Review of New Zealand Cryptamorpha (Coleoptera: Silvanidae), with a description of a new species from the Three Kings Islands

A new species of silvanid beetle, Cryptamorpha triregia sp. n. is described from the Three Kings Islands, New Zealand. A key to the New Zealand Cryptamorpha species and diagnoses to the previously described Cryptamorpha brevicornis (White) and Cryptamorpha desjardinsi (Guérin-Méneville) are provided. Examination of the type series of Cryptamorpha curvipes Broun and Dendrophagus suturalis White show that C. curvipes is a synonym of C. brevicornis and confirms that D. suturalis is a junior synonym of C. desjardinsi, despite formerly being considered to be a synonym of C. brevicornis. Lectotypes are designated for C. brevicornis and D. suturalis

The conservation status of New Zealand Coleoptera

Forty-five New Zealand beetles (Coleoptera) in 37 families are classified as Threatened: 35 taxa in 10 families are Nationally Critical, seven taxa in five families are Nationally Endangered and three taxa in separate families are Nationally Vulnerable. A further 267 taxa in 31 families are At Risk, consisting mostly (91%) of Naturally Uncommon taxa. Fifty-two taxa in 13 families are Data Deficient and four taxa in three families are Extinct. The largest proportions of Threatened and At Risk species comprise Carabidae (respectively 42.2% and 6.7%) and Tenebrionidae (respectively 29.3% and 22.2%). Many of the threatened Coleoptera are large and flightless which may contribute towards their decline

Reconstructing ancient dispersal through Antarctica: A case study of stream-inhabiting beetles

File replaced (AAM) on 14.8.23 by NK (LDS)Aim Although Antarctica hosted a diverse fauna and flora in the past, its modern climate is too extreme for many lineages: their recent extinction makes it difficult to include the continent in historical biogeographical analyses. We use southern temperate stream‐inhabiting beetles as a model to explore whether Antarctica may be included in historical biogeographic reconstructions in a group absent from Antarctica today, and to test its role in shaping the current distribution of stream‐inhabiting insects. Taxon Coleoptera, Elmidae. Location Southern Hemisphere temperate regions and Antarctica. Methods We included Antarctica in historical biogeographic analyses indirectly, as a component of distance matrices specifying the relative positions of continents, or by specifying Antarctica as a stepping‐stone between remaining continents (in LEMAD). We used a newly constructed dated phylogeny of Elmidae to test the performance of these constrained analyses under different parameter settings and geographical scenarios. Results Antarctica can be implemented into historical biogeographic analyses via indirect constraints to produce biologically relevant reconstructions when long‐distance dispersal events are highly penalized, the maximum number of areas per species is low, and expected extinction rates are high (in LEMAD). Unconstrained models, including those without Antarctica, result in simpler scenarios with fewer biogeographic events and better fit to data. The origin of austral clades of Elmidae post‐date the separation of Gondwanan landmasses. Main Conclusions Antarctica can be included in historical biogeographic reconstructions under a priori assumptions that (1) it was part of the ancient biogeography of the clade, (2) the taxon has limited dispersal ability, making long‐distance dispersal highly unlikely and (3) maximum range size is limited. These assumptions may be biologically justified for many animal groups. Over‐water dispersal has been crucial in shaping the modern distribution of austral stream‐inhabiting beetles, likely facilitated by ocean currents and dispersal through Antarctica until the Oligocene

Determining the origin and age of the Westland beech (Nothofagus) gap, New Zealand, using fungus beetle genetics

The formation and maintenance of the Nothofagus beech gap in the South Island, New Zealand, has been the focus of biogeographical debate since the 1920s. We examine the historical process of gap formation by investigating the population genetics of fungus beetles: Brachynopus scutellaris (Staphylinidae) inhabits logs and is absent from the beech gap, and Hisparonia hystrix (Nitidulidae) is contiguous through the gap and is found commonly on sooty mould growing on several plant species. Both species show distinctive northern and southern haplotype distributions while H. hystrix recolonized the gap as shown by definitive mixing. B. scutellaris shows two major haplotype clades with strong geographical concordance, and unlike H. hystrix, has clearly defined lineages that can be partitioned for molecular dating. Based on coalescence dating methods, disjunct lineages of B. scutellaris indicate that the gap was formed less than 200 000 years ago. Phylogenetic imprints from both species reveal similar patterns of population divergence corresponding to recent glacial cycles, favouring a glacial explanation for the origin of the gap. Post-gap colonization by H. hystrix may have been facilitated by the spread of Leptospermum scoparium host trees to the area, and they may be better at dispersing than B. scutellaris which may be constrained by fungal host and/or microhabitat. The gap-excluded species B. scutellaris is found in both beech and podocarp-broadleaf forests flanking the Westland gap and its absence in the gap may be related to incomplete recolonization following glacial retreat. We also discuss species status and an ancient polymorphism within B. scutellaris