or glabrous).

Paratypi

MADAGASCAR. Prov. Toamasina: Rég. Antisnana, Fotsimavo , [Betampona RN], [17°55’S 49°13’E], 300-400 m, 20.I.1950, fr., Réserves Naturelles 2366 ( P, TAN); ibid. loco, Réserves Naturelles 2489 ( P, TAN); Anjiro, Ambodiriana, [Betampona RN], [17°55’S 49°13’E] , 26.X.1957, bud, Réserves Naturelles 9148 ( P, TEF); Mangabe , [Zahamena PN], [17°42’S 48°54’E], 20.I.1963, old fr., Réserves Naturelles 12446 ( MO, P, TEF); Betampona RN, 17°54’29”S 49°12’16”E, 530 m, 13.I.2017, ster., Schatz et al. 4472 ( MO, P, TAN) .

Figures

Map 1. Geographic distribution of species of Abrahamia Randrian.& Lowry

Fig. 2. Abrahamia betamponensis Randrian. & Lowry. A. Fruiting branch; B. Fruit showing indument.