A new brooding species of the biscuit star Tosia (Echinodermata:Asteroidea:Goniasteridae), distinguished by molecular, morphological and larval characters

2009 ◽  
Vol 23 (4) ◽  
pp. 348 ◽  
Author(s):  
Kate M. Naughton ◽  
Timothy D. O'Hara

The biscuit star Tosia australis Gray, 1840 is a well known component of the shallow rocky reef fauna of south-eastern Australia. The putative T. australis species complex was subjected to reproductive, morphometric and molecular analyses. Molecular analyses of the data from three markers (mitochondrial COI and 16S rRNA and the nuclear non-coding region ITS2) confirmed the presence of a cryptic species, the morphology of which does not agree with any of the existing nominal species. Two separate reproductive modes were observed within the complex and documented via scanning electron microscopy. T. neossia, sp. nov., described herein from south-eastern Australia, is shown to release gametes from gonopores on the actinal surface. Embryos develop first into non-feeding, non-swimming brachiolaria, and then into tripod brachiolaria before metamorphosis. No surface cilia are present at any point throughout development of T. neossia. T. australis sensu stricto is shown to release gametes from the abactinal surface. Embryos develop into non-feeding, swimming brachiolaria before metamorphosis. Whereas T. australis var. astrologorum is confirmed as synonymous with T. australis, the status of the putative Western Australian taxon T. nobilis remains unresolved.

2008 ◽  
Vol 35 (1) ◽  
pp. 8 ◽  
Author(s):  
Geoff W. Brown ◽  
Andrew F. Bennett ◽  
Joanne M. Potts

Many species of reptiles are sedentary and depend on ground-layer habitats, suggesting that they may be particularly vulnerable to landscape changes that result in isolation or degradation of native vegetation. We investigated patterns of reptile distribution and abundance in remnant woodland across the Victorian Riverina, south-eastern Australia, a bioregion highly modified (>90%) by clearing for agriculture. Reptiles were intensively surveyed by pitfall trapping and censuses at 60 sites, stratified to sample small (<30 ha) and large (>30 ha) remnants, and linear strips of roadside and streamside vegetation, across the regional environmental gradient. The recorded assemblage of 21 species was characterised by low abundance and patchy distribution of species. Reptiles were not recorded by either survey technique at 22% of sites and at a further 10% only a single individual was detected. More than half (53%) of all records were of two widespread, generalist skink species. Multivariate models showed that the distribution of reptiles is influenced by factors operating at several levels. The environmental gradient exerts a strong influence, with increasing species richness and numbers of individuals from east (moister, higher elevation) to west (drier, lower elevation). Differences existed between types of remnants, with roadside vegetation standing out as important; this probably reflects greater structural heterogeneity of ground and shrub strata than in remnants subject to grazing by stock. Although comparative historical data are lacking, we argue that there has been a region-wide decline in the status of reptiles in the Victorian Riverina involving: (1) overall population decline commensurate with loss of >90% of native vegetation; (2) disproportionate decline of grassy dry woodlands and their fauna (cf. floodplains); and (3) changes to populations and assemblages in surviving remnants due to effects of land-use on reptile habitats. Many species now occur as disjunct populations, vulnerable to changing land-use. The status of reptiles in rural Australia warrants greater attention than has been given to date. Effective conservation of this component of the biota requires better understanding of the population dynamics, habitat use and dispersal capacity of species; and a commitment to landscape restoration coupled with effective ecological monitoring.


2002 ◽  
Vol 50 (5) ◽  
pp. 439 ◽  
Author(s):  
Stephen C. Donnellan ◽  
Mark N. Hutchinson ◽  
Paula Dempsey ◽  
William S. Osborne

Allozyme electrophoresis was used to assess the taxonomic significance of colour pattern variation within and between populations of the Egernia whitii species group from 41 locations in south-eastern Australia. Analysis of the products of 39 presumed loci revealed that a minimum of three species are present in southern New South Wales among populations previously referred to Egernia whitii. Fixed allelic differences were maintained where pairs of species were sympatric. One of these three species is wide-ranging and is the one to which the name E. whitii is properly applied. The other two are more restricted ecologically and geographically and are described here as new. The three species are genetically and morphologically distinct from the other three eastern Australian members of the species group, E.�margaretae, E. modesta, and E. multiscutata. Genetic data and a review of the morphological evidence provide no support for the recognition of subspecies within either E. whitii (sensu stricto) or E. multiscutata.


1992 ◽  
Vol 43 (1) ◽  
pp. 213 ◽  
Author(s):  
JG Pepperell

Records of shark captures were extracted from the archives of 10 of the major New South Wales gamefishing clubs that operate from ports located between latitudes 33�s and 37�s. Although organized game fishing began off eastern Australia in 1936, the majority of catches were made after 1960. Data normally recorded by these clubs included common name of shark, whole weight, locality of capture, boat name and angler. Recognized single species of sharks recorded by these clubs were blue (Prionace glauca), tiger (Galeocerdo cuvier), white (Carcharodon carcharias), shortfin mako (Isurus oxyrinchus) and grey nurse (Carcharias taurus). Species identified only to generic level, and recorded by clubs, were whalers or requiem sharks (Carcharhinus spp.), hammerheads (Sphyrna spp.) and threshers (Alopias spp.). Analysis of catch records indicated that the mako shark was the most common species caught overall, although whaler sharks dominated the catch in the northern part of the study area and hammerhead sharks dominated the catch in the south. Grey nurse and white sharks were relatively rare in the southern part of the study area. Whaler sharks dominated the catch in the 1960s, and the proportions of blue and tiger sharks in the catch increased in the 1980s. Size ranges and distributions of some species also varied through time and by area. Some of the observed changes could be attributed to changed fishing practices, particularly the increasing popularity of tag-and-release and an increasing tendency to fish further from the coast. A marked decline in the number and proportion of white sharks in the catch since the 1970s gives cause for some concern regarding the status of that species off south-eastern Australia.


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