Body-size-dependent effects of landscape-level resource energetics on pollinator abundance in woodland remnants.

Land use change alters floral resource availability, thereby contributing to declines in important pollinators. However, the severity of land use impact varies by species, influenced by factors such as dispersal ability and resource specialization, both of which can correlate with body size. Here. we test whether floral resource availability in the surrounding landscape (the 'matrix') influences bee species' abundance in isolated remnant woodlands, and whether this effect varies with body size. We sampled quantitative flower-visitation networks within woodland remnants and quantified floral energy resources (nectar and pollen calories) available to each bee species both within the woodland and the matrix. Bee abundance in woodland increased with floral energy resources in the surrounding matrix, with strongest effects on larger-bodied species. Our findings suggest important but size-dependent effects of declining matrix floral resources on the persistence of bees in remnant woodlands, highlighting the need to incorporate landscape-level floral resources in conservation planning for pollinators in threatened natural habitats.

Forest edges increase pollinator network robustness to extinction with declining area.

Edge effects often exacerbate the negative effects of habitat loss on biodiversity. In forested ecosystems, however, many pollinators actually prefer open sunny conditions created by edge disturbances. We tested the hypothesis that forest edges have a positive buffering effect on plant-pollinator interaction networks in the face of declining forest area. In a fragmented land-bridge island system, we recorded ~20,000 plant-pollinator interactions on 41 islands over 3 yr. We show that plant richness and floral resources decline with decreasing forest area at both interior and edge sites, but edges maintain 10-fold higher pollinator abundance and richness regardless of area loss. Edge networks contain highly specialized species, with higher nestedness and lower modularity than interior networks, maintaining high robustness to extinction following area loss while forest interior networks collapse. Anthropogenic forest edges benefit community diversity and network robustness to extinction in the absence of natural gap-phase dynamics in small degraded forest remnants.

Four new species of Australian velvet ants (Hymenoptera: Mutillidae, Aglaotilla) reared from bee and wasp nests, with a review of Australian mutillid host records.

Four species of velvet ants (Mutillidae) were reared from nests of solitary bees and wasps collected using trap nests in southwest Australia and identified using morphological and DNA barcoding approaches. All four species, Aglaotilla micra sp. nov., A. lathronymphos sp. nov., A. chalcea sp. nov. and A. schadophaga sp. nov., are described as new, the last three from both sexes. A. micra, A. lathronymphos and A. chalcea are parasitoids of wasps in the genera Pison and Aulacophilinus (Crabronidae), with A. chalcea also recorded from Paralastor (Vespidae). Aglaotilla schadophaga is a parasitoid of bees in the genus Megachile (Megachilidae). The biologies and known hosts of Australian Mutillidae are reviewed. Photographs are also provided of type material for Ephutomorpha aeneidorsis Turner, 1914 (=Aglaotilla discolor Brothers, 2018), Mutilla metallica Smith, 1855 and Ephutomorpha subelegans Rayment, 1933. The lectotype of E. subelegans is formally designated.