Biology Reference
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Fig. 7.2 ( a ) Epidendrum magnoliae , flower, front view; ( b ) Hexalectris spicata , flower, oblique
view, scale bars = 5 mm
Epidendrum L.
Over 1,000 tropical and subtropical species of Epidendrum have been described
(Hagsater 2002 ). Seven are present in North America north of Mexico. Among
these, E. magnoliae Muhlenberg (green-fly orchid) (Fig. 7.2a ) is the only represen-
tative of the genus and the only epiphytic orchid found naturally north of Florida
(Luer 1972 ; Correll 1978 ). It occurs in swamps, hammocks, and moist hardwood
forests along the Atlantic and Gulf Coasts from North Carolina into Florida and
west to Louisiana (Luer 1972 ; Hagsater 2002 ).
Although much information is available on tropical and subtropical species of
the genus, no studies have been published which specifically treat the reproductive
biology of E. magnoliae "USHAND+UTZ 2006 ) detected genetic drift within and
high levels of gene flow between populations, a finding they attributed to pollinator
movement as well as seed dispersal. The flowers are said to be intensely fragrant at
night (Subrahmanyam 2004 ), and the odor is described as honey-like. This, along
with the morphology of the flower (van der Pijl and Dodson 1966 ; Luer 1972 ), sug-
gests pollination by nocturnal moths. Adams and Goss ( 1976 ) and Goss ( 1977 )
described such a syndrome for two other species, E. amphistomum !2ICHARDAS
E. anceps Jacquin) and E. floridense Hagsater (as E. difforme Jacquin) in the Big
Cypress Swamp of southern Florida (synonymy based on Hagsater 2002 ). Both are
self-incompatible and therefore obligately xenogamous. Although nectar is pro-
vided, the initial attraction in these species may be pheromone-like since the flowers
are pollinated almost exclusively by male moths.
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