title: Gelechiidae moths are capable of chemically dissolving the pollen of their host plants: first documented sporopollenin breakdown by an animal.
abstract: BACKGROUND
  Many insects feed on pollen surface lipids and contents accessible through the germination pores. Pollen walls, however, are not broken down because they consist of sporopollenin and are highly resistant to physical and enzymatic damage. Here we report that certain Microlepidoptera chemically dissolve pollen grains with exudates from their mouthparts.
  
  
  RESULTS
  Field observations and experiments in tropical China revealed that two species of Deltophora (Gelechioidea) are the exclusive pollinators of two species of Phyllanthus (Phyllanthaceae) on which their larvae develop and from which the adults take pollen and nectar. DNA sequences placed the moths and plants phylogenetically and confirmed that larvae were those of the pollinating moths; molecular clock dating suggests that the moth clade is younger than the plant clade. Captive moths with pollen on their mouthparts after 2-3 days of starvation no longer carried intact grains, and SEM photographs showed exine fragments on their proboscises. GC-MS revealed cis-β-ocimene as the dominant volatile in leaves and flowers, but GC-MS analyses of proboscis extracts failed to reveal an obvious sporopollenin-dissolving compound. A candidate is ethanolamine, which occurs in insect hemolymphs and is used to dissolve sporopollenin by palynologists.
  
  
  CONCLUSIONS
  This is the first report of any insect and indeed any animal chemically dissolving pollen.
authors.affiliation: Key Laboratory of Plant Resource Conservation and Sustainable Utilization, South China Botanical Garden, The Chinese Academy of Sciences, Guangzhou, China.
authors.forename: Shixiao
authors.initials: S
authors.lastname: Luo
authors.forename: Yongquan
authors.initials: Y
authors.lastname: Li
authors.forename: Shi
authors.initials: S
authors.lastname: Chen
authors.forename: Dianxiang
authors.initials: D
authors.lastname: Zhang
authors.forename: Susanne S
authors.initials: SS
authors.lastname: Renner
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D001704:Biopolymers / Q000378:metabolism*; D002338:Carotenoids / Q000378:metabolism*; D004463:Ecology; D019143:Evolution, Molecular; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D008018:Life Cycle Stages; D008297:Male; D009036:Moths / Q000033:anatomy & histology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029803:Phyllanthus / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D010802:Phylogeny; D011058:Pollen / Q000378:metabolism*; D013997:Time Factors
chemical_list: D001704:Biopolymers; C009800:sporopollenin; D002338:Carotenoids