Orthoptera, a new order of pollinator
Open Access
- 11 January 2010
- journal article
- research article
- Published by Oxford University Press (OUP) in Annals of Botany
- Vol. 105 (3), 355-364
- https://doi.org/10.1093/aob/mcp299
Abstract
Pollinator-mediated selection and evolution of floral traits have long fascinated evolutionary ecologists. No other plant family shows as wide a range of pollinator-linked floral forms as Orchidaceae. In spite of the large size of this model family and a long history of orchid pollination biology, the identity and specificity of most orchid pollinators remains inadequately studied, especially in the tropics where the family has undergone extensive diversification. Angraecum (Vandeae, Epidendroideae), a large genus of tropical Old World orchids renowned for their floral morphology specialized for hawkmoth pollination, has been a model system since the time of Darwin. The pollination biology of A. cadetii, an endemic species of the islands of Mauritius and Reunion (Mascarene Islands, Indian Ocean) displaying atypical flowers for the genus (white and medium-size, but short-spurred) was investigated. Natural pollinators were observed by means of hard-disk camcorders. Pollinator-linked floral traits, namely spur length, nectar volume and concentration and scent production were also investigated. Pollinator efficiency (pollen removal and deposition) and reproductive success (fruit set) were quantified in natural field conditions weekly during the 2003, 2004 and 2005 flowering seasons (January to March). Angraecum cadetii is self-compatible but requires a pollinator to achieve fruit set. Only one pollinator species was observed, an undescribed species of raspy cricket (Gryllacrididae, Orthoptera). These crickets, which are nocturnal foragers, reached flowers by climbing up leaves of the orchid or jumping across from neighbouring plants and probed the most ‘fresh-looking’ flowers on each plant. Visits to flowers were relatively long (if compared with the behaviour of birds or hawkmoths), averaging 16·5 s with a maximum of 41·0 s. At the study site of La Plaine des Palmistes (Pandanus forest), 46·5 % of flowers had pollen removed and 27·5 % had pollinia deposited on stigmas. The proportion of flowers that set fruit ranged from 11·9 % to 43·4 %, depending of the sites sampled across the island. Although orthopterans are well known for herbivory, this represents the first clearly supported case of orthopteran-mediated pollination in flowering plants.Keywords
This publication has 36 references indexed in Scilit:
- Major Evolutionary Transitions in Flowering Plant Reproduction: An OverviewInternational Journal of Plant Sciences, 2008
- Elevational gradients of species diversity, breeding system and floral traits of orchid species on Réunion IslandJournal of Biogeography, 2005
- Pollination Syndromes and Floral SpecializationAnnual Review of Ecology, Evolution, and Systematics, 2004
- Floral scent emission and pollinator attraction in two species of Gymnadenia (Orchidaceae)Oecologia, 2004
- Homing behaviour of juvenile Australian raspy crickets (Orthoptera: Gryllacrididae)Physiological Entomology, 2004
- Allele substitution at a flower colour locus produces a pollinator shift in monkeyflowersNature, 2003
- The Gryllacrididae: an overview of the world fauna with emphasis on Australian examples.Published by CABI Publishing ,2001
- Generalization versus specialization in plant pollination systemsTrends in Ecology & Evolution, 2000
- The reproductive biology and genetics of island plantsPhilosophical Transactions B, 1996
- Pollination Systems, Dispersal Modes, Life Forms, and Diversification Rates in Angiosperm FamiliesEvolution, 1992