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Chapter 58. Palaeogeography of Tethyan Cretaceous marine ostracods.

Chapter 58. Palaeogeography of Tethyan Cretaceous marine ostracods.

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824 J.-F. BABINOT

AND J.-P. COLIN



affinity trends existing between the different geographical areas and to characterize bioprovinces.

These problems are essentially treated at the genus level although a few examples at the species

level will be evoked. The main paleobiogeographic implications will be used to better understand

the dynamics of the associations during time, and in general, to contribute to improving our

knowledge of the structural evolution and relationships of the Tethyan margins.

First of all, it is important to define precisely the word “Tethys.” According to Suess (1893),

the Tethys concept corresponds to a wide latitudinal Mesozoic ocean situated between Africa and

Eurasia. This concept was modified later by Wegener, Tethys becoming the ocean separating the two

main blocks of his structural reconstructions: Laurasia and Gondwana land. The geographical and

physical characteristics of this ocean have subsequently been intensively discussed. Was this ocean

wide or narrow? Was it thermo-or psychrospheric? How deep was it? In fact, a more precise definition of the Tethys can be given through different methodologies. This has been judiciously

noted by McKenzie (1982, p. 313), “. . . modern biogeographers studying Tethys are encouraged

to evaluate two differing options of its nature - one, the by now conventional Wegenerian model

updated to conform with paleomagnetism and sea-floor spreading, the other based more on faunal

distribution and general geology .” However, concerning the Cretaceous, there is general agreement

on the existence of a rather narrow seaway between the African and Eurasian blocks, connecting

two much wider marine areas: one in the West, equivalent to the Proto-Atlantic Ocean (Gulf of

Mexico, Caribbean and Northern part of South America), the other in the East, paleogeographically located between East Africa-India-Australia and Eastern Asia (Barron et al., 1981).

In 1900, Douvilli: created the word “Mesogea” for a latitudinal sea corresponding to the palaeogeographical extension of rudists during the Cretaceous. This sea more or less coincides with the

Tethyan realm. In both cases, the definition of the oceanic area is related to the distribution of

mollusk faunas. Paleoclimates played a fundamental role. A more recent definition for the Mesogea has been proposed (Philip, 1982), characterized by the development of rudist limestone formations. This definition, although in perfect agreement with DouvillC’s thinking, is restricted to a

peculiar sedimentologic domaine of carbonate platforms. Ostracod biotopes being much more

diversified, the Tethyan concept is more appropriate because it involves not only paleoclimatic and

sedimentologic criteria, but other parameters.

Our bibliographical knowledge on Cretaceous ostracods of this extensive area is not negligible.

It is, however, worth noting the disparity of the available information, e.g. scarcity of data concerning the Valanginian-Aptian interval versus sound knowledge of the Senonian, and especially of

the Cenomanian.

In recent years, few palaeogeographical attempts extending from strictly regional frameworks

have been made. This is the case for the relations between North American and European margins

(Neale, 1977; Tambareau, 1982), African and European (Donze, 1975, 1977; Babinot, 1985),

South-African and Australian (Dingle, 1982). In 1982, McKenzie proposed a paleobiogeographic

synthesis concerning the whole Tethys since the Paleozoic. Several judicious remarks and many

problems are expressed. Our contribution essentially consists of reviewing these palaeogeographical

problems during the Berriasian-Maastrichtian interval and extending these investigations to the

outer limits of the eastern Tethys as far as Australia.



Paleohiogeography of Tethyan Cretaceous Marine Ostracods 825



MAINSTYPES

OF OSTRACOD ASSOCIATIONS

:

THEIR

EVOLUTION

DURING

THE CRETACEOUS

Berriasian-Aptian (Text-fig. 1)

During this stratigraphic interval, it appears that the Berriasian has been studied more intensively. The available literature is relatively abundant, particularly for southeast France and North

Africa. For the other stages, data are much more limited.

Berriasian.- It is mainly the works of Donze (1975, 1977)which have illustrated thevery strong

ffiities existing since the uppermost Jurassic between the North African and South European

margins (southeast France, Iberian Peninsula), during the Berriasian hinge-stage between the

Jurassic and the Cretaceous. It is however, worth noticing the absence of a few “European” genera

in North Africa : Cythereis s. s., Pseudobythocythere, Kentrodictyocythere, Annosocythere. Genera

in common correspond for most of them to different species although very similar (Donze, 1977),

for example : Protocythere aff. mazenoti Donze, P . aff. revilli Donze, Oligocythereis aff. bogis

Donze. Possible migration phenomena have been proposed (Donze, 1975) through the MoroccoGibraltar-Iberian Peninsula. This opinon was later revised (Donze, 1977) with the intervention of



TEXT-FIG.l-Paleobiogeography of marine ostracods in the Tethyan Early Cretaceous (map after Barron et al.,

1981, modified; oceanic circulation after Haq, 1985). 1, Antepuijenborchella; 2, Hechticyrhere derooi or

alexanderi; 3, Majungaella.



826



Puleobiogeogruphy of Tethyun Cretaceous Marine Ostrucods 827



a possible micro-plate with shallow water paleoenvironments located at the position of the present

Alboran Sea. Data are practically nonexistent for the other sectors of the Tethyan realm.

Va1anginian.-Most studies are again limited to southeast France and are very scattered and

limited in the Iberian Peninsula. Data are available concerning India (Guha, 1976), Madagascar

(Grekoff, 1963) and Israel (Rosenfeld and Raab, 1984).

In Western Europe, associations are essentially characterized by Neocytherinae, and the genera

Protocythere s . 1. and Schuleridea. In India and mostly in Madagascar, associations are very different, peculiar with dominance of the genera Majungaelfa, Pirileberis (known since the Callovian)

and Arculicythere. These genera are essentially confined to the Southern hemisphere although

a few doubtful representatives of some of these genera (Majungaella and Arculicythere) have been

reported in the Berriasian-Valanginian of Israel (Rosenfeld and Raab, 1984).

Hauterivian-Barremian.-Ostracods of this stratigraphic interval are still very poorly known.

Data are often very scattered, imprecise and difficult to utilize. In Israel (Rosenfeld and Raab,

1984), ostracod associations, although containing so-called “austral” forms, are dominated by

genera such as Protocythere s. 1. and Schuleridea. Also to be noted is the presence of the genus

Antepaijenborchella.On the East Coast of the U.S.A. (Swain, 1981), faunas are also dominated in

marine environments by the genera Schuleridea, Asciocythere and Protocythere s. 1. Genera Hutsonia

and Fabanella in the marginal marine facies are also known in Europe (offshore Ireland, Colin

ef af., 1981).

The Barremian has been relatively well studied in the southern regions of the U.S.S.R. (Kuznetsova, 1961 ; Andreev and Mandelstam, 1971). The characteristic associations of the so-called

“Mediterranean province” are pratically generically identical to the southeastern European ones

with the genera Protocythere s . l., Eocytheropteron, Neocythere-Centrocythere, Clithrocytheridea,

Quasihermanites, Macrodentina, Annosocythere and Kentrodictyocythere. It is interesting to note

the presence of the genus Antepaijenborchella in the U.S.S.R., which is never mentioned in Europe,

but reported from the Barremian of the Persian Gulf with numerous Schuleridea and Metacytheropteron (Grosdidier, 1973).

Aptian.-Ostracod associations from the Aptian of southeast France are directly derived from

the Barremian with the same generic taxa (Oertli, 1958). Of particular note is the appearance of the

Hechticythere alexanderi-Hechticythere derooi group which has a very remarkable palaeogeographical distribution. This group, which persists into the Albian, is known in southeastern France,

the Paris basin, Great Britain, U.S.A. (Gulf of Mexico), Venezuela and Ecuador (J. P. Colin,

unpublished) and in North Africa (Bismuth et al., 1981).

As noted previously, the communications between the southern margins of the U.S.S.R. and

Western Europe are obvious. Microfauna are practically identical, particularly the genera Veenia

s. 1. and Parataxodonta. The species Parataxoxodonta uralensis Mandelstam is common to the

U.S.S.R. and to the Aptian stratotype in southeast France. A continuity at the generic level also

PLATE I-Fig. 1. Neocythere mertensi Oertli, 1958. Carapace, right lateral view, Aptian, Celtic Sea (Ireland). X 80.

Fig. 2.Schuleridea sp. Carapace, right lateral view, Aptian, Venezuela. x 81. Fig. 3. Chupmunicythereisaff.

triebeli (Mertens, 1956). Right valve, Late Cenomanian, Dordogne (S.W. France). x 70. Fig. 4. Hechticythere

cf. ulexunderi (Howe and Laurencich, 1958). Carapace, right lateral view, Aptian, Venezuela. X68. Fig. 5.

Annosocythere nudu Colin, 1974. Carapace, right lateral view, Late Cenomanian, Dordogne (S.W. France).

x 150. Fig. 6. Majunguellu perforutu Grekoff, 1963. Carapace, right lateral view, Berriasian, Majunga

(Madagascar). x 80. Fig. 7. Nigeroloxoconcha sp. Carapace, right lateral view, Senonian, Ivory Coast.

x 81. Fig. 8. Metucytheropteron berbericus (Bassoullet & Damotte, 1969). Carapace, left lateral view,

Cenomanian, Tunisia. x 81. Fig. 9. Veeniucythereisjezzineensis (Bischoff, 1963). Carapace, left lateral view,

Cenomanian, Tunisia. x 68. Fig. 10. Huughronileberis acies (Esker, 1968). Carapace, right lateral view,

Maastrichtian, El Kef (Tunisia). x 81. Fig. 11. Cophiniu cf. upifarmis (Reyment, 1960). Carapace, right

lateral view, Senonian, Algeria. x 81.



828 J.-F. BABINOT

AND J.-P. COLIN



exists in the area of Isreal and Persian Gulf. Unpublished data from Venezuela show that the

Aptian contains, in addition to Hechticythere derooi, the genera Schuleridea, Centrocythere and

Antepaijenborchella.Species of Protocythere related to Protocythere bedoulensis Moullade, originally

described from the Aptian of southeast. France, have been found in Ecuador (J. P. Colin,

unpublished). In the northwestern Atlantic (Scotian Shelf), the Aptian has yielded faunas very

similar to the European ones (Ascoli, 1976). Affinities at the specific level are known during the

entire Jurassic and Early Cretaceous.



Albian-Cenomanian (Text-fig. 2)

A1bian.-This period is particularly important for the general evolution of ostracod faunas;

termination of numerous Early Cretaceous genera and intense renewal prefiguring the Late

Cretaceous and even the Cenozoic occurred. This stage is essentially characterized by a progressive

impoverishment during the Early Cretaceous of a very flourishing family, the Protocytherinae,

progressively replaced by new Trachyleberididae genera. A similar phenomenon can be observed

for the Schulerideinae; genus Schuleridea s. s. becomes less frequent, and, in Europe, new genera

such as Dordoniella and Risaltina appear.

In Europe (including the southern U.S.S.R.), two important facts are worth mentioning:

diversification of the Pterygocythere group and the appar at the end of the Albian of the first

representatives of several genera which will strongly flourish and diversify: Mauritsina, Dumontina,



TEXT-FIQ.

2-Paleobiogeography of marine ostracods in the Tethyan Middle Cretaceous(map after Barron et al..

1981, modified; oceanic circulation after Haq, 1985). 1, Metacytheropteron berbericus-Veeniacythereis

jezzineensis; 2, Metacytheropteron minutum; 3, Arculicythere; 4, Mauritsina-Limburgina.



Pareobiogeography of Tethyan Cretaceous Marine Ostracods 829



Limburgina, Oertliella, Planileberis. Other genera, recently appeared, remain restricted to Europe;

this is the case, for example, with the Platycythereis-Chapmanicythereis group.

Since the Late Albian, North Africa and the Middle East have constituted a paleobiogeographical

entity characterized by the individualisation of very typified association with Metacytheropteron,

Veeniacythereis (e.g. V . jezzineensis) and Kamajcythereis (including Cythereis ghabounensis, in

Lebanon, Bishoff, 1963). In the Gulf of Mexico (Alexander, 1929; Moysey and Maddocks, 1982),

generic associations present real affinities with those from Western Europe with genera such as

Asciocythere, Schuleridea, and Neocythere-Centrocythere. These facts are confirmed by the DSDP

holes (Leg 14) offshore Guyana (Swain, 1976), where the African and Middle Eastern element,

Metacytheropteron minuta Swain ( M . dvoracheki Rosenfeld and Raab, 1984), is also reported.

In the northwest Atlantic region, faunas are identical, even at the specific level, with those from

northern Europe (Ascoli, 1975; J. P. Colin pers. observ.).

In Madagascar (Collignon et al., 1979), associations display a mixed character, with both genera

typically European (Dolocytheridea, Batavocythere and representatives of the Late Jurassic to

Early Cretaceous austral group : Arculicythere and Majungaella.

In southern India (Jain, 1976) and offshore Northwest Australia (Oertli, 1974) the persistence

of the genus Arculicythere is noticeable. This genus is also known in the Albian of South Africa

(Dingle, 1984). Other specific identities exist between these three regions. This, for example, is the

case for Cytherura? oertlii Dingle (Oertli, 1974; Jain, 1978). The genus Arculicythere progressively

restricts itself to a very precise area, the southeastern margin of the Tethys and the Proto-Indian

Ocean. The separation with Australia is more and more obvious with individualisation (Artesian

Basin, in Krommelbein, 1975b) of a very endemic association in which dominant genera are Allaruella, Tickalaracythere, Artesiocythere, new “Majungaella” (systematic position to be checked) and

forms related to the genus Rostrocytheridea which are known since the early Cretaceous in South

Africa and South America (Dingle, 1982).

Cenomanian.-The Cenomanian is a stage of intensive renewal already prefigured since the Late

Albian with total extinction of the Protocytheridae and explosion of the Hemicytheridae and

Trachyleberididae: Limburgina, Oertliella, Curfsina, Mosaeleberis, Mauritsina, Spinoleberis,

Trachyleberidea, Haughtonileberis, Parapokornyella, Brachycythere. This fauna persists into the

Turonian and the Senonian prefiguring Cenozoic faunas. It is very important to point out that since

this period, relations between the northern and southern margins of the western Tethys practically

cease. Two very well differentiated bioprovinces become individualised (Babinot, 1985): a west

European province with the previously mentioned genera (without Brachythere), (associations

described in the southwestern part of the U.S.S.R. are very close) and a bioprovince in North

Africa and the Middle East with predominancy of the genera Brachycythere, Protobuntonia,

Reticulocosta, Peloriops, the Veeniacythereis-Glenocythere group, Nigeroloxoconcha, and in the

marginal marine facies, Perissocytheridea. Strong, affinities exist with the West African coastal

basins (Grosdidier, 1979), indicating the possibility of trans-Saharn epicontinental marine seaway

(Reyment, 1980). Recent studies have shown an extension of the so-called “maghrebian” and

Middle-Eastern faunas to East Africa, Ethiopia, Somalia (J. P. Colin, pers. observ.) and Oman

(Babinot, pers. observ.). In Tanzania (Bate and Bayliss, 1969), some elements known in the Persian

Gulf are present, such as Cythereis lindiensis. Amphicytherura distincta, originally described from

Israel, has even been found in Mozambique (J. P. Colin, pers. observ.). In the western Atlantic

coastal plain and in the Gulf of Mexico (Alexander, 1929; Swain and Brown, 1972; Neale, 1977),

associations still have a North European generic outlook with the genera Cythereis s. I., Schuleridea

and Hazelina.

Data concerning the southeastern Tethys and its austral limits are too scattered to be used

accurately.



830



Paleobiogeography of Tethyan Cretaceous Marine Ostracods 831



Turonian-Senonian (Text-fig. 4)

Turonian.-This stage is essentially characterized by the persistence of the generic associations

established during the Late Albian and the Cenomanian. The Early Turonian is, however, marked

by a drastic impoverishment of the faunas most likely related to the strong and rapid global eustatic

sea-leveI rise (Hancock and Kaufmann, 1979) which modified the paleogeographic framework

with the disappearance of many carbonate platform environments. At the same time, anoxic facies

develop (Jenkyns, 1980; Haq, 1984), and facies with rudists and larger foraminifers disappear.

In North Africa and the Middle East, the differentiation with the Cenomanian is well marked:



TEXT-FIG.

3-Paleobiogeography of marine ostracods in the Tethyan Late Cretaceous (Senonian) (map after

Barron et al., 1981, modified; oceanic circulation after Haq, 1985). 1, Brachycythere; 2, BuntonioOvocytheridea-Cophinia ; 3, Fissocarinocythere-Ascetoleberis; 4, Mauritsina-Limburginu.



PLATE2-Fig.



1. Brachycythere sp. Carapace, right lateral view, Senonian, Algeria. ~ 8 1 Fig.

.

2. Buntoniu

opulenta Apostolescu, 1963. Carapace, right lateral view, Senonian, Senegal. X 81. Fig. 3. Aphrikunecythere

phumatoides Damotte and Oertli, 1982. Left valve, Maastrichtian, Le Kef (Tunisia). x 81. Fig. 4. Protobuntoniu

sp. Carapace, right lateral view, Senonian, Algeria. x 60. Fig. 5. Paracaudites (Dumontinu) puncturuta

(Bosquet, 1854). Carapace, right lateral view, Upper Campanian, Dordogne (S.W. France). X 81. Fig. 6.

Limburgina sp. Carapace, right lateral view, Senonian, Algeria. x 81. Fig. I. Dordoniella stranguluta Apostolescu, 1955. Carapace, right lateral view, Upper Cenomanian, Dordogne (S.W. France). ~ 8 1 Fig.

.

8,

Mauritsina cf. hieroglyphica (Bosquet, 1847). Right valve, Late Campanian, Dordogne (S.W. France). X 80.

Fig. 9. Haplocytheridea renfroensis Crane, 1965. Left valve, Winona Formation, Alabama, U.S.A. X 81.

.

11.

Fig. 10. Nigeria arachoides (Berry, 1925). Right valve, Navarro Formation, Texas, U.S.A. ~ 8 1 Fig.

Fissocarinocytherepidgeoni (Berry, 1925). Right valve, Winona Formation, Alabama, U.S.A. X 81. Fig. 12.

Antibythocypris gooberi Jennings, 1936. Right valve, Prairie Bluff, U.S.A. X 81.



832 J.-F. BABINOT

AND J.-P. COLIN



total disappearance of the Veeniacythereis jezzineensis-Glenocythere Metacytheropteron group,

and development of the genera Brachycythere and Ovocytheridea, which continue during the r e

maining part of the Late Cretaceous in Africa. The genus Brachycythere will later have a very

wide paleobiogeographical repartition to Tanzania, Mozambique, India and North and South

America (Brazil, Surinam, Ecuador).

Senonian (Text-fig. 3).-In southern Europe (including southern U.S.S.R.), associations remain practically unchanged at the generic level. Faunal differences remain important between the

northern and southern margins of the western Tethys. The few genera in common are generally

in the deep environments - Phacorhabdotus and Trachyleberidea. In North Africa, several types

of associations characterise different environments. On the platform, faunas remain typically

“African” with the genera Cophinia, Ovocytheridea, Buntonia, Protobuntonia and Veenia.

In outer-neritic environments and basins, there appear new genera such as Doriclythereis,

Megommatocythere, Kejiella, Aphrikanecythere, Palaeocosta (Donze et al., 1982). Most of these

genera persist into the Paleocene and Early Eocene in North Africa, Saharan West Africa, Saudi

Arabia and Pakistan (Siddiqui, 1971; A1 Furaih, 1980).

In the African framework, it is interesting to note an accentuation of the north-south relations,

especially on the eastern margins. This is, for example, the case for the genus Haughtonileberis,

also present in the Senonian of Algeria (Viviere, 1985). Some elements are common with South

Africa (relations with Tanzania, in Dingle, 1982, p. 384).

Morphological convergences between isochronous, but geographically separated, genera are

also noticeable; Kejiella in North Africa, Dutoitella in South Africa and Atlanticythere in the

deep South Atlantic.

Concerning India, Jain (1975) reports Neocytherinae and the genus Brachycythere in the northwest (Jain, 1977), north-Tethyian affinities are rather obvious with the presence in the Maastrichtian of a fauna very similar to that of Maastricht (Deroo, 1966), with genera such as CurJsina,

Limburgina, Murrayina, Dumontina, Echinocythereis and probably Mauritsina.

In Australia, the works of Neale (1975, 1976) and of Bate (1972) provide a tremendous amount

of information, includinp five main-points which must be emphasized:

A cosmopolitan stock with Cytherella, Cytherelloidea, Eucytherura, Hemiparacytheridea, Hermanites, Cuvsina and Oertliella.

An endemic stock with Anebocythereis, Apateloschizocythere, Eorotundracythere, Hystrichocythere, Paramunseyella, Premunseyella, Scepticocythereis, Toolongella,’Ginginella, Hemingwayella,

Rayneria and Verseya. Older genera, relics of the South Africa-Madagascar entity, Majungaella

and Rostrocytheridea persist.

Apparition of the genera Munseyella and Cytheralison which will later spread out of this geographic area. The first in the Cenozoic of Japan, South America and Gulf of Mexico, the second restricted to Australasia.

Total absehce of the North and West African genera Brachycythere, Buntonia, Ovocytheridea,

Cophinia, and Nigeria.

Here also, cases of homeomorphy have been reported (Bate, 1972)between Apateloschizocythere

and Schizocythere, Hystrichocythere and Echinocythereis, Majungaella and Neocythere-centrocythere (Krommelbein, 1979).

Dingle (1982) demonstrated that some generic affinities existed during the Santonian-Campanian between South Africa and Australia (Rayneria. Apateloschizocythere).

In North America, in the Gulf of Mexico (Hazel and Brouwers, 1982), a certain endemism is

present. One can see the apparition of new genera such as Fissocarinocythere, Ascetoleberis,

Escharacytheridea,and Antibytocypris. There are very few genera in common with the European area

of the Tethys, except perhaps a few forms attributed to the genera Trachyleberidea, Limburgina,



Paleobiogeography of Tethyan Cretaceous Marine Ostracods 833



Pterygocythere and Neocythere. Few affinities are also detected with North and West Africa with

the genera Veenia and Brachycythere. Cytherideinae are also represented by numerous species of

Haplocytheridea which will remain very common in shallow water environments during the Cenozoic. The genus Buntonia will appear only during the Paleogene.

In the Campanian-Maastrichtian of Cuba (Ljubimova and Sanchez-Arango, 1974), ostracod

associations are similar to the ones of the Gulf of Mexico, particularly the genera Brachycythere,

Ascetoleberis and Neocythere. Similar associations are also found in the northwestern Atlantic

province (Scotian Shelf: Ascoli, 1975).



PALEOBIOGEOGRAPHIC

IMPLICATIONS

/ BIOPROVINCES

From the observations made in the previous chapter, it is possible to deduct certain conclusions

of paleobiogeographical order and in particular, to recognize several ostraqod bioprovinces whose

dynamics can be followed during the Cretaceous (Text-fig. 4).

In the Early Cretaceous, and especially during the Berriasian, it is too early to speak of well

individualised bioprovinces, although a separation between the African and European margins may

already exist. The rare closely related species would testify for the existence of epicontinental communications (Donze, 1975, 1977) despite a certain time lag affecting the apparition of some species,

generally more precocious in North Africa, since the Early Jurassic. From the Valanginian to the

Aptian, a bioprovince with numerous genera in common corresponding approximately to the

Caribbean and Mediterranean provinces becomes individualised. It is essentially characterized by

the genera Protocythere s. l., Schuleridea, Neocythere-Centrocythere, Rehacythereis. In the southern

part of this entity, from the Middle-East (Israel) to North Africa and even to Venezuela, a latitudinal province characterized by the genus Antepaijenborchella is superimposed. The southern part

of the U.S.S.R.(Mediterranean realm sensu lato) (Andreev and Mandelstam, 1971) belongs to

this last paleobiogeographic entity. In the Southern hemisphere, another province becomes

differentiated with the dominant genera Majungaella, Pirileberis and Arculicythere (Madagascar,

India, South Africa, Argentina). This bioprovince is situated on the extreme border of the Tethyan

realm.

During the Albian and mainly the Cenomanian, the separation between the northern (European)

and southern (African) margins becomes total. A very homogenous (even at the specific level) province is formed, which comprises the whole of North Africa, the northern part of East Africa

(Somalia, Ethiopia) and the Middle East to the Persian Gulf (Babinot, 1985), which can be called

“bioprovinces of Veeniacythereis jezzineensis and Metacytheropteron berbericus. ” As pointed out

by Bismuth et al. (1981), this fits well into the recent models of global tectonics. These models

show that the Tethys, a deep-sea realm that may constitute a significant enough obstacle to prevent

exchanges of benthic faunas, includes northern littoral domains (Euroasiatic plates) and southern

litoral domains (African plate and its Arabic and Italian promontories).

It is still too early to define the north-European Tethyan province, our knowledge being limited

to southern France and the Iberian Peninsula (Spain and Portugal). This southwestern European

bioprovince (Babinot, 1985) is, however, well characterised and differentiated from the NorthAfrican and the more boreal north-European provinces. Characteristic genera are mainly Mauritsina and Limburgina. The generic content of this province will evolve very slowly during the Late

Cretaceous.

During the Albian, North America is still very poorly differentiated from northern Europe at the

generic level, but the separation is effective at the specific level in the Gulf of Mexico, whereas faunas

of the Canadian continental shelf are very closely related to the north-European faunas. During the



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Chapter 58. Palaeogeography of Tethyan Cretaceous marine ostracods.

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