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孢粉素（sporonpollenin）是孢子和花粉外壁的主要成分，主要由脂肪酸及碳水化合物構成，但是其準確的結構仍然不清楚。孢粉素的性質(zhì)堅固，能抗化學(xué)及生物分解，同時(shí)也不溶于無(wú)機和有機溶劑。孢粉素的這種特性是孢粉化石能保存上百萬(wàn)年的主要原因。雖然許多昆蟲(chóng)取食花粉表面的脂類(lèi)或通過(guò)花粉萌發(fā)孔獲得花粉內的營(yíng)養成分，但是到目前為止沒(méi)有任何動(dòng)物能破壞孢粉壁。
中科院華南植物園系統與進(jìn)化生物學(xué)研究領(lǐng)域張奠湘研究組的羅世孝博士等對葉下珠科的越南葉下珠（Phyllanthus cochinchinensis）和水油甘（P. rheopyticus）開(kāi)展傳粉生態(tài)學(xué)研究發(fā)現，兩種未被描述的角麥蛾(Deltophora) sp.1和sp.2分別是越南葉下珠和水油甘的唯一傳粉昆蟲(chóng)。兩種葉下珠屬植物與傳粉角麥蛾之間形成了兩對專(zhuān)性互利傳粉關(guān)系。角麥蛾在訪(fǎng)問(wèn)植物雄花時(shí)吸取花蜜及收集花粉，在訪(fǎng)問(wèn)雌花時(shí)會(huì )為植物完成傳粉。角麥蛾成蟲(chóng)以寄主植物的花蜜和花粉為食，并產(chǎn)卵于寄主植物上，其幼蟲(chóng)以取食寄主植物嫩葉為發(fā)育營(yíng)養，而寄主植物依賴(lài)其唯一的傳粉昆蟲(chóng)來(lái)完成傳粉，傳粉者與寄主植物間形成了一對一互利共生關(guān)系。
對角麥蛾研究最令人驚奇的發(fā)現是，角麥蛾口器分泌的一種分泌物能分解孢粉素和融解花粉。這是首次發(fā)現有昆蟲(chóng)（甚至可以說(shuō)動(dòng)物）能分解孢粉素和融解花粉。同時(shí)還發(fā)現，傳粉昆蟲(chóng)角麥蛾不但具有特殊的訪(fǎng)花行為，而且具有獨特的口器結構。角麥蛾特殊的訪(fǎng)花行為和獨特的昆蟲(chóng)口器結構，為專(zhuān)性互利共生物種間往往演化出獨特的行為與特殊的適應結構又提供了一個(gè)新的案例。
這一新的發(fā)現剛剛在線(xiàn)發(fā)表在科學(xué)雜志PLoS ONE上。這是繼羅世孝博士及其合作者在2010年發(fā)現基部被子植物“八角屬植物與傳粉癭蚊協(xié)同進(jìn)化（Luo et al. 2010, Am. J. Bot. 97: 1220-1228）”后在植物與傳粉昆蟲(chóng)協(xié)同進(jìn)化研究方面的又一重要發(fā)現。

原文出處：
PLoS ONE 6(4): e19219. doi:10.1371/journal.pone.0019219
Gelechiidae Moths Are Capable of Chemically Dissolving the Pollen of Their Host Plants: First Documented Sporopollenin Breakdown by an Animal
Shixiao Luo1, Yongquan Li1, Shi Chen1, Dianxiang Zhang1*, Susanne S. Renner2*
1 Key Laboratory of Plant Resource Conservation and Sustainable Utilization, South China Botanical Garden, The Chinese Academy of Sciences, Guangzhou, China, 2 Department of Biology, University of Munich (LMU), Munich, Germany
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.
Methodology/Principal Findings
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 **s 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 **yses 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/Significance
This is the first report of any insect and indeed any animal chemically dissolving pollen.

A角麥蛾訪(fǎng)雄花；B角麥蛾訪(fǎng)雌花；C角麥蛾幼蟲(chóng)取食寄主嫩葉；D角麥蛾口器上攜帶寄主植物花粉；E角麥蛾獨特口器上完整的花粉和分解的花粉塊。