Systematics of the Australian species of Dictyopteris (Dictyotales, Phaeophyceae)

2000 ◽  
Vol 13 (2) ◽  
pp. 283 ◽  
Author(s):  
J. A. Phillips

Eleven species of Dictyopteris are recognised for Australia. The tropical species D. australis (Sonder) Askenasy, D. deliculata Lamouroux, D. plagiogramma (Montagne) Vickers, D. repens (Okamura) Børgesen, D. serrata (Areschoug) Hoyt and D. woodwardia (R.Brown ex Turner) C.Agardh are recorded for warmer coasts, although isolated populations of D. australis occur in the Gulfs region of South Australia. Dictyopteris acrostichoides (J.Agardh) Bornet and D. crassinervia (Zanardini) Schmidt are endemic to eastern Australia, with D. acrostichoides also extending to the eastern end of the southern coast. Dictyopteris gracilis Womersley and D. muelleri (Sonder) Reinbold occur on temperate southwestern and southern coasts. The west coast species Dictyopteris secundispiralis J.A.Phillips sp. nov. is described, and D. nigricans Womersley is reduced to a taxonomic synonym ofD. muelleri. Detailed comparative studies undertaken on these species have identified several new taxonomically-informative characters useful for generic circumscription and species discrimination. Thallus branches which have a cortical layer composed of large cuboidal cells and reproductive organs scattered in fertile zones are additional characters which characterise the genus. Australian species of Dictyopteris are now well defined by differences in several distinctive vegetative and reproductive characters such as thallus morphology, blade cell layer number, structure of the thallus apex, presence of marginal teeth and lateral veins, distribution and structure of hair bundles, sporangia, oogonia and antheridial sori.

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.


1992 ◽  
Vol 5 (6) ◽  
pp. 657 ◽  
Author(s):  
JA Phillips

Eight species of Dilophus are recognised for Australia. Detailed descriptions are given for five species, D. fastigiatus, D. gunnianus, D. intermedius, D. marginatus and D. robustus. D. moniliformis and D. crinitus from Western Australia and D. decumbens from subantarctic Macquarie I. remain poorly known. Sporophytes and gametophytes are reported for the five species providing first records of sporophytes of D. robustus, female gametophytes of D. intermedius, and both male and female gametophytes of D. robustus and D. marginatus. The arrangement and structure of sporangia and gametangia have been intensively studied and many reproductive characters not previously used in species discrimination have been incorporated into species' descriptions and used to develop species' concepts. Species are delimited on the following combination of characters: arrangement, size and structure of sporangia, arrangement and structure of gametangia, and the number of medullary cell layers.


2007 ◽  
Vol 29 (2) ◽  
pp. 191 ◽  
Author(s):  
A.J.L. Pestell ◽  
S.J.B. Cooper ◽  
K. Saint ◽  
S. Petit

Cercartetus concinnus Gould (Marsupialia: Burramyidae) has a spatially disjunct distribution, with a broad stretch of saltbush on the Nullarbor Plain forming an apparent barrier between the population: one in southern Western Australia, and another in south-eastern Australia, encompassing South Australia, Victoria, and New South Wales. This disjunct distribution and slight differences in morphology between western and eastern populations have led to conjecture about the taxonomy of this species. This study assessed the taxonomic status of C. concinnus across southern Australia. Analyses using the mitochondrial (mtDNA) ND4 gene showed little phylogeographic structure throughout the wide range of C. concinnus in southern Australia; closely related haplotypes (~0.1% sequence divergence) had a wide distribution from Western Australia to South Australia, suggesting recent genetic connectivity. These data indicate that C. concinnus populations represent a single taxonomic unit (Evolutionarily Significant Unit) throughout the geographic range. Further research is required to assess the impact of recent population fragmentation and whether an erosion of genetic variation in isolated populations has occurred.


Botany ◽  
2010 ◽  
Vol 88 (7) ◽  
pp. 639-667 ◽  
Author(s):  
Gary W. Saunders ◽  
Brian McDonald

The DNA barcode (COI-5P) was used to investigate cryptic diversity among Rhodymenia spp. in southern Australia. Whereas eight species are currently recognized, we uncovered ca. 20 genetic species groups, phylogenetically assigned to four genera in two families. Procumbent specimens with molecular and anatomical signatures of the Fryeellaceae are assigned to Pseudohalopeltis tasmanensis gen. et sp. nov. Collections from Lord Howe Island recorded in the field as Rhodymenia / Fauchea sp. are assigned to the poorly known genus Microphyllum as Microphyllum robustum sp. nov. A cluster of species with distinct molecular and anatomical attributes is included in a resurrected Halopeltis J.G. Agardh, including Halopeltis australis (J. Agardh) comb. nov. (type species); Halopeltis austrina (Womersley) comb. nov.; Halopeltis cuneata (Harvey) comb. nov. [including Rhodymenia halymenioides (J. Agardh) Womersley]; Halopeltis gracilis sp. nov.; Halopeltis prostrata sp. nov.; and Halopeltis verrucosa (Womersley) comb. nov. Four additional species of Halopeltis from Lord Howe Island (LH1, LH2), Tasmania (TAS), and Western Australia are not characterized further. For Rhodymenia sensu stricto, similar levels of cryptic diversity were noted. Samples tentatively field-identified as “ Rhodymenia sonderi ,” but having affiliations to Rhodymenia rather than Halopeltis, are referred to Rhodymenia novahollandica sp. nov. Collections field-identified as R. obtusa are genetically distinct from that species and are assigned to Rhodymenia wilsonis (Sonder) comb. nov. Two highly divergent species currently identified as Rhodymenia leptophylla (LH from Lord Howe Island; TAS from Tasmania), as well as two additional cryptic previously unnamed taxa from South Australia (SA) and Victoria (VIC), are not characterized further.


1998 ◽  
Vol 46 (6) ◽  
pp. 671 ◽  
Author(s):  
G. J. Starr ◽  
S. M. Carthew

Fragmentation of the landscape by human activity has created small, isolated plant populations. Hakea carinata F. Muell. ex Meissner, a sclerophyllous shrub, is common in isolated fragments of vegetation in South Australia. This study investigated whether habitat fragmentation has caused restrictions to gene flow between populations. Gene diversity (HT = 0.317) is average for similar species but little is held within populations (HS = 0.168) and 46.9% of gene diversity is accounted for between populations. Estimates of gene flow are NM = 0.270 (based on FST) and NM = 0.129 (based on private alleles). Populations are substantially selfing (t = 0.111). Small isolated populations appears to be a long-term evolutionary condition in this species rather than a consequence of habitat fragmentation; however, population extinctions are occurring. Conservation will require the reservation of many populations to represent the genetic variation present in the species.


2004 ◽  
Vol 55 (2) ◽  
pp. 165 ◽  
Author(s):  
Timothy J. Page ◽  
Suman Sharma ◽  
Jane M. Hughes

The freshwater fish, Rhadinocentrus ornatus Regan, 1914, has a patchy distribution through coastal drainages of Queensland and New South Wales, eastern Australia. Isolated populations of R. ornatus are found on several islands, as well as in a disjunct northern population 350 km from its nearest conspecific population. Deoxyribonucleic acid was extracted and sequenced for the mitochondrial ATPase gene to describe the geographic and genetic subdivision within the species. Four major clades were identified. These clades diverged between two and seven million years ago and so represent long-term divisions and possible units of conservation. There are conservation implications in that the narrow and localised distribution of R. ornatus overlaps with an area of large-scale land clearing, high human population and threats from introduced exotic fish. A particularly high centre of Rhadinocentrus diversity in the Tin Can Bay area of Queensland presents some interesting questions about the evolution of the genus Rhadinocentrus.


Zootaxa ◽  
2021 ◽  
Vol 4965 (3) ◽  
pp. 515-528
Author(s):  
MARCO CURINI-GALLETTI ◽  
ERNEST R. SCHOCKAERT

The genus Tajikacelis n. gen. is introduced for species of Archimonocelididae (Proseriata) characterized by the lack of atrial spines in the copulatory organ and by the opening of the seminal vesicles into the prostate vesicle at its ventral side. Six new species from the Pacific Ocean are ascribed to the new genus; they may be distinguished by features of the genital systems and the morphology of their copulatory stylets. T. tajikai n. sp. (type species of the new genus) and T. macrostomoides n. sp., both from eastern Australia, have a long tubular stylet. In T. macrostomoides n. sp., the stylet is more curved, bending to 180°, and has a narrower basis compared to that of T. tajikai n. sp. In T. artoisi n. sp., from Hawai’i, and T. nematoplanoides n. sp., from South Australia, the stylet is shaped as a truncated cone, with a broad, oblique proximal opening and a very short tubular part. T. artoisi n. sp. is distinct for the much stronger thickening of the dorsal side of the stylet, and for the different shape of the proximal opening. In T. acuta n. sp. and T. truncata n. sp., from West Panama, the tubular stylet is comparatively short; the two species differ for the shape of the distal opening, produced into a sharp spike in T. acuta n. sp., and square-ended in T. truncata n. sp.. Two species previously described in the genus Archimonocelis are transferred to Tajikacelis n. gen.: T. itoi Tajika, 1981 from Japan and T. keke Martens and Curini-Galletti, 1989 from Sulawesi (Indonesia). The taxonomic position of the problematic Archimonocelis glabrodorsata Martens and Curini-Galletti, 1989 from the Caribbean is discussed. The relationships of and within the genus Tajikacelis n. gen. are discussed and compared with recent results based on DNA studies. 


1988 ◽  
Vol 78 (3) ◽  
pp. 493-509 ◽  
Author(s):  
Garrick McDonald ◽  
Roger A. Farrow

AbstractAerial sampling for Nysius vinitor Bergroth was undertaken in the surface and upper air, at altitudes of 2 and 100-300 m, respectively, at Trangie in central New South Wales and at Corny Point, Yorke Peninsula, South Australia. Insects were sampled for 15 periods, each of 3-11 days, between October 1979 and February 1984, covering all months except January, March and May. N. vinitor was one of the most abundant insects caught in the upper air during the day and night (mean density of 652/106 m3), while the congeneric N. clevelandensis Evans was rarely caught at any time. N. vinitor was caught in all months sampled except for the winter months of July and August, and the largest daily catches occurred in September. Females were generally less common than males, although the relative incidence in the upper air catches frequently increased significantly from day to night. Fewer mature females were caught in the upper air (0-16·8%) than at the surface (0-48·4%). Densities were generally much greater in the surface air than in the upper air, although during the major flights of spring, there was less than a two-fold difference, indicating increased migratory activity. Migration occurred in a range of synoptic conditions resulting in the displacement of individuals in a variety of directions and distances depending on synoptic flow at the time of flight. Major migrations occurred at night, following dusk take-off, in disturbed weather associated with prefrontal airflows. These resulted in net southward displacements of ca 200-300 km depending on flight duration. It is suggested that major immigration flights into central-western New South Wales and regions to the south regularly occur in early spring (September-October) and probably arise from breeding areas in subtropical latitudes.


2017 ◽  
Vol 57 (2) ◽  
pp. 526
Author(s):  
Will Pulsford

The Australian Energy Market Operator (AEMO) issued a Gas Statement of Opportunities in March 2016, which reports that gas supply to the domestic and liquefied natural gas markets in eastern Australia will be largely satisfied by proved and probable reserves until 2026 and by the addition of contingent resources until 2030. However, in parallel, there are widely reported concerns by energy consumers of insufficient gas supplies to meet demand by the early 2020s and a lack of new gas supplies to replace existing expiring contracts. Gas shortages have already contributed to black outs and load shedding events in South Australia. This paper reviews the eastern Australian gas supply position at a basin level. The AEMO basin level supply forecasts are reviewed and adjusted to generate forward profiles, which are consistent with reported reserves levels, production histories and depletion behaviour of typical gas fields. The revised supply forecast is compared with the AEMO’s demand profiles, and the likely commercial behaviour of key participants in the market is considered to build a picture of the domestic gas supply-demand balance through the 2020s. This analysis provides a transparent link from market outcomes back to the underlying reserves classifications to guide interpretation of supply-demand forecasts, and highlights the critical role of key suppliers in the eastern Australian gas market in the coming decade.


1999 ◽  
Vol 50 (7) ◽  
pp. 1233 ◽  
Author(s):  
G. H. Baker ◽  
P. J. Carter ◽  
V. J. Barrett

The earthworm fauna of pastures in south-eastern Australia is dominated by exotic lumbricid earthworms, in particular the endogeic species, Aporrectodea caliginosa and A. trapezoides. Anecic species such as A. longa are very rare. All 3 species were introduced within cages in 10 pastures on a range of soil types within the region. Five months later, A. longa had generally survived the best and A. trapezoides the worst. The survivals and weights of individual worms varied between sites for all 3 species. The survivals of A. caliginosa and A. longa, and to a lesser extent A. trapezoides, were positively correlated with soil clay content. The weights of A. caliginosa and A. longa, but not A. trapezoides, were positively correlated with soil P content. The survivals and weights of A. longa and A. trapezoides and the weights only of A. caliginosa decreased with increasing inoculation density, suggesting increased intraspecific competition for resources, particularly in the first two species. A. longa reduced the abundance and biomass of the exotic acanthodrilid earthworm, Microscolex dubius, at one site, and the total biomass of 3 native megascolecid species at another, when these latter species occurred as contaminants in A. longa cages. The addition of lime had no effect on the survivals and weights of A. caliginosa, A. longa, and A. trapezoides, although the soils were acid at the sites tested. The addition of sheep dung increased the survival and weights of some species at some sites. Mechanical disturbance of the soil within cages reduced the survivals of A. longa and A. trapezoides. A. longa was released without being caged at 25 sites within one pasture in South Australia. Four years later, it was recovered at all release points. A. longa has the potential to colonise pastures widely throughout the higher rainfall regions of south-eastern Australia.


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