Dataset for: Short flowers for long tongues: functional specialization in a nocturnal pollination network of an asclepiad in long-tongued hawkmoths (Biotropica)

Since Darwin, very long and narrow floral tubes have been known to
represent the main floral morphological feature for specialized
long-tongued hawkmoth pollination. However, specialization may be driven
by other contrivances instead of floral tube morphology. Asclepiads are
plants with a complex floral morphology where primary hawkmoth pollination
had never been described. We detailed here the intricate pollination
mechanism of the South American asclepiad Schubertia grandiflora, where
functional specialization on long-tongued hawkmoth pollinators occurs
despite the short floral tube of this species. We studied two plant
populations in the Brazilian Cerrado and recorded floral visitors using
different approaches, such as light-trapped hawkmoths for pollen analysis,
direct field observations, and IR motion-activated cameras. Finally, using
a community-level approach we applied an ecological network analysis to
identify the realized pollinator niche of S. grandiflora among the
available niches in the pollinator community. Throughout a period of 17
years, long-tongued hawkmoths were consistently recorded as the main
floral visitors and the only effective pollinators of S. grandiflora.
Flowers rely on highly modified corona and gynostegium, and enlarged
nectar chambers, to drive visitors and pollination mechanism. Despite
relatively short-tube, network analysis placed S. grandiflora in the
module including exclusively long-tongued hawkmoth pollinators and the
most phenotypically specialized sphingophilous plants in the community.
These results represent the first example of functional specialization in
long-tongued hawkmoths in an asclepiad species. However, this
specialization is uncoupled from the long floral tubes historically
associated with the sphingophily syndrome.