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2.
Zootaxa ; 4990(3): 401-453, 2021 Jun 22.
Article in English | MEDLINE | ID: mdl-34186750

ABSTRACT

This revision demonstrates that an integrated taxonomic approach to classical taxonomic practice can lead to increased internal cladistic resolution within a clade, including the recognition of new taxa at all nomenclatural levels. In particular, this revision has two aims: 1) to complete an α-taxonomic revision of Seraphsidae (Stromboidea); and 2) to resolve the infrafamilial relationships within Seraphsidae using morphological cladistics. An annotated synonymy was generated for each taxon, the precedence of names determined, and revised descriptions formulated. Character sets that reflect the synapomorphies within the major subclades of Seraphsidae were coded and a cladogram generated using maximum likelihood within the tnt program with default settings. Four forms of material and evidence were used in this systematic review: 1) the type material for each taxon; 2) non-type physical material; 3) published images; and 4) literary references for specimen localities without illustration. The current morphologically-based classification of Seraphsidae was found to be sound in terms of current species delimitations. Regardless of this, the use of an integrated taxonomy improved understanding of the internal cladistic relationships within Seraphsidae, which led to higher resolution of the internal cladistic arrangements and taxonomic delimitation. Furthermore, this increased resolution is now reflected in the family nomenclature. Two new subfamilies are proposed, Seraphsinae and Pseudoterebellinae, which are used to distinguish the two clades within Seraphsidae based on form: members of Seraphsinae are involute, while members of Pseudoterebellinae are evolute. Pseudoterebellum is proposed as a new genus to show the discontinuity in the fossil record and highlight the structural differences between it and Terebellum. A new species from Jamaica, Seraphs kaindraperi, is described, being the first record from that location and that geological period and is morphologically distinct from other described taxa. This revision included Mauryna within Seraphsidae on the grounds that it provides a basal link to the Seraphsidae sister taxa Semiterebellum and Terebellopsis, all of which are currently contained within Rostellariidae, and all three clades may in time be brought together under one family. All clades have been constructed to be in compliance with both the ICZN and PhyloCode. It was not possible within the context of this revision to test the results of the α-taxonomic findings against phylogenies generated with molecular data. This was due to the high number of extinct taxa within the Seraphsidae.


Subject(s)
Gastropoda/classification , Animals , Fossils , Phylogeny
3.
Conserv Biol ; 35(3): 846-858, 2021 06.
Article in English | MEDLINE | ID: mdl-32885491

ABSTRACT

The Great Barrier Reef is an iconic ecosystem, known globally for its rich marine biodiversity that includes many thousands of tropical breeding seabirds. Despite indications of localized declines in some seabird species from as early as the mid-1990s, trends in seabird populations across the reef have never been quantified. With a long history of human impact and ongoing environmental change, seabirds are likely sentinels in this important ecosystem. Using 4 decades of monitoring data, we estimated site-specific trends for 9 seabird species from 32 islands and cays across the reef. Trends varied markedly among species and sites, but probable declines occurred at 45% of the 86 species-by-site combinations analyzed compared with increases at 14%. For 5 species, we combined site-specific trends into a multisite trend in scaled abundance, which revealed probable declines of Common Noddy (Anous stolidus), Sooty Tern (Onychoprion fuscatus), and Masked Booby (Sula dactylatra), but no long-term changes in the 2 most widely distributed species, Greater Crested Tern (Thalasseus bergii) and Brown Booby (Sula leucogaster). For Brown Booby, long-term stability largely resulted from increases at a single large colony on East Fairfax Island that offset declines at most other sites. Although growth of the Brown Booby population on East Fairfax points to the likely success of habitat restoration on the island, it also highlights a general vulnerability wherein large numbers of some species are concentrated at a small number of key sites. Identifying drivers of variation in population change across species and sites while ensuring long-term protection of key sites will be essential to securing the future of seabirds on the reef.


Tendencias en las Poblaciones de Aves Marinas Reproductoras a lo largo de la Gran Barrera de Arrecifes Resumen La Gran Barrera de Arrecife es un ecosistema icónico, conocido mundialmente por la riqueza de biodiversidad marina que incluye a miles de aves marinas tropicales en reproducción. A pesar de las indicaciones de la declinación localizada de algunas especies de aves marinas que datan desde tan temprano como mediados de la década de 1990, nunca se han cuantificado las tendencias de las poblaciones de aves marinas a lo largo del arrecife. Con una larga historia de impacto antropogénico y el cambio climático en curso, las aves marinas son los probables centinelas de este importante ecosistema. Usamos cuatro décadas de datos de monitoreo para estimar las tendencias específicas de sitio para nueve especies de aves marinas en 32 islas y cayos en todo el arrecife. Las tendencias variaron notablemente entre especies y sitios, aunque las declinaciones probables ocurrieron en 45% de las 86 combinaciones de especie por sitio analizadas en comparación con los incrementos al 14%. Combinamos las tendencias específicas de sitio para cinco especies con una tendencia multisitio con abundancia escalada. Lo anterior reveló declinaciones probables para las siguientes especies: Anous stolidus, Onychoprion fuscatus y Sula dactylatra, pero ningún cambio a largo plazo para las dos especies con mayor distribución: Thalasseus bergii y Sula leucogaster. Para Sula leucogaster, la estabilidad a largo plazo resultó principalmente de los incrementos en una gran colonia única en la isla Fairfax del Este, la cual compensó las declinaciones en casi todos los demás sitios. Aunque el crecimiento de la población de Sula leucogaster en la isla Fairfax del Este apunta hacia el éxito probable de la restauración del hábitat en la isla, también resalta una vulnerabilidad general en la que los grandes números de algunas especies están concentrados en un número reducido de sitios importantes. La identificación de los causantes de la variación en los cambios poblacionales en las especies y en los sitios mientras se asegura la protección a largo plazo de los sitios importantes será esencial para asegurar el futuro de las aves marinas del arrecife.


Subject(s)
Conservation of Natural Resources , Ecosystem , Animals , Birds , Environmental Monitoring , Humans , Islands
4.
Zootaxa ; 4555(4): 491-506, 2019 Feb 14.
Article in English | MEDLINE | ID: mdl-30790932

ABSTRACT

Here we evaluate the taxonomy of the marine gastropod genus Laevistrombus Abbott, 1960 and determine that there are five extant species within this genus, three of which occur in the southwest Pacific. Comparative analyses of this complex have been problematic due to the lack of designated type material. Therefore, we present the type material for L. canarium Linnaeus, 1758; L. taeniatus Quoy Gaimard, 1834; and L. vanikorensis Quoy Gaimard, 1834. Current taxonomy has L. vanikorensis absorbed within the L. canarium complex. L. taeniatus is generally held to be a synonym of L. turturella Röding, 1789. We demonstrate that both L. taeniatus and L. vanikorensis are distinct species and reinstate both to species level. Our revision also notes the significant variability in early teleoconch structure within the geographic range of L. vanikorensis, and highlights the need for a greater revision of Laevistrombus, given the diversity in early teleoconch morphology present in southwest Pacific species.


Subject(s)
Gastropoda , Animals , Pacific Ocean
5.
Trop Med Infect Dis ; 3(4)2018 Oct 08.
Article in English | MEDLINE | ID: mdl-30297603

ABSTRACT

The impacts of free-roaming canids (domestic and wild) on public health have long been a concern in Australian Indigenous communities. We investigated the prevalence of zoonotic helminth diseases in dogs and sympatric dingoes, and used radio telemetry to measure their spatial overlap, in an Aboriginal community in the Wet Tropics of Australia. Samples collected from dingoes and dogs showed high levels of infection with the zoonotic hookworm, Ancylostoma caninum. Dingoes were also positive for A. ceylanicum infection (11.4%), but dogs were infection free. Whipworm, Trichuris vulpis, infection was far more prevalent in necropsies of domestic dogs (78.6%) than dingoes (3.7%). Dogs were free from Dirofilaria immitis infection, while dingoes recorded 46.2% infection. Eleven dingoes and seven free-roaming domestic dogs were fitted with Global Positioning System collars and tracked over an extended period. Dingo home-ranges almost completely overlapped those of the domestic dogs. However, dingoes and dogs did not utilise the same area at the same time, and dogs may have avoided dingoes. This spatial overlap in resource use presents an opportunity for the indirect spill-over and spill-back of parasites between dogs and dingoes. Tracking and camera traps showed that the community rubbish tip and animal carcasses were areas of concentrated activity for dogs and dingoes.

6.
Ecol Evol ; 7(21): 8927-8935, 2017 11.
Article in English | MEDLINE | ID: mdl-29152188

ABSTRACT

In Australia, dingoes (Canis lupus dingo) have been implicated in the decline and extinction of a number of vertebrate species. The lowland Wet Tropics of Queensland, Australia is a biologically rich area with many species of rainforest-restricted vertebrates that could be threatened by dingoes; however, the ecological impacts of dingoes in this region are poorly understood. We determined the potential threat posed by dingoes to native vertebrates in the lowland Wet Tropics using dingo scat/stomach content and stable isotope analyses of hair from dingoes and potential prey species. Common mammals dominated dingo diets. We found no evidence of predation on threatened taxa or rainforest specialists within our study areas. The most significant prey species were northern brown bandicoots (Isoodon macrourus), canefield rats (Rattus sordidus), and agile wallabies (Macropus agilis). All are common species associated with relatively open grass/woodland habitats. Stable isotope analysis suggested that prey species sourced their nutrients primarily from open habitats and that prey choice, as identified by scat/stomach analysis alone, was a poor indicator of primary foraging habitats. In general, we find that prey use by dingoes in the lowland Wet Tropics does not pose a major threat to native and/or threatened fauna, including rainforest specialists. In fact, our results suggest that dingo predation on "pest" species may represent an important ecological service that outweighs potential biodiversity threats. A more targeted approach to managing wild canids is needed if the ecosystem services they provide in these contested landscapes are to be maintained, while simultaneously avoiding negative conservation or economic impacts.

7.
Sci Rep ; 7(1): 4458, 2017 06 30.
Article in English | MEDLINE | ID: mdl-28667257

ABSTRACT

Terrestrial plants use an array of animals as vectors for dispersal, however little is known of biotic dispersal of marine angiosperms such as seagrasses. Our study in the Great Barrier Reef confirms for the first time that dugongs (Dugong dugon) and green sea turtles (Chelonia mydas) assist seagrass dispersal. We demonstrate that these marine mega-herbivores consume and pass in faecal matter viable seeds for at least three seagrass species (Zostera muelleri, Halodule uninervis and Halophila decipiens). One to two seagrass seeds per g DW of faecal matter were found during the peak of the seagrass reproductive season (September to December), with viability on excretion of 9.13% ± 4.61% (SE). Using population estimates for these mega-herbivores, and data on digestion time (hrs), average daily movement (km h) and numbers of viable seagrass seeds excreted (per g DW), we calculated potential seagrass seed dispersal distances. Dugongs and green sea turtle populations within this region can disperse >500,000 viable seagrass seeds daily, with a maximum dispersal distance of approximately 650 km. Biotic dispersal of tropical seagrass seeds by dugongs and green sea turtles provides a large-scale mechanism that enhances connectivity among seagrass meadows, and aids in resilience and recovery of these coastal habitats.


Subject(s)
Aquatic Organisms , Herbivory , Magnoliopsida , Seed Dispersal , Seeds , Animals , Dugong , Ecosystem , Turtles
8.
One Health ; 3: 66-69, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28616506

ABSTRACT

Ancylostoma ceylanicum is the common hookworm of domestic dogs and cats throughout Asia, and is an emerging but little understood public health risk in tropical northern Australia. We investigated the prevalence of A. ceylanicum in soil and free-ranging domestic dogs at six rainforest locations in Far North Queensland that are Indigenous Australian communities and popular tourist attractions within the Wet Tropics World Heritage Area. By combining PCR-based techniques with traditional methods of hookworm species identification, we found the prevalence of hookworm in Indigenous community dogs was high (96.3% and 91.9% from necropsy and faecal samples, respectively). The majority of these infections were A. caninum. We also observed, for the first time, the presence of A. ceylanicum infection in domestic dogs (21.7%) and soil (55.6%) in an Indigenous community. A. ceylanicum was present in soil samples from two out of the three popular tourist locations sampled. Our results contribute to the understanding of dogs as a public health risk to Indigenous communities and tourists in the Wet Tropics. Dog health needs to be more fully addressed as part of the Australian Government's commitments to "closing the gap" in chronic disease between Indigenous and other Australians, and encouraging tourism in similar locations.

9.
PeerJ ; 4: e2194, 2016.
Article in English | MEDLINE | ID: mdl-27441123

ABSTRACT

Dugongs (Dugong dugon) are listed as vulnerable to extinction due to rapid population reductions caused in part by loss of seagrass feeding meadows. Understanding dugong feeding behaviour in tropical Australia, where the majority of dugongs live, will assist conservation strategies. We examined whether feeding patterns in intertidal seagrass meadows in tropical north-eastern Australia were related to seagrass biomass, species composition and/or nitrogen content. The total biomass of each seagrass species removed by feeding dugongs was measured and compared to its relative availability. Nitrogen concentrations were also determined for each seagrass species present at the sites. Dugongs consumed seagrass species in proportion to their availability, with biomass being the primary determining factor. Species composition and/or nitrogen content influenced consumption to a lesser degree. Conservation plans focused on protecting high biomass intertidal seagrass meadows are likely to be most effective at ensuring the survival of dugong in tropical north-eastern Australia.

10.
Vet Parasitol ; 215: 6-10, 2016 Jan 15.
Article in English | MEDLINE | ID: mdl-26790730

ABSTRACT

Heartworm (Dirofilaria immitis) is a parasitic nematode responsible for canine and feline cardiopulmonary dirofilariasis and human zoonotic filariosis in both tropical and temperate regions throughout the world. Importantly, this study in the Wet Tropics of Far North Queensland found D. immitis remains at high prevalence (72.7%) in wild dingoes in low density housing areas in Australia. This prevalence is equivalent to the highest levels seen in wild dogs in Australia and represents an ongoing risk to domestic dogs, cats and humans. In contrast, in higher density residential areas prevalence was significantly lower (16.7%, p=0.001). It is possible that chemotherapeutic heartworm (HW) prevention in domestic dogs in these higher density housing areas is helping to control infection in the resident dingo population. Five dingoes killed in council control operations around Atherton, a non-endemic HW region in the Wet Tropics, were all negative for HW likely due to the colder climate of the region restricting transmission of the disease. This survey highlights the importance of dingoes as reservoir hosts of HW disease and that the subsequent risk of infection to companion animals and humans depends on local factors such as housing density, possibly linked to chemotherapeutic HW control in domestic dogs and climate. Our findings show that veterinary clinicians need to ensure that pet owners are aware of HW disease and do not become complacent about HW chemoprohylaxis in areas which support dingo populations.


Subject(s)
Dirofilaria immitis/isolation & purification , Dirofilariasis/parasitology , Disease Reservoirs/veterinary , Dog Diseases/parasitology , Animals , Antigens, Helminth , Australia/epidemiology , Dirofilariasis/epidemiology , Dog Diseases/epidemiology , Dogs , Female , Male
11.
Proc Biol Sci ; 281(1786)2014 Jul 07.
Article in English | MEDLINE | ID: mdl-24850919

ABSTRACT

Humpback whales (Megaptera novaeangliae) annually undertake the longest migrations between seasonal feeding and breeding grounds of any mammal. Despite this dispersal potential, discontinuous seasonal distributions and migratory patterns suggest that humpbacks form discrete regional populations within each ocean. To better understand the worldwide population history of humpbacks, and the interplay of this species with the oceanic environment through geological time, we assembled mitochondrial DNA control region sequences representing approximately 2700 individuals (465 bp, 219 haplotypes) and eight nuclear intronic sequences representing approximately 70 individuals (3700 bp, 140 alleles) from the North Pacific, North Atlantic and Southern Hemisphere. Bayesian divergence time reconstructions date the origin of humpback mtDNA lineages to the Pleistocene (880 ka, 95% posterior intervals 550-1320 ka) and estimate radiation of current Northern Hemisphere lineages between 50 and 200 ka, indicating colonization of the northern oceans prior to the Last Glacial Maximum. Coalescent analyses reveal restricted gene flow between ocean basins, with long-term migration rates (individual migrants per generation) of less than 3.3 for mtDNA and less than 2 for nuclear genomic DNA. Genetic evidence suggests that humpbacks in the North Pacific, North Atlantic and Southern Hemisphere are on independent evolutionary trajectories, supporting taxonomic revision of M. novaeangliae to three subspecies.


Subject(s)
Actins/genetics , Genetic Variation , Humpback Whale/genetics , Animals , Bayes Theorem , Cell Nucleus/genetics , DNA, Mitochondrial/genetics , Evolution, Molecular , Haplotypes , Molecular Sequence Data , Oceans and Seas , Phylogeny , Sequence Analysis, DNA
12.
Evol Appl ; 6(4): 660-72, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23789032

ABSTRACT

The use of a multidisciplinary approach is becoming increasingly important when developing management strategies that mitigate the economic and biological costs associated with invasive pests. A framework of simulated dispersal is combined with life-history information and analyses of population genetic structure to investigate the invasion dynamics of a plant disease vector, the island sugarcane planthopper (Eumetopina flavipes), through an archipelago of significant Australian quarantine concern. Analysis of eight microsatellite loci from 648 individuals suggests that frequent, wind-assisted immigration from multiple sources in Papua New Guinea contributes significantly to repeated colonization of far northern islands. However, intermittent wind-assisted immigration better explains patterns of genetic diversity and structure in the southern islands and on the tip of mainland Australia. Significant population structuring associated with the presence of clusters of highly related individuals results from breeding in-situ following colonization, with little postestablishment movement. Results also suggest that less important secondary movements occur between islands; these appear to be human mediated and restricted by quarantine zones. Control of the planthopper may be very difficult on islands close to Papua New Guinea given the apparent propensity for multiple invasion, but may be achievable further south where local populations appear highly independent and isolated.

13.
Mycologia ; 104(5): 1008-19, 2012.
Article in English | MEDLINE | ID: mdl-22505434

ABSTRACT

Across three tropical Australian sclerophyll forest types, site-specific environmental variables could explain the distribution of both quantity (abundance and biomass) and richness (genus and species) of hypogeous fungi sporocarps. Quantity was significantly higher in the Allocasuarina forest sites that had high soil nitrogen but low phosphorous. Three genera of hypogeous fungi were found exclusively in Allocasuarina forest sites including Gummiglobus, Labyrinthomyces and Octaviania, as were some species of Castoreum, Chondrogaster, Endogone, Hysterangium and Russula. However, the forest types did not all group according to site-scale variables and subsequently the taxonomic assemblages were not significantly different between the three forest types. At site scale, significant negative relationships were found between phosphorous concentration and the quantity of hypogeous fungi sporocarps. Using a multivariate information theoretic approach, there were other more plausible models to explain the patterns of sporocarp richness. Both the mean number of fungal genera and species increased with the number of Allocasuarina stems, at the same time decreasing with the number of Eucalyptus stems. The optimal conditions for promoting hypogeous fungi sporocarp quantity and sporocarp richness appear to be related to the presence and abundance of Allocasuarina (Casuarinaceae) host trees. Allocasuarina tree species may have a higher host receptivity for ectomycorrhizal hypogeous fungi species that provide an important food resource for Australian mycophagous animals.


Subject(s)
Eucalyptus/microbiology , Fungi/classification , Fungi/isolation & purification , Trees/microbiology , Australia , Biodiversity , Biomass , Fruiting Bodies, Fungal/metabolism , Fungi/metabolism , Nitrogen/metabolism , Phosphorus/metabolism , Soil , Spores/metabolism , Tropical Climate
14.
PLoS One ; 5(7): e11891, 2010 Jul 29.
Article in English | MEDLINE | ID: mdl-20686693

ABSTRACT

Behavioral and/or developmental plasticity is crucial for resisting the impacts of environmental stressors. We investigated the plasticity of adult foraging behavior and chick development in an offshore foraging seabird, the black noddy (Anous minutus), during two breeding seasons. The first season had anomalously high sea-surface temperatures and 'low' prey availability, while the second was a season of below average sea-surface temperatures and 'normal' food availability. During the second season, supplementary feeding of chicks was used to manipulate offspring nutritional status in order to mimic conditions of high prey availability. When sea-surface temperatures were hotter than average, provisioning rates were significantly and negatively impacted at the day-to-day scale. Adults fed chicks during this low-food season smaller meals but at the same rate as chicks in the unfed treatment the following season. Supplementary feeding of chicks during the second season also resulted in delivery of smaller meals by adults, but did not influence feeding rate. Chick begging and parental responses to cessation of food supplementation suggested smaller meals fed to artificially supplemented chicks resulted from a decrease in chick demands associated with satiation, rather than adult behavioral responses to chick condition. During periods of low prey abundance, chicks maintained structural growth while sacrificing body condition and were unable to take advantage of periods of high prey abundance by increasing growth rates. These results suggest that this species expresses limited plasticity in provisioning behavior and offspring development. Consequently, responses to future changes in sea-surface temperature and other environmental variation may be limited.


Subject(s)
Charadriiformes/physiology , Feeding Behavior/physiology , Temperature , Animals
15.
Ecology ; 90(5): 1175-83, 2009 May.
Article in English | MEDLINE | ID: mdl-19537539

ABSTRACT

Intense El Niño events severely impact seabird populations, often months in advance of peak temperature anomalies. The trophic mechanisms responsible for these impacts are unknown but are assumed to operate at seasonal scales and to be linked to ocean productivity changes. Precursors to El Niño events include changes in both sea-surface temperature and the depth of the 20 degrees C thermocline. Foraging piscivorous seabirds are known to be sensitive to both thermocline depth and sea-surface temperature change, but the potential influence of these phenomena on breeding dynamics is unknown. Using 18 years of data on three seabirds of the western tropical Pacific, we show that pelagic seabird breeding participation is directly and independently related to changes in both surface chlorophyll concentration and thermocline depth that occur well in advance of El Niño generated sea-surface temperature anomalies. In contrast, breeding in an inshore foraging species is not correlated with any environmental/biological parameters investigated. These findings demonstrate that El Niño related phenomena do not affect seabird prey dynamics solely via productivity shifts at seasonal scales, nor in similar ways across different seabird foraging guilds. Our results also suggest that population declines observed in the western tropical Pacific may be directly related to the frequency and intensity of El Niño anomalies over the study period.


Subject(s)
Charadriiformes/physiology , Animals , Pacific Ocean , Population Dynamics , Time , Tropical Climate , Weather
16.
Virus Res ; 141(2): 247-57, 2009 May.
Article in English | MEDLINE | ID: mdl-19428738

ABSTRACT

The island sugarcane planthopper, Eumetopina flavipes Muir, is the only known vector for Ramu stunt disease of sugarcane. This study examined the relationship between host plant distribution and abundance, and E. flavipes distribution, abundance and levels of population connectivity in Papua New Guinea (PNG), the Torres Strait (TS) and northern peninsula area (NPA) of Australia, as a first step in establishing E. flavipes invasion potential through the TS/NPA. Results show that E. flavipes utilises a wide range of Saccharum host species in PNG and that the occupation rates and abundances differed significantly among host types. For hosts in common, the proportion of plants occupied in PNG was significantly greater than in TS/NPA. This is likely the result of greater overall host density and connectivity in PNG. E. flavipes abundance per plant did not differ significantly between the two regions suggesting a possible plant-specific abundance and/or dispersal threshold independent of location. Whilst E. flavipes presence and persistence was highly variable at some TS/NPA locations, large and stable infestations occurred down the western edge of the TS archipelago. These populations appear to link PNG to the NPA and offer a potential incursion route for Ramu stunt disease. The stability of these populations appears to be associated with the availability and persistence of host material, which in turn is significantly affected by variation in cultivation practices. In the TS/NPA, implementation of pre-emptive management of E. flavipes via cultivation techniques, such as simultaneous tip-pruning, may be an effective means of control for the pest, and would be simpler and preferable to the direct management of Ramu stunt disease should it be detected in the TS/NPA.


Subject(s)
Hemiptera/physiology , Plant Diseases/virology , Saccharum/virology , Animals , Australia , Papua New Guinea , Population Density , Population Dynamics
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