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1. Assessing the Australian Termite Diversity Anomaly: How Habitat and Rainfall Affect Termite Assemblages

   https://doi.org/10.3389/fevo.2021.657444  

   Clement, Rebecca A.; Flores-Moreno, Habacuc; Cernusak, Lucas A.; Cheesman, Alexander W.; Yatsko, Abbey R.; Allison, Steven D.; Eggleton, Paul; Zanne, Amy E. (April 2021, Frontiers in Ecology and Evolution)

   null (Ed.)

   Termites are important ecosystem engineers in tropical habitats, with different feeding groups able to decompose wood, grass, litter, and soil organic matter. In most tropical regions, termite abundance and species diversity are assumed to increase with rainfall, with highest levels found in rainforests. However, in the Australian tropics, this pattern is thought to be reversed, with lower species richness and termite abundance found in rainforest than drier habitats. The potential mechanisms underlying this pattern remain unclear. We compared termite assemblages (abundance, activity, diversity, and feeding group composition) across five sites along a precipitation gradient (ranging from ∼800 to 4,000 mm annual rainfall), spanning dry and wet savanna habitats, wet sclerophyll, and lowland and upland rainforests in tropical North Queensland. Moving from dry to wet habitats, we observed dramatic decreases in termite abundance in both mounds and dead wood occupancy, with greater abundance and activity at savanna sites (low precipitation) compared with rainforest or sclerophyll sites (high precipitation). We also observed a turnover in termite species and feeding group diversity across sites that were close together, but in different habitats. Termite species and feeding group richness were highest in savanna sites, with 13 termite species from wood-, litter-, grass-, dung-, and soil-feeding groups, while only five termite species were encountered in rainforest and wet sclerophyll sites—all wood feeders. These results suggest that the Australian termite diversity anomaly may be partly driven by how specific feeding groups colonized habitats across Australia. Consequently, termites in Australian rainforests may be less important in ecosystem processes, such as carbon and nutrient cycling during decomposition, compared with termites in other tropical rainforests. 

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2. The other side of the Sahulian coin: biogeography and evolution of Melanesian forest dragons (Agamidae)

   https://doi.org/10.1093/biolinnean/blz125  

   Tallowin, Oliver_J S; Meiri, Shai; Donnellan, Stephen C; Richards, Stephen J; Austin, Christopher C; Oliver, Paul M (November 2019, Biological Journal of the Linnean Society)

   Abstract New Guinea has been considered both as a refuge for mesic rainforest-associated lineages that contracted in response to the late Cenozoic aridification of Australia and as a centre of biotic diversification and radiation since the mid-Miocene or earlier. Here, we estimate the diversity and a phylogeny for the Australo-Papuan forest dragons (Sauria: Agamidae; ~20 species) in order to examine the following: (1) whether New Guinea and/or proto-Papuan Islands may have been a biogeographical refuge or a source for diversity in Australia; (2) whether mesic rainforest environments are ancestral to the entire radiation, as may be predicted by the New Guinea refuge hypothesis; and (3) more broadly, how agamid ecological diversity varies across the contrasting environments of Australia and New Guinea. Patterns of lineage distribution and diversity suggest that extinction in Australia, and colonization and radiation on proto-Papuan islands, have both shaped the extant diversity and distribution of forest dragons since the mid-Miocene. The ancestral biome for all Australo-Papuan agamids is ambiguous. Both rainforest and arid-adapted radiations probably started in the early Miocene. However, despite deep-lineage diversity in New Guinea rainforest habitats, overall species and ecological diversity is low when compared with more arid areas, with terrestrial taxa being strikingly absent. 

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3. Pine‐fungal co‐invasion alters whole‐ecosystem properties of a native eucalypt forest

   https://doi.org/10.1111/nph.70363  

   Vietorisz, Corinne R; Nash, Jake A; Siggers, J Alexander; Leander, Elena J; Bock, Beatrice M; Camuy‐Vélez, Lennel A; Hall, Allie Jasmine; Jaros, Joseph E; Kuehn, Kevin A; Lai, Edith Y; et al (September 2025, New Phytologist)

   Summary Pine‐fungal co‐invasions into native ecosystems are increasingly prevalent across the southern hemisphere. In Australia, invasive pines slowly spread into native eucalypt forests, creating novel mixed forests. We sought to understand how pine‐fungal co‐invasions impact interconnected above‐ and belowground ecosystem characteristics.We sampled beneath maturePinus radiataandEucalyptus racemosain a pine‐invaded eucalypt forest in New South Wales, Australia. We measured microbial community composition via amplicon sequencing of 16S, ITS2, and 18S rDNA regions, microbial metabolic activity via Biolog plate substrate utilization, and soil, leaf litter, and understory plant characteristics.Pines were associated with decreased topsoil moisture, increased pine litter, and decreased eucalypt litter total phosphorus content. Soils and roots beneath pines had distinct microbial community composition and activity relative to eucalypts, including decreased bacterial diversity, decreased microbial utilization of several C‐ and N‐rich substrates, and enrichment of pine‐associated ectomycorrhizae. Introduced suilloid fungi were abundant across both pine and eucalypt soils and roots. Many ecosystem impacts increased with pine size.Invasive pines and their ectomycorrhizae have significant impacts on eucalypt forest properties as they grow. Interconnected impacts at the scale of individual trees should be considered when managing invaded forests and predicting effects of pine invasions. 

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4. Continental‐scale interactions of Australian showy mistletoes and their hosts

   https://doi.org/10.1002/ajb2.16443  

   Santiago‐Rosario, Luis Y; Book, Jordan; Mathews, Sarah (December 2024, American Journal of Botany)

   Abstract PremiseShowy mistletoes are obligate hemiparasites of woody plants. Host specificity is therefore a fundamental determinant of mistletoe diversity, persistence, geographic distribution, and abundance. Investigations of host specificity in Australian Loranthaceae have focused mostly on host range (taxon counts), but additional insights into specificity are gained by quantifying mistletoe prevalence on taxa in their host range and by exploring specificity in a phylogenetic context. MethodsWe estimated measures of host specificity to characterize mistletoe–host interactions at a continental scale by using occurrence records in the Atlas of Living Australia. We calculated host taxon richness, mistletoe prevalence, and phylogenetic diversity, and used rarefaction curves to evaluate sampling coverage. ResultsMany mistletoe taxa were represented by few records that listed the host, which often was identified to genus only. Mistletoe genera were recorded on 29 orders and 80 families, and no association was observed between host richness and number of records per genus. Rarefaction curves suggested that additional host orders and families remain to be discovered forAmylotheca,Decaisnina,Dendrophthoe, andMuellerina. Four mistletoe genera were most prevalent on Myrtales, one on Fabales, and one on Laurales. Rosids were most often the recorded hosts (84.3% of all records). We found evidence of significant phylogenetic clustering in host use byAmyema,Amylotheca, andDecasinina. ConclusionsOur results, particularly the high prevalence on rosids, suggest that relationships of mistletoes with rainforest lineages may have been established early in the history of Australian Loranthaceae and that some lineages co‐diversified with their hosts in arid regions. 

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5. Comparisons of insect and pathogen leaf damage on early Eocene Eucalyptus (Myrtaceae) from Patagonia and extant Australasian gum trees

   https://doi.org/10.3897/phytokeys.266.166635  

   Giraldo, L Alejandro (November 2025, PhytoKeys)

   Australian forests and woodlands are dominated by the species-rich (> 700 spp.) genusEucalyptusL’Hér. (Myrtaceae). Despite this modern-day dominance, the earliest macrofossil evidence of the genus comes not from Australia, but from the early Eocene Laguna del Hunco locality in Argentinean Patagonia, consisting of abundant vegetative and reproductive material. The leaves, assigned to the fossil speciesEucalyptus frenguellianaGandolfo & Zamaloa, record a diverse suite of insect and pathogenic damage that closely matches that observed on 36 extant, rainforest-associatedEucalyptusspecies. Here, I provide detailed morphological descriptions and photographic documentation of this damage, recorded on 284E. frenguellianaleaves, together with extensive comparisons to analogous damage observed in extantEucalyptusherbarium specimens (> 10,000 sheets reviewed). From the fossil material, I describe a diverse suite of 33 insect-mediated and pathogenic damage types (DTs), including twelve types of external feeding interactions, one of piercing-and-sucking marks, five of galls, ten of mines, three of pathogenic traces, and two of oviposition scars. This elevated number of DTs, encompassing a wide range of ecological interactions, indicates thatE. frenguellianawas an important ecological resource in ancient Patagonian rainforests. Some of the fossil mines were probably created by micromoths in the families Nepticulidae and Gracillariidae, as well as flies in the family Agromyzidae. However, most of the insect and pathogenic damage observed in the fossils and their corresponding extant analogs was produced by still-unknown culprits, underscoring gaps in our knowledge ofEucalyptus-associated communities and their assembly through evolutionary time. 

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