Ehretia australis J.S. Mill., 2002

Miller, James S., 2002, A revision of Ehretia (Boraginaceae) for Madagascar and the Comoro Islands, Adansonia (3) 24 (2), pp. 137-157 : 143

1. Ehretia australis J.S. Mill. , sp. nov.

Frutex, ramunculis glabris, ceraceis. Folia decidua, nonnulla alterna sed proparte majore in fasciculos ramunculis lateralibus brevibus insidentes disposita; lamina obovata usque late-obovata, 0.5-1.2(-2.5) cm longa, 0.3-0.9(-2) cm lata, apice rotundata, basi cuneata , margine integra, adaxialiter glabra leviter granulata vel minute strigillosa, abaxialiter glabra vel puberulenta; petiolo 0-3(-5) mm longo. Inflorescentiae terminale, cymosae, 0.7-1.5 cm latae. Flores bisexuales; calyce campanulato, 2.5-3 mm longo, 5-lobo, sparsim puberulo. Fructus late-ovoideus vel globosus, 3.5-4.5 mm longus; pyrenis 4, reticulatis.

TYPUS. — Humbert & Swingle 5517, Madagascar, Prov. Toliara, environs d’Ampanihy , lieux sablonneux, 200-300 m, 24 o 42’S, 44 o 45’E, fl., 30 Aug.-7 Sep. 1928 (holo-, P!; iso-, MO!).

Shrub, the twigs glabrous, waxy. Leaves alternate but mostly borne in fascicles on short, lateral branches, deciduous; blades obovate to widely obovate, the widest point at or above the middle, 0.5-1.2(-2.5) cm long, 0.3-0.9(-2) cm wide, the apex rounded, the base cuneate, the margin entire, the adaxial surface glabrous to slightly granular or minutely strigillose, the abaxial surface glabrous to moderately and evenly puberulent, the venation brochidodromous, all but the midrib evident only on the abaxial surface, the midrib even with or slightly impressed on the adaxial surface, raised on the abaxial surface, the secondary veins 3-4, the tertiary venation reticulate; petioles 0-3(-5) mm long, sparsely puberulent, canaliculate on the adaxial surface. Inflorescences terminal on short lateral spurs, small cymes of c. 10 or fewer flowers, 0.7-1.5 cm broad, peduncle 1-4 mm long, the branches puberulent, the hairs all simple; flowers bisexual; calyx campanulate, 2.5-3 mm long, the 5 lobes 2-2.5 mm long, sharply acute at the apex, sparsely puberulent, ciliate on the margin; corolla pale pink, tubular with reflexed to spreading lobes, the tube 2-3 mm long, the 5 lobes oblong, 2.5-3 mm long; stamens 5, prominently exserted, the filaments 3.5-5 mm long, the upper 2-3 mm free, glabrous, the anthers obloid, 1.2-1.5 mm long; ovary ovoid, c. 1 mm long, the style 2.5-3.5 mm long, divided 1/3-1/2 of its length, glabrous, the 2 stigmas capitate. Fruits drupaceous, borne in the persistent calyx, color at maturity unknown, broadly ovoid to globose, 3.5-4.5 mm long, 3.5-4.5 mm wide, the endocarp bony, separating into 4 pyrenes at maturity, these 3 mm long, 1.5 mm wide, reticulate on the outer surface. — Fig. 2 .

Ehretia australis is distinctive among the Malagasy members of the genus in its small leaves, less than 1.2 cm long and mostly clustered in axiallary fascicles, and small inflorescences, less than 1.5 cm broad.

DISTRIBUTION. — Ehretia australis is known only from dry regions of southern Madagascar (Fig. 3) and the limited collection data available would indicate that it occurs on rocky terrain.

VERNACULAR NAME. — Manindra.

CONSERVATION STATUS. — Provisional IUCN Red List Category: Endangered (EN B1abiiv+B2abi-iv). With an Extent of occurrence of 4,100 sq. km. and an Area of Occupancy of only 500 sq. km. Ehretia australis occurs in an area in southern Madagascar where the vegetation is increasingly fragmented. No populations are known from currently protected areas.

PARATYPES. — MADAGASCAR: Bosser 4082, Prov. Toliara, Ifotaka, 24 o 48’S, 46 o 08’E, fr., Nov. 1952 ( P!) ; Croat 31441, Prov. Toliara, 1-4 km W of Etrobeke, 150 m, 24 o 48’S, 44 o 31’E, fr., 16 Feb. 1975 ( MO!, P!) ; Decary 4303, Prov. Toliara, Antanimora , sur les trachytes, 24°49’S, 45°40’E, fl., 11 July 1926 ( MO!, P!) ; Decary 4466, Prov. Toliara, Antanimora , terrain gneissique, 24 o 49’S, 45 o 40’E, fl., 16 July 1926 ( MO!, P!) ; Dequaire s.n., SW Madagascar, fl., s.date ( P!) ; Randrianasolo 159, Prov. Toliara, 30 km SW of Fort Dauphin, N of the village of Italy, 25 o 09’S, 46 o 45’E, fr., 16 Oct. 1990 ( MO!) ; Services Forestier: SF 12670 (Ralaiarison), Prov. Toliara, Ampanihy , 200 m, 24 o 42’S, 44 o 45’E, fl., fr., 3 Dec. 1954 ( P!) .

Figures

Fig. 2. — Ehretia australis J.S. Mill.: A, flowering branch; B, flower; C, flower with open corolla. A-C, from Humbert & Swingle 5517 (P).