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Phylogeny and radiation of pollination systems in DISA (Orchidaceae).
We studied the patterns of adaptive radiation in Disa, a large orchid genus in southern Africa. A cladogram for 27 species was constructed using 44 morphological characters. Pollination systems wereExpand
Molecular Phylogenetic and Evolutionary Studies of Parasitic Plants
The parasitic nutritional mode is a frequently evolved adaptation in animals (Price, 1980), as well as in flowering plants (Kuijt, 1969). Heterotrophic angiosperms can be classified as eitherExpand
Phylogeny and biogeography ofOrobanchaceae
Orobanchaceae, as it is currently defined, includes all levels of parasitic ability ranging from nonparasitic (Lindenbergia) to facultative and obligate hemiparasites to obligate holoparasites.Expand
LONG‐TONGUED FLY POLLINATION AND EVOLUTION OF FLORAL SPUR LENGTH IN THE DISA DRACONIS COMPLEX (ORCHIDACEAE)
  • S. Johnson, K. Steiner
  • Biology, Medicine
  • Evolution; international journal of organic…
  • 1 February 1997
Field studies in South Africa showed that floral spur length in the Disa draconis complex (Orchidaceae) varies enormously between populations in the southern mountains (means = 32–38 mm), lowlandExpand
Oil Collecting Bees Mostly of the Summer Rainfall Area of Southern Africa (Hymenoptera: Melittidae: Rediviva)
Abstract The species of Rediviva (Apoidea, Melittidae) occurring in the summer rainfall region of South Africa are revised. Nine species are recognized, four are described as new: R. brunnea, R.Expand
POLLINATOR ADAPTATION TO OIL‐SECRETING FLOWERS—REDIVIVA AND DIASCIA
OIL FLOWERS AND OIL BEES: FURTHER EVIDENCE FOR POLLINATOR ADAPTATION
We examined foreleg length and body size variation in two species of oil‐collecting bees (Rediviva; Melittidae) in southern Africa. Oil‐collecting bees harvest oil from host flowers by rubbing theirExpand
Floral and pollinator divergence in two sexually deceptive South African orchids
Two sister species in Disa section Disa were studied to evaluate the effect that minor differences in floral color, shape, and scent have on pollination. D. atricapilla and D. bivalvata haveExpand
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