Vatica abdulrahmaniana Chua, 2015

Chua, Lillian Swee-Lian, Nor-Ezzawanis, A. T., Yong, W. S. Y. & Hamidah, M., 2015, Two new species of Vatica (Dipterocarpaceae) from Peninsular Malaysia, Phytotaxa 222 (3), pp. 229-237 : 233-235

Vatica abdulrahmaniana Chua , sp. nov. ( Fig. 5 , 6 , 7 ).

Type:— MALAYSIA. Perak: Keledang Sayung Forest Reserve, Bukit Keledang , 720 m elev., 40035.37 ’ N, 101000.38 ’ E, 27 July 2010 (fr.), Y. C. Chan FRI 65809 (holotype KEP!; isotypes SAN!, SAR!, K!, L!) .

Vatica abdulrahmaniana differs from other species in having prominent leaf scars and persistent axillary buds on its older twigs. Its young leaves are pubescent with golden brown stellate hairs on lamina and veins, becoming glabrescent in older leaves. When fresh, the lower surface is slightly glaucous. Its floral bracts are elliptic-lanceolate, leafy green when fresh, veined, pubescent and measures 10 × 4 mm. In particular, it differs from V. nitens King (1893: 104) in having very few to no intermediate veins between lateral veins and persistent golden-brown tomentum in flowering and fruiting twigs.

Tree to 20 m tall, clear bole to ca. 15 m, 30 cm dbh, no buttress. Bark with appressed, non-peeling scales, some parts smooth, inner bark and sapwood creamy-yellow with no dammar exudation. Crown small, rather lax, not spreading. Young twigs to 6 mm diameter, terete, ribbed, all parts densely covered with golden-brown globose stellate hairs, older twigs stout to 8 mm diameter, glabrous with prominent leaf scars and persistent dried buds. Buds with similar appressed hairs, stipules caducous. Leaves elliptic-lanceolate, 14 − 22 × 4 − 9 cm, thickly coriaceous, base obtuse to rounded, veins 13 − 18 pairs, raised above, prominent beneath, arching to form intramarginal vein close to margin, few to no intermediate veins, tertiary veins scalariform-reticulate, prominent beneath, raised above, lamina and veins on both surfaces densely pubescent golden-brown stellate hairs, older leaves glabrescent, lower surface when fresh slightly glaucous. Petiole 25 − 35 mm long, stout. Inflorescence panicle to 18 cm long, singly or doubly branched, branchlets bearing up to 4 flowers, axillary on young leafy shoots and occasionally on leafless twigs, branching lax, all parts pubescent with a combination of erect and appressed stellate hairs, bracts elliptic-lanceolate, apex acute, leafy green when fresh, veined, pubescent, 10 × 4 mm, peduncle to 7.5 cm. Flowers buds fusiform, 7 × 2 mm, pedicel to 1 mm long, sepals 5, unequal shaped, 2 lanceolate, 3 deltate, 5 × 1 mm, pubescent except for basal area of inner surface, petals 5, imbricate-contorted, elliptic-ovate, apex acute, to 7× 2 mm, outer surface pubescent, inner surface glabrous, stamens 14 − 17 in 2 whorls, single, filament very short, broadly triangular, tapering more less to anther, anthers elliptic, 0.75 × 0.25 mm, stigma capitate, 4-sided, style columnar, 1 mm, tapering to ovary, ovary inferior. Fruit pubescent in all parts, pedicel to 5 mm long, calyx lobes unequal, free to base, 2 longer lobes obovate, acute, to 7.0 × 2.5 cm, ca. 4 mm broad at base, 3 shorter lobes elliptic, acute, to 2.3 × 0.7 cm, nut superior, to 9 mm, subglobose.

Etymology:—The species is named after the current Director-General of the Forest Department of Peninsular Malaysia, Dr. Hj. Abdul Rahman bin Hj. Abdul Rahim.

Distribution and habitat:—It is endemic to Peninsular Malaysia, known only from Bukit Keledang in Keledang Sayung Forest Reserve. It occurs on steep hill slopes greater than 300 at the forest margin along the road to the Telecommunication station at 720 m elevation.

Ecology and phenology:—The forest lies in the ecotone of hill and upper hill dipterocarp forests and comprise members of the family Fagaceae and the genus Shorea ( Dipterocarpaceae ) such as S. curtisii Dyer ex King (1893: 111) at lower elevations and S. ovata Dyer ex Brandis (1895: 91) at higher elevations.At least 31 trees of V. abdulrahmaniana have been recorded in the area. In May 2014 (see FRI 47730) two trees bore advance stages of floral buds with more than 75% of its crown in flower. There were no open flowers or young fruits on the trees.

Conservation status:—Rare ( Chua 2012). To date, the species is known only from the type locality. The forest area is used by communities as a recreation area and there is a telecommunication tower at the summit. Accidental destruction by erosion or fire are therefore serious threats to this population.

Additional specimens examined:— MALAYSIA. Perak: Keledang Sayung Forest Reserve, Bukit Keledang , 680 m elev., 4035 ’ N, 101003 ’ E, 21 May 2014, Chua FRI 47730 ( KEP) ; Keledang Sayung Forest Reserve , 720 m elev., 4035 ’ N, 101000 ’ E, 3 November 2009, Yong FRI 65761 ( KEP) .

Figures

FIGURE 5. Vatica abdulrahmaniana. A. Fruiting leafy twig. B. Inflorescence. C. Flower bud. D. Bract. E. Sepals (lanceolate and deltate type). F. Petal, abaxial (left), adaxial (right). G. Gynoecium. H. Longitudinal section of flower bud. I. Arrangement of anthers in flower bud. J. Stellate hairs. A & J based on Y. C. Chan FRI 65809, type collection; B,C,D,E,F,G,H and I based on L.S.L. Chua FRI 47730. Drawing by Mohd.Aidil Nordin.

FIGURE 6. Vatica abdulrahmaniana. A. Crown in flower. B. Inner bark. C. Habit. D. Inflorescence (based on L.S.L. Chua FRI 47730, photographs by Lillian Swee-Lian Chua).

FIGURE 7. Geographic distribution map of Vatica abdulrahmaniana.