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Johnson gives an overview of bird pollinators and the plant species they pollinate., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Sexual mimicry is a complex multimodal strategy used by some plants to lure insects to flowers for pollination. 1-4 It is notable for being highly species-specific and is typically mediated by volatiles belonging to a restricted set of chemical compound classes. 3 , 4 Well-documented cases involve exploitation of bees and wasps (Hymenoptera) 5 , 6 and flies (Diptera). 7-9 Although beetles (Coleoptera) are the largest insect order and are well known as pollinators of both early and modern plants, 10 , 11 it has been unclear whether they are sexually deceived by plants during flower visits. 12 , 13 Here we report the discovery of an unambiguous case of sexual deception of a beetle: male longhorn beetles (Chorothyse hessei, Cerambycidae) pollinate the elaborate insectiform flowers of a rare southern African orchid (Disa forficaria), while exhibiting copulatory behavior including biting the antennae-like petals, curving the abdomen into the hairy lip cleft, and ejaculating sperm. The beetles are strongly attracted by (16S,9Z)-16-ethyl hexadec-9-enolide, a novel macrolide that we isolated from the floral scent. Structure-activity studies 14 , 15 confirmed that chirality and other aspects of the structural geometry of the macrolide are critical for the attraction of the male beetles. These results demonstrate a new biological function for plant macrolides and confirm that beetles can be exploited through sexual deception to serve as pollinators., Competing Interests: Declaration of interests The authors declare no competing interests, (Copyright © 2021 Elsevier Inc. All rights reserved.)

During the evolutionary history of flowering plants, transitions between pollinator groups (pollinator shifts) have been frequent, 1 and contributed to the spectacular radiation of angiosperms. 2 Although the evolution of floral traits during pollinator shifts has been studied in real time under controlled laboratory conditions, 3 it is challenging to study in nature and therefore poorly understood. 4-7 Using a comparative, multidisciplinary approach, we dissect the evolution of floral traits during a pollinator shift in the long-spurred African orchid Satyrium longicauda. Phylogenetic analysis and ecological experiments revealed a shift from moth- to oil-collecting bee pollination. Remarkably, flowers of the bee-pollinated form are similar in morphology, color, and overall volatile chemistry to those of moth-pollinated forms, but differ in having spurs that are mostly devoid of nectar, and have an elevated presence of the oil-derived compound diacetin, which oil-collecting bees use as a cue for oil presence. 8 Experiments demonstrated that long spurs are critical for pollination of a moth-pollinated form, but are not needed for pollination of the bee-pollinated form. We conclude that the pollinator shift in Satyrium was mediated by a switch in chemistry of the pollinator reward. The ancestral presence of diacetin might have served as a pre-adaptation for bee pollination, whereas the current mismatch between flower morphology and bees is due to the retention of vestigial floral spurs. These results elucidate the sequence of floral evolution in the early stages of pollinator shifts and help to explain the assembly of suites of co-varying traits through pre-adaptation and vestigialization. 9-12 ., Competing Interests: Declaration of Interests The authors declare no competing interests., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Four to six percent of plants, distributed over different angiosperm families, entice pollinators by deception [1]. In these systems, chemical mimicry is often used as an efficient way to exploit the olfactory preferences of animals for the purpose of attracting them as pollinators [2,3]. Here, we report a very specific type of chemical mimicry of a food source. Ceropegia sandersonii (Apocynaceae), a deceptive South African plant with pitfall flowers, mimics attacked honeybees. We identified kleptoparasitic Desmometopa flies (Milichiidae) as the main pollinators of C. sandersonii. These flies are well known to feed on honeybees that are eaten by spiders, which we thus predicted as the model chemically mimicked by the plant. Indeed, we found that the floral scent of C. sandersonii is comparable to volatiles released from honeybees when under simulated attack. Moreover, many of these shared compounds elicited physiological responses in antennae of pollinating Desmometopa flies. A mixture of four compounds-geraniol, 2-heptanone, 2-nonanol, and (E)-2-octen-1-yl acetate-was highly attractive to the flies. We conclude that C. sandersonii is specialized on kleptoparasitic fly pollinators by deploying volatiles linked to the flies' food source, i.e., attacked and/or freshly killed honeybees. The blend of compounds emitted by C. sandersonii is unusual among flowering plants and lures kleptoparasitic flies into the trap flowers. This study describes a new example of how a plant can achieve pollination through chemical mimicry of the food sources of adult carnivorous animals., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

In this Quick Guide, Johnson introduces the reader to carrion flowers, which evolved to mimic rotting flesh. This adaptation attracts insects that facilitate pollination., (Copyright © 2016 Elsevier Ltd. All rights reserved.)