Rhodoreae

Morphological synapomorphies supporting the Rhodoreae include the flowers on shoots of the previous season (char. #30), ovoid to cylindric fruits (char. #83), and the presence of gossypetin (char. #87).Rhodoreae have zygomorphic flowers with spots or a blotch (chars. #33, 47), and it is probably significant that these features are both found in Therorhodion, which is the sister taxon to the rest of the clade. It is probable that zygomorphic corollas evolved only once (in
the common ancestor of Rhodoreae) and have been lost several times within this clade. Although this hypothesis is less parsimonious (based on the results presented here) than an assumption of parallelism, the hypothesis of multiple losses is preferred based on an analysis employing more taxa within this group (Kron & Judd, 1990). A major subgroup of Rhodoreae is diagnosed by scarious inflorescence bracts (char. #38), forming the perulate inflorescence characterizing the
species-rich Rhododendron clade (which includes Tsusiophyllum and Menziesia). The base chromosome number of 13 also characterizes the Rhododendron clade.
Rhodoreae

Rhodoreae DC. ex Duby, Bot. Gall. 1: 318. 1828 (as Rhodoraceae). - Type genus Rhodora L. (= Rhododendron L.)
Diplarcheae Airy Shaw, Kew Bull., 17: 509. 1964.
Ledeae Rchb.f. in Rchb., Icon. Fl. Germ. Helv. 17: 78.
1854-1855.
Ledinae Benth. in DC., Prodr. 7: 729. 1839 (as Ledeae).
Menziesieae K. Koch, Hort. Dendrol. 2: 340. 1854 (as
Menziesiaceae).
Rhododendrinae Benth. in DC., Prodr. 7: 712. 1839 (as
Rhododendreae).
Shrubs or small trees, evergreen or deciduous, with alternate, non-ericoid, entire to serrulate-ciliate leaves, convolute or revolute in bud. Leaf epidermal cells not lignified. Indumentum very variable, sometimes glandular, peltate, or highly branched. Inflorescence terminal or rarely axillary, usually corymbose or umbellate; bracts present, usually as perulae (except Therorhodion where bracts are green), bracteoles paired, usually ± basal; calyx articulated with
pedicel or not. Flowers usually 4- or 5-merous, slightly zygomorphic, but occasionally secondarily actinomorphic. Calyx lobes variably developed, persistent or deciduous; corolla usually sympetalous, variously shaped, often with spots or blotches, the lobes usually
moderate to large; stamens 5-15, included or exserted, the filaments straight to curved, unicellular-pubescent or smooth; anthers smooth, lacking spurs, dehiscing by terminal pores to elongate slits. Pollen with viscin threads. Ovary 3-14-locular, with aile placentation,
superior; style impressed or not; stigma truncate or expanded. Fruit an ovoid to cylindric septicidal capsule; seeds with testa cells usually elongated; embryo with 2 cotyledons.
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