lower cretaceous pelagic to hemipelagic sediments cover relatively small , restricted areas in the higher dolomites ( southern alps ) . in the southern alps , cephalopod - bearing deposits are mainly recorded in two different facies ( lukeneder , 2010 ) , the calcareous limestones of the biancone formation (=  maiolica formation in the appenines ; see weissert , 1981 ) and the more marly puez formation ( lukeneder , 2010 ) . the stratigraphy of the lower cretaceous puez area is based on microfossils , nannofossils and ammonites ( lukeneder and aspmair , 2006 , lukeneder , 2010 ) , but a detailed ammonite biostratigraphy and zonation was still missing because ammonites have not been collected bed - by - bed over the last 150 years . this paper presents the results of the systematic ammonite sampling at the puez section and concludes with a detailed ammonite zonation of that locality . the mediterranean character of the ammonite fauna is comparable to numerous lower cretaceous east - central european ( czech republic , france , hungary , slovakia , spain ) , eastern europe ( bulgaria , rumania ) and african ( algeria , morocco ) localities . the main goal of this paper is to present a valid definition of the lower cretaceous ammonite zonation within the dolomites for the puez formation . the hauterivian and barremian ammonite faunas from the puez key - section can be correlated with the most recent ammonite standard zonation for the lower cretaceous ( reboulet et  al . , 2009 ) . future work will involve palaeomagnetic , isotope and geochemical analyses along with a precise biostratigraphy based on macro- , micro- and nannofossils . the outcrop is situated on the puez - odle - gardenaccia plateau in the dolomites ( maps trentino  alto adige ; south tyrol ; lukeneder , 2010 ) . the grey , green to red succession of the puez formation is located on the southern side of the piz de puez . the studied sites are outcrops on the puez - gardenaccia plateau ( lukeneder , 2010 ) . they are located within the area of the puez - odle - geisler natural park in the northern part of the dolomites . the dolomites ( permian  cretaceous ) are an internal part of the southern alps ; they are a northern italian chain that emerged during the deformation of the passive continental margin of the adriatic (=  apulian plate ) of the south alpine apennine block ( dercourt et  al . , 1993 , fourcade et  al . , 1993 , bossellini , 1998 , cecca , 1998 , stampfli and mosar , 1999 , scotese , 2001 , stampfli et  al . , 2002 , bosellini et  al . , 2003 ) this block was limited by the penninic ocean (=  alpine tethys ) to the north and the vardar ocean to the southeast ( scotese , 2001 , stampfli et  al . , 2002 ) . the puez formation comprises three members from bottom to top : puez limestone , puez redbed and puez marl ( lukeneder , 2010 ) . the succession shows a transition from limestones and marly limestones into a marl  marly limestone alternation in the upper half of the section . a detailed description of the geology and lithostratigraphy is given in lukeneder ( 2010 ) . the complex mediterranean palaeogeography , and the presence of microplates in the tethyan oceanic corridor between africa and europe , was discussed in detail in lukeneder , 2010 , lukeneder , 2011 . the trento plateau extends from the south ( around trento ) up to the puez region and was formerly surrounded by two basins : the lombardian basin to the west and the belluno basin to the east ( lukeneder , 2010 ) . according to recent investigations by muttoni et  al . ( 2005 ) , the lombardian basin , and thus the adjacent trento plateau to the east , were located at approximately 20n in valanginian during the late 19th and early 20th centuries , a rich fauna of cephalopods was collected from lower cretaceous sediments from this area by haug , 1887 , haug , 1889 , hoernes , 1876 , uhlig , 1887 , rodighiero , 1919 and pozzi ( 1993 ) . additionally , microfacies and ammonites were reported from the  alpe puez  by cita and pasquar ( 1959 ) and cita ( 1965 ) , leading them to assume a hauterivian after this period , documented by numerous publications on the ammonite fauna of the puez and adjacent areas by the latter authors , no further investigations were undertaken at the main locality of puez . this phase of stagnancy in lower cretaceous papers was followed by descriptions of small ammonoid faunas from different localities near the puez area , e.g. , from la stua by baccelle and lucchi - garavello ( 1967 ) and sthr , 1993 , sthr , 1994 . the latter papers compared the faunas from la stua with the puez ammonite faunas from haug , 1887 , haug , 1889 and uhlig ( 1887 ) . the most recent contributions on the lower cretaceous of the puez area were published during the last decade and focused on stratigraphy ( lukeneder and aspmair , 2006 ) , palaeoecology ( lukeneder , 2008 ) and lithostratigraphy ( lukeneder , 2010 , lukeneder , 2011 ) . the ammonites originate from the puez locality ( dolomites ; fig .  1 ) . bed - by - bed collecting and a systematic - taxonomic study provide the basic data for statistical analysis of the investigated ammonite fauna . the material was collected over the last 3 years within the fwf project p20018-n10 and is stored in the south tyrol museum of natural sciences and the natural history museum in vienna . the preservation of the ammonites is fair ( mostly compressed steinkerns without shell ) and represents almost the totality of the macrofauna ( 96% ) . approximately 1209 ammonites , 6 nautilids , 10 lamellaptychi , 6 belemnites , 150 sea urchins , 40 bivalves , 39 brachiopods , and abundant encrusting species ( bivalves , corals , serpulids ; lukeneder , 2008 ) were examined . upper barremian genera : phylloceratidae with phylloceras , phyllopachyceras , sowerbyceras ; lytoceratidae with lytoceras , eulytoceras , protetragonites ; desmoceratidae with plesiospitidiscus , barremites , valdedorsella , abrytusites , ? pseudohaploceras , melchiorites ; silesitidae with silesites ; holcodiscidae with astieridiscus , holcodiscus , maurelidiscus ; pulchelliidae with gerhardtia , heinzia , kotetishvilia , discoidellia ; haploceratidae with neolissoceras ; crioceratidae with crioceratites , pseudothurmannia , paracostidiscus ; emericiceratidae with emericiceras , honnoratia , paraspiticeras ; acrioceratidae with acrioceras , dissimilites ; ancyloceratidae with toxancyloceras , audouliceras ; heteroceratidae with moutoniceras ; leptoceratoididae with karsteniceras , hamulinites , sabaudiella ; ptychoceratidae with ptychoceras ; hamulinidae with hamulina , anahamulina , vasicekina , ptychohamulina , duyeina ; megacrioceratidae with megacrioceras ; macroscaphitidae with macroscaphites , costidiscus . conventions . , 1996 , klein , 2005 , vermeulen and klein , 2006 and klein et  al . the detailed ammonite systematics and taxonomy were adopted and correlated with papers by numerous authors cited in section 5 below . the ammonite species and resulting ammonite zones indentified herein for the puez formation allow a correlation of the hauterivian and barremian strata at the puez locality with the recent standard zonation ( reboulet et  al . , 2009 ) . the ammonite zonation established by the cretaceous ammonite working group (  kilian group  ) at the international meeting on lower cretaceous ammonite zonation in vienna ( reboulet et  al . , 2009 ) is followed . hoedemaeker and rawson , 2000 , hoedemaeker et  al . , 2003 and reboulet et  al . ( 2006 ) have been considered for correlation of former and recent literature zonations . if a particular zonal index ammonite is absent the zonal boundary is interpreted by comparison with faunas that characterize the zone elsewhere . the idea of a pseudothurmannia mortilleti subzone ( middle subzone within the  pseudothurmannia ohmi  zone ) is accepted . p.  mortilleti was meant to be a senior synonym of pseudothurmannia catulloi ( company et  al . , 2003 , company et  al . , 2005 , company et  al . , 2008 ) . a scheme is , therefore , followed that includes a p.  mortilleti subzone ( fig .  2 , fig .  3 , fig .  5 , fig .  7 ) . the scheme including a p.  catulloi subzone as in reboulet et  al . the biostratigraphy is compared to sections in europe ( abridgded list ) from the northern calcareous alps of austria ( immel , 1978 , immel , 1987 , vaek and faupl , 1999 , lukeneder , 2003 , lukeneder , 2004a ) , the gerecse and bakony mountains in hungary ( janssen and fzy , 2005 ; fzy and janssen , 2009 , fzy and janssen , 2006 ) , the balkan mountains of bulgaria ( dimitrova , 1967 , mandov , 1976 ) , the silesian units within the western carpathians and pieniny klippen belt of czech republic and slovakia ( uhlig , 1883 , vaek , 1972 , vaek , 1994 , vaek , 1996 , vaek , 2002 , vaek , 2008 , vaek et  al . , 2004 , vaek and michlik , 1999 ) , the southern alps of northern italy and umbria - marche apennines of central italy ( uhlig , 1883 , uhlig , 1887 , haug , 1887 , haug , 1889 , rodighiero , 1919 , cecca and pallini , 1994 , cecca et  al . , 1994a , cecca et  al . , 1994b , cecca et  al . , 1995 , cecca et  al . , 1996 , 1996 ) , different districts around the vocontian basin of southeast france ( pictet and loriol , 1858 , lory and sayn , 1895 , busnardo , 1965 , busnardo , 1984 , thomel , 1964 , autran , 1993 , delanoy , 1994 , delanoy , 1997 , vermeulen et  al . , 1999 , vermeulen et  al . , 2002 , vermeulen , 2002 , vermeulen , 2005a , vermeulen and lazarin , 2007 , bert et  al . , 2008 , vermeulen , 2008 , vermeulen , 2009a , vermeulen , 2009b ) , the south and east carpathians of romania ( avram , 1990 , avram , 1994 , avram , 2001 , patrulius and avram , 2004 ) , the betic cordillera in southeast spain ( barga et  al . , 1982 , aguado et  al . , 1992 , aguado et  al . , 2001 , company et  al . , 2008 , hoedemaeker , 1994 ) and the swiss alps and ultrahelvetic units of switzerland ( ooster , 1860 , sarasin and schndelmayer , 1901 , sarasin and schndelmayer , 1902 , busnardo et  al . , 2003 ) . the biostratigraphy is compared with sections in north africa : algeria ( vermeulen and lahondre , 2008 ) and morocco ( company et  al . , 2008 ) . the biotratigraphic zonation at puez ranges from the upper hauterivian balearites balearis zone up to the upper barremian gerhardtia sartousiana zone ( fig .  2 , fig .  3 , fig . not every standard zone or subzone could be detected at the locality using index ammonite species . the balearites balearis zone is divided into the balearites balearis , binelliceras binelli , crioceratites krenkeli and spathicrioceras seitzi subzones ( reboulet et  al . , 2009 ) : for correlation , see also company et  al . , 2002 , company et  al . , 2003 . the b.  balearis zone is the oldest ammonite zone detected at puez , where the succession begins within the b.  binelli subzone . the dominance of the family crioceratidae ( e.g. , crioceratites and pseudothurmannia ) hints at the upper hauterivian . 4h ) and plesiospitidicus strengthens the upper hauerivian age for the lowermost parts of the puez formation at puez ( fig . the b.  binelli subzone is not indicated by the index species but occurs with the family phylloceratidae comprising phylloceras tethys and phyllopachyceras winkleri . the b.  binelli subzone is defined here to be located below the c.  krenkeli subzone and characterized by the absence of c.  krenkeli . the c.  krenkeli subzone begins with the first appearance of c.  krenkeli within bed p1/21 ( fig .  3 ) . the abundance of the index ammonite c.  krenkeli and the co - occurring ammonite assemblage in beds p1/21 up to bed p1/44 hint at the presence of the c.  krenkeli subzone . the c.  krenkeli subzone is dominated by the index ammonite c.  krenkeli ( fig . 4a  c ) and is accompanied by p.  radians , anahamulina jourdani ( fig .  4 m ) , p.  tethys , phyllopachyceras infundibulum ( fig . ( 2009 ) , b.  binelli and c.  krenkeli occur only in the uppermost part of the b.  balearis zone , which is characterized by the range of the index species . the uppermost subzone within the b.  balearis zone , the sp . seitzi subzone , could not be determined so far based on the zonal index ammonite . its base is tentatively located at the base of bed p1/44 ( fig .  2 , fig .  3 , fig .  4 ) . beds within the b.  balearis zone display relatively low numbers of species per bed from one to four . the same numbers are shown in families per bed , with lower numbers in the lower parts increasing to the top of the zone ( fig . the mean number of families in the b.  balearis zone is five , the maximum is eight within the c.  krenkeli subzone . the evaluation of biodiversity calculated from the ratio between number of species vs. number of individuals per species , the shannon index , shows a mean value for the b.  balearis zone of 0.84 ( min . 0.5 , max . 1.8 ; this indicates a low species richness and low evenness in their abundance ( fig . ( 2003 ) reported a more intense ammonite diversification and increased abundance in several ammonite groups for upper hauterivian faunas within the zone from the betic cordillera compared to the subzones below ( e.g. , c.  balearis and c.  binelli subzones ) . ( 2003 ) broadly correlate with the data presented herein and show that the c.  krenkeli zone is characterized by the occurrence of the index  ammonites c.  krenkeli , crioceratites majoricensis , a.  jourdani , n.  subgrasianum , p.  subdifficilis , a.  neumayri , p.  guerianianum , d.  vermeuleni , l.  subfimbriatum , p.  tethys , p.  winkleri and p.  infundibulum . the same faunal compositions were shown by fzy and janssen , 2009 , fzy and janssen , 2006 within their crioceratites / pseudothurmannia assemblage for the b.  balearis zone from the gerecse mountains in hungary . the b.  balearis zone embraces , according to these authors , phylloceras infundibulum (=  phyllopachyceras infundibulum ) , phylloceras sp . , lytoceras sp . , plesiospitidiscus spp . and typically crioceratites sp . accompanied by c.  krenkeli . the same condition can be recognized in the more southwestern bakony mountains of hungary ( fzy and janssen , 2006 ) with p.  tethys , p.  infundibulum , p.  winkleri , l.  subfimbriatum , neolissoceras grasianum , abrytusites ssp . , p.  subdifficilis , c.  krenkeli , p.  radians , silesites ssp . and discoidellia favrei . this assemblage is equivalent to the fauna corresponding to the interval of the b.  balearis zone ( c.  krenkeli subzone ) and data from puez correlate with reported upper hauterivian assemblages from the northern calcareous alps in austria comprising p.  subdifficlis , p. cf . doubleri , l.  subfimbriatum , p.  tethys and p.  infundibulum ( vaek and faupl , 1999 ) . the same situation was shown from the northern calcareous alps by lukeneder ( 2003 ) , who established a c.  krenkeli - abundance zone similar to the c.  krenkeli beds of puez comprising also abundant species such as c.  krenkeli , p.  infundibulum and l.  subfimbriatum . vaek ( 1999 ) reported m.  doubleri from beds of the subsaynella sayni or p.  ligatus zone from the northern calcareous alps in austria , and therefore appearing earlier than at puez , where it appears in the b.  balearis zone . ( 1987 ) designated this new genus megacrioceras ( e.g. , m.  doubleri ) for this upper hauterivian form of ptychoceratoidae . they assumed a range for the taxon in southeast france from the s.  sayni zone to the p.  angulicostata zone . ( 1994 ) in silesian units of the western carpathians , showing the same dominance in pseudothurmannia . zones (=  euptychoceras borzai and c.  binelli zones in vaek et  al . , 1994 ) . autran ( 1993 ) reported faunas from the upper hauterivian of the castellane region ( southeast france ) by referring to ammonite zonations as h6 ( b.  balearis zone ; see busnardo , 1984 ) and h7 ( p.  ohmi zone ) . h6 was characterized by the assemblage of p.  infundibulum , l.  subfimbriatum , acrioceras sp . paraspiticeras sp . , m.  doubleri and p.  favrei (=  d.  favrei ) . upper hauterivian faunas from the historic veveyse de chtel section (  ultrahelvtique des pralpes externs  ) in switzerland were reinvestigated by busnardo et  al . the fauna of the equivalent b.  balearis zone comprises p.  tethys , p.  infundibulum , p.  winkleri , l.  subfimbriatum , lytoceras sp . and the upper boundary of the comparable b.  balearis zone at puez could not be attributed to a single bed and is tentatively located within bed p1/47 . avram ( 1994 ) reported two different and specifiable pseudothurmannid assemblages for the south carpathian region around svinia . the lower one is with pseudothurmannia pseudomalbosi from the b.  balearis / p . ohmi zone boundary , and the upper is characterized by the mixed assemblage of p.  angulicostata , p.  picteti and p. cf . catulloi (=  junior synonym of p.  mortilleti ; see company et  al . , 2003 , company et  al . , 2008 ) accompanied by the first paraspiticeras specimens , making it comparable to the p.  picteti zone at puez ( fig .  3 , fig .  4 ) . avram ( 1994 ) also noted the presence of the first d.  favrei (=  avram s psilotissotia favrei ) within the first levels above the pseudothurmannia beds . d.  favrei starts at puez with p.  pseudomalbosi within the p.  mortilleti zone . the accompanying lytoceratid and phylloceratid faunas are equivalent in both areas , i.e. , svinia and puez . at the puez section it is tentatively located at the base of bed p1/47 ( fig .  2 , fig .  3 , fig .  4 ) . zone reaches up to bed p1/86 ( fig .  2 , fig .  3 ) . its base is tentatively located at bed p1/47 and its upper boundary is assigned to be at the top of the last bed before the overlying pseudothurmannia mortilleti subzone . subzone ) is characterized by the presence of pseudothurmannia sp . , karsteniceras sp . and sabaudiella simplex ( fig . the p.  mortilleti subzone starts with the first appearance of p.  mortilleti at bed p1/50 ( fig . this appearance coincides at the puez locality with the last occurrence of c.  krenkeli . p.  mortilleti typically co - occurs with p.  pseudomalbosi from beds p1/50 up to p1/58 ( fig . the p.  mortilleti subzone from beds p1/50 to p1/65 comprises a characteristic ammonite association of p.  mortilleti , p.  pseudomalbosi , honnoratia thiollierei ( fig . 4j , k ) , hamulina sp . , anahamulina sp . , hamulinites munieri ( fig .  4p ) p.  subdifficilis and plesiospitidiscus sp . the subzone is also marked by the first occurrence of the family pulchelliidae with d. cf . p.  tethys , p.  infundibulum , l.  subfimbriatum , lytoceras sp . , and the p.  picteti subzone starts with its index species p.  picteti from bed p1/66 and reaches up to the end of the p.  picteti subzone , thus to the end of the  ps . the p.  picteti subzone is characterized by the association of p.  picteti ( fig . additionally , representatives of the families phylloceratiodae and lytoceratidae occur with p.  tethys ( fig . 4y ) , phylloceras sp . , p.  infundibulum , l.  subfimbriatum , l.  anisoptychum ( fig . haploceratidae show their last members with n.  subgrasianum within the p.  picteti subzone . bed p1/86 therefore tentatively marks the upper boundary of the hauterivian . beds within the  pseudothurmannia ohmi  zone display numbers of species per bed from one to nine . thirteen families occur within the zone with numbers per bed from zero to ten , with highest values in the p.  mortilleti and p.  picteti zones ( fig . the mean number of families in the b.  balearis zone is 8.6 , the maximum is twelve within the p.  picteti subzone . this indicates a higher species richness ( e.g. , twice ) than is seen in the b.  balearis zone ( fig . the p.  ohmi zone with the p.  ohmi , p.  catulloi or p.  mortilleti and p.  picteti subzones are as proposed by company et  al . p.  mortilleti was meant to be a senior synonym of p.  catulloi ( company et  al . , 2003 , company et  al . , 2008 ) . ( 2008 ) established a scheme with a p.  mortilleti zone , which is followed herein ( fig .  2 , fig .  3 , fig .  5 , fig .  7 ) . ohmi  zone in the gerecse mountains in hungary similar faunas to those of puez , dominated by p.  infundibulum , phylloceras sp . similar to the first appearance of d.  favrei at puez within the p.  mortilleti subzone , vermeulen ( 2002 ) reported first appearances of d.  favrei and psilotissotia sp . at angles ( barremian stratotype ; alpes de haut - prevence , southeast france ) from the same subzone , and additional occurrences within the p.  picteti subzone . equivalent faunas were reported from upper hauterivian sections of ro argos section in southeast spain by hoedemaeker ( 1994 ) . he reported assemblages with p.  tethys , p.  winkleri , l.  subfimbriatum , n.  subgrasianum , d.  favrei , p.  mortilleti , p.  catulloi  , p.  subdifficilis , c.  krenkeli and first appearances of l.  densibfimbriatum , p.  crebrisulcatus , s.  vulpes , paraspiticeras spp . and h.  thiollierei ( hoedemaeker s emericiceras thiollierei ) at the top of hoedemaeker s  pseudothurmannia catulloi zone (=  top of p.  picteti zone in reboulet et  al . , ( 2007 ) , honnoratia honnoratiana and h.  thiollierei are the same species ; hence , h.  thiollierei is the senior synonym and has priority . h.  thiollierei and paraspiticeras first occur at puez within the p.  mortilleti zone . ( 1982 ) from the jan province ( betic cordillera ) , comprising similar components to those of puez with p.  mortilleti , a.  tabarelli and first appearances of d.  favrei (=  p.  favrei in barga et  al . , 1982 ) within their p.  ohmi  auct . zone and the p.  mortilleti zone of reboulet et  al . zone , which corresponds to the upper part of the b.  balearis zone ( i.e. , c.  krenkeli subzone ) of reboulet et  al . vaek ( 1994 ) reported d.  favrei (=  vaek s p.  favrei ) from the p.  angulicostata zone of the western carpathians ( czech republic and slovakia ) , which is equivalent to the more recently established d.  favrei derives most probably from the p.  mortilleti subzone because he gave the exact range of the appearance of his p.  mortilleti (=  p.  catulloi ) . cecca and pallini ( 1994 ) detected several assemblages from the umbria - marche apennines ( central italy ) with co - occurrences of p.  mortilleti catulloi and d.  favrei (=  cecca and pallini s p.  favrei ) . they assumed the fauna to be uppermost hauterivian ( i.e. , former p.  angulicostata auct . zone , now p.  ohmi auct . zone and p.  mortilleti subzone ; reboulet et  al . , 2009 ) . the subspecies name of p.  mortilleti catulloi given by cecca and pallini ( 1994 ) once again shows the confusion within the determination of the members of the pseudothurmannia group , which is also evident for example in hoedemaeker , 1994 , vermeulen et  al . , 2002 and company et  al . some species determinations made by cecca and pallini ( 1994 ) seem to be incorrect ( see also vermeulen and klein , 2006 ) because m.  moutonianum can not occur with or above silesites seranonis and gerhardtia provincialis (=  cecca and pallini s heinzia provincialis ) . uppermost hauterivian faunas from the maiolica formation of the lessini mountains and central apennines ( northeastern and central italy ) were reported from faraoni et  al . , 1995 , these faunas were regarded as having been deposited within a guide level , the so - called mediterranean faroni level ( see also galeotti , 1995 , baudin et  al . , 1997 ) within the p.  ohmi auct .  zone ( i.e. , p.  catulloi subzone  =  p.  mortilleti subzone ) . assemblages include the same members as seen at puez with p.  infundibulum , e.  anisoptychum , p.  catulloi , p.  favrei (=  d.  favrei ) , plesiospitidiscus sp . and e.  thiollieri (=  h.  thiollierei ) . ( 1994 ) , the transitional interval between uppermost hauterivian and lower barremian strata in southeast spain is often missing or condensed , depending on the palaeogeographic position during that time . condensation in deeper environments and concurrent erosion and manifestation of hiatuses were detected in southeast spain ( company et  al . , 1994 ) . as they showed in the sierra del corque ( capres section cp2 ; company et  al . , 1994 ) , a total loss of sediments from the upper hauterivian ( b.  balearites zone ) up to the holcodiscus caillaudianus zone ( sea - level rise ) occurs . this fits well with the condensed lower lower barremian succession at puez , which needs more detailed sampling . the kilian group replaced the h.  callaudianus zone by the topmost m.  moutonianum zone ( hoedemaeker and rawson , 2000 ) . ( 2003 ) described typical assemblages for the p.  mortilleti zone , namely the occurrence of p.  mortilleti , p.  pseudomalbosi , e.  thiollierei (=  h.  thiollierei ) , acrioceras meriani , anhamulina subcylindrica , p.  subdifficilis , a.  neumayri , p.  guerianianum , first d.  favrei , l.  densfimbriatum , p.  tethys , and p.  infundibulum . as they noted , a prominent faunal turnover or renewal takes place within that zone , often referred to as the mediterranean faroni level ( faraoni et  al . , 1995 , faraoni et  al . , 1996 , galeotti , 1995 , baudin et  al . , 1997 , ( 2003 ) described typical assemblages for the p.  picteti zone , namely the occurrence of p.  picteti , e.  thiollierei (=  h.  thiollierei ) , acrioceras ramkrishnai , paraspinoceras morloti , a.subcylindrica , hamulinites munieri , and in  the lower parts , the last specimens of p.  subdifficilis and a.  neumayri , barremites ssp . , first appearances of silesites sp . , p.  guerianianum , d.  favrei , l.  densifimbriatum , first members of p.  obliquestrangulatum , p.  tethys , and p.  infundibulum . company et  al . ( 2005 ) discussed faunal changes linked to the faraoni level of the betic cordillera . they showed that the ammonite faunal changes ( e.g. , renewal ) from hauterivian to a more barremian  face  occurs stepwise during the p.  ohmi subzone / p . mortilleti boundary period , and at the base of the p.  picteti subzone and within the upper part of the p.  picteti subzone , both characterized by diversification and replacement of species . the first step occurs during a second - order peak transgression , and the second at a sea - level highstand . extinction event  marked by extinctions of several species which appeared during the first two steps ( company et  al . , 2005 ) ; this is linked to a major sea - level fall . ( 2005 ) noted the first step as being characterized by the disappearance of n.  subgrasianum , p.  infundibulum and l.  subfimbriatum around the p.  ohmi mortilleti boundary , whereas new forms from pulchelliidae ( d.  favrei ) and leptoceratoidinae ( hamulinites ) occur . at puez the situation is similar because l.  subfimbriatum disappears within the p.  mortilleti subzone , and p.  infundibulum disappears within the p.  mortilleti subzone and reappears in the p.  picteti subzone . n.  subgrasianum is very rare within the p.  mortilleti subzone , whereas hamulinites and d.  favrei first appear in this subzone . the second step is somewhat less spectacular ( company et  al . , 2005 ) , marked by species changes within genera and appearances of closely related forms at the base of the p. picteti subzone . examples include p.  mortilleti and p.  pseudomalbosi replaced by p.  picteti , acrioceras meriani by a.  ramkrishnai , and the occurrence of paraspinoceras morloti . the base of the p.  picteti subzone is characterized by the third step , which ranges more or less up to the hauterivian / barremian boundary . extinctions occur in the betic cordillera , for example , in p.  picteti , hamulinites nicklesi , anhamulina fumisugina , p.  morloti , and at puez in desmoceratidae , such as a.  neumaryi in spain and abrytusites , p.  breskovskii and p.  subdifficilis . in contrast , members of holcodiscidae as taveraidiscus in spain and maurelidiscus and astieridiscus both a puez , in addition to silesitidae with silesites occur within that interval . real  barremites dimboviciorensis in spain , and emericiceratidae occur with the last paraspiticeras guerini (=  p.  guerinianum in company et  al . , ( 2001 ) for the betic cordillera region ; this is closely similar to the most recent one by reboulet et  al . ( 2001 ) characterized the b.  balearis zone by the presence of anahamulina jourdani and rare first discoidellia . additionally , numerous specimens of p.  subdifficilis , a.  neumayri , n.  subgrasianum , l.  subfimbriatum , p.  infundibulum and p.  winkleri occur . zone  =   p.  ohmi  zone ; see reboulet et  al . , 2009 ) and decided to record a subzonation with a lower p.  ohmi , a middle p.  mortilleti and an upper p.  morloti subzone . ( 2001 ) is characterized by an assemblage with p.  ohmi , n.  subgrasianum , l.  subfimbriatum , l.  densifimbriatum and first appearances of silesites and barremites . additionally , numerous specimens of subzonal index ammonites are p. mortilleti in the middle and p.  picteti in the middle (=  p.  mortilleti subzone ) and subsequently in the upper parts (=  p.  picteti subzone ; reboulet et  al . , 2009 ) of their p.  mortilleti zone . in southeast france the main occurrences of a.  tabarelli were reported by thomel et  al . ( 1990 ) to be lower barremian , starting from the basal barremian . at puez ( 2010 ) reported simlar faunal components from the upper hauterivian of southeast france with p.  picteti and p.  pseudomalbosi , plesiospitidiscus sp . and a.  neumayri . ( 2003 ) reinvestigated and collected numerous faunas from the uppermost hauterivian from the historic veveyse de chtel section in switzerland . . , 2003 ) zone comprises p.  tethys , p.  infundibulum , l.  subfimbriatum , lytoceras sp . , plesiospitidiscus spp . , p.  guerinianum , the first abrytusites sp . , hamulina sp . , sabaudiella simplex , p.  mortilleti (=  parathurmannia mortilleti after busnardo et  al . ( 2003 ) ) , as well as the first d.  favrei and h.  thiollierei (=  h.  honnoratiana after busnardo et  al . ( 2008 ) reported uppermost hauterivian ( p.  ohmi zone ) to upper barremian ( g.  sartousiana zone ) faunas from the western high atlas . they noted that most of the logs are not complete and comprise several hiatuses and condensation phases . they showed that the p.  ohmi subzone corresponds to a tst ( transgressive system tract ) and that the p.  mortilleti subzone corresponds to the hst ( highstand system tract ) of the sequence ha6 ( the mfs , maximum flooding surface , corresponds to the base of the p.  mortilleti subzone  =  faraoni level ) . the sequence boundary ha7 is missing in most of the western high atlas localities owing to hiatuses , and followed immediately by the tst and hst of ha7 in the upper t.  hugii zone . the exact sequences at puez from t.  hugii to m.  moutonianum remain unclear , but seem quite similar . in morocco the top of t.  hugii and base of k.  nicklesi were correlated to be the lst of barr1 , but missing . the tst and hst ( upper part of k.  nicklesi zone and lower part of n.  pulchella zone ) coincided with a maxium flooding during the barremian . the k.  compressissima zone and the lower  middle part of the c.  darsi zone (=  m.  moutonianum zone ) would correspond to the tst and hst of sequence barr2 and the whole of sequence barr3 . the lst of ba4 corresponds partly to the lower part of the t.  vandenheckii zone , and the tst and maximum flooding surface ( mfs ) are represented in the g.  sartousiana zone . the end of barremian sedimentation is marked in the western high atlas by an unsynchronous late early barremian or early late barremian erosive unconformity ( see also hardenbol et  al . , 1998 , adatte et  al . , 2005 , arnaud , 2005 ) . according to data from the western high atlas of morocco ( company et  al . , 2008 ) , the p.  ohmi zone is characterized by typical faunas with p.  ohmi , p.  mortilleti , p.  pseudomalbosi , p.  subdifficilis , a.  neumayri and parspiticeras sp . , which broadly correlates with the situation at puez . by contrast to the situation with p.  picteti , the p.  picteti subzone and the lowermost part of the t.  hugii zone are missing in morocco , marked by a hiatus , and the p.  mortilleti subzone is directly overlain by lower barremian sediments . the hauterivian / barremian boundary could not be determined based on the occurrence of index ammonites , neither could the index ammonite species be detected for the t.  hugii auctorum zone or the kotetishvilia nicklesi , nicklesia pulchella and kotetishvilia compressissima zones ( see discussion ) . the ammonite zonal boundaries are therefore given tentatively ( fig .  2 , fig .  3 , fig .  6 ) . the base of the lower barremian is fixed at the bottom of bed p1/87 , which corresponds to the base of the t.  hugii auct it shows first appearences of barremites ssp . , melchiorites sp . , silesites sp . zone , the lowermost zone of the lower barremian , is marked by an increasing number of members of the family desmoceratidae . holcodiscidae show occurrences of the last astieridiscus sp . , whereas real holcodiscus appears and the  first appearance of maurelidiscus cf . the occurrence of m.  kiliani ( within the m.  kiliani zone ) was interpreted by vermeulen , 2005a , vermeulen , 2005b , vermeulen , 2009b ) to mark the basal barremian . the m.  kiliani zone after vermeulen ( 2003 ; see vermeulen , 2007b , vermeulen , 2009b ) was considered to be an equivalent of the taveraiduscus hugii zone after hoedemaeker et  al . representatives of the families phylloceratiodae ( p.  tethys , p.  infundibulum ; fig . 6u ) and lytoceratidae ( l.  densifimbriatum ) complete the ammonite assemblage of the t.  hugii auct . eight families occur within the zone with numbers per bed from zero to six , with highest values in lowermost and uppermost parts ( fig . subzone and an upper psilotissotia colombiana subzone ( reboulet et  al . , 2009 ) . rawson ( 1996 ) defined this zone and the first occurrence of t.  hugii as the base of the barremian stage . p.  colombiana was considered as an index species of the zone ( vermeulen , 1996 ) . a detailed discussion on the zone is given by company et  al . . zone in the gerecse mountains of hungary show an occurrence of p.  infundibulum , phylloceras winkleri (=  phyllopachyceras winkleri ) , phylloceras sp . , anahumulina sp . , hamulina sp . , and typically the pulchelliids d.  favrei , t.  hugii and taveraidiscus intermedius ( fzy and janssen , 2009 , fzy and janssen , 2006 ) . lowermost barremian faunas from the veveyse de chtel section in switzerland ( busnardo et  al . , 2003 ) comprise faunal equivalents of the puez t.  hugii zone with p.  tethys , p.  infundibulum , l.  subfimbriatum ; in the lowermost beds the last plesiospitidiscus and abrytusites specimens occur . h.  thiollierei shows the last occurrence in the lowermost t.  hugii beds . they designated a spitidiscus hugii zone (=  t.  hugii zone after reboulet et  al . , 2009 ) . the lower t.  hugii subzone was characterized by the presence of taveraidiscus ssp . , barremites boutini , lytoceras obliquestrangulatum (=  protetragonites obliquetsrangulatum ) , hamulina munieri and the last occurrence of  d.  favrei . the upper psilotissotia colombiana subzone is characterized by p.  colombiana , holcodiscus , l.  anisoptychum and anahamulina paxillosa . according to data from the high atlas of morocco ( company et  al . , 2008 ) , two significant hiatuses appear at the hauterivian / barremian boundary and in the lower part of the k.  nicklesi zone . both were related to third - order sea - level falls by company et  al . ( 2008 ) , who pointed to similarities with the lowermost barremian ( t.  hugii zone to k.  compressissima zone ) intervals of the puez area . in both areas the t.  hugii zone in the high atlas is marked by the occurrence of emericicceras koechlini , a.  tabarelli , d.  favrei , barremites dimboviciorensis , l.  densifimbriatum , paraspiticeras sp . and hamulinites sp . no index ammonites were found . ( 2008 ) and vermeulen ( 2002 ) , d.  favrei extends only up to the lower part of the t.  hugii zone in spain , morocco and france . at puez the k.  nicklesi zone extends from the bottom of bed p1/95 up to the top of bed p1/104 . the overall situation and assemblage composition is a continuation of the underlying t.  hugii auct . zone in that it shows desmoceratidae with numerous specimens of barremites sp . and m.  cassidoides . hamulinidae occur with anahamulina sp . the phylloceratidae are characterized by the first appearance of p.  ponticuli and more specimens of p.  infundibulum . beds within the k.  nicklesi zone display numbers of species per bed from zero to three . six families occur within the zone with numbers per bed from zero to five , with highest values in the uppermost parts ( fig . the shannon index shows a mean value for the k.  nicklesi zone of 2.8 ( min . this indicates a strongly encreased species richness as seen in the k.  nicklesi zone but values are shifted because the ammonite occurrence is limited to a single bed ( fig . the base of the k.  nicklesi zone zone is defined by the first occurrence of k. nicklesi ( company et  al . , 2008 ) . this part is mostly devoid of ammonites and therefore not yet defined at the puez locality . more sampling is needed to confirm or refute any hiatuses . according to data from the western high atlas of morocco ( company et  al . , 2008 ) , the k.  nicklesi zone is only partly preserved there and encompasses only few beds . the index ammonite was detected and additional rare specimens of e.  koechlini , a.  tabarelli , paraspiticeras sp . , hamulinites sp . , lytoceras sp . and p.  ponticuli were detected , accompanied by new forms such as torcapella barremensis , subbpulchellia oehlerti , almohadites camelinus , holcodiscus thomeli and davidiceras cf . ( 2008 ) noted that only the upper part of the k.  nicklesi zone is represented in the western high atlas , following a hiatus in the lower part . species from the moroccan locality include forms that should be found at puez for clarification of zonal boundary . the n.  pulchella zone corresponds to the bottom of bed p1/105 up to the top of bed p1/111 ( fig .  2 , fig .  3 , fig .  6 ) . the ammonite assemblage is quite similar to that of the underlying k.  nicklesi zone . the family acrioceratidae occurs with the first specimens of dissimilites trinodosus ( fig .  3 , fig . beds within the n.  pulchella zone display numbers of species per bed from one to six . families occur within the zone with numbers per bed from zero to three , the highest numbers being in the uppermost parts ( fig . the shannon index shows a mean value for the n.  pulchella zone of 1.3 ( min . 0.9 , max . 1.6 ; this indicates a somewhat lowered species richness as seen in the uppermost barremian t.  hugii auct . the base of the n.  pulchella zone is defined by the first occurrence of n.  pulchella ( company et  al . , 2008 ) . in accordance with hoedemaeker ( 2003 ) the n.  pulchella horizon was elevated to the rank of a zone . the n.  pulchellia zone also replaces the upper part of the k.  nicklesi zone ( hoedemaeker and rawson , 2000 ) . comparable to the puez section , the n.  pulchella zone described by fzy and janssen , 2009 , fzy and janssen , 2006 from the gerecse mountains are typical , with k.  nicklesi ( determined as subpulchellia nicklesi in fzy and janssen , 2009 , fzy and janssen , 2006 ) and n.  pulchella . the assemblage is dominated by the first species , but numerous silesites sp . , frequent holcodiscus ssp . and the first ocurrences of the genus barremites were reported . the correlatable interval largely lacks ammonites and is not , therefore , yet defined at the puez locality . the last specimens of e.  thiollierei occur together with a.  subcincta and silesites vulpes in the lower parts of the n.  pulchella zone at angles ( southeast france ; vermeulen , 2002 ) . the n.  pulchella zone is dominated in the western high atlas of morocco by the index ammonite n.  pulchella accompanied by members such as a.  tabarelli , paraspiticeras sp . , hamulinites sp . , lytoceras sp . and p.  ponticuli along with forms such as d. cf . potieri , the first specimens of m.  nodosum and still frequent t.  barremensis , which is replaced towards the top by t.  suessi ( company et  al . , the k.  compressissima zone extends from the bottom of bed p1/112 up to the top of bed p1/118 . the ammonite assemblage is quite similar to the underlying n.  pulchella zone but more numerous in species and specimens . , m.  cassidoides and mechiorites sp . and the first specimens of valdedorsella cf . 6s ) and are accompanied by the first members of ptychoceratidae with ptychoceras sp . ( fig . 6h ) is the first member of macroscaphitidae to occur in the uppermost part of the zone . the topmost part of the k.  compressissima zone is marked by typical phylloceratidae with p.  tethys , phylloceras paquieri and phylloceras sp . , the first specimens of e.  phestum and numerous specimens of protetragonites crebrisulcatum ( fig .  6s ) and protetragonites sp . beds within the k.  compressissima zone display numbers of species per bed from three to seven . nine families occur within the zone with numbers per bed from zero to eight , the highest values being in the upper half ( fig . the shannon index shows a mean value for the k.  compressissima zone of 1.6 ( min . 0.7 , max . 2.3 ; the values indicate a lowering of species richness and a low evenness in their abundance compared to those of the n.  pulchella zone ( fig . the k.  compressissima and moutoniceras moutonianum zones were established after a proposal by company et  al . ( 1995 ) and replaced the top part of the k.  nicklesi zone and the holcodiscus caillaudianus zone ( hoedemaeker and rawson , 2000 ) . ( 2009 ) this zone is divided into the holcodiscus fallax , nicklesia didayana , heinzia communis and subtorcapella defayae horizons ( company et  al . , 1995 , company et  al . , 2008 , vermeulen , 2003 , vermeulen , 2007a , vermeulen , 2007b , vermeulen and klein , 2006 ) . as noted by fzy and janssen , 2009 , fzy and janssen , 2006 this zone can be easily recognised in the gerecse mountains by the index ammonite k.  compressissima ( determined as subpulchellia compressissima by fzy and janssen , 2009 , fzy and janssen , 2006 ) . numerous holcodiscids occur throughout the zone , including holcodiscus gastaldianus , h.  nicklesi , h. cf . the latter species seems to be restricted to the lower parts and h.  caillaudianus to the upper part of the zone ( company et  al . , 1995 , fzy and janssen , 2009 , fzy and janssen , 2006 ) . ( 2009 ) , where an h.  fallax horizon is noted in the lowermost part of the k.  compressissima zone . after fzy and janssen , 2009 , fzy and janssen , 2006 , moutoniceras appears within that zone , whereby moutoniceras nodosum is first representative . similar to the k.  compressissima zone from puez , the assemblage from bersek quarry shows additional representatives such as barremites sp . , mechiorites sp . and the first specimens within leptoceratoididae with karsteniceras pumilum ( fig . delanoy and joly ( 1995 ) and joly ( 2000 ) reported p.  ponticuli ( as a typical member of upper barremian ammonite assemblages but rare in lower barremian ) at puez with the first appearance of p.  ponticuli in the k.  compressissima subzone . ( 1992 ) described barremian faunas from the subbetic domain in the betic cordillera , characterizing the subpulchellia compressissima zone (=  k.  compressissima ) by the index ammonite k.  compressissima , subpulchellia nicklesi (=  k.  nicklesi of the recent k.  nicklesi zone ; reboulet et  al . , 2009 ) , n.  pulchella ( index for the recent n.  pulchella zone ; reboulet et  al . , 2009 ) , subpulchellia brevicostata ( k.  brevicostata ) , h.  perezianus and h.  caillaudianus . at angles ( southeast france ) , first k.  changarnieri occur in the stratotype in the uppermost k.  compressissima zone in the lower s.  defayae horizon (=  s.  defayae subzone after vermeulen , 2002 ) . macroscaphites , costidiscus and e.  phestum seem to originate in the k.  compressissima zone at the puez locality . the k.  compressissima zone is characterized in the western high atlas of morocco by a faunal turnover . this begins in the top of the underlying n.  pulchella zone , marked by the new index form k.  compressissima and other pulchelliids k.  didayana , heinzia communis and , in upper parts , k.  changarnieri . at the base of the zone , holcodiscids show a characteristic diversification ( company et  al . , 2006 , 2008 ) with h.  fallax , h.  perezianus , avramidiscus gastaldianus and , higher in the zone , h.  caillaudianus . ancyloceratoidea are present with m.  nodosum , dissimilites dissimilis and members of  toxoceras  and hamulinites . the occurrence of the index ammonite m.  moutonianum ( bed p1/119 ) with the co - occurring ammonite assemblage hints at the presence of the m.  moutonianum zone at the puez section ( fig .  2 , fig .  3 , fig .  6 ) . the m.  moutonianum zone corresponds to the interval from the bottom of bed p1/119 up to the top of bed p1/137 . the family desmoceratidae is represented by barremites sp . and m.  cassidoides . among the silesitidae , real s.  vulpes ( fig . heteroceratidae are present at the base of the zone for the first time with the zonal index ammonite m.  moutonianum ( fig . phylloceratidae are represented by the last individuals of p.  tethys , phylloceras sp . ; moreover , p.  infundibulum ( fig .  6 t , v ) , phyllopachyceras ladinum and phyllopachyceras sp . also occur . beds within the m.  moutonianum zone display numbers of species per bed from one to seven . seven families occur within the zone with numbers per bed from zero to five , the highest values being in the lowermost beds ( fig . the shannon index shows a mean value for the m.  moutonianum zone of 0.7 ( min . values indicate very low species richness and low evenness of abundance compared to other zones ( fig . the m.  moutonianum zone is defined by the first appearance of its index species and the co - occurrence in upper parts of toxancyloceras vandenheckii ( company et  al . , 1995 ) . the former coronites darsi zone sensu vermeulen , 1997 , vermeulen , 1998 ) and the c.  darsi zone sensu company et  al . the heinzia sayni zone of vermeulen , 1997 , vermeulen , 1998 is equivalent to the t.  vandenheckii zone . according to the data of vermeulen , 2005a , vermeulen , 2005b , the first occurrence of m.  moutonianum coincides with that of c.  darsi ( company et  al . , 2008 ) . ( 2009 ) assumed that the m.  moutonianum ( sensu company et  al . , 1995 ) and c.  darsi ( sensu vermeulen , 1997 , vermeulen , 1998 ) zones span the same stratigraphic interval . the m.  moutonianum zone (=  coronites darsi zone in company et  al . , 2008 ) is subdivided into a c.  darsi horizon and a younger h.  caicedi horizon ( reboulet et  al . , 2009 ) . within the gerecse mountains , fzy and janssen , 2009 , fzy and janssen , 2006 noted the presence of the index species m.  moutonianum and the genus heinzia with heinzia sp . and heinzia cf . these authors reported the index ammonite co - occurring with abundant k.  changarnieri and k.  sauvageaui (=  subpulchellia changarnieri and subpulchellia sauvageaui by fzy and janssen , 2009 , fzy and janssen , 2006 ) . numerous specimens of the genus heinzia occur , and h.  caicedi , when abundant , is typical for that zone . ( 2009 ) encompasses the upper half of the m.  moutonianum zone : h.  caicedi occurs a few beds lower in the k.  compressissima zone at puez . the family desmoceratidae shows mass occurrences of barremites and melchiorites in single beds ( fzy and janssen , 2009 , fzy and janssen , 2006 ) . are present together with ptychoceras puzosianum within that zone ( fzy and janssen , 2009 , fzy and janssen , 2006 ) . ptychocera puzosianum occurs somewhat later during the toxancyloceras vandenheckii zone in the subbetic region ( southeast spain ; company et  al . , in contrast , it was found only much higher at puez in the g.  sartousiana zone . the acrioceratidae in spain occur once again with dissimilites trinodosum , and hamulinidae occur with several species of anahamulina sp . avram , 1994 , avram , 2001 defined the ranges of d.  dissimilis , d.  trinodosum and d.  subalternatus within the romanian carpathians . he assumed that d.  dissimilis was present only in the uppermost lower barremian , whereas d.  trinodosum and d.  subalternatus were characteristic for both the uppermost lower barremian and lowermost upper barremian . ( 2000 ) for a range of d.  trinodosum starting in the k.  compressissima zone and reaching up to the m.  moutonianum zone . according to vermeulen ( 2007a ) , species of the genus costidiscus appear from the t.  vandenheckii zone and derive from ancestors in the base of the m.  moutonianum zone (=  c.  darsi zone of vermeulen , 2007a ) . as noted above , at puez costidiscus nodosostriatum occurs at the uppermost part of the k.  compressissima zone or k.  compressissima / m . vermeulen ( 2007a ) rejected the idea of costidiscus  macroscaphites being a sexually dimorphic pair owing to their different stratigraphical range , with costidiscus appearing in the t.  vandenheckii zone and macroscaphites in the k.  compressissima zone in southern france . the same situation is shown herein and strengthens vermeulen s assumption , which contrasts with the remarks made by avram , 1984 , delanoy et  al . , 1995 , wright et  al . , 1996 and delanoy et  al . fzy and janssen , 2009 , fzy and janssen , 2006 reported that both macroscaphites and costidiscus were present in the m.  moutonianum zone in the gerecse mountains of hungary . uhlig ( 1883 ) and vaek and wiedmann ( 1994 ) noted the typical occurrence of karsteniceras pumilium in the lower barremian of the silesian unit ( czech republic ) , which is in accordance to the specimens found at puez . avram ( 1994 ) reported a faunal condensation in the lowermost barremian of the south carpathian region around svinia . nevertheless , the overall assemblages are almost identical to the puez faunas in that they comprise , from the beginning , d.  favrei , barremites ssp . the first representatives of macroscaphites and costidiscus occur together with e.  phestum in the lowermost upper barremian of the svinia region , i.e. , t.  vandenheckii zone . macroscaphites , costidiscus and e.  phestum seem to arise earlier in the k.  compressissima zone at the puez locality . the m.  moutonianum zone of the subbetic domain in the betic cordillera was described by aguado et  al . specimens and subpulchellia (=  kotetishvilia ) and holcodiscus . in vermeulen s ( 2002 ) report on pulchelliids from the stratotype of angles ( southeast france ) , the coronites darsi zone (=  m.  moutonianum zone in reboulet et  al . , 2009 ) contains k.  changarnieri ( throughout ) and k.  sauvageaui ( upper part ) . the base of the upper barremian is , according to vermeulen ( 2002 ) , marked by the h.  uhligi zone (=  lower part of the t.  vandenheckii zone  after reboulet et  al . , 2009 ) , which is characterized by the co - occurrence of h.  uhligi , k.  changarnieri , k.  sauvageaui , t.  vandenheckii and rare specimens of moutoniceras and dissimilites . the h.  uhligi zone after vermeulen ( 2002 ) is followed by vermeulen s h.  sayni zone (=  upper part of the t.  vandenheckii zone after reboulet et  al . , 2009 ) , typical in showing h.  sayni , dissimilites sp . binodosus , ancyloceras vandenheckii (=  t.  vandenheckii ) and s.  seranonis . the g.  sartousiana zone , and especially the comparable g.  sartousiana subzone , is characterized by the index ammonite and the co - occurrence of camereiceras cf . limentinus , s.  seranonis and ezeiceras janus (=  janusites janus ) . the coronites darsi zone (=  m.  moutonianum zone in reboulet et  al . , 2009 ) is marked in the western high atlas of morocco by the rare occurrence of c.  darsi and more abundant m.  moutonuianum . additionally , d.  dissimilis , barremites vocontius and  melchiorites  rumanus are frequent and appear with c.  darsi , k.  changarnieri , t.  suessi , holcodiscus diversecostatus , h.  perezianus and s.  vulpes . the t.  vandenheckii zone extends from the bottom of bed p1/138 up to the top bed p1/193 ( fig .  2 , fig .  3 , fig .  7 , the appearance of the index ammonite t.  vandenheckii in bed p1/138 marks the lower boundary of the t.  vandenheckii zone ( fig .  2 , fig .  3 , fig . the t.  vandenheckii zone is subdivided into the t.  vandenheckii subzone and the younger b.  barremense subzone . owing to the absence of the subzonal index ammonites , the t.  vandenheckii zone is tentatively subdivided into two equal parts at bed p1/172 , which corresponds with the last occurrence of heinzia cf . the zone occurs with a typical ammonite fauna comprising members of the family desmoceratidae , with barremites sp . , valdedorsella sp . occur within the holcodiscidae only in the lower part of the t.  vandenheckii zone . 8x ) in the lower part and additional specimens of k.  sauvageaui in both parts . are frequent in the lower part and are accompanied by the zonal index species t.  vandenheckii ( fig . 8 m ) and duyeina sp . , whereas the upper part is characterized by the occurrence of the hamulinid member vasicekina cf . macroscaphitidae occur with only one specimen at the base , along with costidiscus sp . typical members within the phylloceratidae occur throughout the zone and include p.  ponticuli , phylloceras sp . , p.  infundibulum , p.  eichwaldi , phyllopachyceras sp . and sowerbyceras ernesti . beds within the t.  vandenheckii zone display numbers of species per bed from one to nine . twelve families occur within the zone with numbers per bed from zero to eight , with highest numbers dispersed throughout the zone ( fig . if separated into the t vandenheckii subzone and b.  barremense subzone the former contains eleven families and the latter seven . the shannon index shows a mean value for the t.  vandenheckii zone of 1.1 ( min . values indicate slightly higher values of species richness and higher evenness of abundance compared to the m.  moutonianum zone ( fig . the t.  vandenheckii zone is marked by the first appearence datum of the index ammonite (=  lower / upper barremian boundary ; rawson et al . , 1999 ) and the co - occurrence g.  sartousiana in the upper parts ( company et  al . , 2008 , ( 2009 ) the t.  vandenheckii zone is subdivided into the t.  vandenheckii subzone and the younger barrancyloceras barremense subzone . the former h.  sayni subzone ( reboulet et  al . , 2006 ) was replaced by the lower t.  vandenheckii subzone ( reboulet et  al . , 2009 ) . after vermeulen ( 2005b ) , duyeina kleini is characteristic for the g.  sartousiana zone and gerhardtia provincialis zone , which were both incorporated into a single g.  sartousiana zone with a lower g.  sartousiana subzone , a middle g.  provincialis subzone and an upper hemihoplites feraudianus subzone . in southern france the genus duyeina itself appears throughout the upper barremian and has its ancestors in the t.  vandenheckii zone ( vermeulen , 2005b ) , which subsequently could be the case with the specimen herein ( i.e. , duyeina cf . the species k.  changarnieri and k.  sauvageaui are first  present at puez within the t. vandenheckii zone ( lower part  =  t.  vandenheckii subzone ) . the first specimens of k.  sauvageaui in southern france occur in the m.  moutonianum zone within the h.  caicedi horizon ( vermeulen , 1998 ) , whereas k.  changarnieri has its acme in southern france within the k.  compressissima zone and disappears in the heinzia sayni zone ( uppermost t.  vandehckii zone of reboulet et  al . , 2009 ) . the same range for k.  sauvageaui was reported from algeria by vermeulen and lahondre ( 2008 ) . at puez , h. cf . h.  syani occurs in the upper part of the t.  vandenheckii zone , which is comparable to the h.  sayni zone after vermeulen , 2007a , vermeulen , 2007b . it disappears in the tethyan region at the base of the b.  barremense subzone ( after vermeulen and lazarin , 2007 ) . vermeulen and lazarin ( 2007 ) subdivided the t.  vandenheckii zone into t.  vandenheckii , h.  sayni and b.  barremense subzones . ( 2009 ) into a t.  vandenheckii subzone and a younger b.  barremense subzone . the biozone is marked by  the  strong diversification of the ancyloceratoidae ( toxancyloceras ,  barrancyloceras ) and acrioceratidae ( dissimilites ) . ( 2008 ) is characterized by the co - occurrence of heinzia syani , kotethisvila sp . , gassendiceras sp . , barrancyloceras sp . and t.  vandenheckii . the t.  vandenheckii zone after bert et  al . ( 2008 ) included the lower holcodiscus uhligi , the middle h.  sayni and the upper b.  barremense subzones , and several additional biohorizons were introduced . the lower two subzones are time equivalent to the t.  vandeheckii subzone after reboulet et  al . according to fzy and janssen , 2009 , fzy and janssen , 2006 the t.  vandenheckii zone is the topmost preserved zone at the bersek quarry , shown by the presence of the index ammonite and h.  sayni . this agrees with the occurrence of h.  sayni at puez within the entire t.  vandenheckii zone . the authors reported the t.  vandenheckii zone by determining t.  vandenheckii , h.  sayni and an additional fauna comprising kotetishvilia sp . ( determined as subpulchellia in fzy and janssen , 2009 , fzy and janssen , 2006 ) , holcodiscus ssp . , dissmimites sp . both the puez area and the gerecse mountains show the occurrence of small leptoceratoididae with karsteniceras and hamulinidae with hamulina sp . , a. cf . vaek ( 1996 ) also reported t.  vandenheckii from the central western carpathians ( butkov , quarry , slovakia ) . from the silesian of the czech republic , vaek , 1999 , , 2004 reported a typical upper barremian assemblage including macroscaphites binodosus and m.  yvani , and c.  nodosostriatus within the t.  vandeheckii zone . sauvageaui , described as deriving from the upper barremian from the silesian unit ( western carpathians ) . patrulius and avram ( 2004 ) described but did not figure an assemblage comprising k.  changarnieri and pulchellia caicedi (=  h.  caicedi ) as typical for their m.  moutonianum zone . ( 1994 ) reported a comparable fauna from the t.  vandenheckii zone in the sierra del corque ( capres section cp2 ) from an intermittent zone between the subbetic and prebetic ranges ( southeast spain ) . the t.  vandenheckii assemblage at capres is characterized by the typical co - ocurrence of p.  infundibulum , m.  cassidoides , barremites spp . k.  sauvageaui and k.  cangarnieri ( subpulchellia sauvageaui and s.  changarnieri of company et  al . , 1994 ) , d.  trinodosum , and t.  vandenheckii (=  ancyloceras vandenheckii in company et  al . , 1994 ) . ( 1992 ) described barremian faunas from the subbetic domain in the betic cordillera with emericiceras barremense (=  b.  barremense ) , hemihoplites feraudi and heteroceras astieri zones for the upper barremian . the upper barremian e.  barremense (=  b.  barremense ) zone was reported with heinzia provincialis ( g.  provincialis , index for g.  provincialis subzone : reboulet et  al . , 2009 ) the h.  feraudi zone (=  uppermost h.  feraudianus subzone of the g.  sartousiana zone ; reboulet et  al . ( 2009 ) ) was characterized by the presence of macroscaphites yvani and m.  ectotuberculatus , costidiscus sp . , b.  strettostoma , s.  seranonis , pseudohaploceras and ptychoceras sp . additionally hemihoplites and the last subpulchellia (=  kotetishvilia ) occur . the h.  astieri zone was reported with a specimen of heteroceras sp . the t.  vandenheckii zone is not well represented in the western high atlas area in morocco ( company et  al . , 2008 ) ; it is marked only by the index ammonite and by several members at the base such as h.  sayni , the last m.  moutonianum , barremites sp . and in the upper parts , new forms such as b.  barremense sp . or k.  sauvageaui . the g.  sartousiana zone at the puez section extends from the bottom of bed p1/194 up to the end of log p1 with the top of bed p1/204 . the lower boundary is fixed by the first appearance of the  zonal index ammonite g.  sartousiana in bed p1/194 ( fig .  2 , fig .  3 , fig . 8 t ) . within the holcodiscidae , one last specimen of holcodiscus sp . was found . pulchelliidae appear with the typical genus - pairing of the zonal index species g.  sartousiana ( fig .  8w , y , z , za ) , gerhardtia sp . and k.  sauvageaui ( fig . macroscaphitidae appear with their most frequent members , namely m.  yvani ( fig . 8zf ) , p.  eichwaldi , p.  ladinum , phyllopachyceras sp . and s.  ernesti . 8zd ) , p.  crebrisulcatum and protetragonites sp . throughout the g.  sartousiana zone . beds within the g.  sartousiana zone display numbers of species per bed from one to fourteen . ten families occur within the zone with numbers per bed from one to nine , the highest numbers being in the middle part , but high throughout the zone ( fig . the shannon index shows a mean value for the g.  sartousiana zone of 1.6 ( min . values indicate ( not significant ) slightly higher values of species richness and higher evenness of abundance compared to the t.  vandenheckii zone ( fig . nevertheless , single beds within this zone have yielded abundances of ammonites with over 120 ( bed 197 ) or even more than 200 specimens per bed ( bed 199 ) . g.  sartousiana appears in the g.  sartousiana zone and disappears within the g.  provincialis subzone in algeria ( vermeulen and lahondre , 2008 ) and southern france ( vermeulen , 2002 ) . delanoy , 1994 , delanoy , 1997 described typical asemblages from the g.  sartousiana zone from the  coupe vergons 2  section ( southeast france ) . the fauna comprises similar assemblages with k.  sauvageaui ( delanoy s psilotissotia sauvageaui ) and members of genera such as macroscaphites , costidiscus and s.  vulpes , p.  ponticuli , p.  infundibulum and e.  phestum . delanoy ( 1997 ) described the same assemblage as typical for the g.  sartousiana zone in southeast france . they reported the anomalies in the first occurrence of different sections and therefore had difficulty marking the lower boundary of the g.  sartousiana zone . ( 2008 ) were not accepted and transferred to the ammonite zonation scheme for the mediterranean by the kilian group ( reboulet et  al . , 2009 ) . ( 2008 ) summarized the strong diversification in hemihoplitidae and the coeval decrease in pulchelliids after the acme of g.  sartosuiana . ( 2008 ) included the lower camereiceras limentinus , the middle gerhardtia provincialis and the upper hemihoplites ferraudianus subzones . equivalents are the g.  sartousiana , the g.  provincialis and the h.  ferraudianus subzones after reboulet et  al . ( 2008 ) is characterized by the co - occurrence of g.  sartousiana , g.  provincialis , c.  limentinus , hemihoplites ssp . and hemiholitidae with the genera hemihoplites , gassendiceras and pseudoshasticrioceras ( see bert and delanoy , 2009 , bert et  al . , 2008 ) are still missing at the top of the puez section ( log p1 ) , implying the absence of the time equivalent beds from the middle part of the g.  sartousiana zone , i.e. , the g.  sartousiana / provincialis boundary upwards . it is difficult to correlate with species determined by cecca and pallini ( 1994 ; see also vermeulen and klein , 2006 ) because no exact zonation is given and the boundaries are therefore uncertain , nonetheless , faunas seem to appear with same constituents as those of the late barremian time intervals detected at puez . ( 2009 ) divided the g.  sartousiana zone into the  g.  sartousiana subzone , the g.  provincialis subzone and the youngest h.  feraudianus subzone . ( 2008 ) the former zone of h.  feraudianus was lowered to the rank of a subzone and occupies the upper part of the g.  sartousiana zone ( reboulet et  al . , 2009 ) . concerning the arguments given by reboulet et  al . ( 2009 ) , the boundary between the g.  sartousiana and imerites giraudi zones is characterized by an important faunal turnover marked by the disappearance of pulchellidae and hemihoplitinae . based on the ammonite assemblage and further lithological and microfossil analysis , the upper two ammonite subzones , i.e. , the g.  provincialis and h.  feraudianus subzones , are probably missing and a hiatus occurs at this time at the top of log p1 after bed p1/204 . the hiatus in the mid g.  sartousiana zone is comparable to situations in southeast spain ( company et  al . , 1994 ) , where in the capres section the g.  sartousiana ( including h.  feraudianus subzone ) and imerites giraudi zones are condensed within only 2  m. the condensed lower part was determined by the index species of g.  sartousiana ( heinzia sartousiana in company et  al . , 1994 ) . the g.  sartousiana zone was reported only from the most distal localities in the western high atlas . ( 2008 ) reported a mixture of lower zone ammonites such as k.  brevicostata , janusites cf . janus and camereiceras sp . with ammonite forms characteristic for the upper part such as g.  provincialis , ( 2006 ) discussed the urgonian platform carbonates in the helvetic alps ( switzerland ) . they demonstrated that the time of the g.  sartousiana zone is coeval with the increasing productivity of the urgonian facies around the western tethyan realm . ( 2008 ) showed that , during the time represented by the b.  balearis zone , a change to a more humid climate occurred ; this predates the faraoni event and the demise of the carbonate platform of the helvetic zone , lasting from the late hauterivian spathicrioceras angulicostatus and p.  mortilleti zone ( zonation of godet et  al . , 2008 ;  =   p. 2009 ) until the late early barremian c.  darsi zone (=  m.  moutonianum zone in reboulet et  al . , 2009 ) . from g.  sartousiana zone times , the carbonate production on the platforms increased again , subsequently accompanied by a remarkable sea - level rise ( adatte et  al . , 2005 , arnaud , 2005 , godet et  al . , lithological differences observed around the puez are clearly consequences of an altered palaeo - oceanography and therefore reflect sea - level fluctuations during the early cretaceous , especially within the early late barremian ( i.e. , the g.  sartousiana zone ) . a major rise in sea level took place during the time represented by the g.  sartousiana zone ( adatte et  al . , 2005 , arnaud , 2005 ) of the uppermost puez limestone member ( lower puez formation ; puez / log 1 ) , containing the melchiorites - level ( beds p1/194 - 204 ) , which is dominated by the genera melchiorites and silesites ( fig .  2 , fig .  5 , fig .  7 ) . ( 2005 ) interpreted barremites , comparable to the morphotype melchiorites , as being epipelagic nekton and silesites was described as nektobenthic . migrations  have always been considered as being controlled by transgressive and regressive cycles in various lower cretaceous ammonite groups ( rawson , 1981 , hoedemaeker , 1990 ) . this phenomenon was described by bulot ( 1993 ) as opportunity hufs ( horizons of faunal uniformity ) . opportunity hufs were determined to be locally controlled by changing conditions marked by the change in palaeogeographic distribution or of palaeoecological ranges of different ammonite groups . the remarkable assemblage change within the melchiorites - level ( g.  sartousiana zone ) reflects a complex of changes in eustasy and in primary bioproductivity ( lukeneder , 2003 , lukeneder , 2004b ) . the macrofauna of the puez formation at the puez section , especially of the puez limestone member , is mainly represented by ammonites . over 1200 ammonite specimens were collected by bed - by - bed sampling . aptian and albian members such as the puez redbed member and the puez marl member are almost barren in ammonites and other macrofossils . the ammonite zonation is based on the most recent standard zonation of the international kilian group on lower cretaceous ammonites ( reboulet et  al . , 2009 ) . several zones and even subzones based on the presence of mediterranean index ammonites , such as the c.  krenkeli , p.  mortilleti , p.  picteti , m.  moutonianum , t.  vandenheckii and g.  sartousiana ammonite zones , were detected . the fossiliferous parts of the log begin with the upper hauterivian b.  balearis zone ( b.  binelli subzone ) . the ammonite - rich section ends with a significant hiatus within the lower upper barremian g.  sartousiana zone ( g.  sartousiana subzone ) . this hiatus is marked at the top of bed 204 by an omission horizon , and is directly overlain by the aptian puez redbed member . the situation is comparable to that of other localities located in southeast spain and morrocco . lower aptian hiatus extends from the middle part of the g.  sartousiana zone up to the base of the aptian , reflecting the absence of at least the topmost part of the g.  sartousiana subzone ( i.e. , h.  feraudianus subzone ) and the entire i.  giraudi zone . the ammonite assemblage clearly indicates a mediterranean character , as reported from numerous comparable lower cretaceous localities in east - central european ( czech republic , france , hungary , slovakia , spain ) , eastern europe ( bulgaria , romania ) and african localities ( algeria , morocco ) . the fauna is dominated by phylloceratids ( p.  infundibulum , p.  tethys ) , lytoceratids ( lytoceras , eulytoceras , protetragonites ) , desmoceratids ( barremites , melchiorites , silesites ) and anycloceratids ( anahamulina , crioceratites , dissimilites , karsteniceras , pseudothurmannia , toxancyloceras ) . ammonite - rich beds were detected within the c.  krenkeli zone , the t. vandenheckii zone and the topmost g.  sartousiana zone . abundance peaks occur in bed 66 ( n  >  60 ) in the c.  krenkeli zone and in the g.  sartousiana zone in beds 197 ( n  >  120 ) and 199 ( n  >  200 ) . the evaluation of biodiversity calculated by the ratio between number of species vs. number of individuals per species ( shannon index ) shows no clear significance throughout the puez section , although varying from highstand and maximum flooding phases from the upper hauterivian with mean  values of 1.6 down to ( in steps ) values of 0.7 in the lower barremian m.  moutonianum zone . ammonite abundances are clearly linked to sea - level changes from late hauterivian to mid late barremian times . abundance and diversity peaks occur during phases of high sea - level pulses and the corresponding maximum flooding surfaces ( p. the uppermost hauterivian to lowermost barremian interval has often be reported to be difficult for biostratigraphy because of a potential condensation or a manifestation of a hiatus ( patrulius and avram , 2004 , company et  al . , 1994 ) . the ammonite data are the first step in a detailed biostratigraphic scheme for the puez key - section . more investigations at the stratotype of the puez formation will be carried out within the dolomite project p20018-n10 ( project of the austrian science fund fwf ) . additional ammonite collections will be carried out in future to determine the exact position of stage- , zone- , and subzone - boundaries . analyses will include palaeomagnetic , isotope and geochemical analyses along with a detailed biostratigraphy based on micro- and nannofossils .
a biostratigraphic subdivision , based on ammonites , is proposed for the lower cretaceous pelagic to hemipelagic succession of the puez area ( southern alps , italy ) . 
 abundant ammonites enable recognition of recently established mediterranean ammonite zones from the upper hauterivian balearites balearis zone ( crioceratites krenkeli subzone ) to the upper barremian gerhardtia sartousiana zone ( gerhardtia sartousiana subzone ) . 
 ammonites are restricted to the lowermost part of the puez formation , the puez limestone member ( ca . 50  m ; marly limestones ; hauterivian 
 barremian ) . 
 numerous ammonite specimens are documented for the first time from the southern alps ( e.g. , dolomites ) . 
 ammonite abundances are clearly linked to sea - level changes from late hauterivian to mid late barremian times . 
 abundance and diversity peaks occur during phases of high sea - level pulses and the corresponding maximum flooding surfaces ( p. 
 mortilleti / p . 
 picteti and g.  sartousiana zones ) . 
 the ammonite composition of the puez formation sheds light on the early cretaceous palaeobiogeography of the dolomites . 
 it also highlights the palaeoenvironmental evolution of basins and plateaus and provides insights into the faunal composition and distribution within the investigated interval . 
 the intermittent palaeogeographic situation of the puez locality during the early cretaceous serves as a key for understanding mediterranean ammonite distribution .