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Chapter 58. Palaeogeography of Tethyan Cretaceous marine ostracods.
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
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
OF OSTRACOD ASSOCIATIONS
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.
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,
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
Data concerning the southeastern Tethys and its austral limits are too scattered to be used
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:
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.
1. Brachycythere sp. Carapace, right lateral view, Senonian, Algeria. ~ 8 1 Fig.
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.
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.
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).
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
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
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
Brachycythere Buntonia/Protobuntonia Reticulocosta
Ovocytheridea/Cophinia Nheria Haughthonileberis
Ascetoleberis - Haplocytheridea
I- - -- - - -
-Schulerideinae- Protocytherinae Neocythere/Centrocythere
VALANGINIEN Kentrodrtyocythwe/ I
AEvoIution of ostracod faunas in the Tethyan paleobiogeographic provinces during the Cretaceous.