Permian Ammonoids Research Articles

ENDEMIC PERMIAN AMMONOID GENUS YINOCERAS, CENTRAL HUNAN, SOUTH CHINA

Abstract Revision and redefinition of the Permian ammonoid genus Yinoceras Chao, 1954, is based upon examination of the holotype of its type species, Y. lenticulare Chao, plus new material collected from the Kungurian Dangchong Formation of central Hunan, China. Yinoceras is a valid yinoceratin genus within the pseudohaloritid Superfamily Pseudohaloritoidea, Suborder Tornoceratina, Order Goniatitida.

Carboniferous and Permian Ammonoids from Northern Thailand : Paleontological Study of Paleozoic Cephalopods in Southeast Asia-1

Carboniferous and Permian Ammonoids from Northern Thailand : Paleontological Study of Paleozoic Cephalopods in Southeast Asia-1

Mass extinctions and sea-level changes

Review of sea-level changes during the big five mass extinctions and several lesser extinction events reveals that the majority coincide with large eustatic inflexions. The degree of certainty with which these eustatic oscillations are known varies considerably. Thus, the late Ordovician and end Cretaceous extinctions are associated with unequivocal, major regressions demonstrated from numerous, widespread regions. In contrast, the multiple, high frequency sea-level changes reported for the Frasnian–Famennian crisis (based on the supposed depth-preferences of conodont taxa) have little support from sequence stratigraphic analyses, which reveals the interval to be one of highstand. The end Permian mass extinction has long been related to a severe, first order lowstand of sea level [Newell, N.D., 1967. Revolutions in the history of life. Geol. Soc. Am. Spec. Pap. 89, 63–91.] based primarily on the widespread absence of latest Permian ammonoid markers, but field evidence reveals that the interval coincides with a major transgression. Newell's hypothesis that marine extinctions are related to shelf habitat loss during severe regression remains tenable for the end Guadalupian and end Triassic extinction events but not for other crises. Rapid high amplitude regressive–transgressive couplets are the most frequently observed eustatic changes at times of mass extinction, with the majority of extinctions occurring during the transgressive pulse when anoxic bottom waters often became extensive. The ultimate cause of the sea-level changes is generally unclear. A glacioeustatic driving mechanism can only be convincingly demonstrated for the end Ordovician and end Devonian events. At other times, it is speculated that they may relate to the widespread regional doming (and subsequent collapse) caused by the impingement of superplumes (and ultimate eruption) on the base of the lithosphere.

Discovery of an Early Permian (Late Sakmarian) ammonoid from Langkawi Island, Malaysia

This paper describes a single specimen of Metalegoceras sp. recently discovered from the upper part of the Singa Formation at Batu Asah on the main Langkawi Island off the northwestern coast of Peninsular Malaysia. The discovery represents the first report of a Permian ammonoid from the island and from the Singa Formation and confirms a Sakmarian (Early Permian) age for this part of the formation suggested by brachiopods.

Permian Ammonoids from the Loei area, Northeast Thailand

Permian Ammonoids from the Loei area, Northeast Thailand

Upper Permian (Wordian) fusulinaceans from the Cache Creek Terrane, northern British Columbia

Fusulinaceans from the Horsefeed Formation, the youngest stratigraphic unit within the allochthonous Cache Creek Terrane southeast of Atlin, include abundant Colania columbiana (Dawson) and Schwagerina? atlinensis Ross, as well as rare representatives of Rauserella sp. and Reichelina? sp. They occur with 13 Upper Permian (Wordian) ammonoid species, including several species of Waagenoceras that are also known from Wordian strata in Mexico and Texas. Colania columbiana was first recorded from strata at Marble Canyon within the Cache Creek Terrane in southern British Columbia by G.M. Dawson in 1879. It was identified then as Loftusia, a non-fusulinacean agglutinated foraminifer, but in the last 60 years it has been assigned to a number of Permian fusulinacean genera, including Neoschwagerina Yabe, Yabeina Deprat, and Lepidolina Lee. Colania is quite distinct from all these genera in characteristics of the shell wall. All but one species of Colania around the world are confined to strata of Wordian or equivalent age; in China, Colania douvillei (Ozawa) extends upwards into strata slightly younger than Wordian, that is, early Capitanian age. A Wordian age appears certain for Colania columbiana from British Columbia, on the basis of evolutionary development and associated ammonoids.

Permian ammonoids from Kuala Betis area, Kelantan and their paleogeographic significance

Two new Permian ammonoid bearing localities were recently discovered from Kuala Betis area, Kelantan. At Sungai Peralong, ammonoid cephalopods and some brachiopods were found in thin to moderately bedded tuffaceous siltstone and mudstone. The ammonoid fauna consists of Agathiceras cf. suessi Gemmellaro, Adrianites cf. elegans Gemmellaro, Popanoceras sp., Propinacoceras sp., ?Imitoceras sp. and some small orthoconic ammonoids. At another locality near Sungai Berok, ammonoid fauna was preserved in thin tuffaceous shale interbedded with chert and cherty mudstone. This locality yields Agathiceras cf. suessi Gemmellaro, Adrianites cf. elegans Gemmellaro, Popanoceras sp., Propinacoceras sp. and Hoffmannia cf. hoffmanni (Gemmellaro). The cephalopod assemblages from these localities partly resembles that of the middle Permian Sungai Cheroh cephalopod fauna (Lee, 1978). The Sungai Peralong, Sungai Berok and Sungai Cheroh fauna are all associated with deep water sediment within the Bentung Suture zone. Similarities between these fauna and the Italian Socio fauna and the Basleo fauna of Timor (Lee, 1978) and many other ammonoid occurrences in Europe, North Africa and West Asia (Blendinger et al., 1992) indicated that an oceanic link has been established between these pelagic fauna, perhaps as early as Lower Permian or even earlier.

The Carboniferous-Permian boundary and ammonoids from the Aidaralash section, southern Urals

The stratigraphic section at Aidaralash Creek, northern Kazakhstan, provides a complete and well-developed succession of strata across the Carboniferous–Permian boundary. This section, containing abundant and well-preserved ammonoid, fusulinacean, and conodont faunas, can serve well as the Carboniferous–Permian boundary stratotype. A profound change in ammonoid faunas, which occurs at the Orenburgian–Asselian boundary and which has been recognized by previous workers (e.g., Ruzhencev, 1950, 1951, 1952; Bogoslovskaya and Popov, 1986a, 1986b; Furnish, 1973; Glenister and Furnish, 1981), occurs in the Aidaralash Creek section, at the boundary between beds 19 and 20, and serves to mark the Carboniferous–Permian boundary. Additionally, Lower Permian strata at Aidaralash Creek mark the first appearance of widespread Permian ammonoid taxa, including representatives of Svetlanoceras, Juresanites, Prostacheoceras, Tabantalites, and Kargalites, that are preceded by the extinction of characteristic Late Carboniferous genera such as Prouddenites, Uddenites, Shumardites, Vidrioceras, Schistoceras, and Subkargalites.

Permian ammonoids from the Greville Formation, Upukerora valley, Southland

Abstract Ammonoids collected from calcareous concretions within laminated siltstones of the Greville Formation near the head of the Upukerora valley, northwestern Southland, are identified as Durvilleoceras woodmani Waterhouse. These fossils are the first occurrence of this taxon south of the Alpine Fault and the first identifiable molluscan fossils to be collected from Greville Formation in Southland. They are important because of the absence of any other identifiable fossil material from Greville rocks and also because they strengthen the existing lithostratigraphic correlation of this unit across the Alpine Fault. To date, Durvilleoceras has not been recorded from rocks other than Greville Formation. Although the age range of Durvilleoceras is unknown, and age of the Greville remains poorly constrained, this study confirms the overall stratigraphic integrity of the Maitai Group. The available data suggest that Durvilleoceras and the Greville Formation are of Late Permian age.

Ammonoid cephalopods from the Lower Permian of Thailand

The purpose of the present statement is to announce discovery of a well-preserved and potentially diverse Lower Permian ammonoid fauna from south-central Thailand. Previous Thai records of Permian ammonoids lack descriptive detail (e.g., Yanagida, 1988), but two sparse Permian occurrences from nearby areas in Malaysia have been described recently by Lee (1980). Closest similarities of the Thai material are with faunas from the Pamir (Leonova and Dmitriev, 1989) and with our undescribed collections from south Xinjiang.

Additional Early Permian ammonoid cephalopods from Western Australia

An ancestral paragastrioceratid, Svetlanoceras irwinense (Teichert and Glenister, 1952), and a specifically indeterminate gonioloboceratid, cf. Mescalites sp., from the basal Callytharra Formation are described as the oldest ammonoids recovered from the Permian of the Carnarvon Basin, Western Australia. Identity of these taxa strengthens correlation with the Holmwood Shale (Sakmarian) of the adjacent Perth Basin. Svetlanoceras moylei Mikesh, n. sp., from the Lenox Hills Formation of West Texas, is described for comparison with other simple paragastrioceratids.

Late Permian ammonoid cephalopod Cyclolobus from Western Australia

A single specimen of Cyclolobus persulcatus Rothpletz (1892), a species interpreted as a primitive member of the genus, is described from the Cherrabun Member of the Hardman Formation, Liveringa Group, Canning Basin, Western Australia. It is the youngest Permian ammonoid known from Australia. Type and other representatives of C. persulcatus from Indonesia (Timor) are part of the “Amarassi fauna,” which is considered post-Guadalupian. Cyclolobus is sporadically abundant and widely distributed in the Dzhulfian Stage, and probably extends into the overlying Dorashamian Stage.

Uppermost Permian ammonoids from northern Thailand

Uppermost Permian (Dorashamian) ammonoids, Pseudogastrioceras aff. P. guangxiensis Zhao et al., Paratirolites nakornsrii sp. nov. and Xenodiscus? sp. occur in the Huai Thak Formation near Lampang, northern Thailand. The stratigraphical sequence of the Huai Thak and Phra That Formations appears to extend from the Permian into the Triassic without a break from field observations. The present faunule is found at a distinct stratigraphical horizon about 50 m below the occurrence of Triassic bivalve Claraia (Lower Scythian). An Uppermost Permian Palaeofusulina fauna-bearing limestone bed is also present in the same area of Doi Pha Phlung and represents a related heteropic facies of the ammonoid-shale bed. Paleontological evidence is thus available to establish the position of the boundary between the Permian and the Triassic in this province.

南部北上山地のペルム紀アンモナイト類 その層位的分布とペルム系の分帯

南部北上山地のペルム紀アンモナイト類 その層位的分布とペルム系の分帯

Two ecological patterns of the Permian ammonoids

This paper attempts to divide the Permian ammonoids and the paleogeographical environments into two ecological patterns, the restricted sea pattern and the open-sea pattern. The former represents a new shallow-water pattern which evolved within the epicontinental sea with some barriers. It has been emphasized that the differances in facies should be considered in making regional correlation of the ammonoid-bearing strata.

Pennsylvanian-Permian Cheiloceratacean Ammonoid Families Maximitidae and Pseudohaloritidae

Cheilocerataceae are unique among Pennsylvanian and Permian ammonoids in having maintained the primitive sutural condition in which the ventral lobe remained entire or, in rare cases, incipiently bifid. The mature ventral lobe of all contemporary ammonoids is either prominently bifid or weakly trifid. Identity of these younger cheilocerataceans is confirmed by an additional distinctive feature, the phyletic migration of the siphuncle from a ventral position to lie close to the dorsum within the dorsal septal flexure.Transformation of the ancestors, the Mississippian cheiloceratacean family Prionoceratidae, to produce the root-stock of post-Mississippian Cheilocerataceae was by progenesis (paedomorphosis and neoteny). This involved linear size reduction by a factor of ten, and retention to maturity of the rounded (formerly juvenile) character of the lateral lobe.Two families are represented in the Pennsylvanian, both probably derived from a common prionoceratid ancestor. The monotypic Maximitidae (Atokan-Missourian) are distinguished by ontogenetic migration of the siphuncle from a central to ventral-marginal position, with concurrent development of incipient bifurcation of the ventral lobe in some forms. The more diverse and longer ranging Pseudohaloritidae are represented in the Pennsylvanian (Missourian and younger) by Neoaganides, an unornamented form with simple sutures that persisted to the extinction of the superfamily in the highest Permian Changhsingian Stage. During the Permian, the Pseudohaloritidae underwent explosive diversification, displayed especially by the Wordian endemics of South China. This involved bizarre combinations of shell features that are duplicated by some Mesozoic ammonoids but are rare or unique for the Paleozoic. Included are coarse ribs and nodes, and mature modifications comprising divergent coiling, one or two subterminal constrictions, and one or two pairs of spectacular lappets. In addition both the lobes and saddles may be irregularly but extremely denticulate to give “ceratitic” and “ammonitic” sutures, and the siphuncle is generally close to the dorsum. No fully plausible explanation has yet been provided for these late evolutionary developments.All previously described taxa in the Maximitidae and Pseudohaloritidae are reviewed. New taxa include a species of Maximites that is dimorphic, three new forms of Neoaganides from the Permian of Texas and Iran, plus the first representatives of Pseudohalorites and Shouchangoceras from North America. A new genus (Sosioceras) is established for Brancoceras pygmaeum Gemmellaro. It differs from Neoaganides in having a doubly constricted aperture at maturity and well developed runzelschicht. This monotypic genus is dimorphic also, and strong dimorphism may be characteristic of Permian Pseudohaloritidae.Sutures provide the basis for subdivision of the Pseudohaloritidae into subfamilies. The Shouchangoceratinae are “goniatitic,” the Pseudohaloritinae are “ceratitic,” and the Lanceoloboceratinae are “ammonitic.” The inadequately known Yinoceratinae, referred previously to the Thalassoceratidae, are shown to be closely related to their geographic and stratigraphic associates, the Lanceoloboceratinae. It is doubtful whether separation of the two subfamilies can be maintained. Although features such as sculpture and degree of development of serration of the suture are highly variable at the species level, gross changes in these features and in the form of the mature aperture are nonetheless the best taxobases for genera and species since the number of lobes remained constant at eight.

Reinterpretation of ceratitic ammonoids from the Greville Formation, New Zealand

SummaryCeratitic ammonoids from the Greville Formation in the Nelson Regional Syncline, South Island of New Zealand, were described as a new genus and species of the Ophiceratidae, Durvilleoceras woodmani, and dated as ‘late Middle Permian’ (Waterhouse, 1973). In fact, Durvilleoceras differs from all known Permian ammonoids in both conch form and sutural pattern, but closely resembles lower Triassic ceratites. Structural and sedimentologic complexities within the Nelson Syncline are such that stratigraphic interpretations are questionable, and the fauna of both the Greville and adjacent formations is sparse. Consequently, we consider that Durvilleoceras is best interpreted as a middle Scythian ceratite of the family Flemingitidae.

Permian Ammonoid Cyclolobus from the Zewan Formation, Guryul Ravine, Kashmir

Ammonoid cephalopods serve significantly as a basis for correlation of strata near the boundary between the Paleozoic and Mesozoic Erathems. This is a report of the diagnostically Late Permian (uppermost Paleozoic) ammonoid Cyclolobus walkeri (Diener, 1903) from the Zewan Formation 20 meters below the Permian-Triassic contact at the classic section in Guryul Ravine, Srinagar region, Kashmir.

The evolution, correlation, and paleogeographic significance of the Permian ammonoid family Cyclolobidae

The Permian ammonoid family Cyclolobidae Zittel is essentially of Middle Permian age, and most species ranged over the paleotropical into temperate regions, and lived for no more than one to three stages. The time ranges of the three principal genera, Waagenoceras, Timorites and Cyclolobus overlap to some degree, so correlation must be based on species rather than genera. Cyclolobus evolved from Godthaabites, and both inhabited temperate paleolatitudes on the whole. Cyclolobus inhabited a small region, now dispersed around the rim of the Indian Ocean. The Waagenoceras - Timorites lineage, contemporaneous with the Godthaabites-Cyclolobus suite, inhabited paleotropical latitudes, and Timorites is found around the rim of the Pacific Ocean. Such genera, restricted in longitudinal as well as latitudinal distribution, are important in constructing pre-drift distribution of plates. The Kalabarghian and Chhidruan faunas of the Salt Range are identical with the Capitan Stage (sensu lato) of Texas. Younger Permian rocks and faunas are subdivided into the Kathwai fauna, the Baisalian, Vedian, Ogbinan faunas, followed by the Makarewan Stage of New Zenland.

Permian ammonoids from Eastern Australia

Abstract Two new species of Uraloceras, U. lobulatum, and U. whitehousei from the lower part of the Tiverton Formation at Homevale, northwest of Nebo, Queensland, have affinities with Artinskian and probably early Artinskian (Aktastinian) species from the type areas of the Lower Permian in the Ural Mountains, Russia. A possibly similar species, Uraloceras pokolbinense (Teichert), occurs in the Farley Formation in the Hunter Valley of New South Wales. The rich invertebrate fauna associated with the ammonoids at Homevale belongs to Fauna II of Dickins and it is now known that species of Neocrimites are associated with a similar fauna at Chatsworth, north of Gympie, and probably with the same fauna in the Lakes Creek Beds near Rockhampton. Neocrimites meridionalis Teichert & Fletcher from the lower part of the Branxton Sub‐group in the Hunter Valley may also be of a similar age. Since Neocrimites has not been recorded from beneath the upper (Baigendzhinian) substage of the Artinskian, some of the rocks conta...