Figure 1.
Flower morphology of three South American Habenaria species and place of pollinaria attachment onto the pollinator’s head.
A) Lateral view of H. gourlieana flower depicting the general morphology of the three long-spurred Habenaria species studied. Detail of the rostellum morphology (r), position of the viscidia (arrow heads) and stigmatic surfaces (s) in B) H. gourlieana; C) H. johannensis and D) H. paulistana. E) H. gourlieana pollinaria attached to the fore margin of Manduca sexta eye. F) H. johannensis pollinaria attached to the palps of a M. brasiliensis moth. G) H. paulistana pollinaria attached to the posterior lower margin of Eumorpha obliquus eye after manually contacting the hawkmoth head to the floral column. Scale bar equals 1 cm.
Table 1.
Hawkmoth species captured during flowering season in the studied populations.
Figure 2.
Match and mismatch between the lengths of orchid spurs and pollinators’ proboscises.
Black bars show spur length distributions in the three Habenaria species and grey bars the corrected histograms according to the mean height of the nectar column within the spur. The vertical black lines in the x axis show the proboscis lengths of all captured hawkmoths, circles represent individuals from those species seen either visiting flowers (filled) or captured carrying pollinaria attached to their eyes (open).
Figure 3.
Cubic spline regressions between floral traits (spur length and number of flowers) and reproductive success (exported pollinaria) in three orchid species.
Habenaria gourlieana: A & B. H. paulistana: C. H. johannensis: D. Dotted lines show ±1 Bayesian standard errors.
Table 2.
Mean and standard deviations of reproductive success estimates in three species of Habenaria.
Table 3.
Multivariate phenotypic selection on spur length and flower number through male (number of exported polinaria per plant) and female (number of fruits) functions in Habenaria gourlieana, H. johannensis and H. paulistana.