Evolution of host use in fungivorous ciid beetles (Coleoptera: Ciidae): Molecular phylogeny focusing on Japanese taxa

A new species of Cis Latreille (Coleoptera: Ciidae) widespread in Brazil but with similarities to the African fauna

Cis caramelo sp. nov. is described based on specimens collected in the North, Northeast, and Southeast Regions of Brazil. It stands out for being more similar to the species of Cis Latreille from Africa than South America. Cis caramelo sp. nov. fits into the Cis neserorum species-group, being morphologically similar to Cis aster Souza-Gonçalves & Lopes-Andrade, but differing in the presence of a sex patch on the first abdominal ventrite of males and in the morphology of the aedeagus, with a wide tegmen lacking acute tips on the sides and a penis wide and sclerotized at its basal portion, abruptly narrowed and membranous apically. Brief descriptions and images of immatures of C. caramelo sp. nov. are also provided.

Cis occamy sp. nov, the first representative of the Cis bilamellatus species-group (Coleoptera, Ciidae) in the Neotropical region

Cis occamy sp. nov. is described based on specimens collected at six localities within the Atlantic Forest of the South and Southeast Regions of Brazil. It is the first Neotropical species of the Cis bilamellatus species-group, an aggregate of Cis species in which males have a single plate on both the anterocephalic and anterior pronotal edges, females have a pronotum usually widest near the posterior edge and gradually narrowing anteriorly, and both sexes have dual elytral vestiture. Cis occamy sp. nov. is morphologically similar to the Australian Cis australis Blackburn and Cis walkeri Blair, but differs from both in the sparser pronotal punctation and vestiture, and in the males with anterocephalic edge broadly emarginate apically (barely emarginate in C. australis and not emarginate in C. walkeri) and the tegmen subparallel-sided for most of its length (conspicuously sinuous in C. australis and C. walkeri). Available data on host fungi and geographical distribution of the new species are also provided.

Omnivorous Notoxus trinotatus Pic (Coleoptera: Anthicidae) is a newly recognized vector of northern leaf blight in maize

The adaptations of omnivorous insects to food are manifested in a multifaceted manner, and the availability of food resources directly determines insect feeding tendencies, which contribute to a complex insect-food relationship and impact insect functionality in the environment. Stable isotope analysis was applied to test the feeding preference and further define the functional role of omnivorous beetles in cropland. Our results confirmed that as an omnivorous beetle, the fungivorous nature of Notoxus trinotatus accounted for a prominent proportion food selection at the adult stage, and more importantly, this dietary feature contributed to the dispersal of the northern corn leaf blight in maize (NLB) during the feeding trials. In addition to the preference for fungi, water supplementation was an essential element extending adult longevity, which directly prolonged the contact time of adults with pathogenic fungi in agricultural fields. Consistent with the herbivorous characteristics of beetles, before the emergence of NLB fungal pathogens, corn tissues served as the main food, which provided the beetles with more opportunities to transmit fungal pathogen propagules. We conclude that the role of N. trinotatus in carrying NLB pathogen is due to its feeding on this plant mycopathogen, and an increased abundance of beetles carrying the pathogen may increase the rate of NLB disease infestation. More focus should be concentrated on the functions of fungivorous beetles, not only as pathogen-transmitting pests, but also as an element among the balanced biotic factors in farmland.

Mitochondrial phylogenomics and mitogenome organization in the parasitoid wasp family Braconidae (Hymenoptera: Ichneumonoidea)

BACKGROUND

Mitochondrial (mt) nucleotide sequence data has been by far the most common tool employed to investigate evolutionary relationships. While often considered to be more useful for shallow evolutionary scales, mt genomes have been increasingly shown also to contain valuable phylogenetic information about deep relationships. Further, mt genome organization provides another important source of phylogenetic information and gene reorganizations which are known to be relatively frequent within the insect order Hymenoptera. Here we used a dense taxon sampling comprising 148 mt genomes (132 newly generated) collectively representing members of most of the currently recognised subfamilies of the parasitoid wasp family Braconidae, which is one of the largest radiations of hymenopterans. We employed this data to investigate the evolutionary relationships within the family and to assess the phylogenetic informativeness of previously known and newly discovered mt gene rearrangements.

RESULTS

Most subfamilial relationships and their composition obtained were similar to those recovered in a previous phylogenomic study, such as the restoration of Trachypetinae and the recognition of Apozyginae and Proteropinae as valid braconid subfamilies. We confirmed and detected phylogenetic signal in previously known as well as novel mt gene rearrangements, including mt rearrangements within the cyclostome subfamilies Doryctinae and Rogadinae.

CONCLUSIONS

Our results showed that both the mt genome DNA sequence data and gene organization contain valuable phylogenetic signal to elucidate the evolution within Braconidae at different taxonomic levels. This study serves as a basis for further investigation of mt gene rearrangements at different taxonomic scales within the family.

Global dispersal and diversification in ground beetles of the subfamily Carabinae

The origin and diversification process of lineages of organisms that are currently widely distributed among continents is an interesting subject for exploring the evolutionary history of global species diversity. Ground beetles of the subfamily Carabinae are flightless except for one lineage, but nevertheless occur on all continents except Antarctica. Here, we used sequence data from ultraconserved elements to reconstruct the phylogeny, divergence time, biogeographical history, ancestral state of hind wings and changes in the speciation rate of Carabinae. Our results show that Carabinae originated in the Americas and diversified into four tribes during the period from the late Jurassic to the late Cretaceous, with two in South America (Celoglossini) and Australasia (Pamborini) and two in Laurasia (Cychrini and Carabini). The ancestral Carabinae were inferred to be winged; three of four tribes (Cychrini, Ceglossini and Pamborini) have completely lost their hind wings and flight capability. The remaining tribe, Carabini, diverged into the subtribes Carabina (wingless) and Calosomina (winged) in the Oligocene. Carabina originated in Europe, spread over Eurasia and diversified into approximately 1000 species, accounting for around 60% of all Carabinae species. Calosomina that were flight-capable dispersed from North America or Eurasia to South America, Australia, and Africa, and then flightless lineages evolved on oceanic islands and continental highlands. The speciation rate increased in the Cychrini and Carabini clades in Eurasia. Within Carabini, the speciation rate was higher for wingless than winged states. Our study showed that the global distribution of Carabinae resulted from ancient dispersal before the breakup of Gondwana and more recent dispersal through flight around the world. These patterns consequently illustrate the causal relationships of geographical history, evolution of flightlessness, and the global distribution and species diversity of Carabinae.