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Glochidion (Phyllanthaceae; leafflower trees) is a genus of trees which is widely reported to be pollinated by leafflower moths (Gracillariidae: Epicephala) in temperate and subtropical Asia, Australia, and the Pacific islands. However, the pollination ecology of Glochidion is not well described from tropical Asia, the region where it is most species-rich at both local (≤9 spp.) and regional (~200 spp.) scales. Here we report investigations of pollination biology and species-specificity of five Glochidion species in tropical Southeast Asia (Cambodia). Through nocturnal observations and fruit dissections, we find that at least three and likely five Glochidion species in Cambodia are pollinated by seed-parasitic leafflower moths. We find no evidence that any of these leafflower moths are non-mutualistic parasites, despite known examples of such parasites of this mutualism elsewhere in Asia. While the presence of a single larva in a fruit results in only a fraction of seeds being consumed, the presence of more than one larva per fruit—a frequent occurrence in some species—can result in almost all seeds within the fruit being infested. Multilocus phylogenetic analysis indicates that there are five different minimally monophyletic leafflower moth clades, each of which pollinates a unique Glochidion host species. Our results indicate that in its center of diversity in tropical Asia this system is an obligate pollination mutualism as previously described at the global margins of its distribution. These findings provide insights into the processes that generate and maintain biodiversity and maintain mutualism stability in plant–insect interactions in this biodiversity hotspot.

A comprehensive taxonomic revision of the genus Glochidion J.R. Forst. & G. Forst. from Taiwan in China was carried out based on the examination of herbarium specimens and filed investigations. Eight species and three varieties are recognized, including a new species endemic to Taiwan, G. lanyuense Gang Yao & S.X. Luo, which is described and illustrated. Three names, viz. G. chademenosocarpum Hayata, G. kusukusense Hayata, and G. ovalifolium F.Y. Lu & Y.S. Hsu, are reduced to the new synonyms of G. rubrum Blume, G. lanceolatum Hayata, and G. ellipticum Wight, respectively. Two names, viz. G. lanceolatum Hayata and G. suishaense Hayata, are lectotypified here. A key to the Glochidion species in Taiwan is provided.

Based on morphological studies performed on live plants in the field and specimens deposited in herbaria, a new species, Glochidionshanense Gang Yao & Shixiao Luo (Phyllantheae, Phyllanthaceae), is here described and illustrated. The species is morphologically most similar to G.ellipticum Wight, but can be distinguished from the latter by having hairy branchlets, longer pedicels, uniseriate and narrowly triangular sepals of female flowers, 4–5-locular ovaries, stout and cylindric persistent style on fruits.

Background and Aims Resin is a defence against herbivores and a floral reward in a few African and South American species whose bee pollinators collect it for nest construction. Here we describe a new role for floral resin from the Asian genus Kadsura (Schisandraceae). Kadsura tepals tightly cover a globe formed by carpels (in females) or near-fused stamens with fleshy connectives (in male flowers of most, but not all species). Methods We carried out field observations at four sites in China and used pollinator behavioural assays, chemical analyses and time-calibrated insect and plant phylogenies to investigate the specificity of the interactions and their relationship to floral structure. Key Results Nocturnal resin midges (Resseliella, Cecidomyiidae) walk around on the flowers’ sexual organs to oviposit, thereby transferring pollen and wounding tissues. The larvae then develop in resin-filled chambers. Male and female floral scents are dominated by α-pinene, while the resinous exudate is dominated by caryophyllene. As revealed by barcoding of multiple midge larvae per flower species, the mutualisms are species specific and appear to have evolved over the past 6–9 million years. Conclusions Resin feeding, not pollen or ovule feeding, by midge larvae explains the abundant Kadsura exudates, highlighting the poorly known world of nocturnal flower–fly interactions.

The globally distributed family Phyllanthaceae comprises 1745 species, all of which produce unisexual flowers, and most of the species occur in the tropics. The few species in which the pollination system has been studied are pollinated by flies, wasps, or specialized moths, and at least two species are duodichogamous. Here we report on the flowering phenology and pollination of the Chinese species Bridelia stipularis and Cleistanthus sumatranus, which were studied on the tropical Hainan Island. Both species are duodichogamous and indicated to be fly-pollinated. The calliphorid species Chrysomya megacephala, Isomyia isomyia, Pierretia sp., Hemipyrellia sp., and Achoetandrus tufifacies were the most frequent flower visitors to B. stipularis; some of these species together with syrphids (Meliscaeva cinctella, Dideopsis sp., and Eristalis sp.) were the most abundant visitors to Cl. sumatranus flowers. Fruit set in hand-pollinated flowers was higher than in open-pollinated flowers, but because of natural fruit abortion the difference was not significant, indicating that fly pollinators do not limit reproduction of these Phyllanthaceae species. This study provides an addition to the limited Asian literature on pollination by flies and the even more limited literature on duodichogamy. It could help to broaden our understanding for analysis of the evolution of duodichogamy in future research, but the specific ecological factors behind the evolution of this rare sexual system are still difficult to generalize.

Phyllanthus comprises approximately 1,270 species, making it one of the world's largest plant genera. Molecular data so far are of limited value for understanding Phyllanthus because of the sheer size of the genus. They can, however, help sort-out cryptic species and provide information on the origin of suspected introduced species. One of the seemingly most widespread species is P. reticulatus, which has been recorded from Asia, Australia, Africa, and Jamaica. The name is based on a mixed collection from tropical Asia now in the Lamarck herbarium, and we lectotypify it here. We use nuclear ITS sequences to test the broad treatment of P. reticulatus in recent floras, identify records of “P. reticulatus” from Africa, and investigate the origin of P. reticulatus on Jamaica. A maximum likelihood tree for accessions of P. reticulatus from throughout its supposed range (plus relevant outgroups) shows that the Jamaican plants represent the Asian species, that the African plants called P. reticulatus be...

 Premise of the study : Flower heating is known from a few species in 11 of the c. 450 families of flplants. Flowers in these families produce heat metabolically and are adapted to beetles or fl as pollinators. Here, we focus on the Schisandraceae, an American/Asian plant family known to exhibit fl ower heating in some species, but not others, raising the question of the adaptive function of heat production.  Methods : We used fi eld observations, experiments, and ancestral trait reconstruction on a molecular phylogeny for Schisandraceae that includes the investigated species.  Key results : At least two Chinese species of Illicium are exclusively pollinated by gall midges that use the fl owers as brood sites (not for pollen feeding). Continuous monitoring of fltemperatures revealed that the highest temperatures were attained after the fl owers ’ sexual functions were over, and experiments showed that post-anthetic warming benefi ted larval development, not fruit development. Midge larvae in flwith trimmed tepals (and hence a lower temperature) died, but fruit set ratios remained unchanged. Based on the DNA phylogeny, gall midge pollination evolved from general fl y/beetle pollination several times in Schisandraceae, with some species adapted to flmidges, others to pollen-feeding midges.  Conclusions : Flower heating may be an ancestral trait in Schisandraceae that became co-opted in species pollinated by fl breeding midges requiring long-persistent warm chambers for larval development.

• Background and Aims Oxalis debilis is a South American tristylous species that is currently naturalizing in China. Based on field observations and herbarium data a report is made on its pollination, morph frequencies, pollen viability, seed set and chromosome number. In addition, a new chromosome count for the species in Africa is provided. • Methods Field observations were conducted in six provinces in south-east China. Flower visitors were recorded and nectar sugar was measured with a refractometer. The species' compatibility system was determined by carrying out experimental self- and cross-pollinations on bagged inflorescences. Stigma receptivity and pollen viability was determined using the MTT test. • Key Results and Conclusions Populations of O. debilis in China contain either the mid-style-length morph or the short morph, but not both. Pollination is by nectar- and pollen-foraging bees; pollen viability is low; and seed set in natural and experimentally self- or cross-pollinated flowers is extremely low. Chromosome counts indicate that O. debilis contains diploid and tetraploid forms in its native as well as introduced range, which does not support a previous hypothesis that the predominant vegetative reproduction in this species is an escape from pentaploidy.

Orchidantha yunnanensis, a new species from Malipo county in Yunnan, China, is described and illustrated. The identity of Orchidantha laotica, originally described from herbarium material, is discussed here, and a colour plate of this species based on recent collections from Laos is included.

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 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-b-ocimene as the dominant volatile in leaves and flowers, but GC-MS analyses of proboscis extracts failed to reveal an obvious sporopollenindissolving 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.

Flowering plants commonly separate male and female function in time, but rarely are the two stages synchronized within and among individuals. One such temporal mating system is duodichogamy in which each plant produces two batches of male flowers that are temporally separated by a batch of female flowers, with within-individual synchrony and among-individual asynchrony to ensure mating partners. Duodichogamy is known only from a few species in four genera in unrelated families. We report on duodichogamy in the Chinese tree species Bridelia tomentosa (Phyllanthaceae), a common colonizer of disturbed habitats. In three populations monitored over 2 yr, most trees flowered in the order male ! female ! male, and resting periods between flowering bouts precluded selfing almost completely. Individuals flowered for several weeks, with the onset of flowering slightly asynchronous among trees. Pollination was by flies, and experimental pollen supplementation of a subset of a tree’s flowers did not increase fruit set, suggesting high levels of insect visitation and possible resource limitation. Nineteen percent of the 166 trees monitored skipped the first male phase, and another 13% skipped the female phase, remaining male in both years (and also a third year). The regular presence of pure males, if genetically fixed, would make B. tomentosa androdioecious in addition to duodichogamous. Comparison of duodichogamous taxa known so far shows that all have few ovules, fitting with the hypothesis that duodichogamy may result from male competition for access to a small supply of ovules. Cross-pollinating plants are under selection to synchronize pollen export and stigma receptivity among individuals. At the same time, individuals are under selection to separate pollen release and stigma receptivity to reduce stigma clogging, pollen discounting, and selfing (Lloyd and Webb, 1986). These two selective pressures have resulted in intricate temporal sexual patterns, namely, dichogamy, duodichogamy, and heterodichogamy. The most common of these is dichogamy, which involves male and female phases that may or may not be synchronized within and among individuals (Lloyd and Webb