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Sesiids are a diverse group of predominantly diurnal moths, many of which are Batesian mimics of Hymenoptera. However, their diversity and relationships are poorly understood. A multi-gene phylogenetic analysis of 48 North American sesiid species confirmed the traditional taxonomic tribal ranks, demonstrated the paraphyly of Carmenta and Synanthedon with respect to several other genera and ultimately provided minimal phylogenetic resolution within and between North American and European groups. Character support from each gene suggested inconsistency between the phylogenetic signal of the CAD gene and that of the other four genes. However, removal of CAD from subsequent phylogenetic analyses did not substantially change the initial phylogenetic results or return Carmenta and Synanthedon as reciprocally monophyletic, suggesting that it was not impacting the overall phylogenetic signal. The lack of resolution using genes that are typically informative at the species level for other lepidopterans suggests a surprisingly rapid radiation of species in Carmenta/Synanthedon. This group also exhibits a wide range of mimicry strategies and hostplant usage, which could be fertile ground for future study.

Although there is scientific consensus on most of the major biogeographic regions in the world, the demarcation of the area connecting Southeast Asia with Australia and Oceania remains debated. Two candidate boundaries potentially explain faunistic diversity patterns in the regions: Lydekker’s and Wallace’s lines. The islands in between both ‘lines’ are jointly termed Wallacea, with Sulawesi as the largest landmass. We surveyed Dacini fruit flies (Tephritidae: Dacinae) in Sulawesi between 2016 and 2019 using traps baited with male lures, resulting in 4,517 collected flies. We identified all specimens to species level, which adds 15 new species records to the island, bringing the total number of Dacini species in Sulawesi to 83. The biogeographic affinity of species in the updated checklist reveals a strong connection with former ‘Sunda’ (41% of species); validating Lydekker’s line, but also a high level of endemism (47% of species), confirming the uniqueness of Wallacea as a biogeographic region. We further describe a new species, Bactrocera (Bactrocera) niogreta Doorenweerd, sp. nov. and discuss the taxonomy of several interesting species.

Understanding the factors that determine the realized and potential distribution of a species requires knowledge of abiotic, physiological, limitations as well as ecological interactions. Fungi of the order Laboulbeniales specialize on arthropods and are typically thought to be highly specialized on a single species or closely related group of species. Because infections are almost exclusively transmitted through direct contact between the hosts, the host ecology, to a large extent, determines the distribution and occurrence of the fungus. We examined ~20,000 fruit flies (Diptera: Dacinae) collected in Malaysia, Sulawesi, Australia, and the Solomon Islands between 2017 and 2019 for fungal infections and found 197 infected flies across eight different Bactrocera species. Morphology and 1,363 bps of small subunit (18S) DNA sequences both support that the infections are from a single polyphagous fungal species Stigmatomyces dacinus—a known ectoparasite of these fruit flies. This leads to the question: why is S. dacinus rare, when its hosts are widespread and abundant? In addition, the hosts are all Bactrocera, a genus with ~480 species, but 37 Bactrocera species found sympatric with the hosts were never infected. Host‐selection does not appear to be phylogenetically correlated. These results suggest a hidden complexity in how different, but closely related, host species vary in their susceptibility, which somehow limits the abundance and dispersal capability of the fungus., Understanding the mechanisms that determine infection rates will involve both study of host resistance as well as host ecology, as the fungal parasites depend on physical contact of the hosts to be transmitted. Ultimately, this can inform on a broader scale on how host–parasite density systems function in practice and can potentially be applied for pest control.

We describe Dinacoma sanfelipe sp. nov. from southern California, the first new species belonging to the melolonthine scarab beetle genus Dinacoma Casey, 1889 (Scarabaeidae: Melolonthinae: Melolonthini) to be described in 90 years, based upon examination of 141 specimens of that genus. Diagnostic comments, a dichotomous key, photographs of all species of Dinacoma, and a distribution map are presented to facilitate the identification of adult male specimens. One species in the genus is federally listed under the United States Endangered Species act, and all known species may be of conservation concern. Key words: Scarabaeoidea, Melolonthini, scarab beetle, insect conservation, cryptic species

There is growing evidence for the decline of cryptic species across the planet as a result of human activities. Accurate data regarding patterns of poorly known or hard-to-find species diversity is essential for the recognition and conservation of threatened species and ecosystems. Casey’s June beetle Dinacoma caseyi is a federally listed endangered species restricted to the Coachella Valley in southern California, where rapid development is leading to habitat fragmentation. This fragmentation may be disproportionately impacting a wide-range of poorly-dispersing, cryptic species, including Casey’s June beetle, which has flightless females. We characterized 1876 single nucleotide polymorphisms from across the genome along with 1480 bp of mitochondrial DNA of all confirmed extant Dinacoma populations. We found that Dinacoma is isolated into three distinct species, including evidence for a previously undescribed species revealed during this study. Each is restricted to a small part of the inland desert region. Our results suggest unappreciated and fine scale diversity, which may be reflected in the other cryptic species of the region. Patterns of diversity in non-vagile species should guide ongoing conservation planning in the region. These results show that genetic exchange within the one remaining island of beetle habitat (Palm Canyon Wash) is not limited. However, non-vagile species, such as Casey’s June beetle, may not colonize suitable but fragmented habitat islands which presents risks to the species due to habitat loss and periodic natural events that may put the single population at risk of extirpation.

Phylogeographic patterns in phytophagous organisms are often contextualized in light of geographic isolation and ecological (host, habitat) specialization. However, assessing the relative impact of these phenomena is not straightforward, even in areas where phylogeography is well-studied, such as the California Floristic Province. Here, we use genome-wide markers to elucidate population genomic and phylgeographic patterns for a group of monophytophagous butterflies in southern California. This group is of high conservation interest because it includes the El Segundo blue, Euphilotes battoides allyni, one of the first insects listed under the U.S. Endangered Species Act, and a newly discovered population putatively assigned to E. b. allyni. Despite using the same unique host and coastal habitat, our results indicate that the newly discovered populations are not E. b. allyni and are more closely related to geographically proximate populations of the E. battoides group using a different habitat/host combination. Aside from E. b. allyni and the newly discovered populations, the rest of the group shows only fine-scale structure and apparently maintains genetic connectivity throughout southern California, across a vast range of habitats and climates, and on multiple hosts. Thus, habitat and host specialization did not elicit genetic isolation in neighboring populations suggesting that: (1) other phenomena are needed to explain the remarkable and idiosyncratic divergence of these highly restricted, proximate, taxa, and (2) fine-scale genomic markers suggest broader implications for understanding the mechanisms of speciation and reinvestigation of phylogeographic patterns in regions like the California Floristic Province.

Understanding the factors driving ecological and evolutionary interactions of economically important plant species is important for agricultural sustainability. The geography of crop wild relatives, including wild potatoes (Solanum section Petota), have received attention; however, such information has not been analysed in combination with phylogenetic histories, genomic composition and reproductive systems to identify potential species for use in breeding for abiotic stress tolerance. We used a combination of ordinary least-squares (OLS) and phylogenetic generalized least-squares (PGLM) analyses to identify the discrete climate classes that make up the climate niche that wild potato species inhabit in the context of breeding system and ploidy. Self-incompatible diploid or self-compatible polyploid species significantly increase the number of discrete climate classes within a climate niche inhabited. This result was sustained when correcting for phylogenetic non-independence in the linear model. Our results support the idea that specific breeding system and ploidy combinations increase niche breadth through the decoupling of geographical range and niche diversity, and therefore, these species may be of particular interest for crop adaptation to a changing climate.

During the course of a targeted bark beetle survey of the Hawaiian Islands, insect sampling undertaken in native forest biotopes on Moloka‘i island revealed the presence of one native and three exo...

A survey for scolytine bark and ambrosia beetles undertaken on the entomologically understudied and ecologically devastated Hawaiian island of Lāna‘i, revealed the remarkable presence there of Xyleborus mauiensis Perkins, 1900, an endemic Hawaiian ambrosia beetle in the tribe Xyleborini not previously recorded from the island. Its presence on Lāna‘i ‘fills the gap’ in a distribution encompassing the now isolated islands of Molokai and Maui that together with Lanai composed the single historically large island of Maui Nui more than half a million years ago. We emphasize the reliance of X. mauiensis upon its only known host plant, the endemic Hawaiian Cheirodendron trigynum (Araliaceae), and highlight the conservation importance of ensuring the persistence of even a small number of native plants in environments otherwise dominated by exotic flora. We also report five additional new species records for introduced exotic bark and ambrosia beetles in the tribes Xyleborini and Trypophloeini new to Lāna‘i, discussing their significance to our understanding of the distribution of bark beetles in Hawai‘i. We provide a checklist of all Scolytinae recorded from Lāna‘i to date, together with their known host plants and photographs of the newly recorded beetles together with a map indicating where they were sampled.

The utility of a universal DNA ‘barcode’ fragment of 658 base pairs of the Cytochrome C Oxidase I (COI) gene for the recognition of all animal species has been a widely debated topic on theoretical and practical levels. Regardless of its challenges, large amounts of COI sequence data have been produced in the last two decades. To optimally use the data towards reliable species identification will require further steps to validate the method and reference libraries. The fruit fly tribe Dacini holds about a thousand species, of which eighty are pests of economic concern, including some of the world’s foremost fruit and vegetable pests, and there are many morphologically cryptic species complexes in the tribe. Where previous studies showed limited success in using COI to identify Dacini, our results with a highly curated morphological dataset indicate high congruence between morphology and COI: 90% of the species in our 5,576 sequences, 262-species global dataset can be identified with COI alone based on a monophyly criterion. However, in some key pest species belonging to complexes that were previously thought diagnosable with COI, we found that expanded sampling and independent validation of identifications using genomic data revealed introgression of mitochondrial DNA. We find that the informative SNPs are uniformly distributed across the COI gene, and we provide recommendations for standardization. We conclude that reliable molecular identifications with COI require extensive species coverage, population sampling, and genomics-supported reference identifications before they can be validated as a “diagnostic” marker for specific groups.

Understanding the factors driving ecological and evolutionary interactions of economically important plant species is important for sustainability. Niches of crop wild relatives, including wild potatoes (Solanum section Petota), have received attention, however, such information has not been analyzed in combination with phylogenetic histories, genomic composition and reproductive systems. We used a combination of ordinary least-squares (OLS) and phylogenetic generalized least-squares (PGLM) analyses to identify the discrete climate classes that wild potato species inhabit in the context of breeding system and ploidy. Self-incompatible diploid or self-compatible polyploid species significantly increase the number of discrete climate niches inhabited. This result was sustained when correcting for phylogenetic non-independence in the linear model. Our results support the idea that specific breeding system and ploidy combinations increase niche divergence through the decoupling of geographical range and niche diversity, and therefore, these species may be of particular interest for crop adaptation to a changing climate.

Allopatric speciation should be the dominant model of diversification across archipelagos because islands naturally promote isolation. It also follows that ecologically similar, vagile species should be more resistant to this kind of isolation due to dispersal and unifying selection. In a closely-related group of endemic Hawaiian hawkmoths, we found confounding patterns of inter-island connectivity and speciation that did not correlate with vagility, ecological specialization, or island age. Speciation occurred both in allopatric and sympatric taxa, with only the oldest and youngest islands fostering single-island endemic species. The intermediately-sized, central islands supported a combination of endemic and more widely-occurring lineages, suggesting no clear pattern leading to the current diversity in Hawaii. While some species are relatively common, others are apparently extinct or very rare, even on the same island. Further research into the specific mechanisms for these patterns in Hyles may prove broadly informative for understanding both cladogenesis and improving conservation planning. Our study identifies one new species endemic to Kauai and unique mitochondrial lineages in H. perkinsi, which may prove to be new species.

Adaptive radiation plays a fundamental role in our understanding of the evolutionary process. However, the concept has provoked strong and differing opinions concerning its definition and nature among researchers studying a wide diversity of systems. Here, we take a broad view of what constitutes an adaptive radiation, and seek to find commonalities among disparate examples, ranging from plants to invertebrate and vertebrate animals, and remote islands to lakes and continents, to better understand processes shared across adaptive radiations. We surveyed many groups to evaluate factors considered important in a large variety of species radiations. In each of these studies, ecological opportunity of some form is identified as a prerequisite for adaptive radiation. However, evolvability, which can be enhanced by hybridization between distantly related species, may play a role in seeding entire radiations. Within radiations, the processes that lead to speciation depend largely on (1) whether the primary drivers of ecological shifts are (a) external to the membership of the radiation itself (mostly divergent or disruptive ecological selection) or (b) due to competition within the radiation membership (interactions among members) subsequent to reproductive isolation in similar environments, and (2) the extent and timing of admixture. These differences translate into different patterns of species accumulation and subsequent patterns of diversity across an adaptive radiation. Adaptive radiations occur in an extraordinary diversity of different ways, and continue to provide rich data for a better understanding of the diversification of life.

Recent snap-shot surveys for fruit flies in Vietnam in 2015 and 2017 using traps baited with the male Dacinae fruit fly lures methyl eugenol, cue-lure and zingerone, collected 56 species, including 11 new country records and another 11 undescribed species, four of which are described in this paper. This increases the number of described species known to occur in Vietnam from 78 to 93. Species accumulation curves, based on the Chao 2 mean estimate, suggest that we collected 60–85 % of the local fauna at the sites sampled, and that species diversity decreases with increasing latitude. The four new species are named: Bactrocera (Tetradacus) ernesti Leblanc & Doorenweerd sp. n., B. (Asiadacus) connecta Leblanc & Doorenweerd sp. n., B. (Parazeugodacus) clarifemur Leblanc & Doorenweerd sp. n., and B. (Bactrocera) adamantea Leblanc & Doorenweerd sp. n. In addition to morphological data COI DNA sequence data of both the COI-5P and COI-3P mitochondrial DNA gene regions is provided. Three of the four newly described species are morphologically and genetically easily distinguished from all other members of Dacini. Bactroceraclarifemursp. n. is superficially similar to B.pendleburyi (Perkins) based on morphology, but there are several apomorphic characters to distinguish the two. Both COI and a segment of the nuclear gene Elongation Factor 1 alpha separate the two species as well.

A fruit fly survey in the Sinharaja and Knuckles National Parks in Sri Lanka (2016), using traps baited with the male lures methyl eugenol, cue-lure, and zingerone, yielded 21 species of Dacini fruit flies. Of these, three species, viz.BactroceraamarambalensisDrew,B.dongnaiaeDrew & Romig, andB.rubigina(Wang & Zhao), are new country occurrence records, and Dacus (Mellesis) ancoralis Leblanc & Doorenweerd,sp. n.is described as a new species. The Sri Lankan Dacini fruit fly fauna is now comprised of 39 species.

The Mariana eight-spot butterfly (Hypolimnas octocula marianensis) and the Mariana wandering butterfly (Vagrans egistina) are endemic to the Mariana Islands and both have recently been listed as federally protected under the U.S. Endangered Species Act. We conducted both targeted surveys and grid transect searches on Guam and targeted surveys across the islands of Saipan, Tinian and Rota to locate native hostplants, eggs, caterpillars and adults of these rare insects. Despite having a relatively common hostplant, V. egistina was not found during this study, even in places it had last been found. Although various life stages of H. o. marianensis were documented, the hostplants of this species were heavily impacted by grazing of introduced ungulates; only in native limestone forest with jagged tower karst topography, did hostplants persist, and the butterfly with them. The reasons for the disappearance of V. egistina are not clear, but do not appear to be related to hostplant availability. Our surveys suggest that control of invasive ungulates on Guam will be the single most effective conservation action for Mariana eight-spot recovery, and is essential to any chance of long-term persistence for the species there. H. o. marianensis has significant, unoccupied, hostplant patches on the three northern islands (Rota, Tinian, and Saipan) which might be considered as sites for future translocation and reintroduction efforts, in order to reduce the risk of extinction.

The lepidopteran herbivore Secusio extensa (Erebidae: Arctiinae) was purposefully released in Hawaii in 2013 to control Madagascar fireweed, Senecio madagascariensis (Asteraceae: Senecioneae), an invasive weed of rangelands and other open areas. In conjunction with this biocontrol effort, we conducted pre- and post-release monitoring of S. madagascariensis in field plots, and post-release monitoring of non-target plants. Secusio extensa successfully established on the two islands where it was released, dispersed widely, and even colonized a neighboring island. However, in the first three years after release, S. extensa could only be found sporadically and in low abundances on its target host. In contrast, it underwent population outbreaks on the related, alternative host, Cape ivy (Delairea odorata, Asteraceae: Senecioneae), which is also a noxious weed in Hawaii. In addition to D. odorata, we observed S. extensa to feed on only two other related non-target plants in the tribe Senecioneae, among 24 species monitored. In several microsites supporting higher densities of S. extensa on S. madagascariensis, larval abundances peaked during a short period in the spring, but were insufficiently high to cause substantial damage to affected plants. The causes for low larval densities of S. extensa on its target host are unclear. We found no strong evidence for parasitism or predation of S. extensa larvae. However, females preferred to oviposit on D. odorata over S. madagascariensis, and larvae exhibited a marginally significant preference for feeding on D. odorata over S. madagascariensis. This preference, along with lower nutritional quality of S. madagascariensis relative to D. odorata, may explain why S. extensa has been unable to build large populations on its intended target, but has done so on an alternate host. Clarifying the roles of these mechanisms may help predict the continuing performance of S. extensa in controlling S. madagascariensis.

Molecular and morphological research often suggest conflicting results. Selective pressure on certain morphologies can confound understanding of evolutionary relationships. Dacini is one of the most diverse tribes of tephritid flies and contains many economically important pest species. Their black and yellow patterned body markings are presumed to act as wasp mimicry, and the characters separating species and groups are limited and in some cases phenotypically plastic. The traditional taxonomy of the tribe is controversial because groupings are based on unique combinations of morphological characters without the use of cladistic methods, though recent phylogenetic and taxonomic analyses have resulted in significant changes to their taxonomy. The monophyly of the three largest genera in the tribe has been tested with only small numbers of representatives per genus and a limited number of genes. To further understand the taxonomy and evolution of Dacini we sequenced seven genes from 167 Dacini species and five dipteran outgroups to construct a robust phylogeny and test phylogenetic relationships between genera, subgenera, and species complexes. Our phylogeny confirms the monophyly of Dacus, Bactrocera, and Zeugodacus. However, most groups below the genus level are not monophyletic, and only through further revision will we be able to understand their evolution and clarify the taxonomy within this tribe.

The correct application of the scientific names of species is neither easy nor trivial. Mistakes can lead to the wrong interpretation of research results or, when pest species are involved, inappropriate regulations and limits on trade, and possibly quarantine failures that permit the invasion of new pest species. Names are particularly challenging to manage when groups of organisms encompass a large number of species, when different workers employ different philosophical views, or when species are in a state of taxonomic flux. The fruit fly tribe Dacini is a species-rich taxon within Tephritidae and contains around a fifth of all known species in the family. About 10% of the 932 currently recognized species are pests of commercial fruits and vegetables, precipitating quarantines and trade embargos. Authoritative species lists consist largely of scattered regional treatments and outdated online resources. The checklist presented here is the first global overview of valid species names for the Dacini in almost two decades, and includes new lure records. By publishing this list both in paper and digitally, we aim to provide a resource for those studying fruit flies as well as researchers studying components of their impact on agriculture. The list is largely a consolidation of previous works, but following the results from recent phylogenetic work, we transfer one subgenus and eight species to different genera: members of the Bactrocera subgenus Javadacus Hardy, considered to belong to the Zeugodacus group of subgenera, are transferred to genus Zeugodacus; Bactrocera pseudocucurbitae White, 1999, stat. rev., is transferred back to Bactrocera from Zeugodacus; Zeugodacus arisanicus Shiraki, 1933, stat. rev., is transferred back to Zeugodacus from Bactrocera; and Z. brevipunctatus (David & Hancock, 2017), comb. n.; Z. javanensis (Perkins, 1938), comb. n.; Z. montanus (Hardy, 1983), comb. n.; Z. papuaensis (Malloch, 1939), comb. n.; Z. scutellarius (Bezzi, 1916), comb. n.; Z. semisurstyli (Drew & Romig, 2013), comb. n.; and Z. trilineatus (Hardy, 1955), comb. n. are transferred from Bactrocera to Zeugodacus.

The California Floristic province is a biodiversity hotspot. Understanding the phylogeographic patterns that exist in this diverse region is essential to understanding its evolution and for guiding conservation efforts. Calosaturnia is a charismatic silkmoth genus endemic to large portions of the region with three described species, C. mendocino, C. walterorum, and C. albofasciata. We sampled all three species from across their ranges, sequenced 1463 bp of mitochondrial COI and 1941 bp of nuclear DNA from three genes, and reconstructed phylogenetic relationships and estimated divergence times within the lineages. All three species show pronounced evidence of isolation and, in two cases, secondary reconnection. An unexpected monophyletic mtDNA lineage was found in the Central Coast region, in a region thought to represent an intergrade between C. mendocino and C. walterorum. Our genetic data also significantly revise previous hypotheses as to which species occur in which regions, suggesting that historical ecological changes around four Ma ago isolated some lineages, and a secondary isolation event two Ma ago led to isolation of populations both in the Central Coast region and the southern Sierra Nevada. Our results add to a currently under-appreciated pattern suggesting that coastal Central California is not a transition zone between Northern and Southern California Floristic Province faunas but rather its own unique, periodically isolated, biogeographic region. They also suggest cryptic diversity may be present in many other currently unrecognized groups. Additional research should focus on this central California region because many species may be highly restricted in range and in need of conservation attention.

Population genetics is a powerful tool for invasion biology and pest management, and useful for a range of questions from tracing invasion pathways to informing management decisions with inference of population demographics. Genomics greatly increases the resolution of population-scale analyses, yet outside of model species with extensive genomic resources, few studies have used population genomics in invasion biology. We use genome-wide single nucleotide polymorphisms (SNPs) to investigate population genomic structure with samples from across the range of melon fly, Bactrocera cucurbitae (Coquillett, 1849), a highly polyphagous pest of commercial produce. We then make use of a chromosome-scale genome assembly and gene set to compare signatures of selection across the melon fly’s genome, both across our sampling as a whole and in the context of two independent, established introductions. Using multiple approaches, we find support for six genetic clusters across melon fly’s distribution. Some of these agree with previously identified genetic clusters using microsatellites, but consensus of clusters in mainland and oceanic southeast Asia is confounded by variable sampling between studies. We find few adaptive signatures across the genome, and virtually no unique signatures when comparing the two independent introductions, which suggests that similar management strategies are appropriate across melon fly’s range. This is the first use of genome-wide data to characterize population structure in tephritid fruit fly pests, and our SNP dataset provides a foundation for objective and cost-effective genotyping of previously collected melon fly specimens. Future research needs to focus on truly comprehensive sampling across melon fly’s range to overcome the historic variability of range-wide estimates of population structure for this pest.

The Hemileuca maia species complex occurs across the North American continent and consists of six named taxa, and several others that were recently synonymized. Taxa exhibit a wide span of adult flight periods, dramatic shifts in host-plant use and occur in a range of habitats, all of which would suggest unrecognized diversity. We used one mitochondrial and three nuclear genes to generate 3900 bp per individual, including samples from every ecotype in the species group across the United States from New England to central Florida to California. We assessed phylogenetic relationships using both maximum likelihood and Bayesian phylogenetic methods. Results suggest very low levels of divergence across most of the continent and low levels of genetic structure – even between some recognized species that maintain clear ecological difference in sympatry. Our results suggest that meaningful and localized ecological divergence may occur in the absence of easily recognizable genetic divergence, due to either ongoing gene flow or the recent diversification in the group.

Two new endemic Hawaiian species of Agrotis Ochsenheimer (Noctuidae) are described: A. helela and A. kuamauna. Both species are day-flying and occur at high-elevations. Observations of adult and larval morphology and biology are included, as well as illustrations of adult moths and genitalia for both sexes.