Tritoniid sea slugs are specialised predators that feed on a variety of octocorals, including soft corals, gorgonians and sea pens. Trivettea papalotla is a recently described species found in Baja California and mainland Mexico that is unusual in its morphology and feeding behaviour. It is the first tritoniid nudibranch known to feed on zoanthid anthozoans, specifically on an undescribed species of the genus Epizoanthus. Trivettea papalotla also has retractable respiratory structures, prominent dorsal vessels and several other traits not found in any other species of the Tritoniidae. In its original description these unique features of T. papalotla were considered autapomorphies, and the species was tentatively placed within Tritonia based on a morphological phylogenetic analysis. Subsequently, the monotypic genus Trivettea was erected for T. papalotla based on unpublished molecular data. In the present study, the phylogenetic placement of Trivettea is investigated based on molecular data. These phylogenies show T. papalotla is not nested within Tritonia or Tritoniidae and instead appears to be a basal, distinct cladobranch. However, the analyses conducted resulted in poorly resolved basal relationships, suggesting additional markers are probably necessary to fully resolve the phylogeny for the Cladobranchia.

The larvae of stoneflies (Plecoptera) are important indicators for monitoring aquatic ecosystems, but the immature stages of some relevant species have not been described. Here, mitochondrial gene sequences are used to associate the adult and larval life stages for species of Newmanoperla McLellan. This study finds molecular and morphological support for five species, which include the four previously described species (N. exigua, N. hackeri, N. prona and N. thoreyi) and a newly recognised species, N. theischingeri, sp. nov., which is described herein. Molecular divergences between species for the COI fragment had minimum values of 15–18% while the maximum intraspecific divergence was 6–9%, and there was no overlap between species. Morphological characters for distinguishing the larvae of the five species were observed on the femora and included variations in the type of setation present and the area of occurrence. The combination of molecular and morphological methods enabled the larval morphology to be reassessed and has led to the following outcomes: the first formal generic larval description, a newly recognised species, updated descriptions for larvae of all species of Newmanoperla and a dichotomous key to larvae.

The evolutionary history of the crane fly genus Lipsothrix Lowe, 1873 was examined through a systematic revision of specimens maintained in natural history collections, parsimony analysis using TNT based on immature and adult morphology, and dispersal–vicariance analyses in RASP (Bayesian and S-DIVA). The genus Lipsothrix was found to contain 29 valid species, one subspecies (L. nobilis iranica) and three species maintained but in need of further evaluation (Lipsothrix burmica, L. heitfeldi, L. yakushimae). One species complex (L. shasta complex) was further resolved using ordination and cluster analyses. One new species is described, L. nullusarma, sp. nov., and three species are synonymised (L. fulva, L. mirifica, L. yamamotoana omogoensis). Phylogenetic analysis recovered a strongly supported and monophyletic Lipsothrix. The historical biogeographical analyses of Lipsothrix inferred an ancestral area in the Western Palearctic region that likely dates to the Eocene. One, or several, dispersal events occurred from the Western Palearctic before major diversification events occurred in the Oriental and Eastern Palearctic   Nearctic regions. Two major paleogeographical developments occurring in the Oriental and Eastern Palearctic   Nearctic regions are largely responsible for Lipsothrix diversification, the collision of the Indian plate with Asia and the rise of the trans-Beringian land bridges during the Tertiary and Quaternary.

Australia houses some unusual biota (insects included), much of which is undescribed. Cystococcus Fuller (Hemiptera : Sternorrhyncha : Coccoidea : Eriococcidae) currently comprises two species, both of which induce galls exclusively on bloodwoods (Myrtaceae: Corymbia Hill & Johnson). These insects display sexual dichronism, whereby females give birth first to sons and then to daughters. Wingless first-instar females cling to their winged adult brothers and are carried out of the maternal gall when the males fly to find mates – a behaviour called intersexual phoresy. Here, we use data from two gene regions, as well as morphology and host-use of the insects, to assess the status of a previously undescribed species. We describe this newly recognised species as Cystococcus campanidorsalis, sp. nov. Semple, Cook & Hodgson, redescribe the two existing species – C. echiniformis Fuller and C. pomiformis (Froggatt), designate a lectotype for C. echiniformis, and provide the first descriptions of adult males, and nymphal males and females for the genus. We have also reinterpreted a key morphological character of the adult females. This paper provides a foundation for further work on the genus, which is widespread across northern Australia and could prove to be useful for studies on biogeography and bloodwood ecosystems.