Flash behavior of femalePhoturis versicolor fireflies (Coleoptera: Lampyridae) in simulated courtship and predatory dialogues

FemalePhoturis versicolor fireflies attempt to capture males by responding to heterospecific flash patterns. A mating-dependent switch occurs which affects response timing and frequency of female flashes. We examined the switch using females of known age, mating status, and flash experience to assess how accurate mimicry is, what factors influence it, and what mechanism produces it. Presentations of simulated male flash patterns before and after mating revealed elements of an entrainment mechanism controlling female responsiveness. Unmated females preferentially answered conspecific patterns with variable latencies, averaging 1 s. Mating induced changes in both response frequency and response latency: Females answered heterospecific patterns more frequently, and latencies elicited by conspecific patterns shifted away from the unmated range. Heterogeneity in mean and variance of response latency among individuals indicates that females do not share a discrete reply to a given pattern. Little correspondence exists between latencies of sympatric species andP. versicolor females, suggesting that the flash response mechanism produces entriainment to any rhythmic pattern, not a one-to-one matching between prey and predator latencies. Different selective scenarios underlie strict mimicry versus entrainment mimicry.     

Determination of the Luciferin Contents in Luminous and Non-Luminous Beetles

The contents of firefly luciferin in luminous and non-luminous beetles were determined by the methods of HPLC with fluorescence detection and the luminescence reaction of luciferin and firefly luciferase. Luminous cantharoids and elaterids contained various amounts of luciferin in the range of pmol to hundreds of nmol, but no luciferin was detected in the non-luminous cantharoids and elaterids.     

The evolutionary process of bioluminescence and aposematism in cantharoid beetles (Coleoptera: Elateroidea) inferred by the analysis of 18S ribosomal DNA

Cantharoid beetles are distinctive for their leathery soft elytra and conspicuous color or bioluminescence, and many of the members are equipped with chemical defenses. Thus, the vivid coloration of Cantharidae and Lycidae and the bioluminescence in Lampyridae and Phengodidae appear to be aposematic signals. However, the evolutionary aspect of their aposematism is not well understood, because the classification of the families remains controversial. In this study, we performed molecular phylogenetic analyses of species from cantharoid families, based on nucleotide sequence comparisons of nuclear 18S ribosomal DNA. The results shows that the luminous species Rhagophthalmus ohbai, which had sometimes been classified in Lampyridae, is excluded from a lampyrid clade and associates with the taxa of Phengodidae. The molecular data also suggests that four major subfamilies of Cantharidae (Cantharinae, Chauliognathinae, Malthininae, and Silinae) form a clade. The six subfamilies of Lampyridae are grouped and classified into two sublineages: Amydetinae + Lampyrinae + Photurinae and Cyphonocerinae + Luciolinae +Ototretinae. Genera Drilaster and Stenocladius are the members of Ototretinae in Lampyridae. These results conform to traditional taxonomy but disagree with more recent cladistic analyses. Based on these findings, we propose an evolutionary process of bioluminescence and aposematism in cantharoids: the clades of Cantharidae, Lampyridae, Lycidae, and Phengodidae have evolved aposematic coloration; subsequently Lampyridae and Phengodidae acquired bioluminescence; and these four major cantharoid families achieved their current adaptive diversities.     

Molecular phylogeny of Neotropical bioluminescent beetles (Coleoptera: Elateroidea) in southern and central Brazil

Bioluminescence in beetles is found mainly in the Elateroidea superfamily (Elateridae, Lampyridae and Phengodidae). The Neotropical region accounts for the richest diversity of bioluminescent species in the world with about 500 described species, most occurring in the Amazon, Atlantic rainforest and Cerrado (savanna) ecosystems in Brazil. The origin and evolution of bioluminescence, as well as the taxonomic status of several Neotropical taxa in these families remains unclear. In order to contribute to a better understanding of the phylogeny and evolution of bioluminescent Elateroidea we sequenced and analyzed sequences of mitochondrial NADH2 and the nuclear 28S genes and of the cloned luciferase sequences of Brazilian species belonging to the following genera: (Lampyridae) Macrolampis, Photuris, Amydetes, Bicellonycha, Aspisoma, Lucidota, Cratomorphus; (Elateridae) Conoderus, Pyrophorus, Hapsodrilus, Pyrearinus, Fulgeochlizus; and (Phengodidae) Pseudophengodes, Phrixothrix, Euryopa and Brasilocerus. Our study supports a closer phylogenetic relationship between Elateridae and Phengodidae as other molecular studies, in contrast with previous morphologic and molecular studies that clustered Lampyridae/Phengodidae. Molecular data also supported division of the Phengodinae subfamily into the tribes Phengodini and Mastinocerini. The position of the genus Amydetes supports the status of the Amydetinae as a subfamily. The genus Euryopa is included in the Mastinocerini tribe within the Phengodinae/Phengodidae. Copyright © 2013 John Wiley & Sons, Ltd.     

云南窗萤的形态学及其生物学特性（鞘翅目：萤科）

研究了云南窗萤卵到成虫不同发育阶段的形态学。根据野外观察和实验室饲养结果,记录了其生物学特性。卵、幼虫、蛹和雌成虫可发弱光,但雄成虫仅在受刺激时才发出更弱的光,云南窗萤可归属于昼行性萤火虫,而化学信号则是其雌雄在求偶时的主要识别方式。     

Aposematism and Bioluminescence: Experimental evidence from Glow-worm Larvae(Coleoptera: Lampyridae)

Bioluminescence most likely evolved under selection from the visually guided behaviours of co-occurring organisms, in particular that of predators. Many possible functions of light signals have been proposed and some are supported, but whatever their function may be, they make an easy target of the emitter unless it is defended. Therefore, we want to emphasise that in many cases bioluminescence can only have evolved through a defensive function. If this were the case, one would expect multimodal adaptiveness of luminescence with at least some evidence for a defensive function. Light signals could be used in many ways to reduce predation, but for spontaneous glowing species in particular, aposematism seems the only functional strategy. In a preliminary experiment with glowing and non-glowing dummy prey, we found that wild-caught toads discriminated against glowing prey. They showed significantly lower attack responses and higher latencies towards glowing prey dummies. However, some of the toads were less reluctant because they did not distinguish initially between prey with or without the light stimulus. Since the toads were collected in areas abundant with lampyrid glow-worms, which is the only luminous organism at this locality, and our results concur with the general evidence that they may have had previous experiences with this prey, we attribute the result to luminescent aposematism. From the literature, and from our own experiments, we know that toads and many other potential predators experience lampyrids as disagreeable prey. In future experiments we will test whether glow-worms are defended by luminescent aposematism or not. This revised version was published online in July 2006 with corrections to the Cover Date.