| Title: | 'Bleeding' flowers of Ceropegia gerrardii (Apocynaceae-Asclepiadoideae) mimic wounded insects to attract kleptoparasitic fly pollinators |
| Author(s): | Heiduk A; Brake I; Shuttleworth A; Johnson SD; |
| Address: | "Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville, Pietermaritzburg, 3209, South Africa. Monkeburgstr. 136, 31303, Burgdorf, Germany" |
| ISSN/ISBN: | 1469-8137 (Electronic) 0028-646X (Linking) |
| Abstract: | "Kleptomyiophily, where flowers imitate wounded insects to attract 'kleptoparasitic' flies as pollinators, is one of the most specialized types of floral mimicry and often involves physical trapping devices. However, the diversity of pollinators and functional floral traits involved in this form of mimicry remain poorly understood. We report a novel example of kleptomyiophily in the nontrapping flowers of Ceropegia gerrardii and explore the floral traits responsible for attracting pollinators. The pollinators, reproductive biology and floral traits (including epidermal surfaces, spectral reflectance and the composition of nectariferous petal secretions and scent) were investigated. Attractive volatiles were identified using electrophysiological and behavioural experiments. Ceropegia gerrardii was predominantly pollinated by kleptoparasitic Desmometopa spp. (Milichiidae) flies. The flower corollas extrude a protein- and sugar-containing secretion, similar to the haemolymph of wounded insects, on which the flies feed. Floral scent was chemically similar to that of injured honey bees. Four out of 24 electrophysiologically active compounds, all released by injured honey bees, were identified as key players in pollinator attraction. Our results suggest that C. gerrardii flowers chemically mimic wounded honey bees to attract kleptoparasitic flies and reward them with a secretion similar to the haemolymph on which they would normally feed" |
| Keywords: | Bees Animals *Diptera/physiology *Apocynaceae Pollination/physiology Insecta/physiology Pheromones Flowers/physiology Brachystelma behavioural trap electroantennographic detection floral scent fly-pollination haemolymph mimicry honey bee mimicry; |
| Notes: | "MedlineHeiduk, Annemarie Brake, Irina Shuttleworth, Adam Johnson, Steven D eng Research Support, Non-U.S. Gov't England 2023/03/21 New Phytol. 2023 Aug; 239(4):1490-1504. doi: 10.1111/nph.18888. Epub 2023 Apr 4" |
