Crinoids from the Middle Jurassic (Bajocian–Lower Callovian) of Ardèche, France

2012 ◽  
Vol 131 (2) ◽  
pp. 211-253 ◽  
Author(s):  
Hans Hess
1959 ◽  
Vol 96 (6) ◽  
pp. 505-512 ◽  
Author(s):  
J. H. Callomon

AbstractNew discoveries have established the presence of nine ammonite zones in the Middle Jurassic beds of East Greenland. The top two are Lower Callovian; the remaining seven yield ammonites unknown from extra-Boreal provinces and are presumed to range down through the Bathonian, possibly into the Bajocian.


2002 ◽  
Vol 21 (2) ◽  
pp. 155-166 ◽  
Author(s):  
Martin Ware ◽  
Robin C. Whatley

Abstract. The Upper Bathonian and Lower Callovian ostracod species Fastigatocythere juglandica (Jones, 1884) is shown to comprise a total of five subspecies. Of these, F. juglandica juglandica, F. juglandica major (Jones & Sherborn, 1888) and F. juglandica postrotunda subsp. nov., described as new herein, are all confined to the Upper Bathonian. Lophocythere fulgurata (Jones & Sherborn, 1888) is demonstrated to be an instar of F. juglandica major. Fastigatocythere juglandica degenerata subsp. nov., described as new herein and F. juglandica rugosa Weinholz comb. nov., both confined to the Lower Callovian, extend the known range of the species into that stage for the first time.


1987 ◽  
Vol 24 (8) ◽  
pp. 1570-1582 ◽  
Author(s):  
Jai Krishna ◽  
G. E. G. Westermann

New collections of Macrocephalitinae from the ?Upper Bathonian – Lower Callovian of Kachchh (Cutch olim) make it possible to discern six successive taxonomically distinguishable faunal associations. These are, from above, (6) M. semilaevis association, (5) M. formosus association, (4) M. dimerus association, (3) M. elephantinus association, (2) M. madagascariensis association, (1) M. triangularis association.Of these, Nos. 1, 4, and 6 formed the bases of the M. triangularis, M. dimerus, and M. semilaevis biozones respectively. The majority of the 19 nominal species and 6 genera in the literature on Kachchh may be condensed into only 6 dimorphic species of undivided Macrocephalites.


2004 ◽  
Vol 5 ◽  
pp. 31-49 ◽  
Author(s):  
Peter Alsen ◽  
Finn Surlyk

A Middle – lower Upper Jurassic sandstone-dominated succession, more than 550 m thick, with mudstone intercalations in the middle part is exposed in Bjørnedal on Traill Ø, North-East Greenland. A number of ammonite assemblages have been found, mainly in the mudstones. They indicate the presence of the Lower Callovian Cadoceras apertum and C. nordenskjoeldi Chronozones. The mudstones represent northern wedges of the Fossilbjerget Formation hitherto known only from Jameson Land to the south. In Bjørnedal they interfinger with sandstones of the Pelion and Olympen Formations. The presence of the Fossilbjerget Formation in this region indicates complete drowning of the Middle Jurassic sandstone-dominated Pelion Formation during maximum Middle Jurassic transgression. A new species, Kepplerites tenuifasciculatus, is described in the appendix by J.H. Callomon. The holotype and paratype are from Jameson Land, East Greenland, but the species is also found in Bjørnedal, Traill Ø, North-East Greenland.


1993 ◽  
Vol 40 ◽  
pp. 83-113
Author(s):  
John H. Callomon

The ammonite sequence in the Middle Jurassic of central East Greenland is the most complete and detailed known in the Arctic so far, and has become a standard of reference for the whole of the Bo real Faunal Province. It is made up of some 37 distinguishable assemblages that characterize a time-ordered succession of discrete faunal horizons. This succession has been pieced together from over 80 recorded sections in Jameson Land lying between Scoresby Sund and Kong Oscars Fjord (70-72°N). It forms the biostratigraphic basis for the regional chronostratigraphy. The faunal assemblages are listed and described by reference to published illustrations in the literature. Faunas 1-23 are of pre-Callovian age and have no elements in common with their contemporaries in the classical regions of Europe. They still cannot be correlated with the European standard pre-Callovian chronozonations. Most of them must be of Bathonian age, although the earliest of them could well be, and probably are, even still Upper Bajocian. The Bathonian-Callovian boundary most probably lies some­where in faunas 24-26, which closely resemble those of the keppleri horizon at the base of the Callovian. Faunas 27-35 span the rest of th􀁋 Lower Callovian, while faunas 36 and 37 are the only evidence of Middle and Upper Callovian. The ammonites from Jameson Land previously described by Spath (I 932) are revised and assigned to their correct horizons. Of 11 new species, only one is formally named: Kepp/erites vardekloeftensis sp. nov., of latest Bathonian age.


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