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Dung beetles are described as key ecosystem service providers. Because of ecosystem benefits from their activity, approval has been granted to import dung-burying beetles for release into pasture systems in New Zealand. Concerns remain, however, about the impact of dung beetle tunnelling and burying activity on the leaching of contaminants through soil. To assess the quality of water leaching from soil cores containing dung beetles, a trial was conducted using 12 intact Allophanic soil core lysimeters under in situ soil moisture and temperature regimes. Four lysimeters received dung and beetles (Geotrupes spiniger and Onthophagus taurus), four received dung and no beetles and four (controls) received no dung and no beetles. The quality of water was assessed by monitoring leachate samples for Escherichia coli and total N and P for 6 months. Key findings of the study were that concentrations of E. coli, N and P leaching through the lysimeters treated with dung beetles were not significantly different from soils without dung beetles. In addition, where dung was buried there was a significant decrease in E. coli and total N and P in surface soil compared with the lysimeters receiving dung only. Results from this study suggest dung beetle tunnelling and burying activity does not negatively impact the quality of water leaching through Allophanic soil. Keywords: Escherichia coli, Geotrupes spiniger, leaching, lysimeters, nitrogen, Onthophagus taurus, phosphorus., Introduction In an international context New Zealand is unique, having a population of ~4.7 million people, but much higher numbers of fanned animals. In 2016 it was estimated that New [...]

1. Whether the release of non‐native insect species benefits or harms ecosystem services has been the subject of debate. In New Zealand, the release of new non‐native dung beetle species was intended to enhance ecosystem services but concerns were raised over possible negative effects. 2. Field cage trials used three newly released dung beetle species to investigate two concerns: that soil disturbance from dung beetle activity increases soil losses in runoff after rainfall; and that dung burial increases survival of infective parasitic nematodes on pasture. 3. Three treatments – dung + beetles, dung‐only, and controls (without dung or beetles) – were applied on each of three soil types with different permeability: sandy loam, clay loam, and compacted clay. 4. Dung beetle activity resulted in significant reductions of 49% and 81% in mean surface runoff volume, depending on simulated rainfall intensity. Amounts of sediment in the runoff did not change under an extreme rainfall simulation, but in a less extreme rainfall simulation the presence of dung beetles resulted in a 97% reduction in mean sediment amount in runoff. 5. The numbers of infective third‐stage nematode larvae recovered from foliage varied considerably between soil types and through time; however, dung beetle activity reduced overall mean nematode numbers on grass around the dung pats by 71%. 6. This study adds to global evidence that dung beetles can improve agricultural ecosystem services by providing data on services that have rarely been investigated: reduced runoff/soil losses through increased soil porosity, and reductions in parasitic nematodes. [ABSTRACT FROM AUTHOR]

Madagascar, the world's fourth largest island, has a long history of isolation (160 million years) and a wide range of climates and ecosystems which have in turn resulted in high levels of endemism across different taxonomic levels. Although Madagascar has a rich dung beetle fauna that belongs to various tribes only three species of the Scarabaeini are found there, namely Scarabaeus viettei, S. radama and S. sevoistra. These three species are superficially quite distinctive and have, consequently, had a variable taxonomic history since the first one was described in 1896. The morphological differences between these species resulted in them being placed in different genera at different times. However, currently, based on cladistic analyses, they are all classified in the genus Scarabaeus. In this study, two of the species, S. viettei and S. radama, were included in a phylogenetic analysis based on two mitochondrial gene regions - cytochrome oxidase I (COI) and 16S rRNA - and a 247 morphological and behavioural dataset of 23 members of the Scarabaeinae. A Bayesian phylogram supports the monophyly of the genus Scarabaeus, with the two species from Madagascar appearing sister to three species of Scarabaeus from south-west Africa. Estimated times of divergence based on published mutation rates of 0.012 and 0.0075 for COI indicate that a shared African/Madagascan origin occurred around 15.18 or 24.15 million years ago, respectively. is study is another example in support of Madagascan fauna having an African origin with colonisation having occurred via dispersal as opposed to ancient vicariant events. [ABSTRACT FROM AUTHOR]

Volcanic islands with well-characterized geological histories can provide ideal templates for generating and testing phylogeographic predictions. Many studies have sought to utilize these to investigate patterns of colonization and speciation within groups of closely related species across a number of islands. Here we focus attention within a single volcanic island with a well-characterized geological history to develop and test phylogeographic predictions. We develop phylogeographic predictions within the island of La Palma of the Canary Islands and test these using 69 haplotypes from 570 base pairs of mitochondrial DNA cytochrome oxidase II sequence data for 138 individuals of Brachyderes rugatus rugatus, a local endemic subspecies of curculionid beetle occurring throughout the island in the forests of Pinus canariensis. Although geological data do provide some explanatory power for the phylogeographic patterns found, our network-based analyses reveal a more complicated phylogeographic history than initial predictions generated from data on the geological history of the island. Reciprocal illumination of geological and phylogeographic history is also demonstrated with previous geological speculation gaining phylogeographic corroboration from our analyses. [ABSTRACT FROM AUTHOR]

A phylogenetic analysis of the Scarabaeini, based on 244 morphological characters, including 154 multistate and three biological characters, is presented. Tree topologies generated from unweighted data and some weighted algorithms are similar and support only two clades in the tribe representing the generaScarabaeusL. andPachylomerusBertoloni. The only supported subordinate groups treated in this paper as subgenera areKheperKirbystat. nov.,PachysomaMacLeay,ScarabaeolusBalthasar andSceliagesWestwoodstat. nov.DrepanopodusJanssenssyn. nov.is synonymised withScarabaeusand six additional names,MadateuchusPaulian,MnematidiumRitsema,MnematiumMacLeay,NeateuchusGillet,NeomnematiumJanssens andNeopachysomaFerreira, remain synonyms. A single origin of flightlessness is supported with the subgenusPachysoma, the most derived lineage in this clade. Rolling dung balls backwards is the ancestral behaviour and predominant mode of food relocation in Scarabaeini, although tunnelling, forward pushing, and carrying also are utilized by some lineages. Pushing food has evolved independently inSceliagesspecies andS.galenus(Westwood) and a novel mode of forward food relocation by dragging evolved in the subgenusPachysoma. Feeding on wet dung is the plesiomorphic condition and maintained by the majority of species in the tribe. The most unusual feeding behaviours in the tribe are represented by the obligate millipede-feeding species ofSceliagesand the dry dung pellet and/or detritus feeders ofPachysoma. [ABSTRACT FROM AUTHOR]