Pollen morphology and systematics in two subfamilies of the Ericaceae : Pyroloideae and Monotropoideae

Phylogeny of Pyroleae (Ericaceae): implications for character evolution

“…Orthilia is characterized by monad pollen (i.e., pollen grains are separated from each other), unlike the tetrad pollen found in Pyrola and Moneses and polyad pollen (i.e., adjacent tetrads are loosely connected to each other) found in Chimaphila (Erdtman 1952;Nowicke 1966;Takahashi 1988). Warner and Chinnappa (1986) and Freudenstein (1999) suggested that the monad pollen of Orthilia is apomorphic rather than plesiomorphic and the monads result from the breakup of tetrads.…”

“…Instead, we wanted to better understand the pattern of evolution of those characters traditionally considered important in the classification of the tribe. Therefore, states for thirteen morphological characters were scored based on observations from herbarium specimens, a reading of the relevant literature (e.g., Henderson 1919;Copeland 1947;Křísa 1971;Haber and Cruise 1974;Takahashi 1988;Anderberg 1994) and our experiences working with this group. The thirteen discrete morphological characters and their respective character states are summarized in Table 1.…”

“…Knaben and Engelskjøn (1968) inferred that the pattern of chromosome number evolution within Pyroleae successively decreases from Pyrola (2n = 46) through Orthilia (2n = 38) to Moneses (2n = 26) and Chimaphila (2n = 26). On the basis of palynological evidence Warner and Chinnappa (1986) and Takahashi (1988) concluded that the characteristics of the monad pollen within Orthilia is a plesiomorphy and proposed an evolutionary trend from Orthilia through Pyrola and Moneses to Chimaphila, in which pollen exine sculpture changes from verrucate through reticulate to psilate. Mainly based on a series of morphological characters, two groups of Moneses-Chimaphila and Orthilia-Pyrola were identified by Křísa (1971), Haber and Cruise (1974) and Freudenstein (1990).…”

“…5 species), Pyrola (ca. 30 species) as well as the two monotypic genera Moneses and Orthilia (Haber and Cruise 1974;Takahashi 1988;Qin and Stevens 2005). They are found in patches in the understories of temperate coniferous forests in the Northern Hemisphere-most frequently in coniferous forest, but sometimes in deciduous ones.…”

A test of four candidate barcoding markers for the identification of geographically widespreadChimaphilaspecies (Pyroleae, Ericaceae)

“…Specimens in this genus can be easily recognized by their congested, alternate leaf arrangement, coriaceous leaf laminae, congested racemes of nodding flowers that may be erect at anthesis, obconic short styles and stigmas that are wet when receptive, and dry capsular fruit, and leathery leaf blade, nodding flowers, obconic very short style and erect capsules, respectively (Qin and Stevens 2005). However, the lack of knowledge about geographic origin and limited morphological variation make species identification difficult (Takahashi 1988;Z.W. Liu, pers.…”