Multiple hybridization events and repeated evolution of homoeologue expression bias in parthenogenetic, polyploid New Zealand stick insects.

During hybrid speciation, homoeologues combine in a single genome. Homoeologue expression bias (HEB) occurs when one homoeologue has higher gene expression than another. HEB has been well characterized in plants but rarely investigated in animals, especially invertebrates. Consequently, we have little idea as to the role that HEB plays in allopolyploid invertebrate genomes. If HEB is constrained by features of the parental genomes, then we predict repeated evolution of similar HEB patterns among hybrid genomes formed from the same parental lineages. To address this, we reconstructed the history of hybridization between the New Zealand stick insect genera Acanthoxyla and Clitarchus using a high-quality genome assembly from Clitarchus hookeri to call variants and phase alleles. These analyses revealed the formation of three independent diploid and triploid hybrid lineages between these genera. RNA sequencing revealed a similar magnitude and direction of HEB among these hybrid lineages, and we observed that many enriched functions and pathways were also shared among lineages, consistent with repeated evolution due to parental genome constraints. In most hybrid lineages, a slight majority of the genes involved in mitochondrial function showed HEB towards the maternal homoeologues, consistent with only weak effects of mitonuclear incompatibility. We also observed a proteasome functional enrichment in most lineages and hypothesize this may result from the need to maintain proteostasis in hybrid genomes. Reference bias was a pervasive problem, and we caution against relying on HEB estimates from a single parental reference genome.

Wing pattern variation and DNA barcodes defy taxonomic splitting in the New Zealand Pimelea Looper Notoreas perornata (Walker) (Lepidoptera: Geometridae: Larentiinae): the importance of populations as conservation units.

The endemic Notoreas perornata (Walker, 1863) complex (Lepidoptera: Geometridae: Larentiinae) from the North Island and northern South Island of New Zealand is reviewed. Larvae feed on Pimelea spp. (Thymelaeaceae), frequently in highly fragmented and threatened shrubland habitats. Allopatric populations tend to differ in size and wing pattern characteristics, but not in genitalia; moreover extensive variation renders recognition of subspecies / allopatric species based on any species concept problematic. A mitochondrial DNA gene tree is not congruent with morphology and indicates rapid recent divergence that has not settled into diagnosable lineages. Based on our results, we synonymise Notoreas simplex Hudson, 1898 with N. perornata (Walker, 1863), and retain N. perornata as a single, highly diverse but monotypic species. All known populations are illustrated to display variation. For conservation purposes, we recommend the continued recognition within the species of 10 populations or groups of populations that appear to be on the way to diverging at subspecific level based on morphological and/or DNA data. The conservation status of all these populations is reviewed. One conservation unit, comprising the populations from Westland, has not been seen since 1998 and is feared possibly extinct.

Fast-tracking bespoke DNA reference database generation from museum collections for biomonitoring and conservation.

Despite recent advances in high-throughput DNA sequencing technologies, a lack of locally relevant DNA reference databases limits the potential for DNA-based monitoring of biodiversity for conservation and biosecurity applications. Museums and national collections represent a compelling source of authoritatively identified genetic material for DNA database development, yet obtaining DNA barcodes from long-stored specimens may be difficult due to sample degradation. Here we demonstrate a sensitive and efficient laboratory and bioinformatic process for generating DNA barcodes from hundreds of invertebrate specimens simultaneously via the Illumina MiSeq system. Using this process, we recovered full-length (334) or partial (105) COI barcodes from 439 of 450 (98%) national collection-held invertebrate specimens. This included full-length barcodes from 146 specimens which produced low-yield DNA and no visible PCR bands, and which produced as little as a single sequence per specimen, demonstrating high sensitivity of the process. In many cases, the identity of the most abundant sequences per specimen were not the correct barcodes, necessitating the development of a taxonomy-informed process for identifying correct sequences among the sequencing output. The recovery of only partial barcodes for some taxa indicates a need to refine certain PCR primers. Nonetheless, our approach represents a highly sensitive, accurate and efficient method for targeted reference database generation, providing a foundation for DNA-based assessments and monitoring of biodiversity.

Dataset of host records for introduced parasitoid wasp species (Hymenoptera) in New Zealand.

BACKGROUND: The introduction of species to new regions is occurring at an increasing rate. These introductions typically consist of species that are deliberately introduced for the purposes of biological control of pests or of species that are accidentally introduced through human-mediated transport networks.Understanding the potential and actual impacts of these introduced species requires comprehensive information on their geographic distributions and biological associations.However, apart from a few well-known case studies, such information is lacking for many introduced species which severely hinders further assessment of risks and impact. NEW INFORMATION: A dataset is provided on host associations, geographic distributions and dates of collection for both deliberately and accidentally-introduced parasitoid wasp species (Hymenoptera) in New Zealand. Information was obtained by digitising specimens from the New Zealand Arthropod Collection. Dates of records range from 1921 to 2017.The dataset includes 1265 specimen records, representing 127 parasitoid species from 12 families, with host records for 177 host species from 61 families and eight insect orders.These data provide baseline information to help evaluate the risk from introduced parasitoids to non-target and native species.

Systematics of the New Zealand Weevil Etheophanus Broun (Curculionidae: Molytinae).

Etheophanus Broun is considered a molytine based on the form of the pharyngeal plate, presence of a small spiculum relictum in the male, and presence of a pair of small internal apodemes on the antero-lateral corners of the 5th abdominal ventrite of the female. Examination of primary type specimens and newer material confirm one new species Etheophanus kuscheli sp. n. and two synonomies (Etheophanus nitidellus Broun, 1923 [= Etheophanus obscurus Broun, 1923] and Etheophanus striatus Broun, 1910 [=Etheophanus punctiventris Broun, 1914]). Generic and species diagnoses, a key to the species, and lectotype designations for three species are included. Phylogenetic reconstructions based on a combined analysis of the nuclear 28S rRNA and mitochondrial cytochrome c oxidase subunit I genes confirmed the status of E. kuscheli and a species complex, the E. nitidellus/E. optandus clade distributed in the southern portion of the South Island. The relationship E. pinguis [northern North Island] (E. striatus [southern North Island, northern South Island] (E. kuscheli [northwestern South Island] (E. nitidellus, E. optandus [southwestern North Island]) corresponds to geographic patterns found in other beetle lineages. Etheophanus striatus is composed of three lineages, one widespread in the north and south islands and two allopatric populations in the northwest South Island. The E. nitidellus/E. optandus complex includes four distinct lineages, one restricted to Fiordland, the other three sympatric in the region affected by the Haast Corridor.