摘要:

There are two genera of tarphycerid and one new genus of ellesmerocerid in the upper Lower to Upper Ordovician Gordon Subgroup of Tasmania. The ellesmeroceridCentrocyrtocerina frizonensisgen. et sp. nov. was collected from the Cashions Creek Limestone in the Florentine Valley;Centrocyrtocerinasp. was collected from Ida Bay. The tarphyceridTrocholitoceras idaenseTeichert & Glenister (1953) is reassigned toDiscocerasandDiscocerassp. is reported from Bubs Hill and Smelters Quarry, Zeehan.Pycnoceras adamsensefrom the base of the Karmberg Limestone at Adamsfield is described.

ISSN:0311-5518    

DOI:10.1080/03115518308619611

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The genusTroposodoncontains at least five species, includingTroposodon bowensissp. nov. from the early Pliocene Bow local fauna of New South Wales, andTroposodon gurarsp. nov. from the Pliocene Chinchilla local fauna of Queensland. The morphology of premaxillary and post-cranial remains ofT. bowensisdescribed here resemble those of other sthenurine kangaroos. Species ofTroposodonwere widespread and diverse during the Pliocene in eastern Australia, but declined to extinction during the Pleistocene. At least two species seem to have existed sympatrically at most localities where species ofTroposodonoccur.

ISSN:0311-5518    

DOI:10.1080/03115518308619612

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The Oligocene vegetation at Pioneer was closed temperate rainforest dominated byNothofagus johnstoniiHill, which probably producedN. menziesii-type pollen. However, other angiosperms (Quintinia, Cupaniae,Ilex, Cunoniaceae, Myrtaceae, Proteaceae and Winteraceae) were also present, as well as several conifers (Athrotaxis, Phyllocladus, Podocarpus, Dacrydium, Dacrycarpusand Araucariaceae). This rainforest was floristically more complex that the modern TasmanianNothofagus cunninghamiirainforests but contained many taxonomically related elements. One major difference was that a fern similar to extantCyatheafilled the riparian niche now largely occupied by the tree-fernDicksonia antarctica. There is indirect evidence that species producingNothofagus brassii-type pollen may have occurred upstream of the site of deposition, suggesting that theNothofagusspecies were altitudinally zoned or edaphically restricted. The current absence of many of theseNothofagusspecies in Tasmania may be due to their inability to survive the low temperatures of the Quaternary glaciations. The high degree of similarity of the Pioneer palynoflora to that recorded in Oligocene sediments in onshore (Partridge, 1971) and offshore (Stover & Partridge, 1973; Stover & Evans, 1973) Gippsland Basin strongly suggests that there was little regional differentation in southeastern Australia at that time.

ISSN:0311-5518    

DOI:10.1080/03115518308619613

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Regional biofacies analysis has been neglected in biostratigraphic studies of the Cambrian-Ordovician boundary interval. Cluster analysis of relative abundance data of trilobites in thirty-seven large collections from ten localities in North America outlines eleven biofacies in the mid-Trempealeauan to early Tremadocian interval. The biofacies are largely lithofacies-specific and are differentiated at generic and familial levels. The composition of trilobite zonal associations in the boundary interval is controlled principally by the sequence of biofacies. Available trilobite zonal schemes can be used only within single lithofacies. The biofacies patterns and faunal dynamics across the upper boundary of the Ptychaspid Biomere do not support hypotheses requiring catastrophic events. In coherence and geographic distribution, Late Cambrian trilobite biofacies are similar to post-Cambrian benthic biofacies.

ISSN:0311-5518    

DOI:10.1080/03115518308619614

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

A new genus and species of carpoid (‘homalozoan’) echinoderm (class Stylophora, suborder Mitrata, order Anomalocystitida),Tasmanicytidium burretti, is described from the Early Silurian of Tasmania, Australia. It is attributed to the Allanicytidiidae, formerly known only fromAllanicytidium flemingiCaster & Gill (1967) (Early Devonian, New Zealand).Notocarpos garrattiPhilip (1981) (Late Silurian, Victoria) is also assignable to this family. With these new attributions, considerable revision of the Allanicytidiidae is required. The class Carpoidea Jaekel (1901, 1921) is reinstated at the subphylum level and corresponding elevation in rank of inferior hierarchic categories is made. Several new morphologic terms and interpretations are proposed. Without serial rubber casting, erroneous interpretations of the natural moulds would have resulted.

ISSN:0311-5518    

DOI:10.1080/03115518308619615

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor