Predicting reproductive success of insect- versus bird-pollinated scattered trees in agricultural landscapes

Scattered trees are set to be lost from agricultural landscapes within the next century without sustained effort to increase recruitment. Thus, understanding the reproductive dynamics of scattered tree populations will be critical in determining how they can contribute to population restoration. The distance between conspecifics should be a key predictor of reproductive success, as more isolated trees are expected to receive fewer pollinator visits and experience increased transfer of self-pollen during longer pollinator foraging bouts. Further, isolation effects should be greater in species with less mobile pollinators. Here we contrast the effects of plant isolation on reproductive success of two species of eucalypt "paddock trees", Eucalyptus camaldulensis and Eucalyptus leucoxylon, with insect- and bird-pollination, respectively. Seed production was not affected by tree isolation in either the insect- or bird-pollinated species and once outliers were removed, neither was there an effect on germination rate. As somatic mutations may bias outcrossing rate estimates, we initially screened our microsatellite markers for mutations but found no variation in microsatellite profiles throughout the canopy of trees. Individual outcrossing rates did not decline with increasing tree isolation in either the insect- or bird-pollinated species, though there was considerable variation in these rates at large distances, suggesting that pollination becomes unreliable with increasing tree isolation. We found that pollination distances have likely increased in tree species in agricultural landscapes, and that this may be facilitated by introduced honeybees in the case of E. camaldulensis. We therefore suggest that even isolated trees of these species produce seed of sufficient quantity and quality to contribute to population restoration

Multiplexed microsatellite markers for the genetic analysis of Eucalyptus leucoxylon (Myrtaceae) and their utility for ecological and breeding studies in other Eucalyptus species

Eucalyptus leucoxylon is a widespread woodland tree species found in southeastern Australia that has suffered from, and continues to be, threatened by the impacts of habitat clearance and degradation. Populations now consist predominantly of scattered individuals, and their conservation status is of increasing concern. We report the development and characterization of a set of eight highly polymorphic microsatellite loci for E. leucoxylon. The loci can be amplified in three PCR multiplexes and electrophoresed in a single lane, allowing rapid throughput of large numbers of samples. A total of 111 alleles were detected in 68 individuals with an average of 12.3 alleles per locus, a mean expected heterozygosity of 0.83, and a mean observed heterozygosity of 0.72. The combined probabilities of identity and probabilities of paternity exclusion allow an extremely precise level of individual identification, indicating that these microsatellite markers will be ideal for population genetic and parentage-type studies in E. leucoxylon. The markers also exhibited an average of 76% conservation within the subgenus Symphyomyrtus, to which E. leucoxylon belongs, and 53% conservation across other subgenera of Eucalyptus, demonstrating the potential of these markers in ecological and breeding studies in a wide range of Eucalyptus species

A new species of barred frog, Mixophyes (Anura: Myobatrachidae) from south-eastern Australia identified by molecular genetic analyses

Published: 2 Jun. 2023Mixophyes are large ground-dwelling myobatrachid frogs from eastern Australia and New Guinea. Several of the species found in mid-eastern and south-eastern Australia are listed as threatened, due largely to declines presumably caused by the amphibian disease chytridiomycosis. Given the wide distribution of several of these species and that their distributions cross well-known biogeographic boundaries that often correspond to deep genetic breaks or species boundaries among closely related vertebrates, we undertook a molecular genetic assessment of population structure across the range of each species to determine the presence of undescribed species. Of the four species of Mixophyes subject to molecular population genetic analyses, one, the Stuttering Frog (Mixophyes balbus), showed a level of diversity consistent with the presence of two species. Morphometric, meristic and bioacoustic analyses corroborate these distinctions, and a new species is described for the populations south of the Macleay River valley in mid-eastern New South Wales to east Gippsland in Victoria. Applying the IUCN Red List threat criteria the new species meets the conservation status assessment criteria for Endangered 2B1a,b because its extent of occupancy and area of occupancy are below the threshold value and it has declined and disappeared from the southern two thirds of its distribution over the past 30 years.Michael J Mahony, Terry Bertozzi, Jaro Guzinski, Harry B Hines and Stephen C Donnella

Molecular identification of python species: Development and validation of a novel assay for forensic investigations

Python snake species are often encountered in illegal activities and the question of species identity can be pertinent to such criminal investigations. Morphological identification of species of pythons can be confounded by many issues and molecular examination by DNA analysis can provide an alternative and objective means of identification. Our paper reports on the development and validation of a PCR primer pair that amplifies a segment of the mitochondrial cytochrome b gene that has been suggested previously as a good candidate locus for differentiating python species. We used this DNA region to perform species identification of pythons, even when the template DNA was of poor quality, as might be the case with forensic evidentiary items. Validation tests are presented to demonstrate the characteristics of the assay. Tests involved the cross-species amplification of this marker in non-target species, minimum amount of DNA template required, effects of degradation on product amplification and a blind trial to simulate a casework scenario that provided 100% correct identity. Our results demonstrate that this assay performs reliably and robustly on pythons and can be applied directly to forensic investigations where the presence of a species of python is in question

Vertebral chemistry demonstrates movement and population structure of bronze whaler

Analysing the elemental composition of calcified structures of fish, such as otoliths, can show movement patterns and population structure — essential data underlying effective fisheries management. Elasmobranch vertebrae provide an analogous, yet largely underexploited component to quantify patterns of population structure in cartilaginous fishes. We quantified multi-element vertebral profiles in bronze whaler sharks Carcharhinus brachyurus from 3 regions in South Australia using laser ablation-inductively coupled plasma mass spectrometry. We used multiple approaches to examine short- (months) and long- (lifetime, years) term perspectives of element incorporation. Boosted regression trees showed that variation in multi-element concentrations at the vertebral edge (representative of the time near capture) was explained primarily by spatial and shark length-based differences. An integrated lifetime elemental signal was similarly influenced by spatial differences and shark length. Cluster analyses of detrended elemental profiles across vertebrae indicated that movement patterns were highly individualistic, reflecting the mobile behaviour of this cosmopolitan species. Differentiation among sampling regions within South Australia suggests that current state-based management appears appropriate. However, when these findings are considered with existing telemetry and molecular genetic data on population structure for the species, it is likely that there is high connectivity throughout the species’ range, and cooperation among management jurisdictions should be explored. More broadly, using multiple approaches to element analysis and the integration of methods (such as telemetry, genetics and chemistry) that vary in their representative temporal and spatial breadths will aid in quantifying the population structure and movement behaviour of sharks.Christopher Izzo, Charlie Huveneers, Michael Drew, Corey J. A. Bradshaw, Stephen C. Donnellan, Bronwyn M. Gillander

FIGURE 9 in Revision of Litoria rothii (Anura: Pelodryadidae) from northern Australia

FIGURE 9. Photos in life of Litoria ridibunda sp. nov. from A) Wyndham, WA (Marion Anstis); B) WAM R167789, Surveyors Pool, Mitchell Plateau, WA (Paul Doughty); C) Red Cone Creek, WA (Paul Doughty); D) Channel Island Road, outer Darwin, NT (Stephen Richards); E) Ringwood, NT (Stephen Richards); F) Fogg Dam, NT (Matt Greenlees); G) Mitchell Plateau, WA (Jen Francis).Published as part of <i>Donnellan, S.C., Catullo, R.A., Rowley, J.J.L., Doughty, P., Price, L., Hines, H.B. & Richards, S.J., 2023, Revision of Litoria rothii (Anura: Pelodryadidae) from northern Australia, pp. 73-108 in Zootaxa 5352 (1)</i> on page 100, DOI: 10.11646/zootaxa.5352.1.3, <a href="http://zenodo.org/record/8406992">http://zenodo.org/record/8406992</a&gt

Phylogenetic relationships of the cuscuses (Diprotodontia: Phalangeridae) of island Southeast Asia and Melanesia based on the mitochondrial ND2 gene

The species-level systematics of the marsupial family Phalangeridae, particularly Phalanger, are poorly understood, due partly to the family’s wide distribution across Australia, New Guinea, eastern Indonesia, and surrounding islands. In order to refine the species-level systematics of Phalangeridae, and improve our understanding of their evolution, we generated 36 mitochondrial ND2 DNA sequences from multiple species and sample localities. We combined our new data with available sequences and produced the most comprehensive molecular phylogeny for Phalangeridae to date. Our analyses (1) strongly support the monophyly of the three phalangerid subfamilies (Trichosurinae, Ailuropinae, Phalangerinae); (2) reveal the need to re-examine all specimens currently identified as ‘Phalanger orientalis’; and (3) suggest the elevation of the Solomon Island P. orientalis subspecies to species level (P. breviceps Thomas, 1888). In addition, samples of P. orientalis from Timor formed a clade, consistent with an introduction by humans from a single source population. However, further research on east Indonesian P. orientalis populations will be required to test this hypothesis, resolve inconsistencies in divergence time estimates, and locate the source population and taxonomic status of the Timor P. orientalis.Shimona Kealy, Stephen C. Donnellan, Kieren J. Mitchell, Michael Herrera, Ken Aplin, Sue O'Connor and Julien Louy

FIGURE 8 in Revision of Litoria rothii (Anura: Pelodryadidae) from northern Australia

FIGURE 8. Holotype of L. ridibunda sp. nov. (NTM R36917) in life: A) latero-dorsal view (Stephen Richards), B) laterodorsal view of head (Stephen Richards), C) posterior of thigh (Stephen Richards), D) groin (Stephen Richards), E) plantar view of foot, F) palmar view of hand.Published as part of <i>Donnellan, S.C., Catullo, R.A., Rowley, J.J.L., Doughty, P., Price, L., Hines, H.B. & Richards, S.J., 2023, Revision of Litoria rothii (Anura: Pelodryadidae) from northern Australia, pp. 73-108 in Zootaxa 5352 (1)</i> on page 99, DOI: 10.11646/zootaxa.5352.1.3, <a href="http://zenodo.org/record/8406992">http://zenodo.org/record/8406992</a&gt

Revision of the water-holding frogs, Cyclorana platycephala (Anura: Hylidae), from arid Australia, including a description of a new species

The water-holding frog, Cyclorana platycephala, occurs in the Australian arid and semi-arid zones but not in the central Australian deserts. Recent inspection of morphological variation in adults and larvae suggests that the taxon comprises three regional populations: eastern, northern and western that may each represent separate species. To assess the systematic status of these populations, we documented phylogenetic relationships using mitochondrial and nuclear DNA markers, divergence in adult and larval morphology and male advertisement call. Our molecular genetic data demonstrates that the western population of C. platycephala is not the sister taxon of eastern and northern representatives of this nominate species, as the latter two are more closely related to another morphologically distinct species, C. verrucosa. Discriminant Function Analysis of 14 morphological traits in adults and 15 in larvae showed a high degree of morphological differentiation of western versus eastern/northern C. platycephala. Calls of eastern and western populations differed in duration, pulse rate, frequency and especially in amplitude modulation pattern across the call duration. We describe the western population as a new species, whose range is contained entirely within Western Australia. In addition, we redescribe Cyclorana platycephala, quantify morphological and genetic differences between the eastern and northern populations, and conclude that these data support recognition of a single species, Cyclorana platycephala, for populations found in New South Wales, the Barkly Tablelands and south-eastern Northern Territory, Queensland and South Australia.Marion Anstis, Luke C. Price, J. Dale Roberts, Sarah R. Catalano, Harry B. Hines, Paul Doughty, Stephen C. Donnella