Phyllodoceae |
| The Phyllodoceae clade is not strongly supported by the
data (Figs. 4, 5, 6, 7, 8). The molecular analyses indicate two strongly
supported clades: Kalmia s.l.
(also including Leiophyllum and Loiseleuria) and a Phyllodoce clade (also
including Epigaea, Kalmiopsis, and Rhodothamnus). In the rbcL analysis,
these two clades are sister, but without parsimony jackknife support. The
matK data failed to resolve the Kalmia clade and the Phyllodoce clades
as sister. In both of the individual analyses Elliottia is unresolved with
respect to the remaining Ericoideae. But in the combined molecular analysis,
Elliottia is sister to the Kalmia + Phyllodoce clade. This relationship
is also indicated in the combined morphology and molecular tree (Fig.
7)
but without bootstrap support. With the exception of Elliottia and Epigaea,
the taxa that fall within the Phyllodoceae clade in this study have traditionally
been considered closely related (e.g., Stevens, 1971). Further studies
of the relationships of the Kalmia, Phyllodoce, and especially the Elliottia
clades are in progress. Phyllodoceae (as here defined) are characterized by their articulated pedicels (char. #37, but this character also occurs in Bryanthus, and may, therefore, be a synapomorphy for a Phyllodoceae + Bejarieae clade) and lack of abaxial calyx stomata (char. #43, but such stomata are present in Elliottia and Leiophyllum). The monophyly of this group, like that of the Bejarieae, is thus not well supported by morphology. Kalmiopsis and Phyllodoceae are linked by their distinctive multicellular hairs with biseriate stalks (chars. #23, 26) while Leiophyllum, Loiseleuria, and Kalmia are possibly linked by the presence of an exothecium (char. #67). The monophyly of a clade comprising Leiophyllum, Loiseleuria, and Kalmia (i.e., Kalmia s.l.) also has been strongly supported in a detailed phylogenetic analysis of this group (see Kron & King, 1996). |
Phyllodoceae |
Phyllodoceae Drude, Engl. & Prantl, Nat. Pflanzenfam. 4, 1: 31,
38. 1889. – Type genus: Phyllodoce Salisb. |
| Shrubs, evergreen, with alternate and spiral, decussate, or whorled, ericoid or non-ericoid leaves, entire to serrulate, convolute or revolute in bud. Leaf epidermal cells not lignified. Indumentum of glandular hairs and elongate non-glandular hairs, and sometimes papillae. Inflorescence terminal, rarely axillary, spicate, racemose, or corymbose, sometimes reduced; bracts, and paired ± basal, bracteoles usually present; calyx articulated with pedicel. Flowers 4—6-merous, actinomorphic. Calyx lobes variable in size, withering persistent or persistent; corolla sympetalous or choripetalous, rotate to urceolate, campanulate, the lobes small to large; stamens 5—10, included or exserted, the filaments straight to curved, unicellular-pubescent or smooth; anthers smooth or roughened, lacking appendages, dehiscing by slits or terminal pores. Pollen usually with viscin threads. Ovary 2—6-locular, with axile placentation; style impressed or not; stigma truncate, sometimes slightly expanded. Fruit a septicidal capsule, sometimes partly loculicidal as well; seeds with testa cells ± isodiametric to elongated; embryo with 2 cotyledons. |