摘要:

Fossil remains of primitive vertebrates, preserved in sandstone as natural moulds of the dermal armour, are described from the shallow-water marine Stairway Sandstone of the Amadeus Basin, Northern Territory, Australia. This is the first record of Ordovician vertebrates in the southern hemisphere. Two new genera and species,Arandaspis prionotolepisgen. et sp. nov. andPorophoraspis crenulatagen. et sp. nov., are described.Arandaspisis the most completely preserved of any known Ordovician vertebrate. It is the type genus of the new family Arandaspididae, and is referred to the new order Arandaspidiformes. The new Australian genera are provisionally interpreted as heterostracans, a group of agnathans not previously recorded from Australia.

ISSN:0311-5518    

DOI:10.1080/03115517708527770

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

A locality in the Late Devonian Cloghnan Shale (Nangar Subgroup) near Forbes, N.S.W., has yielded a rich vertebrate fauna including the antiarchsBothriolepisandRemigolepis, the phyllolepidPhyllolepis, the dipnoanSoederberghia, and the jaw of a new ichthyostegaliid amphibianMetaxygnathus denticulusgen. et sp. nov. The amphibian is the oldest known member of the group with the possible exception ofElpistostegeWestoll, and it retains characters previously associated with the rhipidistian fishes. The musculatures of rhipidistian and amphibian jaws are analysed and are shown to be functionally related to distinctive morphologies of the articulatory region in each group,Metaxygnathusbeing of amphibian type. Comparison is made with the Greenland ichthyostegids, and rhipidistians such asEusthenodon.

ISSN:0311-5518    

DOI:10.1080/03115517708527771

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The presence of two types of xiphodont crocodiles is reported for the first time from Australia. Crocodiles with this xiphoid type of tooth morphology were previously unknown anywhere in the world since the Miocene except for isolated xiphoid teeth noted by Plane (1967) from a Pliocene deposit in New Guinea.

ISSN:0311-5518    

DOI:10.1080/03115517708527772

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

ISSN:0311-5518    

DOI:10.1080/03115517708527773

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Silicified layers of plant material from the Late Permian Blackwater Group of the Bowen Basin, Queensland, contain seed-bearing organs associated withGlossopterisleaves; comparison of these organs with attached fertile glossopterid structures previously described from compressions indicates the petrified organs are undoubtedly ofGlossopteris. The fructification consists of an infolded megasporophyll with loosely overlapping lateral margins forming an envelope bearing sessile gymnospermous seeds on the inner surface. The seeds contain a megagametophyte with one archegonium. Previous interpretations of fertile glossopterid structures as cupular valves, fertiligers, and cones with a subtending bract, e.g.DictyopteridiumandScutum, are now reinterpreted as having a similar arrangement of megasporophyll envelope (= subtending bract of ‘cone’) enclosing the seeds.

ISSN:0311-5518    

DOI:10.1080/03115517708527774

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Well preserved lingulids from near the base of the Mandagery Sandstone in the Late Devonian Hervey Group, N.S.W. are described asApsilingula parkesensisgen. et sp. nov. The internal structures are better preserved than those of any previously described Palaeozoic lingulid and it has been possible to reconstruct the muscle system and to demonstrate a close similarity to living species ofLingula.

ISSN:0311-5518    

DOI:10.1080/03115517708527775

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor