Thursday, April 6, 2017

[Ecology • 2017] A Novel, Enigmatic Basal Leafflower Moth Lineage Pollinating A Derived Leafflower Host Illustrates the Dynamics of Host Shifts, Partner Replacement, and Apparent Coadaptation in Intimate Mutualisms


Flowers, fruit, and pollinator of Glochidion lanceolarium. 


Abstract
Leafflower plant/leafflower moth brood pollination mutualisms are widespread in the Paleotropics. Leafflower moths pollinate leafflower plants, but their larvae consume a subset of the hosts’ seeds. These interactions are highly phylogenetically constrained: six clades of leafflower plants are each associated with a unique clade of leafflower moths (Epicephala). Here, we report a previously unrecognized basal seventh pollinating Epicephala lineage—associated with the highly derived leafflower clade Glochidion—in Asia. Epicephala lanceolaria is a pollinator and seed predator of Glochidion lanceolarium. Phylogenetic inference indicates that the ancestor of E. lanceolaria most likely shifted onto the ancestor of G. lanceolarium and displaced the ancestral allospecific Epicephala pollinator in at least some host populations. The unusual and apparently coadapted aspects of the G. lanceolarium/E. lanceolaria reproductive cycles suggest that plant-pollinator coevolution may have played a role in this displacement and provide insights into the dynamics of host shifts and trait coevolution in this specialized mutualism.

Keywords: EpicephalaGlochidion, host shift, intimate mutualism, specialized pollination, coadaptation.


Figure 1: Flowers, fruit, and pollinator of Glochidion lanceolarium.
 
AGlochidion lanceolarium individual bearing many fruits and flower buds. B, Male flower. C, Female flowers. D, Female Epicephala lanceolaria moth visiting a male flower. EEpicephala lanceolaria actively pollinating a female flower. F, Ovipositing E. lanceolariaG, Pollinated stigma, showing the pollen grains on the stigma. H, Cross section of a female flower with three eggs (arrows). I, Proboscis of a female E. lanceolaria moth bearing pollen. J, Epicephala lanceolaria pupa in a carpel chamber without cocoon. KEpicephala lanceolaria cocoon in a carpel chamber with a pupa inside. L, Cross section of a mature fruit with two eclosed E. lanceolaria in the carpel chamber.
DOI:  10.1086/690623 




Shi-Xiao Luo, Gang Yao, Ziwei Wang, Dianxiang Zhang and David H. Hembry. 2017. A Novel, Enigmatic Basal Leafflower Moth Lineage Pollinating A Derived Leafflower Host Illustrates the Dynamics of Host Shifts, Partner Replacement, and Apparent Coadaptation in Intimate Mutualisms. The American Naturalist.   DOI:  10.1086/690623

http://www.amnat.org/an/newpapers/AprLuo.html
The Pollination Mutualism between Epicephala moths of Gracillariidae and Glochidion plants of Euphorbiaceae