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Petrosaviales is an early diverging monocot order that includes only two genera with distinct nutritional modes, namely the autotrophic Japonolirion and mycoheterotrophic Petrosavia. A rare serpentine plant endemic to Japan, Japonolirionosense is the only species of this genus. Although Petrosavia species are known to produce seeds by autonomous self‐pollination, the mating system and flower visitors of J. osense remain unknown. In this study, the pollination biology of J. osense was investigated on a serpentine slope in northern Hokkaido, Japan. Pollination experiments suggested that J. osense predominantly depends on cross‐pollination by insect pollinators for seed production. Ants and dipterans were the main flower visitors to this species. This study showed that the two genera in Petrosaviales with distinct nutritional modes also have contrasting mating systems, which provides insights into the evolution of pollination biology in this early diverging monocot order. [ABSTRACT FROM AUTHOR]

Keywords: insect-pollination; Menispermaceae; Menispermum dauricum; nectar color; Ranunculales EN insect-pollination Menispermaceae Menispermum dauricum nectar color Ranunculales 1 4 4 03/06/23 20230301 NES 230301 Colored nectar is a rare phenomenon in angiosperms, occurring only in approximately 70 plant species that are largely vertebrate-pollinated and occur primarily on islands or mountains in tropical regions (Hansen et al., [5]). Thus, colored nectar could be undocumented in insect-pollinated flowers, especially species with small amounts of nectar. Ancestral reconstruction analysis of nectar color in Menispermaceae is needed to infer the evolutionary origin of the brown-colored nectar in I M i . In Tome, nectar sampling could not be done the day of flower sampling because nectar was sampled under a stereomicroscope, which was not available at the site. [Extracted from the article]

However, the flower visitors differed greatly between day and night; diurnal flower visitors were mainly bees (54.7%), hoverflies (9.0%), and butterflies (34.5%), whereas nocturnal flower visitors were exclusively moths (99.7%; Appendix S1: Table S6). If settling moths can recognize ambush predators on flowers, they should avoid the flowers with predators more frequently than those without predators. Although nocturnal insects such as moths are important pollinators of many flowering plants (Hahn and Brühl 2016), the impact of ambush predators on nocturnal pollinators remains unclear. Keywords: mantis; mantisfly; Mantodea; Neuroptera; pollinators; predation; Scutigeromorpha; settling moths EN mantis mantisfly Mantodea Neuroptera pollinators predation Scutigeromorpha settling moths 1 4 4 11/02/21 20211101 NES 211101 Ambush predators such as spiders affect the flower-visiting behavior of diurnal pollinators such as bees (Dukas 2001, Dukas and Morse 2003), potentially causing diurnal pollinators to avoid flowers where ambush predators wait (Dukas 2001). [Extracted from the article]

Generalized pollination systems may be favored in early spring flowering plants, as during this period pollinator activity is unpredictable. Many previous studies have concentrated on the importance of diurnal visitors in pollination, and consequently, information on the contribution of nocturnal visitors to pollination in early spring is limited. This study was conducted to evaluate the relative importance of diurnal and nocturnal pollinators in the early spring flowering dioecious shrub Stachyurus praecox (Stachyuraceae), in two temperate forests in central Japan. Visitors to the female and male flowers were observed during day and night, and their relative contributions to seed set were compared. The pollinator observations revealed that the diurnal and nocturnal insects visited both male and female flowers, and that the main flower visitors were diurnal small bees and flies as well as nocturnal settling moths. The diurnal and nocturnal flower visitors also acted as pollinators, as the pollen grains of S. praecox were attached to the insects collected from the female flowers. Pollination experiments demonstrated that the contributions of diurnal pollinators to the seed set were higher than those of the nocturnal pollinators. The results of this study indicate that S. praecox has a generalized pollination system, comprising both diurnal insects and nocturnal settling moths. Although the roles of diurnal insects are more important in the pollination of S. praecox, nocturnal settling moths may have a complementary role in early spring. [ABSTRACT FROM AUTHOR]

Premise of research. The majority of lepidopteran-pollinated flowers deposit pollen on the faces and proboscises of the pollinators. However, studies suggest that some flowers are sternotribically pollinated by settling moths. The present study focused on the pollination system and pollen placement pattern of Adenophora maximowicziana , which has pendant, bell-shaped flowers with exserted styles. Methodology. Diurnal and nocturnal flower visitors and their relative contributions to seed set of A. maximowicziana were compared in southwestern Japan. The pollen placement pattern of flower visitors, timing of anthesis, timing of sexual phase change, and diel pattern of nectar production were investigated to reveal floral adaptations to pollinators. Pivotal results. Pollination experiments and pollen load analysis indicated that nocturnal noctuid moths are the most important pollinators. Pollen placement on noctuid moths is highly precise. The majority of pollen grains are deposited onto the ventral side of the latter thorax and former abdomen. The flowers are adapted to nocturnal pollinators; anthesis, change to pistillate phase, and nectar production by flowers exclusively occur at night. Conclusions. This study confirms highly precise sternotribic pollination by settling moths in A. maximowicziana. Sternotribic pollination of A. maximowicziana by settling moths may be facilitated by the flowers' pendant corollas with exserted styles. [ABSTRACT FROM AUTHOR]

The pollination of summer-flowering plants by birds has rarely been reported in temperate Asia and Europe. However, we recorded the Japanese white-eyeZosterops japonicus(Passeriformes: Zosteropidae) visiting the flowers of the hemiparasitic plantTaxillus kaempferi(Loranthaceae) during mid-summer (July to August) in a temperate forest in central Japan. Field observations showed thatZ. japonicuswas an almost exclusive flower visitor ofT. kaempferi. Specifically,Z. japonicusinserted their bills frequently into the flower tubes ofT. kaempferi. The corollas ofT. kaempferiwere shorter thanZ. japonicusbills, suggesting thatZ. japonicusis able to obtain floral nectar fromT. kaempferi. Close-up pictures ofZ. japonicusvisiting flowers showed that the upper bill and facial feathers ofZ. japonicuscame into contact with the reproductive organs ofT. kaempferi, leading to the attachment of pollen to these body parts. Thus,Z. japonicusmight act as an important pollinator of the summer-flowering plantT. kaempferi.​ [ABSTRACT FROM AUTHOR]

Premise: Pollinators with flower constancy and long nectar‐feeding organs should favor less or no sexual dimorphism in the individual flowers of dioecious plants. This hypothesis is deduced because such pollinators can discriminate between intersexual flower size differences, and morphological differences between male and female flowers often diminish pollen transfer. Methods: We compared floral traits and pollinator behavior between male and female flowers in the hawkmoth‐pollinated species, Trichosanthes cucumeroides. In field studies, we removed petal fringes on both sexes and observed pollinators to assess the role of elaborate petal fringes in pollinator attraction and pollination success for each flower sex. Results: Female flowers had a similar front flower size and fringe extension as male flowers, supporting our hypothesis. In contrast, females allocated fewer resources to floral biomass. Additionally, they had smaller and narrower petal lobes, lower fringe density, shorter tubes with inferior nectar rewards, and lower display size than males, which is inconsistent with the hypothesis. Nocturnal hawkmoths prefer flowers with long fringe extensions. Fringe removal significantly decreased hawkmoth visitations to both female and male flowers but reduced success only in females. A literature survey indicated that female flowers of specialist‐pollinated species are similar in size or larger than the males and thus tend to attract more pollinators compared with female flowers of generalist‐pollinated species. Conclusions: Female flowers have evolved fringe extensions that are similar to those of male flowers, likely increasing pollinator attraction even slightly, and had less biomass in other floral parts and produced less nectar compared with male flowers. Our findings imply that female‐biased resource limitation and flower‐size sensitivity of pollinators together exert sex‐specific selection of floral traits in T. cucumeroides. [ABSTRACT FROM AUTHOR]