Armament Imbalances: Match and Mismatch in Plant-Pollinator Traits of Highly Specialized Long-Spurred Orchids

Autor(es)

More, Marcela ^[1] ; Amorim, Felipe W. ^[2] ; Benitez-Vieyra, Santiago ^[1] ; Martin Medina, A. ^[1] ; Sazima, Marlies ; Cocucci, Andrea A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Nacl Cordoba, Consejo Nacl Invest Cient & Tecn, Inst Multidisciplinario Biol Vegetal, Lab Ecol Evolut & Biol Floral, RA-5000 Cordoba - Argentina

^[2] Univ Estadual Campinas, Inst Biol, Dept Biol Vegetal, Programa Posgrad Biol Vegetal, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: PLoS One; v. 7, n. 7 JUL 25 2012.
• Citações Web of Science: 22

Resumo

Background: Some species of long-spurred orchids achieve pollination by a close association with long-tongued hawkmoths. Among them, several Habenaria species present specialized mechanisms, where pollination success depends on the attachment of pollinaria onto the heads of hawkmoths with very long proboscises. However, in the Neotropical region such moths are less abundant than their shorter-tongued relatives and are also prone to population fluctuations. Both factors may give rise to differences in pollinator-mediated selection on floral traits through time and space. Methodology/Principal Findings: We characterized hawkmoth assemblages and estimated phenotypic selection gradients on orchid spur lengths in populations of three South American Habenaria species. We examined the match between hawkmoth proboscis and flower spur lengths to determine whether pollinators may act as selective agents on flower morphology. We found significant directional selection on spur length only in Habenaria gourlieana, where most pollinators had proboscises longer than the mean of orchid spur length. Conclusions/Significance: Phenotypic selection is dependent on the mutual match between pollinator and flower morphologies. However, our findings indicate that pollinator-mediated selection may vary through time and space according to local variations in pollinator assemblages. (AU)

• Processo FAPESP: 07/58666-3 - Diversidade, composição florística e biologia reprodutiva da comunidade de plantas esfingófilas de Floresta Ombrófila Densa Montana - Mata Atlântica, no sudoeste brasileiro
• Beneficiário: Felipe Wanderley de Amorim
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 03/12595-7 - Composição florística, estrutura e funcionamento da Floresta Ombrófila Densa dos Núcleos Picinguaba e Santa Virgínia do Parque Estadual da Serra do Mar, estado de São Paulo, Brasil
• Beneficiário: Carlos Alfredo Joly
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Temático