Chironomidae (Diptera) are among the most diverse and widespread aquatic insects, with roughly 5,500 described species. However, prior to the present work, no species of Chironomidae had been documented from the island of Hispaniola. Collections of non-biting midges, with emphasis on the lotic fauna, were made in the Dominican Republic during July of 2015. In total, 578 specimens belonging to 27 genera and at least 44 species within the subfamilies Chironominae (20 taxa), Orthocladiinae (16 taxa) and Tanypodinae (8 taxa) were found. The subfamilies Chironominae and Orthocladiinae predominated. Polypedilum was the most widespread and diverse genus of Chironominae. Metriocnemus were collected in bromeliad tanks. The chironomid fauna in Dominican Republic includes multiple genera with worldwide distributions, including Holarctic and Neotropical components.

Here we present a phylogeny of beetles (Insecta: Coleoptera) based on DNA sequence data from eight nuclear genes, including six single-copy nuclear protein-coding genes, for 367 species representing 172 of 183 extant families. Our results refine existing knowledge of relationships among major groups of bee- tles. Strepsiptera was confirmed as sister to Coleoptera and each of the suborders of Coleoptera was recovered as monophyletic. Interrelationships among the subor- ders, namely Polyphaga (Adephaga (Archostemata, Myxophaga)), in our study differ from previous studies. Adephaga comprised two clades corresponding to Hydrade- phaga and Geadephaga. The series and superfamilies of Polyphaga were mostly monophyletic. The traditional Cucujoidea were recovered in three distantly related clades. Lymexyloidea was recovered within Tenebrionoidea. Several of the series and superfamilies of Polyphaga received moderate to maximal clade support in most analyses, for example Buprestoidea, Chrysomeloidea, Coccinelloidea, Cucujiformia, Curculionoidea, Dascilloidea, Elateroidea, Histeroidea and Hydrophiloidea. However, 836 D. D. McKenna et al.
many of the relationships within Polyphaga lacked compatible resolution under maximum-likelihood and Bayesian inference, and/or lacked consistently strong nodal support. Overall, we recovered slightly younger estimated divergence times than pre- vious studies for most groups of beetles. The ordinal split between Coleoptera and Strepsiptera was estimated to have occurred in the Early Permian. Crown Coleoptera appeared in the Late Permian, and only one or two lineages survived the end-Permian mass extinction, with stem group representatives of all four suborders appearing by the end of the Triassic. The basal split in Polyphaga was estimated to have occurred in the Triassic, with the stem groups of most series and superfamilies originating during the Triassic or Jurassic. Most extant families of beetles were estimated to have Creta- ceous origins. Overall, Coleoptera experienced an increase in diversification rate com- pared to the rest of Neuropteroidea. Furthermore, 10 family-level clades, all in suborder Polyphaga, were identified as having experienced significant increases in diversification rate.These include most beetle species with phytophagous habits, but also several groups not typically or primarily associated with plants. Most of these groups originated in the Cretaceous, which is also when a majority of the most species-rich beetle families first appeared. An additional 12 clades showed evidence for significant decreases in diversi- fication rate. These clades are species-poor in theModern fauna, but collectively exhibit diverse trophic habits. The apparent success of beetles, as measured by species numbers, may result from their associations with widespread and diverse substrates – especially plants, but also including fungi, wood and leaf litter – but what facilitated these associ- ations in the first place or has allowed these associations to flourish likely varies within and between lineages.Our results provide a uniquelywell-resolved temporal and phylo- genetic framework for studying patterns of innovation and diversification in Coleoptera, and a foundation for further sampling and resolution of the beetle tree of life.

Stag beetles (family Lucanidae Latreille, 1804) are one of the earliest branching lineages of scarab beetles that are characterized by the striking development of the male mandibles. Despite stag beetles’ popularity among traditional taxonomists and amateur collectors, there has been almost no study of lucanid relationships and evolution. Entomologists, including Jeannel (1942), have long recognized resemblance between the austral stag beetles of the tribes Chiasognathini, Colophonini, Lamprimini, Pholidotini, Rhyssonotini, and Streptocerini, but this hypothesis of their close relationship across the continents has never been tested. To gain further insight into lucanid phylogeny and biogeography, we reconstructed the first molecular phylogeny of world stag beetles using DNA sequences from mitochondrial 16S rDNA, nuclear 18S and 28S rDNA, and the nuclear protein-coding (NPC) gene wingless for 93 lucanid species representing all extant subfamilies and 24 out of the 27 tribes, together with 14 representative samples of other early branching scarabaeoid families and two staphyliniform beetle families as outgroups. Both Bayesian inference (BI) and maximum likelihood inference (MLI) strongly supported the monophyly of Lucanidae sensu lato that includes Diphyllostomatidae. Within Lucanidae sensu stricto, the subfamilies Lucaninae and Lampriminae appeared monophyletic under both methods of phylogenetic inferences; however, Aesalinae and Syndesinae were found to be polyphyletic. A time-calibrated phylogeny based on five fossil data estimated the origin of crown group Lucanidae as circa 160 million years ago (MYA). Divergence between the Neotropical and Australasian groups of the Chiasognathini was estimated to be circa 47 MYA, with the South African Colophonini branching off from the ancient Chiasognathini lineage around 87 MYA. Another Gondwanan relationship was recovered between the Australasian Eucarteria and the Neotropical Casignetus, which diverged circa 58 MYA. Lastly, as Jeannel’s hypothesis predicted, divergence within Lampriminae between the Australasian Lamprima and the Neotropical Streptocerus was estimated to be circa 37 MYA. The split of these lineages were generally concordant with the pattern of continental break-up of the super-continent Gondwana, and our biogeographic reconstructions based on the dispersal-extinction-cladogenesis model (DEC) corroborate our view that the divergences in these austral lineages were caused by vicariance events following the Gondwanan break-up. In addition, the phylogenetic position and geographic origin of the Hawaiian genus Apterocyclus was revealed for the first time. Overall, our results provide the framework toward studying lucanid relationships and divergence time estimates, which allowed for more accurate biogeographic explanations and discussions on ancestral lucanids and the evolutionary origin of the enlarged male mandibles.