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\"This book is the first complete pictorial atlas of the world's ray fauna. It also provides general identifying features and distributional information about this iconic, but surprisingly poorly known, group of fishes\"-- Introduction.

The distributions of 390 taxa of benthic macroinvertebrates collected in forty-eight estuaries and 101 fish species collected in seventy-five Tasmanian estuaries were related to geographical and environmental variables. Distribution patterns for the two taxonomic groups were largely congruent at both between- and within-estuary scales. Faunal composition and the number of species collected at a site were primarily related to site salinity, the biomass of seagrass and tidal range. At the broader estuary scale, the distributions of macroinvertebrate and fish assemblages were primarily correlated with the presence of an entrance bar. Species richness varied with geographical location for both macrofauna and fishes, with highest numbers of species occurring in the Furneaux Group, north-eastern Tasmania and south-eastern Tasmania. These patterns primarily reflected differences in estuary type between regions rather than concentrations of locally endemic species. Although the majority of species collected during the study were marine vagrants, they constituted a very low proportion of total animal densities within estuaries. Only four species considered exotic to Tasmania were identifed. Nearly all species recorded from Tasmanian estuaries occurred widely within the state and have also been recorded in south-eastern Australia. Only 1% of estuarine fish species and < 5% of invertebrate species were considered endemic to the state. The generally wide ranges of species around Tasmania were complicated by (i) the absence of most species from the west coast (ii) a small (< 10%) component of species that occurred only in the north-east and Furneaux Group (eastern Bass Strait), and (iii) a few species (< 5%) restricted to other regions. The low number of species recorded from estuaries along the western Tasmanian coast reflected extremely low faunal biomass in that area. This depression in biomass on the west coast was attributed to unusually low concentrations of dissolved nutrients in rivers and dark tannin-stained waters which greatly restricted algal photosynthesis and primary production.

Aim: South-eastern Australia is a climate change hotspot with well-documented recent changes in its physical marine environment. The impact on and temporal responses of the biota to change are less well understood, but appear to be due to influences of climate, as well as the non-climate related past and continuing human impacts. We attempt to resolve the agents of change by examining major temporal and distributional shifts in the fish fauna and making a tentative attribution of causal factors. Location: Temperate seas of south-eastern Australia. Methods: Mixed data sources synthesized from published accounts, scientific surveys, spearfishing and angling competitions, commercial catches and underwater photographic records, from the 'late 1800s' to the ' present', were examined to determine shifts in coastal fish distributions. Results: Forty-five species, representing 27 families (about 30% of the inshore fish families occurring in the region), exhibited major distributional shifts thought to be climate related. These are distributed across the following categories: species previously rare or unlisted (12), with expanded ranges (23) and/or abundance increases (30), expanded populations in south-eastern Tasmania (16) and extralimital vagrants (4). Another 9 species, representing 7 families, experienced longerterm changes (since the 1800s) probably due to anthropogenic factors, such as habitat alteration and fishing pressure: species now extinct locally (3), recovering (3), threatened (2) or with remnant populations (1). One species is a temporary resident periodically recruited from New Zealand. Of fishes exhibiting an obvious poleward movement, most are reef dwellers from three Australian biogeographic categories: widespread southern, western warm temperate (Flindersian) or eastern warm temperate (Peronian) species. Main conclusions: Some of the region's largest predatory reef fishes have become extinct in Tasmanian seas since the ' late 1800s', most likely as a result of poor fishing practices. In more recent times, there have been major changes in the distribution patterns of Tasmanian fishes that correspond to dramatic warming observed in the local marine environment.

Members of the genus Brevitrygon are small, locally abundant tropical stingrays (family Dasyatidae) occurring in soft sedimentary habitats of inner continental shelves of the Indo-West Pacific from the Red Sea to Indonesia. Formerly members of the genus Himantura, whose members lack dorsal and ventral skin folds on the tail (typical of most dasyatid genera), folds are present or rudimentary in some Brevitrygon. Important to artisanal fisheries and known to consist of at least five species, these fishes are possibly the most frequently misidentified of all stingrays. Most were inadequately described in the 19th century, and they are often taxonomically confused due to morphological similarity, ontogenetic variability, and sexual dimorphism. Their nomenclatural history is complex with four of the known species represented within the type series of one species, B. walga (Müller & Henle). Also, the type of the species with which B. walga is most often confused, B. imbricata (Bloch & Schneider) from off southern India and Sri Lanka, is in very poor condition. A lectotype has been designated for B. walga (confined to the Bay of Bengal). The genus also contains B. heterura (Bleeker) from the Indo-Malay Archipelago, B. javaensis (Last & White) from off southern Indonesia, and a new species, B. manjajiae sp. nov., from the western Indian Ocean. The former species are redescribed and redefined based largely on a combination of morphometrics, tail morphology, squamation, and molecular data. Molecular divergences were detected within lineages of B. heterura, B. walga and B. manjajiae sp. nov., requiring further investigation.

The first survey of the continental-slope demersal fish fauna off the west coast of Australia — the region between latitudes 20 to 35° S in depths from ~200 to 1500 m — was undertaken in 1991. Most species were caught rarely and only 14 species were represented by >1% of individuals in the total catch. Collectively, the catches were dominated numerically by the Acropomatidae and Chlorophthalmidae at shelf-break and upper slope depths (~200 to 600 m), and the Macrouridae, Bathygadidae, Synaphobranchidae, Alepocephalidae and Oreosomatidae at greater depths. Overall, the Macrouridae was both the most abundant and most species-rich family. The fauna appears to be richer (388 species from 109 families) than the slope faunas of the more intensively sampled North Atlantic and northern Pacific; its richness may be attributable to the overlap of ancient and extensive Indo-West Pacific and temperate Australasian faunas that extend from shelf to mid-slope depths. These faunas are maintained in the region by a variety of near-surface and intermediate-depth ocean currents that bathe the western slope. Seven distinct fish community types were defined by bathymetric and latitudinal boundaries: a northern and a southern shelf-break community; 2 depth-stratified communities on the upper-slope, and 3 communities defined by depth and latitude on the mid-slope. Ecotones between these communities at the 250 to 350 m and 700 to 800 m depth intervals coincide, respectively, with the lower limits of the near-surface Leeuwin Current and the upper extent of Antarctic Intermediate Water. The composition of the mid-slope fauna in the southern part of the study area suggests it is part of a wide-ranging Australasian mid-slope community shared with the Great Australian Bight, southeastern Australia and New Zealand. There is progressive replacement by a northern fauna at all depths as latitude decreases along the west coast. The western slope fauna is characterised by low density as well as high diversity. Fish density was estimated to be several times lower than on the continental slope off southeastern Australia, and also lower than North Atlantic and northern Pacific slope regions. Low density is likely to be related to low overlying productivity due to the absence of upwelling associated with the near-surface, southward-flowing Leeuwin Current. Low overlying productivity also appears to be linked to the ecological composition of the demersal fauna; it is characterised by many relatively small, benthic species, non-vertically migrating species, and a lack of aggregated large commercial fishes.

Aim To develop a comparative phylogeographic framework to understand the origins, evolution, taxonomic richness, and distribution of Australian demersal fish endemics in the context of the Indo‐West Pacific (IWP). Location Southern Australia and the IWP. Taxon Platycephalidae (flathead fishes). Methods Nuclear and mitochondrial phylogenies of flathead fishes were inferred from 46 of 85 nominal species, and 14 additional cryptic species‐level lineages, representing 17 of the 18 genera. Molecular clocks and habitat trait reconstructions were used to infer the palaeoclimatic and geological events responsible for shaping the evolution and diversification of the group. Results The family Platycephalidae comprises two sister subfamilies; Platycephalinae and Onigociinae, which diverged in the Eocene into predominantly temperate and tropical assemblages respectively. The basal platycephalin taxa are confined to southern Australia with the most derived groups in the tropics, following a high‐ to low‐latitudinal evolutionary trajectory. In contrast, the onigociins are predominantly associated with the tropics, and have diversified across the region since the early Miocene with very few introductions into temperate Australia. Main conclusions Platycephalinae and Onigociinae show contrasting evolutionary scenarios. Platycephalins have a temperate to tropical evolutionary trajectory consistent with their arrival into the region via tectonic rafting and subsequent dispersal. This dispersal was likely facilitated by formation of shallow‐water environments along the Sunda Arc margin following collision of the Australian and Eurasian Plates. In contrast, the Onigociinae has likely maintained a tropical presence across the IWP since the Eocene and has experienced higher diversification rates leading to circa three times the species diversity found in the Platycephalinae. Rounds of dispersal and allopatric speciation have subsequently played out across both low and high latitudes with both subfamilies harbouring cryptic species‐level lineages. This work provides an explicit working hypothesis for exploring origins and diversification in other demersal fishes endemic to the Australian continent.

Two hundred and seven species of fish, mostly Australian marine fish, were sequenced (barcoded) for a 655 bp region of the mitochondrial cytochrome oxidase subunit I gene (cox1). Most species were represented by multiple specimens, and 754 sequences were generated. The GC content of the 143 species of teleosts was higher than the 61 species of sharks and rays (47.1% versus 42.2%), largely due to a higher GC content of codon position 3 in the former (41.1% versus 29.9%). Rays had higher GC than sharks (44.7% versus 41.0%), again largely due to higher GC in the 3rd codon position in the former (36.3% versus 26.8%). Average within-species, genus, family, order and class Kimura two parameter (K2P) distances were 0.39%, 9.93%, 15.46%, 22.18% and 23.27%, respectively. All species could be differentiated by their cox1 sequence, although single individuals of each of two species had haplotypes characteristic of a congener. Although DNA barcoding aims to develop species identification systems, some phylogenetic signal was apparent in the data. In the neighbour-joining tree for all 754 sequences, four major clusters were apparent: chimaerids, rays, sharks and teleosts. Species within genera invariably clustered, and generally so did genera within families. Three taxonomic groups-dogfishes of the genus Squalus, flatheads of the family Platycephalidae, and tunas of the genus Thunnus-were examined more closely. The clades revealed after bootstrapping generally corresponded well with expectations. Individuals from operational taxonomic units designated as Squalus species B through F formed individual clades, supporting morphological evidence for each of these being separate species. We conclude that cox1 sequencing, or 'barcoding', can be used to identify fish species.

A new species of eagle ray, Aetomylaeus caeruleofasciatus sp. nov., is described based on specimens collected in northern Australia and southern Papua New Guinea. The new species is very closely related to Aetomylaeus nichofii and was previously considered to be conspecific with this species. The new species and A. nichofii differ from their congeners in having a dorsal pattern of seven or eight transverse pale blue bands. As with other eagle ray species, morphological characteristics which distinguish the closely related species were largely obscured by intraspecific variation. The clearest morphological differences were apparent when comparing adult males to adult males and adult females to adult females, e.g. disc longer in adult female A. caeruleofasciatus compared to adult female A. nichofii. The two species also differ in the number of pelvic radials in both females and males and show subtle colour differences. A neotype is also allocated for A. nichofii.