Bull. Acad. Sci. St Petersbourg, ser. 3, 15: 227 (1870).
WFO ID: wfo-0000400494
IPNI ID: urn:lsid:ipni.org:names:331902-1
Verified by:
Shrub to 2.5m tall; bark thin with shallow vertical furrows; young twigs pale
to reddish brown, sparsely to moderately covered with multicellular gland-headed hairs,
becoming glabrous with age; new foliage shoots arising from axillary buds associated
with foliage leaves of the previous year's shoot (i.e. below terminal bud), and some
terminal buds. Vegetative bud scales glabrous to moderately unicellular-pubescent
abaxially, sometimes with a few multicellular gland-headed hairs near apex, sparsely to
moderately unicellular-pubescent adaxially, especially near apex, and sometimes with a
few multicellular gland-headed hairs near apex; margin fringed with unicellular hairs or
with mixed unicellular and gland-headed hairs; lowermost scales with long aristate
apices or rudimentary blades. Leaves deciduous, dark green adaxially, pale green or
occasionally glaucous abaxially, turning yellow to red in autumn, alternate (with
internodes becoming more closely spaced towards tip of shoot), thus leaves sometimes
appearing pseudowhorled at shoot apices. Blade membranaceous, obovate to occasionally
elliptic, 2.1-13.5 x0.9-6.3cm; base attenuate with blade decurrent along petiole; apex
shortly acuminate, acute to obtuse, with a short mucro; midvein strongly raised and
prominent abaxially, the secondary veins slightly raised abaxially; adaxial surface,
including midvein, moderately covered with multicellular gland-headed and eglandular
hairs, the midvein unicellular-pubescent; abaxial surface glabrous to moderately covered
with unicellular hairs, especially near base, and usually with a few multicellular
gland-headed hairs, the lateral (and sometimes all) surfaces of midvein very sparsely to
densely covered with straight to crisped, unicellular hairs, especially towards base,
and with multicellular gland-headed hairs and usually also + flattened glandular to
eglandular hairs, the secondary and tertiary veins similar but less frequently
unicellular-pubescent and usually lacking!flattened glandular hairs; margin serrulate
and often with conspicuous irregular undulations, with a fringe of multicellular
gland-headed and eglandular hairs; petiole ± lacking to 6mm long, sparsely
unicellular-pubescent, especially adaxially, and with scattered multicellular
gland-headed hairs, the base of petiole abruptly expanded into a very broadened point of
attachment, forming a ± triangular'slight protuberance below terete portion. Flower buds larger than, but otherwise similar to, vegetative buds. Flowers appearing before or with the leaves; inflorescence an umbellate raceme of 2 to 5 flowers. Pedicels 5-27mm long, moderately to densely covered with multicellular gland-headed hairs, sometimes also sparsely unicellular-pubescent. Calyx lobes broadly Ungulate to ovate-triangular, 1-3.5 x 1.5-2mm; apex rounded; margin fringed with multicellular gland-headed and sometimes also eglandular hairs; adaxial surface glabrous; abaxial surface sparsely to densely covered with multicellular gland-headed hairs, sometimes also very sparsely unicellular-pubescent. Corolla pink to red-purple, with greenish spots on the upper 3 lobes, fragrant, zygomorphic, broadly rotate to funnelform, the tube much shorter than the limb and gradually expanding into it; upper corolla lobe 1-1.7 x 1-1.6cm; laterallobes 1.2-2.2x0.7-1.7cm; corolla tube 0.4-lcm long; outer surface of corolla glabrous; inner surface of corolla sparsely unicellular-pubescent towards base. Stamens 10, declinate, dimorphic, the upper 5, 0.8-1.7cm long, the lower 5, 2.2-3.3cm long, included to equalling corolla; filaments glabrous distally, becoming densely covered with flattened unicellular hairs proxi-mally, the shorter filaments more pubescent than the longer ones. Ovary 3-4mm long, moderately to densely covered with multicellular gland-headed hairs, sometimes with a few unicellular hairs at apex; style declinate, 2.4-3.4cm long, glabrous to unicellular-pubescent near base. Capsules ovoid, 0.8-1.3 x 0.5-0.7cm, moderately covered with multicellular gland-headed hairs, sometimes with a few unicellular hairs at apex. Seeds shiny and light brown, ellipsoid, 0.7-1.6x0.3-0.5mm; testa tightly appressed to body, with cells at each end elongated and fused to form ± stellate-globular tails 0.1-0.3mm long, the cells covering body elongate. Cotyledons lacking multicellular hairs or very occasionally with a few gland-headed hairs and with venation represented by midvein and a small number of poorly developed secondary veins.
Japan (Hokkaido, Honshu)
In coniferous or deciduous forests and thickets
Azalea albrechtii (Maxim.) Kuntze, Revis. Gen. PI. 2: 387 (1892). Type: Japan, Hakodate, in subalpine valley near Nodafu, 1861, C. Maximowicz (lecto. LE, n.v.).
Judd, W.S. & Kron, K.A. (1995) A Revision of Rhododendron VI. Subgenus Pentanthera (Sections Sciadorhodion, Rhodora and Viscidula). Edinburgh Journal of Botany 52(1):22