Chromosome, morphometric and breeding system studies in the Stylidium caricifolium species complex (Stylidiaceae)

1981 ◽  
Vol 29 (4) ◽  
pp. 397 ◽  
Author(s):  
DJ Coates
Keyword(s):  
Transition Zone ◽  
Western Australia ◽  
Breeding System ◽  
Species Complex ◽  
Leaf Morphology ◽  
Evolutionary Relationships ◽  
Geographic Patterns ◽  
Floral Characters ◽  
Ecological Transition

Evolutionary relationships among the five species in the Stylidium caricifolium species complex were investigated by chromosome, morphometric and breeding system studies. Marked interspecific chromosome differences were found between all five species and chromosomally polymorphic individuals detected in populations of S. affine, S. caricifolium and S, sp. 2. In addition, chromosomal and morphological intermediates between S. affine and S. caricifolium were found in a region corresponding to an ecological transition zone between the wheat belt and Darling Scarp vegetation systems in southern Western Australia. The origin of these transition-zone forms, although conjectural at this stage, is discussed in the light of information available from chromosome studies. Morphometric studies demonstrated that S. affine, S. sp. 1 and S. sp. 2 can readily be distinguished from each other and from S. nungarinense and S. caricifolium. The last two species, although not detectably different in the floral characters measured, can be separated on leaf morphology. Breeding system studies suggested that all species with the exception of S. affine and S. caricifolium are effectively isolated from each other reproductively. The possible significance of chromosome repatterning and eco-geographic patterns in the evolution of the S. caricifolium species complex is discussed.

Paleozoic dipnoan phylogeny: functional complexes and evolution without parsimony

Paleobiology ◽  
1990 ◽  
Vol 16 (2) ◽  
pp. 143-169 ◽  
Author(s):  
K. S. W. Campbell ◽  
R. E. Barwick
Keyword(s):  
Western Australia ◽  
Upper Devonian ◽  
Morphological Data ◽  
Evolutionary Relationships ◽  
New Genera ◽  
Evolutionary Patterns ◽  
Dermal Bones

Attempts at understanding evolutionary relationships among Paleozoic Dipnoi (lungfish) using cladistic methodology have proved totally unsatisfactory (Miles 1977; Marshall 1987). We attempt to reconstruct the relationships between the better known genera using a method that involves the recognition of lineages based on evolving functional complexes, particularly those involved with food reduction and respiration. Within these broadly defined lineages, we have defined sub-lineages based on evolutionary patterns shown by structures that have been stratigraphically dated; such patterns are found inter alia in the roofing bones and the external dermal bones of the mandible. A number of new suborders and families are recognised; genera for which further morphological data are required before they can be assigned to a higher taxon are indicated; two generic synonyms are recognised.In appendices, short descriptions are given of two new genera—Pillararhynchus from the Gogo Formation (Upper Devonian) of Western Australia, and Sorbitorhynchus from the Emsian of Guangxi, China.

A new species of Parasesarma (Crustacea: Brachyura: Sesarmidae) from the mangroves of Western Australia

Zootaxa ◽  
2010 ◽  
Vol 2564 (1) ◽  
pp. 62 ◽  
Author(s):  
P. J. F. DAVIE ◽  
L. PABRIKS
Keyword(s):  
New Species ◽  
Western Australia ◽  
Adult Male ◽  
Species Complex ◽  
Shark Bay ◽  
A New Species

A new species of intertidal sesarmid crab, Parasesarma hartogi, is described from the upper mangrove zone in Shark Bay, Western Australia. It differs from its four closest relatives in the P. plictatum species-complex by being broader between the epibranchial angles than between the exorbital angles; showing differences in the number and form of the dorsal dactylar tubercles of the male cheliped, a relatively broader gape between the fingers of the adult male chelae, proportions and shape of the male abdomen, and shape of the male first gonopod.

New species of xeromorphic Banksia (Proteaceae) foliage and Banksia-like pollen from the late Eocene of Western Australia

2020 ◽  
Vol 68 (3) ◽  
pp. 165 ◽  
Author(s):  
Raymond J. Carpenter ◽  
Lynne A. Milne
Keyword(s):  
New Species ◽  
Western Australia ◽  
Leaf Morphology ◽  
Lower Surface ◽  
Late Eocene ◽  
Leaf Type ◽  
Late Neogene ◽  
Evolutionary Pathways ◽  
Climatic Aridity ◽  
Western Australian

Banksia microphylla leaf fossils and Banksieaeidites zanthus pollen are newly described from late Eocene lignite of the Zanthus-11 borehole, drilled east of Norseman in Western Australia. The leaf fossils are the first known in Banksia to show extreme narrowness (<1.5 mm wide) combined with the xeromorphic trait of margins rolled onto the lower surface so that the diffusely placed stomata are exposed to the outside environment only via grooves on each side of a thick, abaxial midrib. Both this Banksia leaf type and another with encrypted stomata evolved before the widespread initiation of severe climatic aridity in the late Neogene, likely in regions of edaphic infertility and periodic water stress. New interpretations of leaf morphology and foliar evolutionary pathways in Banksia are proposed. Banksia microphylla probably belongs to subgenus Spathulatae, where it strongly resembles many species in the large, wholly Western Australian clade that includes most species in section Oncostylis, series Abietinae. Banksieaeidites zanthus is morphologically consistent with Banksia pollen, and its extremely small size also suggests placement in Spathulatae. The new fossils and other evidence from Zanthus-11 indicate the local presence of quite open, sclerophyll vegetation with conifers, which was unlikely to have been frequently burnt.

Groundwater oligochaetes show complex genetic patterns of distribution in the Pilbara region of Western Australia

2015 ◽  
Vol 29 (5) ◽  
pp. 405 ◽  
Author(s):  
Louise Brown ◽  
Terrie Finston ◽  
Garth Humphreys ◽  
Stefan Eberhard ◽  
Adrian Pinder
Keyword(s):  
Genetic Diversity ◽  
Western Australia ◽  
Surface Waters ◽  
Ecological Niches ◽  
Mitochondrial Coi ◽  
Groundwater Fauna ◽  
Ecological Requirements ◽  
Large Size ◽  
Geographic Patterns ◽  
Genetic Patterns

Patterns of genetic diversity in the groundwater fauna of Australia have largely focused on obligate stygobites of relatively large size, namely, crustaceans. Oligochaete worms, with their smaller size and broader ecological niches, provide a contrasting model in which to examine such patterns. Genetic diversity in subterranean oligochaetes in the Pilbara region of Western Australia were examined using one nuclear (18S) and two mitochondrial (COI, 12S) regions. The observed variation was assessed at three levels of hydrology – river basin, creek catchment, and individual bore or site – to document geographic patterns. Most species appeared to be restricted to an individual catchment; however, five species, representing three families, were widespread, with some haplotypes being shared between bores, catchments and even basins. General patterns suggest that while hydrology plays a role in the distribution of oligochaete species, it does not always confine them to catchments, in contrast to patterns observed in groundwater isopods and amphipods in the region. We suggest that intrinsic characteristics of oligochaetes, such as body size, shape, reproductive strategy and ecological requirements, may have allowed them greater dispersal within the subterranean biome of the Pilbara. In particular, oligochaetes may occupy subterranean and surface waters, increasing their opportunities for dispersal.

Genetic entities and hybridisation within the Acacia microbotrya species complex in Western Australia

2015 ◽  
Vol 11 (4) ◽  
Author(s):  
R. M. Binks ◽  
M. O’Brien ◽  
B. MacDonald ◽  
B. Maslin ◽  
M. Byrne
Keyword(s):  
Western Australia ◽  
Species Complex

Patterns of Distribution of Acacia in Australia

1988 ◽  
Vol 36 (4) ◽  
pp. 385 ◽  
Author(s):  
BR Maslin ◽  
L Pedley
Keyword(s):  
Species Richness ◽  
Western Australia ◽  
Arid Zone ◽  
Patterns Of Distribution ◽  
The North ◽  
Geographic Patterns ◽  
South West ◽  
Eastern Australia ◽  
Semiarid Areas ◽  
The Tropics

Patterns of distribution are described for the three subgenera and nine sections that make up the Australian Acacia flora. Subgenus Phyllodineae (833 species) is widespread and contains 99% of the species; subgenus Acacia (six species) and subgenus Aculeiferum (one species) are poorly represented and virtually confined to the north of the continent. The geographic patterns of species-richness are strongly influenced by sections Phyllodineae (352 species), Juliflorae (219 species) and Plurinerves (178 species). Section Phyllodineae has centres of richness south of the Tropic of Capricorn in temperate and adjacent semiarid areas of eastern, south-eastern and south-western Australia. The section is poorly represented in the tropics. The closely related sections Juliflorae and Plurinerves predominate in the north of the continent, semiarid areas of the south-west, many rocky tablelands of the Arid Zone and along the Great Dividing Range and adjacent inland riverine lowland areas in eastern Australia. The remaining four sections contribute little to the overall patterns of species-richness. The principal speciespoor areas are sandy and fluvial lowland regions of the Arid Zone. In eastern Australia, sections Botrycephalae, Juliflorae, Phyllodineae and Plurinerves show discontinuous patterns of species-richness along the Great Dividing Range. All sections have species whose ranges terminate in the area of the McPherson-Macleay Overlap region.

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