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Visual signals in animals are often shaped by sexual selection. For aposematic species, advantages may result from advertising unpalatability to decrease predation and attracting mates to increase reproductive success. On Green Island, Taiwan, most Eupyrgops waltonianus weevils have metallic blue spots on the body; however, some weevils have no conspicuous coloration. The role of coloration in sexual selection and any disadvantages encountered by dull individuals are unknown. To understand whether morphological traits affect mating success in E. waltonianus , we compared different traits between mating and nonmating individuals in the field. A manipulation experiment was also used to test whether coloration affects mating choice and behaviour. The function of colour as an aposematic signal was tested. Results showed that body size and coloration were important indicators of female mating success in field and laboratory experiments, respectively. In the field, males preferred to mate with larger, more conspicuous females, and females preferred to mate with conspicuous males; however, no such preference was shown in the laboratory. Intrasexual competition was stronger in males than in females. Predators avoided colourful weevils. Thus, conspicuous coloration in both sexes is a multifunctional trait and could be an attractive or aposematic signal for different receivers. • The spots on weevils play an important role in survival and reproduction. • Higher spot area ratio was related to a higher mating probability in the field. • Weevils displayed higher levels of male-male than female-female competition. • Weevils' coloration could be attractive or aposematic depending on receiver type. [ABSTRACT FROM AUTHOR]

[Display omitted] • Disjunct distribution of the Limenitidinae butterflies between Asia and other continents are the outcomes of multiple intercontinental dispersals after the Eocene. • The Adelpha alala -species group should be transferred to the genus Limenitis. • Museum specimens are excellent sources for molecular phylogenetics and biogeography with the aid of next-generation sequencing. Most members of the nymphalid subfamily Limenitidinae are distributed in tropical regions of Africa, Asia, and the Americas. Previous studies have inferred their higher-level phylogeny and found that Southeast Asia seems to be the center of origin, with numerous dispersal events to other continents. However, the complete biogeographic history of Limenitidinae butterflies is still largely unknown. We sampled 181 taxa from 164 species and used a metagenomic method to obtain 40 genes (mitogenomes and three nuclear ribosomal loci) for inferring the historical biogeography of the group. We find that Limenitidinae originated in eastern Asia during the early Eocene (ca. 52 Ma) and started to diversify and disperse into Africa before the end of Eocene. Intercontinental exchanges between Africa and eastern Asia continued in the early Miocene: Asian Adoliadini and Asian endemic taxa Bhagadatta had African origins in the Oligocene, whereas African Neptini dispersed in the opposite direction from Asia in the early Miocene. In addition, ancestors of the tribes Limenitidini and Adoliadini dispersed into the Neotropics and Australasia multiple times during the early-to-middle Miocene. Eastern Asia is the center of origin of the tribe Limenitidini, with several taxa disjunctly distributed in eastern Asia and the Americas. Our work provides a robust phylogenetic hypothesis of relationships in the tribe Limenitidini and suggests that the alala- species group of Adelpha should be placed in the genus Limenitis. Renamed taxa comb. nov. based on our findings are listed in the text. [ABSTRACT FROM AUTHOR]

Toxic or noxious prey often signal their unpalatability through aposematic coloration, and the evolution of aposematism has become a model system in evolutionary behaviour. Aposematic colours are not only easily recognized by predators, but, for many predators, aposematism enhances learning and memory retention. In this study, we used a visually oriented, insectivorous agamid lizard, Diploderma swinhonis , to test whether aposematic coloration enhances lizards' ability to detect and remember distasteful prey. We exposed lizards to quinine-flavoured crickets, Gryllus bimaculatus , that were dyed with colours generally regarded as aposematic (red) and nonaposematic (green). After a single exposure, lizards readily learned to reject both red and green crickets, but in subsequent trials they were more hesitant to attack red than green ones. However, the lizards remembered both types of prey for up to 60 days and showed a similarly high rate of generalizing that aversion from coloured to noncoloured crickets. Our results demonstrate that visually hunting lizards exhibit nuanced patterns of learning and memory in foraging tasks and make ideal subjects for experimental work on aposematism. • We offered different colours of dyed crickets to insectivorous lizards. • Lizards attacked red crickets less often than green or black ones. • We then trained new lizards to avoid dyed crickets by adding a distasteful powder. • Lizards learned after a single exposure not to attack crickets, regardless of colour. • Lizards remembered red crickets better than green crickets up to 60 days. [ABSTRACT FROM AUTHOR]