Geographic Variation in an Australian Species of Chaoborus (Diptera: Culicidae)

1983 ◽  
Vol 31 (1) ◽  
pp. 15
Author(s):  
DH Colless

Populations of an unnamed species of Chaoborus vary geographically in south-eastern Australia, along what appears to be a north-south cline. At least five characters are involved: in the adult, wing length and the colour of the style of the male coxite; in the larva, overall size, a complex character that includes relative breadth of the head, and degree of development of oesophageal molars. The dimensional characters of the larva were synthesized by means of principal component analysis; they show significant regressions on temperature. Latitudinal variation in size also occurs in the mosquitoes Anopheles annulipes and Culex vigilax, illustrating the occurrence in Culicidae of something analogous to 'Bergman's Rule' (of homoiotherms).

2008 ◽  
Vol 56 (4) ◽  
pp. 223 ◽  
Author(s):  
Murray J. Littlejohn

The male advertisement call of anuran amphibians has a major role in mate choice, and regional variation in this attribute can act as an indicator of speciation and a marker for genetic differentiation. As part of a regional study of geographic variation in the male advertisement call of Crinia signifera across south-eastern Australia and adjacent larger continental islands, samples of advertisement calls from two populations on Kangaroo Island and two populations on the adjacent Fleurieu Peninsula were compared. Four call attributes were considered: pulse number, call duration, pulse rate and dominant frequency. Pulse number is considered the most reliable for comparative purposes because it is not influenced by effective temperature or audio recording and analysis. The two island populations (central and eastern, ~24 km apart) differ significantly in pulse number, with contact but no overlap of interquartile ranges. The eastern sample differs markedly from those on the nearby Fleurieu Peninsula – which are both similar to the more distant central island sample. Geographic variation in pulse number in these four samples and 11 others from two recent publications is then interpreted in the light of land bridges and lower temperatures of the late Pleistocene and early Holocene.


PLoS ONE ◽  
2015 ◽  
Vol 10 (3) ◽  
pp. e0120975 ◽  
Author(s):  
Naomi E. Davis ◽  
David M. Forsyth ◽  
Barbara Triggs ◽  
Charlie Pascoe ◽  
Joe Benshemesh ◽  
...  

1984 ◽  
Vol 32 (2) ◽  
pp. 239 ◽  
Author(s):  
JM Dearn

The frequencies of the 3 colour pattern morphs (plain, striped and incomplete-striped) in samples of Phaulacridium vittatum (Sjost). from pasture sites in Victoria, Australia, did not conform to the pattern predicted by the latitudinal cline in morph frequencies previously described in south-eastern Australia. Data from 2 transects across pasture-forest boundaries revealed the existence of habitat associations, with forest habitats having a higher frequency of the plain morph. The proximity of some pasture populations to forests may explain some of the variation in morph frequencies observed among pasture sites. However, the frequency of the striped morph was relatively low in all the populations examined; this suggests that there are strong selective constraints on the frequency of striped individuals.


1979 ◽  
Vol 30 (2) ◽  
pp. 237 ◽  
Author(s):  
W Koste

Brachionus keikoa, sp. nov., Keratella shieli, sp. nov. (family Brachionidae Bartos, 1959), and Filinia pejleri var. grandis, var. nov. (family Filiniidae Bartos, 1959), from the River Murray at Mannum, South Australia, and Lecane ungulata var. australiensis, var. nov. (family Lecanidae Bartos, 1959), from waters associated with the Goulburn River at Alexandra, Victoria, are described and figured. B. keikoa has affinities with the angularis-caudatus species group, differing in the location of the foot-opening, the site of the lateral antennae, and in the morphology of the lorica surface. K. shieli is closely related to the quadrata species group, differing in the morphology of the caudal plate and lorica facets. L. (s.str.) ungulata var. australiensis differs from the type in the form of the anterior lorica border and in larger size. F. pejleri var. grandis has the greatest measurements in length of body and bristles of all described forms so far known from other continents. Figures of some 10 species of Brachionus and of eight species of Keratella are presented for comparative purposes.


1977 ◽  
Vol 28 (4) ◽  
pp. 403 ◽  
Author(s):  
WD Williams

Three Australian species of Paratya have been described. However, only one, P. australiensis, can be accepted. It occurs in Australia in a broad south-eastern arc, and in a wide variety of permanent inland waters (coastal streams, rivers, lakes, farm dams and ponds). In these it favours vegetated areas. Young hatch as free-floating larvae and hatching occurs mainly in early summer in southern Victoria. Females breed in their second summer. In south-eastern Australia, at least, this breeding season appears adapted to the hydrological regime of running waters.


2009 ◽  
Vol 22 (4) ◽  
pp. 296 ◽  
Author(s):  
A. S. Harvey ◽  
Wm J. Woelkerling ◽  
A. J. K. Millar

The genus Lithophyllum (Lithophylloideae, Corallinaceae, Rhodophyta) is represented by six species in south-eastern Australia L. chamberlainianum Woelkerling & Campbell, L. corallinae (Crouan & Crouan) Heydrich, L. cuneatum Keats, L. pustulatum (Lamouroux) Foslie, L. riosmenae, sp. nov., and L. stictaeforme (Areschoug in Agardh) Hauck. Four of these taxa are commonly found in Australia, whereas L. cuneatum was previously known only from Fiji and L. riosmenae is newly described. Morphological and anatomical accounts are provided, including keys, information on distribution, nomenclature and habitat in south-eastern Australia. South-eastern Australian species are primarily delimited on characters relating to tetrasporangial conceptacles and the presence/absence of a semi-endophytic habit. Ten species of Lithophyllum are now confirmed to occur in Australia and their diagnostic characters are detailed. Confirmed Australian species of Lithophyllum are primarily delimited on characters relating to tetrasporangial conceptacles, the presence/absence of a semi-endophytic habit and the growth-form. Biogeographic comparisons between south-eastern Australia and other Australian biogeographic regions are also made. Eight species of Lithophyllum are known to occur in southern Australia, three in tropical eastern Australia and three in subtropical western Australia. Southern and south-eastern Australia show major overlap, with five species occurring in both regions. L. pustulatum and L. stictaeformae are widely distributed, having been confirmed to occur in eastern tropical, western subtropical, warm temperate and cold temperate waters within Australia.


2010 ◽  
Vol 18 (04) ◽  
pp. 763-785 ◽  
Author(s):  
JUDIT K. SZABO ◽  
EUGENIO M. FEDRIANI ◽  
M. MANUELA SEGOVIA-GONZÁLEZ ◽  
LEE B. ASTHEIMER ◽  
MIKE J. HOOPER

This paper introduces a new technique in ecology to analyze spatial and temporal variability in environmental variables. By using simple statistics, we explore the relations between abiotic and biotic variables that influence animal distributions. However, spatial and temporal variability in rainfall, a key variable in ecological studies, can cause difficulties to any basic model including time evolution. The study was of a landscape scale (three million square kilometers in eastern Australia), mainly over the period of 1998–2004. We simultaneously considered qualitative spatial (soil and habitat types) and quantitative temporal (rainfall) variables in a Geographical Information System environment. In addition to some techniques commonly used in ecology, we applied a new method, Functional Principal Component Analysis, which proved to be very suitable for this case, as it explained more than 97% of the total variance of the rainfall data, providing us with substitute variables that are easier to manage and are even able to explain rainfall patterns. The main variable came from a habitat classification that showed strong correlations with rainfall values and soil types.


1977 ◽  
Vol 25 (4) ◽  
pp. 733 ◽  
Author(s):  
PG Johnston ◽  
GB Sharman

Geographic variation in potoroos (genus Potorous) from south-eastern Australia and Tasmania was investigated by electrophoretic and chromosomal techniques. Six of the 10 potoroo blood proteins examined showed electrophoretic variation and the genetic basis of three of these was established by breeding studies. Levels of genic heterozygosity were similar in Tasmanian and mainland populations. Coefficients of genetic similarity based on 10 loci indicated that potoroos from Tasmania and the Bass Strait islands are similar to each other but different from those of mainland Australia. No chromosomal variation was observed in potoroos examined from south-eastern Australia and Tasmania. Crosses between animals from these regions produced fertile offspring. It is concluded from this study and a related investigation on morphological variation that the genus Potorous should be separated into two species, P. platyops and P. tridactylus, with the further subdivision of the latter species into P.t. tridactylus from mainland Australia (including P. gilberti) and P.t. apicalis from Tasmania and the Bass Strait islands.


2007 ◽  
Vol 58 (4) ◽  
pp. 327 ◽  
Author(s):  
Michael P. Hammer ◽  
Mark Adams ◽  
Peter J. Unmack ◽  
Keith F. Walker

The smelt genus Retropinna nominally includes three small (<150 mm) freshwater fish species endemic to south-eastern Australia and New Zealand. For the two Australian species, the broad range of R. semoni (Weber) on the mainland suggests some vulnerability to isolation and genetic divergence, whereas the apparent confinement of R. tasmanica McCulloch to Tasmania is curious if, as suspected, it is anadromous. Analyses of Australian material using allozyme electrophoresis show five genetically distinct species with contiguous ranges and no evidence of genetic exchange. Three occur along the eastern seaboard (including three instances of sympatry), another in coastal and inland south-eastern Australia and Tasmania, and a fifth species in the Lake Eyre Basin. There is no indication of a simple ‘tasmanica’ v. ‘semoni’ dichotomy, but instead a complex pattern involving discrete clusters for the Upper Murray plus Darling rivers, Lower Murray, Glenelg River and Tasmanian regions, with coastal western Victorian samples having varying affinity to these groups. The overall pattern is one of deep divergences among species and strong genetic sub-structuring within and provides a strong argument for extended studies to prepare for appropriate conservation measures.


2005 ◽  
Vol 53 (4) ◽  
pp. 221 ◽  
Author(s):  
M. J. Littlejohn

The structure of recorded advertisement calls of a total of 176 males of Crinia signifera from eight localities on the south-eastern Australian mainland and Tasmania was investigated. On the basis of number of pulses per call (samples from all localities) and call duration adjusted to 13.0°C (samples from six localities), two geographic groups are recognised: (1) south-central Victoria, and (2) the extreme south-eastern mainland and Tasmania. This pattern of variation is postulated to reflect expansion of a differentiated Tasmanian stock on to the extreme south-eastern Australian mainland along the eastern sill of the Bassian Isthmus during the lower sea levels of the Late Pleistocene. Geographic variation in pulse rate (derived from number of pulses and call duration) was also considered because of its use in previous studies. The variation in dominant frequency in samples from five localities, adjusted for snout–vent length, does not conform to that for number of pulses and call duration, and is attributed to differences in demographic structure and recruitment.


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