ABSTRACT
We understand very little about the timing and origins of bioluminescence, particularly as a predator avoidance strategy. Understanding the timing of its origins, however, can help elucidate the evolution of this ecologically important signal. Using fireflies, a prevalent bioluminescent group where bioluminescence primarily functions as aposematic and sexual signals, we explore the origins of this signal in the context of their potential predators. Divergence time estimations were performed using genomic-scale datasets providing a robust estimate for the origin of firefly bioluminescence as both a terrestrial and as an aerial signal. Our results recover the origin of terrestrial beetle bioluminescence at 141.17 (122.63-161.17) Ma and firefly aerial bioluminescence at 133.18 (117.86-152.47) Ma using a large dataset focused on Lampyridae; and terrestrial bioluminescence at 148.03 (130.12-166.80) Ma, with the age of aerial bioluminescence at 104.97 (99.00-120.90) Ma using a complementary Elateroidea dataset. These ages pre-date the origins of all known extant aerial predators (i.e. bats and birds) and support much older terrestrial predators (assassin bugs, frogs, ground beetles, lizards, snakes, hunting spiders and harvestmen) as the drivers of terrestrial bioluminescence in beetles. These ages also support the hypothesis that sexual signalling was probably the original function of this signal in aerial fireflies.
Subject(s)
Chiroptera , Coleoptera , Animals , Fireflies , Genomics , PhylogenyABSTRACT
Oxygen is an important and often limiting reagent of a firefly's bioluminescent chemical reaction. Therefore, the development of the tracheal system and its subsequent modification to support the function of firefly light organs are key to understanding this process. We employ micro-CT scanning, 3D rendering, and confocal microscopy to assess the abdominal tracheal system in Photinus pyralis from the external spiracles to the light organ's internal tracheal brush, a feature named here for the first time. The abdominal spiracles in firefly larvae and pupae are of the biforous type, with a filter apparatus and appear to have an occlusor muscle to restrict airflow. The first abdominal spiracle in the adult firefly is enlarged and bears an occlusor muscle, and abdominal spiracles two through eight are small, with a small atrium and bilobed closing apparatus. Internal tracheal system features, including various branches, trunks, and viscerals, were homologized across life stages. In adults, the sexually dimorphic elaboration and increase in volume associated with tracheal features of luminous segments emphasizes the importance of gas exchange during the bioluminescent process.
Subject(s)
Coleoptera , Fireflies , Animals , Larva , Pupa , Trachea/diagnostic imagingABSTRACT
Petalacmis Olivier, 1908 is a poorly known genus of firefly endemic to South America and is currently the only member of the subfamily Lampyrinae, tribe Lampyrini known to occur on the continent. Here, we describe a new species, Petalacmistriplehorni sp. nov. from Bolivia and compare it to the two other described species in the genus. A key to Petalacmis species based on male traits, as well as illustrations of morphological features, are given in detail for the first time. We present unique, previously neglected traits of Petalacmis species and compare them to other Lampyrinae.
ABSTRACT
Anastrepha is the most diverse and economically important genus of Tephritidae in the American tropics and subtropics. The striking morphology of the third instars of Anastrephacaballeroi Norrbom, Anastrephacrebra Stone, Anastrephahaplacantha Norrbom & Korytkowski, Anastrephakorytkowskii Norrbom, Anastrephanolazcoae Norrbom & Korytkowski, and three newly discovered and as yet formally unnamed species (Anastrepha sp. Peru-82, Anastrephasp.nr.protuberans, and Anastrepha sp. Sur-16), and the more typical morphology of Anastrephaaphelocentema Stone, are described using light and scanning electron microscopy. To contribute to a better understanding of the interspecific and intraspecific variation among species in the mucronota species group and facilitate phylogenetic studies, we integrate molecular and morphological techniques to confirm the identity and describe third instars. Larva-adult associations and the identification of described larvae were confirmed using DNA barcodes. We provide diagnostic characters to distinguish larvae among these nine species of the mucronota group and separate them from those of the 29 other Anastrepha species previously described. We introduce the vertical comb-like processes on the oral margin as a novel character, and the unusual character states, including position and shape of the preoral lobe, and dentate or fringed posterior margins of the oral ridges and accessory plates. Our comparative morphology concurs with most previously inferred phylogenetic relationships within the mucronota group.
ABSTRACT
The West Indies represents one of the world's hotspots for beetles in the family Lampyridae and includes many endemic taxa. Nine out of 19 genera and 181 out of 186 species of the currently described firefly taxa present in the West Indies are endemic to the region. The objective of this catalog and bibliography is to generate an exhaustive list of firefly taxa present in the West Indies. A short discussion of previous efforts to catalog this fauna is presented, and all published distribution data is herein synthesized. This catalog serves as a starting point for systematic and taxonomic research on the fireflies of this region and provides a full bibliography for each species. The following species were deemed subspecific and unavailable: Callopisma rufa var. humeralis E. Olivier, Lucidota fulvotincta var. flavicollis Mutchler, and Robopus magnus var. turquino (Mutchler).
Subject(s)
Fireflies/classification , Animals , West IndiesABSTRACT
The speciose genus Cyclocephala Dejean (Coleoptera: Scarabaeidae: Dynastinae: Cyclocephalini) has attracted research attention due to their diversity, agroeconomic importance, and floral visitation habits. Uniquely among Cyclocephala species, C. mafaffa Burmeister and C. deceptor (Casey), two nearly identical species, are diagnosed by a pronotal character: beaded or not beaded basal pronotal margin. We evaluated these morphological species hypotheses with a phylogenetic analysis of 12S and COI, neighbor-joining analysis, and several single-locus species delimitation procedures (automatic barcode gap analysis and three Poisson tree processes analyses). Together, these analyses supported the species concepts for C. deceptor and C. mafaffa. Delimitation procedures supported several distinct molecular operational taxonomic units among these taxa. We consider the separation of C. deceptor and C. mafaffa to be valid. We conservatively synonymize the West Indian subspecies C. mafaffa grandis Burmeister under C. mafaffa and offer a discussion on subspecific concepts in Cyclocephalini. We designate the lectotype of Stigmalia deficiens Casey. Implications of this study for other geographically widespread cyclocephalines or species with variable pronotal morphology are discussed.
Subject(s)
Coleoptera , Animals , PhylogenyABSTRACT
Alecton discoidalis Laporte, 1833 is the most widespread species of the only firefly genus endemic to Cuba. It is commonly found in limestone landscapes across the western half of the country. Larvae of A. discoidalis were collected at Pan de Matanzas and reared through the adult stage under laboratory conditions. Larvae were fed mainly terrestrial snails from the families Potamiidae and Helicinidae. Alecton discoidalis underwent between four and eight larval instars. Females had more larval instars than males likely due to the need to gain more body mass for egg production. Eggs, larvae and pupae are described and illustrated, with emphasis on general body shape, as well as details of the larval head, antennae and mouthparts. Alecton discoidalis females are both brachypterous and physogastric.
Subject(s)
Coleoptera , Fireflies , Animals , Female , Larva , Male , PupaABSTRACT
The subfamily Erebinae (Lepidoptera, Erebidae) includes approximately 10,000 species with many still undescribed. It is one of the most diverse clades within the moth superfamily Noctuoidea and encompasses a diversity of ecological habits. Erebine caterpillars feed on a broad range of host plants including several economically important crops. Adults possess a unique array of adaptations for predator defense, including some of the most sensitive hearing organs (tympana) across the Lepidoptera and striking wing coloration to startle visual predators. Despite the relevance of these moths to agriculture and ecological research, a robust phylogenetic framework is lacking. Here we used anchored hybrid enrichment, a relatively new approach in phylogenomics, to resolve relationships among the subfamily. Using the recently developed Lep1 anchored hybrid enrichment probe set, 658 gene fragments with an average length of 320â¯bp were captured from an exemplar set of 75 erebine species, representing 73 genera and 23 tribes. While the total number of erebine tribes is not firmly established, this represents at least 75% of known tribal level diversity. Anchored hybrid enrichment data were partitioned by locus and by codon position for maximum likelihood phylogenetic analysis and coalescent-based species-tree approaches. Results from our study provided strong nodal support (BPâ¯≥â¯95) for nearly all nodes in the partitioned ML tree, solidifying many relationships that were previously uncertain or moderately supported based on morphology or a smaller number of gene fragments. Likelihood analyses confidently resolved the placement of Acantholipini as a sister tribe to Sypnini and all other Erebinae. The remaining tribes were placed in a single, strongly supported clade split into two major subclades. Additionally, 25 tropical species that did not have previous tribal assignments are confidently placed on the phylogeny. Statistical comparisons with Shimodaira-Hasegawa (SH) tests found that our maximum likelihood trees were significantly more likely than alternative hypotheses. This study demonstrates the utility of anchored phylogenomics for resolving relationships within subfamilies of Lepidoptera.
Subject(s)
Genomics , Hybridization, Genetic , Moths/genetics , Phylogeny , Animals , Base Sequence , Codon/genetics , Likelihood FunctionsABSTRACT
Many defended animals prevent attacks by displaying warning signals that are highly conspicuous to their predators. We hypothesized that bioluminescing fireflies, widely known for their vibrant courtship signals, also advertise their noxiousness to echolocating bats. To test this postulate, we pit naïve big brown bats (Eptesicus fuscus) against chemically defended fireflies (Photinus pyralis) to examine whether and how these beetles transmit salient warnings to bats. We demonstrate that these nocturnal predators learn to avoid noxious fireflies using either vision or echolocation and that bats learn faster when integrating information from both sensory streams-providing fundamental evidence that multisensory integration increases the efficacy of warning signals in a natural predator-prey system. Our findings add support for a warning signal origin of firefly bioluminescence and suggest that bat predation may have driven evolution of firefly bioluminescence.
Subject(s)
Animal Communication , Chiroptera/physiology , Echolocation/physiology , Fireflies/physiology , Predatory Behavior/physiology , Wings, Animal/physiology , Animals , MaleABSTRACT
The cyclocephaline scarabs (Scarabaeidae: Dynastinae: Cyclocephalini) are a speciose tribe of beetles that include species that are ecologically and economically important as pollinators and pests of agriculture and turf. We provide an overview and synopsis of the 14 genera of Cyclocephalini that includes information on: 1) the taxonomic and nomenclatural history of the group; 2) diagnosis and identification of immature life-stages; 3) economic importance in agroecosystems; 4) natural enemies of these beetles; 5) use as food by humans; 6) the importance of adults as pollination mutualists; 7) fossil cyclocephalines and the evolution of the group; 8) generic-level identification of adults. We provide an expanded identification key to genera of world Cyclocephalini and diagnoses for each genus. Character illustrations and generic-level distribution maps are provided along with discussions on the relationships of the tribe's genera.
ABSTRACT
Cyclocephaline scarab beetles represent the second largest tribe of the subfamily Dynastinae, and the group includes the most speciose genus of dynastines, Cyclocephala. The period following publication of Sebo Endrodi's The Dynastinae of the World has seen a huge increase in research interest on cyclocephalines, and much of this research has not been synthesized. The objective of this catalog and bibliography is to compile an exhaustive list of taxa in Cyclocephalini. This paper provides an updated foundation for understanding the taxonomy and classification of 14 genera and over 500 species in the tribe. It discusses the history of cataloging dynastine species, clarifies issues surrounding the neotype designations in Endrodi's revision of Cyclocephalini, synthesizes all published distribution data for cyclocephaline species, and increases accessibility to the voluminous literature on the group by providing an easily searchable bibliography for each species. We propose the nomen novum Cyclocephala rogerpauli, new replacement name, for C. nigra Dechambre.
ABSTRACT
The third instar and pupa of Phileurus truncatus (Palisot de Beauvois, 1806) (Coleoptera: Scarabaeidae: Dynastinae: Phileurini) is described for the first time based on specimens from Florida, United States of America. An identification key to the third instars of New World Phileurini is also provided.
Subject(s)
Coleoptera , Animals , Florida , Larva , PupaABSTRACT
Fireflies are some of the most captivating organisms on the planet. They have a rich history as subjects of scientific study, especially in relation to their bioluminescent behavior. Yet, the phylogenetic relationships of fireflies are still poorly understood. Here, we present the first total evidence approach to reconstruct lampyrid phylogeny using both a molecular matrix from six loci and an extensive morphological matrix. Using this phylogeny we test the hypothesis that adult bioluminescence evolved after the origin of the firefly clade. The ancestral state of adult bioluminescence is recovered as non-bioluminescent with one to six gains and five to ten subsequent losses. The monophyly of the family, as well as the subfamilies is also tested. Ototretinae, Cyphonocerinae, Luciolinae (incl. Pristolycus), Amydetinae, "cheguevarinae" sensu Jeng 2008, and Photurinae are highly supported as monophyletic. With the exception of four taxa, Lampyrinae is also recovered as monophyletic with high support. Based on phylogenetic and morphological data Lamprohiza, Phausis, and Lamprigera are transferred to Lampyridae incertae sedis.
Subject(s)
Fireflies/classification , Luminescence , Phylogeny , Animals , Bayes Theorem , Models, Theoretical , Sequence AlignmentABSTRACT
Light production by organisms, or bioluminescence, has fascinated not only scientists but also ordinary people all over the world, and it has been especially so in Japan. Here we review the biological information available to date for all luminous terrestrial animals known from Japan, particularly focusing on their diversity and systematics, their biology and ecology in Japan, and putative function and biochemistry of their luminescence. In total 58 luminous terrestrial animals have been described from Japan, which consist of 50 fireflies (Coleoptera: Lampyridae), one glowworm beetle (Coleoptera: Phengodidae), two fungus gnats (Diptera: Keroplatidae), one springtail (Collembola), one millipede (Diplopoda), one centipede (Chilopoda) and two earthworms (Oligochaeta). For all except some firefly species, the DNA "barcode" sequences of a cytochrome oxidase subunit I region are provided. We also introduce how intricately the seasonal appearance and glimmering of luminous insects, in particular those of fireflies, have been interwoven into the culture, art, literature and mentality of Japanese people.
Subject(s)
Arthropods/physiology , Luminescence , Oligochaeta/physiology , Animals , JapanABSTRACT
A second species of the enigmatic lampyrid genus Oculogryphus is described and figured as Oculogryphus bicolorsp. n. from Vietnam. The definition of the genus is slightly modified with consideration of newly detected morphological variation from this species. According to a comprehensive phylogenetic analysis including nearly 80% of documented lampyrid genera, Oculogryphus is the putative sister group to Stenocladius s. str. within the paraphyletic group of Ototretinae-Ototretadrilinae.The classification of Stenocladius is briefly discussed in this context.
ABSTRACT
A phylogenetic analysis of the tribe Liparocephalini Fenyes is presented based on morphological and molecular characters. The data set comprised 50 adult morphological characters, partial COI (907 bp), COII (366 bp) and 12S rDNA (325-355 bp), and nearly complete sequences of 18S rDNA (1768-1902 bp) for 21 species. Eighteen species of liparocephaline beetles from all eight genera and three outgroups, are included. The sequences were analysed separately and simultaneously with morphological characters by direct optimization in the program POY4 and by partitioned Bayesian analysis for the combined data. The direct optimization (DO) tree for the combined data under equal weighting, which also shows a minimum incongruence length difference value, resulted in a monophyletic Liparocephalini with the following patterns of phylogenetic relationships (outgroup ((Baeostethus, Ianmoorea) (Paramblopusa ((Amblopusa, Halorhadinus) (Liparocephalus, Diaulota))))). A sensitivity analysis using 16 different parameter sets for the combined data shows the monophyly of the liparocephalines and all its genera under all parameter sets. Bayesian analysis resulted in topological differences in comparison with the DO tree under equal weighting only in the position of the genus Paramblopusa and clade (Amblopusa + Halorhadinus), which were reversed. Historical biogeography and the stepwise evolutionary colonization of intertidal habitat in the Liparocephalini are discussed. Based on the biogeographical analyses, we hypothesize that the ancestor of the Liparocephalini occurred along the Panthallassan Ocean, the direct antecedent of the Pacific Ocean, followed by repeated dispersals to the Nearctic from the Palearctic. We also hypothesize that ancestors of the Liparocephalini appear to have arisen in the littoral zone of beaches and then colonized rocky reef areas in the low tidal zone later through high- to mid-tide zones. © The Willi Hennig Society 2009.
ABSTRACT
We undertook a comprehensive morphological and molecular phylogenetic analysis of dragonfly phylogeny, examining both extant and fossil lineages in simultaneous analyses. The legitimacy of higher-level family groups and the phylogenetic relationship between families were tested. Thirteen families were supported as monophyletic (Aeshnidae, Calopterygidae, Chlorocyphidae, Euphaeidae, Gomphidae, Isostictidae, Lestidae, Libellulidae, Petaluridae, Platystictidae, Polythoridae, Pseudostigmatidae and Synthemistidae) and eight as non-monophyletic (Amphipterygidae, Coenagrionidae, Corduliidae, Megapodagrionidae, Protoneuridae and Synlestidae), although Perilestidae and Platycnemididae were recovered as monophyletic under Bayesian analyses. Nine families were represented by one species, thus monophyly was not tested (Epiophlebiidae, Austropetaliidae, Chlorogomphidae, Cordulegastridae, Macromiidae, Chorismagrionidae, Diphlebiidae, Lestoideidae and Pseudolestidae). Epiprocta and Zygoptera were recovered as monophyletic. Ditaxinerua is supported as the sister lineage to Odonata, Epiophlebiidae and the lestid-like damselflies are sister to the Epiprocta and Zygoptera, respectively. Austropetaliidae + Aeshnidae is the sister lineage to the remaining Anisoptera. Tarsophlebia's placement as sister to Epiprocta or as sister to Epiprocta + Zygoptera was not resolved. Refinements are made to the current classification. Fossil taxa did not seem to provide signals crucial to recovering a robust phylogeny, but were critical to understanding the evolution of key morphological features associated with flight. Characters associated with wing structure were optimized revealing two wing character complexes: the pterostigma-nodal brace complex and the costal wing base & costal-ScP junction complex. In turn, these two complexes appear to be associated; the pterostigma-nodal brace complex allowing for further modification of the wing characters comprised within the costal wing base & costal-ScP junction complex leading the modern odonate wing. © The Willi Hennig Society 2008.
ABSTRACT
Through a phylogenetic analysis using adult morphological characters, we show that the origin of bioluminescence in cantharoid beetles appears to predate the origin of the family Lampyridae. The ability to produce and emit photic signals was first gained by larvae and appears to function as an aposematic warning display; it was subsequently gained in adults and is used as a sexual signal. Our analysis also suggests that while pheromonal sexual signals are used basally in the family, they are used in conjunction with and then subsequently replaced by photic signals in some lampyrid lineages. Both photic signals and the photic organs used to produce them have become greatly elaborated in the fireflies that no longer employ pheromonal sexual signals. In addition, the ability to produce a flashed sexual signal appears to have arisen at least three times in the family Lampyridae. Convergent evolution is also evident in a number of adult male photic organ morphologies. Further, we recommend that individual signal system components be compared rather than overall signal system complexity. The use of this strategy may allow one to recognize and better interpret adaptive correlations despite convergence or loss. We demonstrate that phylogenetic analysis is a powerful tool even for rapidly evolving traits.