Adaptations for insect-trapping in brood-site pollinated Colocasia (Araceae)

Author(s)
David Bröderbauer, Silvia Ulrich, Anton Weber
Abstract

The Araceae include both taxa with rewarding and deceptive trap pollination systems. Here we report on a genus in which rewarding and imprisonment of the pollinators co-occur. We studied the pollination of four species of Colocasia in Southwest China and investigated the morpho-anatomical adaptations of the spathe related to the attraction and capture of pollinators. All four species were pollinated by drosophilid flies of the genus Colocasiomyia. The flies are temporally arrested within the inflorescence and departure is only possible after pollen release. Trapping of the flies is accomplished by the closure of the spathe during anthesis. Moreover, in two species the spathe is covered with papillate epidermal cells known to form slippery surfaces in deceptive traps of Araceae. However, in Colocasia the papillae proved not slippery for the flies. The morpho-anatomical properties of the spathe epidermis indicate that it is an elaborate osmophore and serves for the emission of odours only. Despite its similarity to deceptive traps of other aroids, Colocasia and Colocasiomyia have a close symbiotic relationship, as the attracted flies use the inflorescence as a site for mating and breeding. The trap mechanism has presumably evolved independently in Colocasia and is supposed to facilitate more efficient pollen export.

Organisation(s)
Journal
Plant Biology
Volume
16
Pages
659-668
No. of pages
10
ISSN
1435-8603
DOI
https://doi.org/10.1111/plb.12081
Publication date
09-2013
Peer reviewed
Yes
Austrian Fields of Science 2012
106049 Ultrastructure research, 106008 Botany, 106029 Plant morphology
Keywords
ASJC Scopus subject areas
Ecology, Evolution, Behavior and Systematics, Plant Science
Portal url
https://ucris.univie.ac.at/portal/en/publications/adaptations-for-insecttrapping-in-broodsite-pollinated-colocasia-araceae(ca4e70c6-2c17-4d94-8d5d-d08883f2ecc9).html