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The bethylid genus Sierola is large and widespread, but largely undescribed. Two new species are described from New Zealand, the endemic Sierola houdiniae sp. nov. and presumed adventive S....

Threats to endangered insect species that act independently of those associated with habitat loss are often suspected, but are rarely confirmed or quantified. This may hinder the development of the most effective recovery strategies, which are increasingly needed for listed insects. Since 2006, 14 species of flies within the large, showy Hawaiian picture-winged Drosophila group have been added to the US threatened and endangered species list. Many of these species are thought to be limited by host plant rarity, but also by predation on immature stages by invasive ants. We tested the latter hypothesis with a field experiment involving Drosophila crucigera, a more common surrogate for sympatric endangered species, and the invasive ant Solenopsis papuana, on the island of Oʻahu. We established ant suppression and control plots across three forest sites. Within each plot we placed a host plant branch piece, into which lab-reared flies had oviposited, and subsequently tracked weekly emergence of adults. Numbers of flies that emerged were 2.4 times higher in ant-suppressed plots than in control plots; this 58% reduction in survival from egg to adult in the presence of ants was similar across all three sites. Among plots, numbers of emerged flies exhibited a pattern suggesting that the detrimental effect of ants is density dependent. These results confirm that S. papuana, and possibly other invasive ant species, can strongly impact the reproductive success of Hawaiian picture-winged Drosophila. They also point to several management actions, beyond habitat restoration, that may improve the recovery of these imperiled flies.

Summary Lifetime reproductive capacity is a critical fitness component. In insects, female reproductive capacity is largely determined by the number of ovarioles, the egg-producing subunits of the ovary [e.g., 1 ]. Recent work has provided insights into ovariole number regulation in Drosophila melanogaster. However, whether mechanisms discovered under laboratory conditions explain evolutionary variation in natural populations is an outstanding question. We investigated potential effects of ecology on the developmental processes underlying ovariole number evolution among Hawaiian Drosophila, a large adaptive radiation wherein the highest and lowest ovariole numbers of the family have evolved within 25 million years. Previous studies proposed that ovariole number correlated with oviposition substrate [ 2 , 3 , 4 ] but sampled largely one clade of these flies and were limited by a provisional phylogeny and the available comparative methods. We test this hypothesis by applying phylogenetic modeling to an expanded sampling of ovariole numbers and substrate types and show support for these predictions across all major groups of Hawaiian Drosophila, wherein ovariole number variation is best explained by adaptation to specific substrates. Furthermore, we show that oviposition substrate evolution is linked to changes in the allometric relationship between body size and ovariole number. Finally, we provide evidence that the major changes in ovarian cell number that regulate D. melanogaster ovariole number also regulate ovariole number in Hawaiian drosophilids. Thus, we provide evidence that this remarkable adaptive radiation is linked to evolutionary changes in a key reproductive trait regulated at least partly by variation in the same developmental parameters that operate in the model species D. melanogaster.

Lifetime reproductive capacity, or the total number of offspring that an individual can give rise to in its lifetime, is a fitness component critical to the evolutionary process. In insects, female reproductive capacity is largely determined by the number of ovarioles, the egg-producing subunits of the ovary. Recent work has provided insights into the genetic and environmental control of ovariole number inDrosophila melanogaster. However, whether regulatory mechanisms discovered under laboratory conditions also explain evolutionary variation in natural populations is an outstanding question. Here we report, for the first time, insights into the mechanisms regulating ovariole number and its evolution among Hawai’ianDrosophila, a large adaptive radiation of fruit flies in which the highest and lowest ovariole numbers of the genus have evolved within 25 million years. Using phylogenetic comparative methods, we show that ovariole number variation among Hawai’ianDrosophilais best explained by adaptation to specific oviposition substrates. Further, we show that evolution of oviposition on ephemeral egg-laying substrates is linked to changes the allometric relationship between body size and ovariole number. Finally, we provide evidence that the developmental mechanism principally responsible for controlling ovariole number inD. melanogasteralso regulates ovariole number in natural populations of Hawai’ian drosophilids. By integrating ecology, organismal growth, and cell behavior during development to understand the evolution of ovariole number, this work connects the ultimate and proximate mechanisms of evolutionary change in reproductive capacity.

The Hawaiian picture wing Drosophila are a striking example of adaptive radiation in specialist saprophages on an island system. We use DNA sequences from five nuclear genes with a total of 4260 nucleotides to provide a comprehensive phylogeny and biogeographic analysis of 90 species in the Hawaiian Drosophila picture wing clade. The current analysis indicates that the evolution of the picture wing clade took place more recently than previously suggested. The relationships of several morphologically anomalous taxa are resolved with strong support. Biogeography and host plant analyses show two periods of rapid divergence occurred when Kauai and Oahu were the main high islands, indicating that a combination of complex topographical features of islands and development of novel host plant associations was key to the rapid diversification of these lineages. For the past 2 million years, host associations within lineages have been largely stable, and speciation has occurred primarily due to the establishment of populations on newer islands as they arose followed by divergence by isolation. The existence of several apparently relictual taxa suggests that extinction has also played a major role in assembly of the present Hawaiian Drosophila fauna.

Due to habitat loss, disease, and introduction of nonnative species, many native species in Hawai‘i have gone extinct or are at risk of extinction. As a result of interspecific interactions such as pollination, the decline, loss, or introduction of species can have cascading effects on island ecosystems. We studied Hylaeus spp., Hawai‘i's yellow-faced bees, the only native bees in Hawai‘i. This group of potentially important pollinators has been largely overlooked until recently, and its conservation status and ecological role are virtually unknown. We investigated how native (Hylaeus spp.) and nonnative (Apis mellifera) bees interact with flowering plants in a large-scale pasture-to-forest restoration system. We used pan traps and nets to collect bees in mature forest, remnant corridors, planted Acacia koa tracts, and open pastureland. We removed pollen from each specimen and identified it using pollen samples collected on-site. We found that Hylaeus spp. were more likely to carry less pollen a...

Insects associate with a diversity of microbes that can shape host ecology and diversity by providing essential biological and adaptive services. For most insect groups, the evolutionary implications of host–microbe interactions remain poorly understood. Geographically discrete areas with high biodiversity offer powerful, simplified model systems to better understand insect–microbe interactions. Hawaii boasts a diverse endemic insect fauna (~6000 species) characterized by spectacular adaptive radiations. Despite this, little is known about the role of bacteria in shaping this diversity. To address this knowledge gap, we inaugurate the Native Hawaiian Insect Microbiome Initiative (NHIMI). The NHIMI is an effort intended to develop a framework for informing evolutionary and biological studies in Hawaii. To initiate this effort, we have sequenced the bacterial microbiomes of thirteen species representing iconic, endemic Hawaiian insect groups. Our results show that native Hawaiian insects associate with a diversity of bacteria that exhibit a wide phylogenetic breadth. Several groups show predictable associations with obligate microbes that permit diet specialization. Others exhibit unique ecological transitions that are correlated with shifts in their microbiomes (e.g., transition to carrion feeding from plant-feeding in Nysius wekiuicola). Finally, some groups, such as the Hawaiian Drosophila, have relatively diverse microbiomes with a conserved core of bacterial taxa across multiple species and islands.

The Island of Hawai'i is a dynamic assemblage of five volcanoes with wet forest habitat currently existing in four distinct natural regions that vary in area, age and geographical isolation. In this complex landscape, alternative assumptions of the relative importance of specific habitat characteristics on evolutionary and ecological processes predict strikingly different general patterns of local diversity and regional similarity. In this study, we compare alternative a priori hypotheses against observed patterns within two distinct biological systems and scales: community composition of wet forest vascular plant species and mitochondrial and nuclear genes of Drosophila sproati, a wet-forest-restricted endemic. All observed patterns display strong and similar regional structuring, with the greatest local diversity found in Kohala and the windward side of Mauna Loa, the least in Ka'ū and Kona, and a distinctive pattern of regional similarity that probably reflects the historical development of this habitat on the island. These observations largely corroborate a biogeographical model that integrates multiple lines of evidence, including climatic reconstruction, over those relying on single measures, such as current habitat configuration or substrate age. This method of testing alternative hypotheses across biological systems and scales is an innovative approach for understanding complex landscapes and should prove valuable in diverse biogeographical systems.

The spoon tarsus species subgroup is revised and this clade is placed in the modified tarsus group of Hawaiian Drosophila. The species boundaries in this group are discussed in light of diagnostic secondary sexual characters of males. Drosophila septuosa Hardy is regarded as a junior synonym of Drosophila percnosoma Hardy. A new species, Drosophila kikalaeleele Lapoint, Magnacca & O’Grady is described. Drosophila fastigata Hardy, a species endemic to O‘ahu, is added to the species subgroup, bringing the total number of known species to 12. An updated key to species is provided to the spoon tarsus subgroup.

The present paper transfers eight species from the genus Drosophila to the genus Scaptomyza based on characteristics of the male genitalia. One species, Scaptomyza (Titanochaeta) canuta (Hardy) new combination, fits within the concept of the subgenus Titanochaeta. The remaining seven taxa, S. improcera (Hardy) new combination, S. magnipalpa (Hardy) new combination, S. parva (Grimshawi) new combination, S. prolixa (Hardy) new combination, S. taractica (Hardy) new combination, S. totonigra (Hardy) new combination, and S. vinnula (Hardy) new combination, are included as unplaced species of Scaptomyza An additional species, Scaptomyza (Grimshawomyia) undulata (Grimshaw) new com- bination, is transferred from the subgenus Engiscaptomyza to Grimshawomyia based on morphological and molecular characters. An expanded key to the subgenera of Scaptomyza that includes these unplaced taxa is presented. In addition, Drosophila attigua Hardy & Kaneshiro is reduced to a junior new synonym of D. sharpi Grimshaw.

The 'nudidrosophila' and 'ateledrosophila' species groups, formerly described as genera, are a relatively small and understudied part of the enormous Hawaiian Drosophila radiation. Only nine species were described previously. Here we revise the two groups, provide a key to males and females, and describe fully all species. The 'ateledrosophila' group now contains three species, D. diamphidia Hardy, D. papala sp.n. ,a ndD. preapicula Hardy. The 28 species of the 'nudidro- sophila' group are separated into five subgroups: 'hirtitibia' (D. hirtitibia Hardy, D. konaensis sp.n., D. mawaena sp.n. ,a ndD. papaalai sp.n.); 'kahania' (D. kahania sp.n.

The 60 species of native Hylaeus bees in the Hawaiian Islands are important pollinators in native ecosystems, but they have been almost completely ignored in conservation studies. The only previous assessment of the conservation status of the individual species was not based on recent collections. Here I report on conservation status of all known species, based on collections made from 1999 to 2002. Species are arranged into six categories according to degree of threat, and species considered to be threatened are discussed individually. Five species have not been collected recently from one or more islands from which they are historically known, seven are restricted to endangered habitat, 10 are considered to be very rare and potentially endangered, and 10 have not been collected recently and could be extinct. With such a high proportion of rare species and the importance of Hylaeus species as pollinators, further work on their ecology is needed.

The only bees native to the Hawaiian Islands form a single clade of 60 species in the genus Hylaeus. The group is understudied and relatively poorly known. A data set consisting of 1201 base pairs of the mitochondrial genes cytochrome oxidase I and II and tRNALeucine, and 14 morphological characters was used to construct a phylogenetic tree for 48 of the 60 known species. Genetic variation was high, including amino acid changes, and a number of species showed evidence of heteroplasmy. Tree support was low due to high levels of homoplasy. Biogeographical analysis using DIVA indicates that early radiation took place on the island of Hawaii. This places an upper age limit of only 0.4–0.7 Myr for the group, an unusually short time for such a large radiation. Moreover, it is an unusual biogeographical pattern among the Hawaiian biota. � The Willi Hennig Society 2006.

The Hawaiian Drosophilidae radiation is an ecologically and morphologically diverse clade of almost 700 described species. A phylogenetic approach is key to understanding the evolutionary forces that have given rise to this diverse lineage. Here we infer the phylogeny for the antopocerus, modified tarsus and ciliated tarsus (AMC) clade, a lineage comprising 16% (91 of 687 species) of the described Hawaiian Drosophilidae. To improve on previous analyses we constructed the largest dataset to date for the AMC, including a matrix of 15 genes for 68 species. Results strongly support most of the morphologically defined species groups as monophyletic. We explore the correlation of increased diversity in biogeography, sexual selection and ecology on the present day diversity seen in this lineage using a combination of dating methods, rearing records, and distributional data. Molecular dating analyses indicate that AMC lineage started diversifying about 4.4 million years ago, culminating in the present day AMC diversity. We do not find evidence that ecological speciation or sexual selection played a part in generating this diversity, but given the limited number of described larval substrates and secondary sexual characters analyzed we can not rule these factors out entirely. An increased rate of diversification in the AMC is found to overlap with the emergence of multiple islands in the current chain of high islands, specifically Oahu and Kauai.

As the globally dominant group of pollinators, bees provide a key ecosystem service for natural and agricultural landscapes. Their corresponding global decline thus poses an important threat to plant populations and the ecosystems they support. Bee conservation requires rapid and effective tools to identify and delineate species. Here, we apply DNA barcoding to Irish solitary bees as the first step towards a DNA barcode library for European solitary bees. Using the standard barcoding sequence, we were able to identify 51 of 55 species. Potential problems included a suite of species in the genus Andrena, which were recalcitrant to sequencing, mitochondrial heteroplasmy and parasitic flies, which led to the production of erroneous sequences from DNA extracts. DNA barcoding enabled the assignment of morphologically unidentifiable females of the parasitic genus Sphecodes to their nominal taxa. It also enabled correction of the Irish bee list for morphologically inaccurately identified specimens. However, the standard COI barcode was unable to differentiate the recently diverged taxa Sphecodes ferruginatus and S. hyalinatus. Overall, our results show that DNA barcoding provides an excellent identification tool for Irish solitary bees and should be rolled out to provide a database for solitary bees globally.

The issue of mitochondrial heteroplasmy has been cited as a theoretical problem for DNA barcoding but is only beginning to be examined in natural systems. We sequenced multiple DNA extractions from 20 individuals of four Hawaiian Hylaeus bee species known to be heteroplasmic. All species showed strong differences at polymorphic sites between abdominal and muscle tissue in most individuals, and only two individuals had no obvious segregation. Two specimens produced completely clean sequences from abdominal DNA. The fact that these differences are clearly visible by direct sequencing indicates that substantial intra-individual mtDNA diversity may be overlooked when DNA is taken from small tissue fragments. At the same time, differences in haplotype distribution among individuals may result in incorrect recognition of cryptic species. Because DNA barcoding studies typically use only a small fragment of an organism, they are particularly vulnerable to sequencing bias where heteroplasmy and haplotype segregation are present. It is important to anticipate this possibility prior to undertaking large-scale barcoding projects to reduce the likelihood of haplotype segregation confounding the results.

The Hawaiian Drosophilidae is one of the best examples of rapid speciation in nature. Nearly 1,000 species of endemic drosophilids have evolved in situ in Hawaii since a single colonist arrived over 25 million years ago. A number of mechanisms, including ecological adaptation, sexual selection, and geographic isolation, have been proposed to explain the evolution of this hyperdiverse group of species. Here, we examine the known ecological associations of 326 species of endemic Hawaiian Drosophilidae in light of the phylogenetic relationships of these species. Our analysis suggests that the long-accepted belief of strict ecological specialization in this group does not hold for all taxa. While many species have a primary host plant family, females will also oviposit on non-preferred host plant taxa. Host shifting is fairly common in some groups, especially the grimshawi and modified mouthparts species groups of Drosophila, and the Scaptomyza subgenus Elmomyza. Associations with types of substrates (bark, leaves, flowers) are more evolutionarily conserved than associations with host plant families. These data not only give us insight into the role ecology has played in the evolution of this large group, but can help in making decisions about the management of rare and endangered host plants and the insects that rely upon them for survival.

Previous phylogenetic work on the Hawaiian bees of the genus Hylaeus, based on mitochondrial DNA and morphology, appeared to support a recent origin for the group, but support for the resulting tree was weak. Four nuclear genes with varying evolutionary rates -- arginine kinase, EF-1alpha, opsin, and wingless -- were sequenced for a reduced taxon set in an attempt to find one or more data set that would provide better support. All showed very low variation (2%) in the ingroup. Comparison among genes revealed a much higher than expected rate of evolution in mtDNA, especially at first and second positions. While the data from the nuclear genes showed insufficient variation for phylogenetic analysis, the strong sequence similarity among the Hawaiian species supports the previous hypothesis of a recent origin for the group.

New island records are reported for five species of Asteia endemic to the Hawaiian Islands (A. hawaiiensis, A. mauiensis, A. molokaiensis, A. palikuensis, A. sabroskyi). These new records expand our understanding of distributions in Asteia, change the percentage of single island endemics from 78% to 33%, and have significance in how we view the process of diversification acting in this lineage. We also present a list of the known rearing records for two species in this group. Asteia montgomeryi has been recorded from Erythrina and A. sabroskyi has been reared from Pisonia, Urera, Charpentiera and Hibiscadelphus.

The picture wing species group of Hawaiian Drosophila is the only one to be relatively well known taxonomically, butspecies continue to be discovered. Here seven new species are described: Drosophila kikiko new species, Drosophila ki- noole new species, Drosophila moli new species, Drosophila nukea new species, Drosophila opuhe new species, Dros- ophila pihulu new species, and Drosophila pilipa new species. In addition, the male of Drosophila oreas Hardy isdescribed for the first time, and Drosophila virgulata Hardy & Kaneshiro is reduced to a new junior synonym of Dros- ophila lanaiensis Grimshaw, and the status of the latter and Drosophila ciliaticrus Hardy is clarified. A complete key to all the picture wing species is provided.

New insect species, even in relatively conspicuous taxa, continue to be discovered on O‘ahu despite its status as the most intensively collected island in Hawai‘i. This paper describes two new island endemic bees, Hylaeus makaha new species and Hylaeus ulaula new species. Both are known from a single site, a patch of remnant diverse mesic forest in Makaha Valley.