Visitors to Southeastern Hawkmoth Flowers

Abstract

- Despite global concern for the status of animal pollinators, studies on pollination systems in the southeastern United States are disproportionately low compared to the diversity of this region. For example, sphingophilous, or hawkmoth-attracting plants, occur in the southeastern US, but confi rmation is lacking for the large, long-tongued hawkmoths predicted to visit these fl owers by previous researchers. Hymenocallis coronaria (Shoals Spider Lily, or Cahaba Lily), H. occidentalis (Woodland Spider Lily), Oenothera biennis (Common Evening Primrose), and O. grandifl ora (Large-fl owered Evening Primrose) were studied to confi rm this prediction. Manduca rustica (Rustic Sphinx) was confi rmed as a frequent visitor to all four plant species studied. M. sexta (Carolina Sphinx) was confi rmed for three of the four plants. To determine the range of animal visitors to these plants, three of the plant species were observed during day- and night-observation periods, and total visitation was compared between these times. For H. coronaria, fl ower-visitation rates did not differ between day and night periods. H. occidentalis and O. biennis were visited signifi cantly more during night hours than during the day. Although hawkmoths are frequent visitors to H. occidentalis and O. biennis, and are probably their most effi cient pollinators, Archilochus colubris (Ruby