Collabieae (Orchidaceae) is a long neglected tribe with confusing tribal and generic delimitation and little-understood phylogenetic relationships. Using plastid
matK,
psaB,
rbcL, and
trnH-
psbA DNA sequences and morphological evidence, the phylogenetic relationships within the tribe Collabieae were assessed as a basis for revising their tribal and generic delimitation. Collabieae (including the previously misplaced mycoheterotrophic
Risleya) is supported as monophyletic and nested within a superclade that also includes Epidendreae, Podochileae, Cymbidieae and Vandeae.
Risleya is nested in Collabiinae and sister to
Chrysoglossum, a relationship which, despite their great vegetative differences, is supported by floral characters.
Ania is a distinct genus supported by both morphological and molecular evidence, while redefined
Tainia includes
Nephelaphyllum and
Mischobulbum.
Calanthe is paraphyletic and consists four clades; the genera
Gastrorchis,
Phaius and
Cephalantheropsis should be subsumed within
Calanthe.
Calanthe sect.
Ghiesbreghtia is nested within sect.
Calanthe, to which the disputed
Calanthe delavayi belongs as well. Our results indicate that, in Collabieae, habit evolved from being epiphytic to terrestrial.
相似文献