Amyema kebarensis Barlow

Distribution Map

Amyema kebarensis Barlow, Austral. J. Bot. 22 (1974) 579. - Type: van Royen & Sleumer 8256 (holo L 963.204-39; iso CANB 131383), New Guinea, Vogelkop. Kebar Valley, opposite Andjai, 700 m. on Vaccinium cavendishoides and Trochocarpa laurina. 19.xii.1961.

For description see Barlow, Austral. J. Bot. 22 (1974) 579. Amyema kebarensis has few specialized characters and thus presents a relatively generalized facies for the genus. It can be distinguished locally by its very slender habit. its small, thin, very narrow acuminate leaves, 3- or 4-rayed umbel of triads, and 4-merous corolla. The flower colour is described as red or purple in the lower part and green or yellow above.

Amyema kebarensis is known only from the Vogelkop, Irian Jaya (fig. 9; 5 collections seen), from 700 to 2100 m elevation. Habitat details are poorly known; recorded hosts are Clethra sp., Vaccinium cavendishoides, and Trochocarpa laurina. The species is probably a young local endemic, but its affinities are difficult to assess.

Amyema kebarense Barlow, sp. nov.

Type-West Irian, Kebar Valley, above Sulphur Springs opposite Andjai, 700 m alt., van Royen and Sleumer 8256, 19.xii.1961 (L 96320439; CANB 131383).

Frutex parvus, ramisissimus, stolonibus numerosis gracilibus. Inflorescentia calyx corollaque pilis paucis dissitis vestitis; ceterum glaber. Rami graciles, lenticellis elongatis pustulati. Folia opposita; lamina anguste lanceolata, 4-7 cm longa, 0.4 - 0.7-(l.3) cm lata, apice acuminata acuta, paginis obscuris, revoluta ubi sicca, basi in petiolum 1-3 mm longum sensim attenuata. Inflorescentiae 1-3 in axillis ortae, pedunculatae, umbellatae; umbellae 3- (vel 4-) radiatae; radiis apice trifloris, fore mediano sessili lateralibus pedicellatis; pedunculus gracilis, (8)-l0-l5-(20) mm longus; radii c. 8 mm longi; pedicelli in statu florendi 2-3 mm longi, in statu fructi-fero longiores; bracteae parvae, obtusae, patulae, 1 mm longae. Calyx angustus, leviter infundibuliformis, 2 mm longus; limbus c. 0.3 mm longus. Corolla in alabastro maturo gracilissima, apice rotundata pilis paucis dissitis albis, 4-mera, c. 18 mm longa. Antherae acutae, 2 mm longae; pars liberae filamentae 4 mm longae. Fructus prope globularis, 6 mm longus.
Small much-branched shrub with many slender runners, glabrous except for a few scattered hairs on the inflorescence, calyx and corolla. Stems terete, slender, pustulate with elongate lenticels. Leaves opposite; petiole 1-3 mm long; lamina narrow lanceolate, rolled when dry, 4-7 by 0.4-0.7 (l.3) cm, dull on both sides, gradually attenuate at the base, acuminate and acute at the apex; venation invisible. Infiorescences 1-3 in the axils; peduncle slender, (8)-l0-l5-(20) mm long; rays 3 (or 4), slender, wider towards the apex, often curved, c. 8 mm long; pedicels of the lateral flowers of the triads 2-3 mm long in flower but longer in fruit; bracts small, spreading, obtuse, 1 mm long. Calyx narrow, slightly funnel-shaped, 2 mm long; limb only c. 0.3 mm long. Corolla in the mature bud very slender, with a few scattered white hairs at the tip, rounded at the apex, c. 18 mm long, 4-merous. Anthers acute, 2 mm long; free parts of the filaments 4 mm long. Fruit nearly globular, 6 mm long.

Occurrence. Kebar Valley, Vogelkop Peninsula, West Irian (Fig. 6), 700 to 2100 m altitude. The only recorded host is Clethra sp.

Specimens Examined. WEST IRIAN: Kebar Valley, Nertoi (opposite Andjai) to Mt. Tobi, 700 m alt., van Royen and Sleumer 6845, 11 .x. 1961 (L); Kebar Valley, Watjetoni Mt., 1200 m alt., Versteegh BW 10330, 23.xi.1960 (L); Arfak Mts., Anggi Gita Lake to Mt. Koebre, 2100 m alt., Sleumer and Vink 4297, 16.i.1962 (L; LAE).

While Amyema kebarense has no unique diagnostic characters, it is distinguished from most of its congeners by its slender habit, small narrow leaves and 4-merous flowers. It is a well-defined and sharply distinct species, but its lack of specialized characters makes its affinities difficult to assess.

Illustrations

Amyema kebarensis

updated 18 January 2007