Updated ammonite biostratigraphy from

1661-5468

VOL. SPéC - N° 11, 2012

ISSN 0253-6730

1 Departamento de Paleontología, Instituto de Geología, UNAM, Ciudad Universitaria, 04510 México D.F., Mexico. E-mail: [email protected]

2 Departamento de Estratigrafía y Paleontología, Facultad de Ciencias, Universidad de Granada, Av. Fuentenueva s/n, 18002 Granada, Spain. E-mail: [email protected]

3 Servicio Geológico Mexicano, Boulevard Felipe Ángeles Km 93.50-4, Col. Venta Prieta, 42080 Pachuca, Hidalgo, Mexico. E-mail: [email protected]

4 Posgrado en Ciencias de la Tierra, Sede Instituto de Geología, UNAM, Ciudad Universitaria, 04510 México D.F., Mexico. E-mail: [email protected]

I. INTRODUCTION

Apart from taphonomy, effective, experimental biostratigraphic ranges are largely determined by palaeoenvironmental conditions forcing favourable habitats for local populations. A context of at most not very deep, neritic environments with irregular, unstable bottom physiography accentuating the influence on relative sea level fluctuations, has been proposed to determine environmental patchiness for

ammonites, r-strategy, and variable endemism during the Late Jurassic in Mexican areas (Olóriz, 1987, 1992; Olóriz et al., 1990a). Hence, fragmentary records and limitations to precise reproducibility and homotaxy of both ammonite data and then correlations pose serious difficulties for interpreting precise biostratigraphy and entail the need for careful sampling bed-by-bed (Olóriz, 1992; CallOmOn, 1992; VillaseñOr et al., 1994; and references herein). The first published, valuable approach identifying essentially discontinuous

Revue de Paléobiologie, Genève (2012) Vol. spéc. 11: 249-267

Updated ammonite biostratigraphy fromUpper Jurassic deposits in Mexico

Ana Bertha VillaseñOr1, Federico Olóriz2 , Isabel López PalOminO3 & Iriliana López-CaballerO4

AbstractTen years after the publication of “Recent advances in Upper Jurassic (Kimmeridgian-Tithonian) ammonite biostratigraphy of north-central Mexico, based on recently collected ammonite assemblages”, a working program based on bed-by-bed sampling of upper Jurassic sections in Mexico has allowed to improve information about known and new outcrops in northeastern, central-eastern and south-eastern Mexico. The present contribution provides an updating of the obtained information, a part of which has been published elsewhere. Of special relevance are new data concerning Oxfordian and latest Kimmeridgian/earliest Tithonian ammonites from central-east and south-eastern Mexico, which are considered as preliminar information of prime importance for correlation. A re-evaluation of registered ammonite assemblages is made in terms of faunal – ammonite – horizons of three orders of relevance for biostratigraphic correlation in Mexico. They integrate within the ammonite assemblages formally proposed previously, and their biochronostratigraphic meaning is only tentatively approached due to the incidence of endemism.

KeywordsBiochronostratigraphy, Ammonites, Oxfordian, Kimmeridgian, Tithonian, Mexico.

ResumenActualización de la bioestratigrafia de ammonites del Jurásico Superior de México.- Después de 10 años de la publicación del trabajo donde se aportaron datos que implementaron el conocimiento e interpretación bioestratigráfica y las correlaciones biocronoestratigráficas del Jurásico Superior (Kimmeridgiano-Tithoniano) en México, se presenta una actualización bioestratigráfica basada en información generada desde entonces. La información considerada se encuentra en parte ya publicada y en parte es inédita, emanada de la investigación en curso en secciones del noreste, centro-este y sur de México. Se destacan los registros de ammonites oxfordianos y del tránsito Kimmeridgiano-Tithoniano, que modifican y amplían las posibilidades de correlación. Las asociaciones registradas son reevaluadas en términos de horizontes faunísticos, de ammonites, jerarquizados en tres órdenes de relevancia para la correlación bioestratigráfica en México. Dichos horizontes faunísticos se integran en las asociaciones que habían sido formalmente propuestas previamente y su significación biocronoestratigráfica es interpretada de manera preliminar debido a la incidencia de endemismo.

Palabras claveBiocronoestratigrafia, Ammonites, Oxfordiano, Kimmeridgiano, Tithoniano, México.

250 A. B. VillaseñOr, F. Olóriz , I. López PalOminO & I. López-CaballerO

faunal horizons in the Upper Jurassic of Mexico (CallOmOn, 1992) was based on bibliography and therefore affected by experimental uncertainties induced by old-fashion biostratigraphy –i.e., based on ammonite records retrieved from rather homogeneous sedimentary packages without reference to the precise stratigraphic location of ammonite specimens.Since the publication by VillaseñOr et al. (2000a), which showed the progress in Kimmeridgian-Tithonian ammonite biostratigraphy and biochronostratigraphic correlation based on a research program conducted on bed-by-bed sampling of classic and new sections from the Upper Jurassic in Mexico, new information from different Mexican areas has been published (Olóriz et al., 2000, 2003, 2008, 2010; VillaseñOr et al., 2003, 2004, 2005, 2011; Olóriz & VillaseñOr, 2006; lópez-palOminO et al., 2006; Cantú-Chapa, 2003, 2006, 2009a, b; VillaseñOr & Olóriz 2009, 2010). This information and new data gathered from Oxfordian-Tithonian sections, sampled bed-by-bed, allow us to accomplish more accurate biostratigraphic

and biochronostratigraphic interpretations. The present contribution updates existing information through approaching a synthesis of this information.The new data were obtained by the authors in eight new sections investigated in north-eastern, central-east and southern Mexico, in the States of Coahuila, Zacatecas, San Luis Potosí, Hidalgo, Puebla and Veracruz (Fig. 1).

II. OXFORDIAN

Ammonites from lateral equivalents of the top of the Zuloaga or La Gloria Formations were interpreted as Upper Oxfordian, mainly Bimammatum Zone (Olóriz et al., 1990b, 2008; myCzynski et al., 1998; Cantú-Chapa, 2001). Later research on the lower part of the type section of the Santiago Formation in the southeast of the San Luis Potosí State (VillaseñOr et al., 2002, 2004; lópez-palOminO et al., 2006; Olóriz et al., 2008), in Cucurpe, Sonora (VillaseñOr et al., 2005) and in one section cropping out near Las Choapas region in Veracruz

Fig. 1: Location of the studied areas. Continuous sections sampled bed-by-bed for a given area are indicated by numbers [no subsections included].

Updated ammonite biostratigraphy from Upper Jurassic deposits in Mexico 251

State (Olóriz et al., 2010), allows complementary information through recognition of several significant ammonite records of Middle Oxfordian age.The most important assemblage for ammonite biostrati-graphy and biochronostratigraphic correlation is the Gregoryceras assemblage characterized by the identified range of the widespread genus Gregoryceras, which was first recorded in Mexico by lópez-palOminO (2002, see also VillaseñOr et al., 2002, 2004). These authors interpreted the record of inner whorls of Gregoryceras sp. as Middle Oxfordian in age (corresponding to the Plicatilis Zone, Antecedens subzone). An interesting and diversified record of Oxfordian ammonites were re-corded from the base of a section near Las Choapas area, where relatively common ammonite fragments belong to the genus Gregoryceras, interpreted as Gregoryceras sp. of the G. riazi group (Olóriz et al., 2010, see Pl. I, fig. 1) of Middle Oxfordian age (Plicatilis to Transversarium chrones, at least pro parte). Mirosphinctes sp. group of M. frickensis (mOesCh), Neocampylites delmon-tanus (Oppel), Ochetoceras (Cubaochetoceras) sp. gr. mexicanum (burCkhardt)-burckhardti (O’COnnell) (Pl. I, figs. 2-5), Ochetoceras sp., Lissoceratoides sp., Glochiceras sp., and perisphinctids morphologically related to genera Antilloceras?, Cubasphinctes and “Subdiscosphinctes” (under study) were also recorded in this assemblage. From subsurface wells of the Campeche Shelf, Gulf of Mexico area, Cantú-Chapa (2001, 2009a) reported ammonites assigned to Ochetoceras and Discosphinctes, which were first interpreted as Late Oxfordian in age (Cantú-Chapa, 2001), and later as late Middle Oxfordian (Cantú-Chapa, 2009a). This author mentioned that Ochetoceras and Glochiceras “represent necessary biostratigraphic elements for picking the base of the Middle Oxfordian in the Campeche wells studied” (Cantú-Chapa, 2009a, p. 85), but no details were given supporting his assertion. As generally accepted, the taxonomy and biostratigraphic interpretation of ochetoceratins is not yet conclusively understood in the area, and isolate records of fragmented specimens (see Cantú-Chapa, 2009a, fig. 5) should be taken with caution. From all the above mentioned, only the record of the genus Gregoryceras (Fig. 2) from the Oxfordian in Mexico supports biostratigraphic precision and allows correlations around the world.In central-east Mexico, ammonite assemblages have been recognized above the Gregoryceras assemblage (VillaseñOr et al., 2004; Olóriz et al., 2008), and part of this information is under study (PhD thesis in preparation by I. lópez-palOminO). The recognized limitations for precise biostratigraphic correlations derived from endemism are worth mentioning here, as exemplified by the genus Vinalesphinctes (lópez-palOminO et al., 2006), of which two new species were identified – V. tamanensis lópez-palOminO et al. and V. tenangensis lópez-palOminO et al. This new Vinalesphinctes record

was interpreted as Late Oxfordian in age (corresponding to a part of the Bifurcatus Zone), and lópez-palOminO et al. (2006) widely discussed the interpreted age of Mexican, Cuban and Chilean Vinalesphinctes faunas, but no basis for intra-biochronozone discrimination was available. Other examples of endemism can be found in new forms preliminarily labelled as “Subdiscosphinctes” sp. of the “S.” carribeanus (JawOrski) group (Pl. I, figs. 7, 8), in association with Euaspidoceras oconnellae (sánChez-rOig) (Pl. I, fig. 6), which are interpreted here as Late Oxfordian (probably late Bifurcatus Chron) being yet another example of the difficulties for obtaining a greater precision about the relative position of faunal horizons within this biochronozone (Fig. 2).More information about Oxfordian ammonite assem-blages is needed from the Mexico-Caribbean area, and precise stratigraphic control is a prerequisite for future interpretations. For the time being, taxonomic interpreta-tions, even reasonable ones, cannot be conclusive for the Oxfordian in the Americas. Comparatively discontinuous stratigraphical and palaeogeographical ranges of ammo-nite occurrences determine the incomplete character of their successions, making it very difficult to recognize homotaxial records.

III. KIMMERIDGIAN

Few new data have been obtained after the biostratigraphic updating proposed by VillaseñOr et al. (2000a) for Kimmeridgian ammonite assemblages. New records of the Schneidia assemblage were gathered from a new outcrop near Saltillo, Coahuila State in north-eastern Mexico (lópez-CaballerO, 2009) and from one section in the Tamán area, San Luis Potosí State in central-east Mexico (Jiménez-lópez, 2011). From these areas Schneidia-like ataxioceratins were reported from the lower parts of the La Casita/La Caja Formation and the Tamán Formation, respectively. From the latter, Schneidia sp. group of S. lussasense atrOps was also preliminary reported, but revision indicates the record of an incomplete, macroconch specimen most probably belonging to Ataxioceras group of the hypselocyclum FOntannes - discoidale sChneid morphological plexus (Pl. I, fig. 9), together with Taramelliceras (Metahaploceras) sp. aff. subnereus (wegele). Nevertheless, these data are scattered, isolate records stratigraphically disconnected from the overlying Kimmeridgian rocks with Idoceras, or they overly Oxfordian deposits without precise age-interpretation due to ammonite-poor deposits. These records of ataxioceratin ammonites extend the possibilities of correlation between north-eastern and central-east regions in Mexico (Fig. 3), and their contribution to wide-regional correlation is envisaged for the near future.The next, younger, two Kimmeridgian ammonite assemblages proposed by VillaseñOr et al. (2000a),


Fig. 2: Correlation chart for the Oxfordian [parts 1 and 2]. Biostratigraphic proposals in chronological order from left to right. Part 1 shows selected proposals for ammonite biostratigraphy in Mexico, made before 1990. Narrow grey boxes showing

original stage/substage level bio-chronostratigraphic interpretations in the corresponding author(s) columns.

Part 1


Part 2 shows proposals from 1990 onwards, mainly including new ammonite data collected by the authors from southeastern Mexico after 2000. Ammonite assemblages in grey for biostratigraphic interpretations without precise reference at the biozone level. Broken lines indicate no precise biostratigraphic range for the ammonite assemblages involved. European standards on the left slightly adapted from CariOu & hantzpergue (1997) with absolute age datum according to przybylski et al. (2010). On the right column of part 2, short broken lines indicate correlation with European Standard Zone boundaries. Ammonite horizons: Broken-line boxes for those used for regional correlation, and continuous-line boxes for within-Mexico inter-regional correlation. Italics for taxa retrieved as local, single-section records (see part 2 for complementary information).

Part 2


were characterized by the record of Idoceras in north-central Mexico. This stratigraphic interval was subdivided on the basis of the record of Sutneria; the lower assemblage without occurrence of Sutneria, and the upper one including Sutneria group of S. cyclodorsata (mOesCh). In addition, in surface and subsurface reports from central-east Mexico, a region which includes the Tamán area, Cantú-Chapa (1969, 1971, 1979, 1984) recognized an Idoceras assemblage containing Aspidoceras and/or Nebrodites, but no data about precise stratigraphy were given. On this basis, the assemblage reported by Cantú-Chapa (op. cit.) is difficult to fit biostratigraphically in the context of the data presented by VillaseñOr et al. (2000a), based on sections sampled bed-by-bed, and cannot be conclusively interpreted as representing a single, cohesive vs. an empirically averaged ammonite assemblage.In the Tamán region we have recently collected scarce and moderately well-preserved ammonites, under precise stratigraphic control and above the record of ataxioceratins preliminary interpreted as belonging to Schneidia (see above). Evidence for the occurrence of an Idoceras assemblage was indicated, together with rare small specimens of Physodoceras, Aspidoceras, perisphinctids and incomplete Glochiceras. Poor preservation hinders precise taxonomic interpretation, but specimens assigned to Idoceras and the absence of Sutneria of the S. cyclodorsata (mOesCh) group, Nebrodites and Mesosimoceras, clearly support the interpretation of the assemblage as corresponding to the Lower Idoceras assemblage without Sutneria as proposed by VillaseñOr et al. (2000a) (Fig. 3). Hence, the biostratigraphic subdivision of the “Unidad con Idoceras” (= “Biozona de Idoceras”) recognized by Cantú-Chapa (1969, 1971) in the Huasteca area seems available, as well as a more precise biostratigraphic interpretation of the assemblage reported by this author.Biostratigraphic improvement also applies to the next “Upper Idoceras assemblage with Sutneria” reported by VillaseñOr et al. (2000a). The new records were gathered from two close areas, Amatitla (Olóriz & VillaseñOr, 2006) and Las Campanas (Hidalgo State, lópez-gómez, 2006), both in the Huasteca region. Of particular interest is the record of Ceratosphinctes rachistropus amatitlaensis Olóriz & VillaseñOr (see Olóriz & VillaseñOr, 2006, p. 7-8 for the associated macrofauna), and the recorded ammonite assemblage characterized by fragmented Idoceras of the I. durangense burCkhardt and I. balderum burCkhardt non Oppel groups, together with Sutneria of the cyclodorsata (mOesCh) group, as well as Nebrodites and Mesosimoceras reported by lópez-gómez (2006). These ammonite records support the biostratigraphic interpretation and correlation with the “Upper Idoceras assemblage with Sutneria” proposed by VillaseñOr et al. (2000a), improving possibilities of wider regional correlation for Kimmeridgian deposits in

Mexico as well as with other Tethyan regions (Fig. 3). Interesting for correlation are the records of Idoceras in Las Choapas region from south-eastern Mexico (research in preparation by F. Olóriz and a.b. VillaseñOr).No new data about the Subneumayria-Epicephalites ammonite horizon and the Taramelliceras - Aulacostephanus ammonite horizon reported in VillaseñOr et al. (2000a) were obtained. According to existing information, these horizons seem to be valid only for north-eastern Mexico.The next Kimmeridgian ammonite assemblage presently known from a Mexican area other than north-eastern Mexico is the Coryceras assemblage, with and without Procraspedites. As mentioned by VillaseñOr et al. (2000a), this ammonite assemblage typically characterizes the black silty limestone beds which are a clear stratigraphic reference in north-eastern areas of Mexico, mainly the Zacatecas-Saltillo region and the Cuencamé area (Durango), but also crop out in Coahuila and Nuevo León. In the Huasteca region of central-east Mexico several silty limestone beds also hold the record of the two ammonite genera –Glochiceras (Coryceras) carinatum (aguilera) and Procraspedites praecursor (burCkhardt) (lópez-gómez, 2006). Thus the two mentioned ammonite assemblages allow for wide-regional biostratigraphic correlation in Mexico (Fig. 3).Worthy of mention is the report made by Cantú-Chapa (1971, 1984) of his “Zona con Glochiceras del gr. fialar” in the Tamán area. From this area he also recorded Ochetoceras aff. canaliferum (Oppel), Glochiceras (Lingulaticeras) cf. nudatum (Oppel in ziegler, 1958), Taramelliceras (Metahaploceras) aff. nereus (FOntannes in burCkhardt), Aspidoceras gr. bispinoides burCkhardt (= Aspidoceras longispinum in CheCa, 1985, p. 76) and Subdichotomoceras mclachlani (burCkhardt) from a 40 to 80 m thick section, but unfortunately he did not provide stratigraphic precision about their relative positions. Cantú-Chapa (1971, 1984) recognized the reported ammonite assemblage as common in the Lower Kimmeridgian from central Mexico, with no additional information. Recently, Cantú-Chapa (2001) mentioned that the top of the Lower Kimmeridgian is characterized by the occurrence of genus Glochiceras in practically all Mexico. However, no conclusive interpretation is possible about the stratigraphic range of the interpreted taxon Glochiceras s.l. he is taking into account. On the assumption that Cantú-Chapa is considering the “Zona con Glochiceras del gr. fialar” mentioned previously by the author, a different biostratigraphic interpretation was previously put forward by Olóriz et al. (1998) and VillaseñOr et al. (2000a), who proposed correlation with a part of the standard Eudoxus Zone accepted for epicontinental, submediterranean Europe. This also applies to the ammonite horizon with Glochiceras (Coryceras) carinatum (aguilera) and Procraspedites praecursor (burCkhardt) (Fig. 3).


IV. NEW DATA ABOUT THE KIMMERIDGIAN-TITHONIAN BOUNDARY

As previously stated by VillaseñOr et al. (2000a), the precise identification of new as well as previously known microconchs of Hybonoticeras species analyzed by Olóriz and VillaseñOr (1999) and Olóriz et al. (2000) is the only available way for recognition of the Kimmeridgian/Tithonian boundary beds in the Mexican Altiplano. Lately new records of Hybonoticeras macro- and microconchs gathered from La Caja/La Casita Formation allow reinforcing a wider correlation potential (lópez-CaballerO, 2009). The records of Hybonoticeras sp. gr. beckeri (neumayr) and H. (Hybonotella) mundulum (Oppel) attenuatum berCkhemer & hölder (= Hybonoticeras mundulum sensu Olóriz et al., 2000), cited by lópez-CaballerO (2009) from the Coahuila state, expand the palaeobiogeographic range of Hybonoticeras in north-central Mexico. New data from central-east Mexico (Tamán Formation) refer to fragments of Hybonoticeras sp. from the Mazatepec area (VillaseñOr et al., 2000b). This record was interpreted as Late Kimmeridgian, Beckeri Chron, in age. North-westwards from Mazatepec, in Las Campanas area (Hidalgo State), Lingulaticeras sp. 1 aff. procurvum ziegler (Pl. I, fig. 15) confirms the biostratigraphic interpretation of these beds as belonging to the Beckeri or lowermost Hybonotum zones. Uppermost Kimmeridgian records of ziegler’s species were long-time reported from the Upper Kimmeridgian (Beckeri Zone) in southern Germany (ziegler, 1958), and similar forms were recently identified in Crimea (arkad’eV & rOgOV, 2006).All these new records expand the possibilities of a wide regional correlation and contradict the statement made by Cantú-Chapa (2001), who suggested a restricted paleogeographic distribution of Hybonoticeras around the Kimmeridgian/Tithonian boundary in central Mexico (= San Pedro del Gallo, Mazapil, and Symón sensu Cantú-Chapa, 2001, fig. 8). Unfortunately, the age and palaeobiogeographic distribution assumed by this author for Hybonotyceras records in Mexico did not take into account previously published information (VillaseñOr, 1991; Olóriz et al., 1993, 2000; Olóriz & VillaseñOr, 1999; VillaseñOr et al., 2000a).Until now no new records of Hybonoticeras of the hybonotum group have been obtained, and thus the precise interpretation and characterization of the Kimmeridgian/Tithonian boundary at the ammonite horizon level remains as an open question for future research.Two ammonite records relevant for supporting the identification of uppermost Kimmeridgian to lowermost Tithonian deposits in central-east Mexico, Huasteca region, are those of Taramelliceras kiderleni berCkhemer & hölder (Pl. I, figs. 16, 17) and Paralingulaticeras sp. 1 aff. parcevali (FOntannes) (Pl. I, fig. 10-12), the former

being stratigraphically more restricted (Fig. 3 and 4). In fact, T. kiderleni has been reported from the uppermost Kimmeridgian Beckeri Zone in southern Germany (from berCkhemer & hölder, 1959 to sChweigert et al., 1996). P. parcevali, and close relatives, offer a longer biostratigraphic range (upper part of the Beckeri Zone to Hybonotum Zone, more or less complete according to authors, and equivalent biostratigraphic units), throughout a wider palaeobiogeographic distribution that largely exceeds intertropical latitudes, especially northwards (from FOntannes, 1879 to ziegler, 1958; berCkhemer & hölder, 1959; COllignOn, 1959 and rOgOV, 2002). Another related example for recognition of stratigraphic intervals close to the Kimmeridgian/Tithonian boundary is that of the complementary, single record of Schaireria neumayri CheCa (Pl. I, figs. 13, 14), known from Mazatepec, which reveals faunal influence from the westernmost Tethys, since this species seems to be only known from southern Iberia, the Majorca Island and the Venetian Alps (CheCa, 1985; sarti, 1993; CaraCuel & Olóriz, 1999; CaraCuel et al., 1998).

V. TITHONIAN

After the biostratigraphic synthesis published by VillaseñOr et al. (2000a), the single new record of Mazapilites outside central-east and north-eastern Mexico, belongs to a distant area in north-western Mexico, at Cucurpe (Sonora State). VillaseñOr et al. (2005) reported Mazapilites mexicanus (aguilera) associated to Schaireria neoburgensis (Oppel) and Glochiceras (Lingulaticeras?) sp. below the record of Pseudodiscosphinctes sp. This new record of Mazapilites outside the previously known geographical range (burCkhardt, 1906; Cantú-Chapa, 1971, 1984; hernández-Fuente, 1996) expands the possibilities of correlation in northern and east-central Mexico (Fig. 4). Its associated record with Schaireria neoburgensis (Oppel) will deserve special attention in terms of the correlation potential with areas outside Mexico (Fig. 4).No new information from the Lower Tithonian assemblage labelled as Usseliceras-Franconites assemblage by VillaseñOr et al. (2000a) exists. However, VillaseñOr et al. (2005) reported the presence of Torquatisphinctes subbleicheri (burCkhardt), Torquatisphinctes sp. cf. T. diversecostatus (burCkhardt), and Torquatisphinctes sp. cf. T. lauri (aguilera) from stratigraphic horizons overlying Pseudodiscosphinctes sp. in the same area in Cucurpe. Poor preservation limited palaeontological analysis and biostratigraphy but these authors assigned an early Tithonian age (corresponding to the middle to upper Albertinum/Darwini or lowermost part of Semiforme/Verruciferum Zone) to the studied ammonites, and interpreted the registered assemblage as potential correlative of the Parastreblites-Torquatisphinctes assemblage established by VillaseñOr et al. (2000a).


Part 1

Fig. 3: Correlation chart for the Kimmeridgian (Part 1 and 2). Selected proposals for ammonite biostratigraphy in Mexico, in chronological order from left to right.

Part. 1 with narrow grey boxes showing original stage/substage level bio-chronostratigraphic interpretations in the corresponding author(s) columns (see part 2 for complementary information)


Part 2

Part. 2 shows interpretations of discrete biostratigraphic units. New data obtained by the authors are retrieved after 2000. Ammonite assemblages in grey for biostratigraphic interpretations without precise reference at the zone level. Broken lines indicate no precise biostratigraphic range for the ammonite assemblages involved. European standards on the left slightly adapted from CariOu & hantzpergue (1997) with absolute age datum according to the ISChart 2009 (www.stratigraphy.org; gradstein et al., 2004). On the right column, short broken lines indicate correlation with European Standard Zone boundaries. Ammonite horizons represented as in Fig. 2.

http://www.stratigraphy.org


Part 1

Fig. 4: Correlation chart for the Tithonian (Part 1 and 2). Selected proposals for ammonite biostratigraphy in Mexico, in chronological order from left to right.

Part. 1 with narrow grey boxes showing original stage/substage level bio-chronostratigraphic interpretations in the corresponding author(s) columns (see part 2 for complementary information).


Part 2

Part 2 shows interpretations of discrete biostratigraphic units except for Cantu-Chapa’s columns. New data from the authors are retrieved after 2000. Ammonite assemblages in grey for biostratigraphic interpretations without precise reference at the zone level. Broken lines indicate no precise biostratigraphic range for the ammonite assemblages involved. Gray shaded triangles for partial occurrence of ammonite genera/assemblages of Berriasian age and/or extending into the Berriasisan. European standards on the left slightly adapted from CariOu & hantzpergue (1997) with absolute age datum according to the ISChart 2009 (www.stratigraphy.org; gradstein et al., 2004). On the right column, short broken lines indicate correlation with European Standard Zone boundaries. Ammonite horizons represented as in Fig. 2.



Most probably, the ammonite record under consideration represents a part of the mentioned ammonite assemblage (Fig. 4).As was mentioned by VillaseñOr et al. (2000a), the Andiceras-Kossmatia assemblage is typical of condensed deposits named by burCkhardt (1906) as “Calcaires phosphoritiques grisâtres”, as well as of the so-called “Virgatosphinctinae beds” by Verma and westermann (1973). On the basis of the ammonites identified by Olóriz et al. (1996, 1999), this assemblage evidences the Semiforme/Verruciferum Chron stratigraphic interval, assuming the possibility for including the earliest Richteri Chron. Concerning the biochronostratigraphic and palaeobiogeographic interpretation of this assemblage, later data of VillaseñOr et al. (2003, 2011) and VillaseñOr & Olóriz (2004, 2009, 2010) improved the previous information given by VillaseñOr et al. (2000a). In fact, ammonites from the same age were collected in “normal facies” of silty limestones (i.e., non-condensed deposits or “Virgatosphinctinae beds” in VillaseñOr & Olóriz, 2010) cropping out in the Mazatepec region, where VillaseñOr et al. (2003, 2011) identified Simocosmoceras pszczolkowskii apulcoensis VillaseñOr & Olóriz, Pseudovolanoceras aesinensis chignahuapensis (Cantú-Chapa), and Pseudovolanoceras aesinensis (meneghini), and VillaseñOr & Olóriz (2004, 2009) recognized Pseudhimalayites steinmanni (haupt) (Pl. I, fig. 18-20) and Housaites butti (imlay). All these ammonite records support restriction of the age to the Semiforme/Verruciferum Chron (Fig. 4), at least in the Huasteca region investigated.Increased endemism in ammonites, and the difficulty for calpionellids to favourably preserve in silty deposits, commonly limit accurate biostratigraphic interpretations. Bed-by-bed sampling in progress on several outcrops corresponding to the upper part of the La Caja/La Casita Formation and lateral equivalents in central-eastern Mexico (i.e., Pimienta and Chinameca Formations) will provide new information in the near future. At present, only few new data are valuable for precise biostratigraphic characterization of Upper Tithonian outcrops. In the Mazatepec area lópez-CaballerO et al. (2007) recognized three ammonite horizons in the lower part of the Pimienta Formation (Fig. 4), which from the youngest to the oldest are: (i) Suarites bituberculatum Cantú-Chapa and Wichmanniceras cf. hernandense Cantú-Chapa; (ii) Suarites and Corongoceras, both genera being represented by several species; and (iii) Suarites sp. cf. floreslopezi Cantú-Chapa and Corongoceras sp. cf. lotenoense (spath) -mendozanum (behrendsen). In the latter, a new species of Corongoceras, together with Mazatepites arredondense Cantú-Chapa, was registered, but no record of calpionellids were available (ecologic or preservational bias?). For the same stratigraphic horizons, the combined record of ammonite specimens of the Corongoceras lotenoense (spath) -

mendozanum (behrendsen) group and Wichmanniceras cf. hernandense Cantú-Chapa were interpreted as belonging to the Upper Tithonian Simplisphinctes Zone (Fig. 4). The combined record of Mazatepites with Upper Tithonian ammonites deserves attention. Cantú-Chapa (1967, p. 7) interpreted a mid-Tithonian age for his new genus Mazatepites collected from the “Afloramiento nº 4” at the base of the Pimienta Fm., “Unidad con Kossmatia victoris y Pseudolissoceras zitteli” in the Mazatepec area, km 33.900 of the road from Tlatlauqui to Mazatepec. This author used this precise location to show the Middle/Upper Tithonian boundary (Cantú-Chapa, 1967, fig. 5) – i.e., the boundary between the “Unidad con Kossmatia victoris y Pseudolissoceras zitteli” below and the “Unidad con Suarites bituberculatum” above. Hence, it could be inferred that Mazatepites was just overlain by Upper Tithonian deposits in the “Afloramiento nº 4”, although no ammonites of the latter Upper Tithonian assemblage mentioned (Cantú-Chapa, 1967, p. 20) were retrieved from that outcrop. Instead, Upper Tithonian ammonites were collected from the separate outcrop called “Afloramiento nº 3”. Unfortunately, the author did not provided precise biostratigraphy for specimens collected from his 4 m thick “Unidad con Kossmatia victoris y Pseudolissoceras zitteli” (Cantú-Chapa, 1967, p. 21), which he later interpreted at biostratigraphic zone level (Cantú-Chapa, 1971, p. 29). Recently, Cantú-Chapa (2009b, p. 3) mentioned that his original interpretation of the “Unidad” or Zone with Kossmatia victoris and Pseudolissoceras zitteli was Lower Tithonian (not Middle Tithonian as quoted above) and mentioned that the two original specimens of Mazatepites (Ac-89 as holotype and Ac-90 as paratype in Cantú-Chapa, 1967, p. 7) were collected from the same Bed 4, which is also referred as locality (Cantú-Chapa, 2009b, fig. 1), and originally as “Afloramiento nº 4” (Cantú-Chapa, 1967, p. 6, 7, 18, 21). Moreover, Cantú-Chapa (2009b, fig. 1c) reinterpreted his zone with Kossmatia victoris and Pseudolissoceras zitteli as the base of the Upper Tithonian in Mexico, Cuba and southern USA.The combined record of Mazatepites? sp. A and Corongoceras? sp. A has been reported by parent et al. (2011) from the Neuquén-Mendoza Basin, where these authors interpret a rather indeterminate mid-Tithonian age. In fact, parent et al. (2011, p. 82 and 86) indicate that the major part of the ammonite assemblage in the single biohorizon identified in the Proximus Zone (i.e., the Cieneguiticeras falculatum) are long-ranging species, being the recognition of ammonite assemblages belonging to the Zitteli and Internispinosum zones crucial for clarifying biostratigraphy. In fact, the Internispinosum Zone directly overlies the youngest record of Mazatepites reported by parent et al. (2011), together with Toulisphinctes cf. rafaeli (Oppel) – youngest known records in the Tethyan Burckhardticeras/Ponti Zone – and Corongoceras? sp. A (without tubercles), while


Micrancanthoceras is known from the directly overlying lowermost horizons of the Internispinosum Zone, which does not show relevant changes in lithofacies other than the occurrence of calcareous concretions. Hence, it seems reasonable to envisage that an upper-to-uppermost part of the Proximus Zone could be youngest-Early to earliest-Late Tithonian in age (two-fold division), thus reinforcing an early Late Tithonian age for the lower part of the Internispinosum Zone as interpreted by Olóriz & taVera (1989), who favoured the first occurrence of himalayitids to be used to mark the beginning of the Late Tithonian. Later interpretations based on Argentinean ammonites and favouring an early Late Tithonian age for the Windhauseniceras internispinosum Biozone have been published (e.g., leanza, 1996; zeiss & leanza, 2008).On the basis of the above and following lópez-CaballerO et al. (2007), we interpret that the record of Mazatepites identified in the lowermost ammonite horizon registered in the Mazatepec area (see above) could be restricted to the uppermost Lower Tithonian (two-fold division) and, hence, its combined record with Corongoceras and Suarites most probably resulted from taphonomic condensation (lópez-CaballerO et al., 2007, p. 248). Cantú-Chapa (2009b) misinterpreted the biochronostratigraphic discussion in lópez-CaballerO et al. (2007) and reallocated his holotype and paratype specimens of Mazatepites in two distinct families of Perisphinctoidea without mention to the polyphyletic character assumed by lópez-CaballerO et al. (2007, p. 246, 248) for Mazatepites as originally proposed by Cantú-Chapa (1967).According to the interpretations above, the correlation proposed by Cantú-Chapa (1967) of his “Unidad con Suarites bituberculatum” in the lower part of his Upper Tithonian, associated with Wichmanniceras and without record of microfossils, with de Berriasian interval corresponding to the Delphinensis Zone from southeastern France cannot apply. In contrast, the correlation proposed by Cantú-Chapa (1967) with the Alternans horizon from Argentina, as considered by this author, could be basically correct if restricted to the lower part of this biozone in Argentina, as interpreted by parent (2003; but see references therein). Notwithstanding, we interpret that the lowermost part of the Alternans Zone is younger than the base of the Upper Tithonian in Argentina. The interpretation for the M17 horizon (“Suarites beds”) made by CallOmOn (1992) as the upper part of the Microcanthum Zone within the Upper Tithonian results younger than it was interpreted by Olóriz & taVera (1989) and parent (2001).Cantú-Chapa (2006) published a newly collected ammonite fauna from southern Veracruz, central Mexico. The author recognized many endemic taxa at the genus and species levels, and interpreted their age as Late Tithonian. Unfortunately, the ammonite fauna was represented by fragments and incomplete shells, mainly phragmocones,

as can be seen from the illustrated specimens and descriptions in his text, and the most important limitation for biochronologic and biostratigraphic correlation is the lack of precise stratigraphic or biostratigraphic control applied to ammonites collected at the Chinameca quarry.

VI. COMMENTS ABOUT THE UPPERMOST TITHONIAN AND THE TITHONIAN/BERRIASIAN BOUNDARY

The research in sections sampled bed-by-bed in NE and SE Mexico is in progress by our team, but no significant new data have been published after 2000. In accordance with the interpretation made by VillaseñOr et al. (2000a), there is increasing evidence for the real difficulty in both the precise correlation of ammonite assemblages from the upper part of the Tithonian and the precise identification of the Jurassic/Cretaceous boundary, as usually interpreted on the basis of calpionellid and ammonite assemblages elsewhere (see the introductory chapter for paleoenvironmental remarks). Notwithstanding, papers published in the nineties clearly indicated that (i) particular ammonite genera (e.g., Paradontoceras and/or Substeueroceras, Durangites, and specimens usually referred to Kossmatia included), and ammonite assemblages, traditionally considered as Upper Tithonian in Mexico should extend into the Berriasian; and (ii) calpionellid assemblages in use for global correlation in fact apply for characterizing stratigraphic horizons in Mexico, with increasing resolution within the Tithonian to the southeast. A revision and wide regional review for evaluating the correlation potential of ammonite and calpionellid assemblages in Mexico, and with respect to correlation with Caribbean, Central North Atlantic and Mediterranean (Tethyan s. str.) and palaeogeographically related areas can be found in Olóriz et al. (2003 and references therein). Complementary information about the situation eastwards in the southeastern Gulf of Mexico region and the North American passive palaeomargin outcropping in Cuban areas can be found in CObiella & Olóriz (2009). These authors reinterpreted published calpionellid data showing analogous difficulty in the precise identification of the Tithonian/Berriasian boundary according to published information, even considering cases of combined assemblages of ammonites and calpionellids, but the correlation potential of the latter is demonstrated.

VII. FINAL REMARKS ON BIOSTRATIGRAPHY, BIOCHRONOSTRATIGRAPHY AND CORRELATION

The bed-by-bed sampling performed by the authors since 1985 in Mexico demonstrates how much local ammonite biostratigraphy deviates from repetition of


precise homotaxial successions. Hence we assume that ammonite biostratigraphy and correlation depend on the palaeoenvironmental context outlined above, forcing largely irregular spatial-temporal frames for ammonite species inhabiting Mexican shelves. Thus, recognition of discrete biostratigraphic units is common. As expected, limitations to homotaxy oppose the taxonomic level of reference. From local ammonite records to consistent ammonite assemblages (faunal horizons), reproducibility is often limited in a variable degree. In order to update Upper Jurassic ammonite biostratigraphy in Mexico we differentiate among local (section level), regional (more or less wide regions in Mexico), and standard (inter-regional at least for Mexico) faunal horizons (see Figs. 2 to 4 for correlation potential assessments). These faunal – ammonite – horizons are clearly distinct from biohorizons interpreted according to NASC and to the International Stratigraphic Guide definitions. In fact, the identified ammonite horizons are embedded in 3D sedimentary packages of variable thickness and are separated by barren intervals, the latter as considered in the NASC and ICS recommendations. At present, any precise biochronologic interpretation of these faunal ammonite horizons taking standard European biochronozones as reference remains tentative.Interesting in the palaeoenvironmental context described in the introductory chapter is the weak relationships we recognize between the type – order – of faunal horizon considered and its potential for correlation outside Mexico. We interpret this feature of ammonite records in the Upper Jurassic from Mexico as revealing a variable degree of endemism.

VIII. CONCLUSIONS

On the basis of new data, Middle Oxfordian precise biostratigraphy is added to the refinement of ammonite assemblages formally established by VillaseñOr et al. (2000a). The biostratigraphic updating is performed in terms of ammonite horizons prearranged according to three levels of occurrence – local, regional, and inter-regional within Mexico (Figs. 2-4), which offers variable correlation potential with areas outside Mexico.The progress with Upper Jurassic ammonite biostratigraphy in Mexico reveals a common difficulty for recognition of homotaxial successions to approach precise correlations, and local paleoenvironmental conditions are assumed as largely responsible for this. Scattering of discontinuous, precise ammonite records dominate. Future research is necessary before an optimal synthesis for Upper Jurassic Mexican biostratigraphy can be available in terms of both precise ammonite horizons and the precise identification of the Tithonian/Berriasian boundary.

ACKNOWLEDGEMENTS

This research was made within the collaboration project between the Department of Palaeontology of the UNAM (Mexico) and the Department of Stratigraphy and Palaeontology of the University of Granada (Spain), with financial support of DGAPA (UNAM, Mexico; Project IN105311-3) and the EMMI Group (RNM-178 Junta de Andalucía, Spain). We acknowledge José sandOVal (University of Granada, Spain) and an anonymous referee for the revision of an early draft of the manuscript.

REFERENCES

arkad’eV, V.V. & m.a. rOgOV (2006) - New Data on Upper Kimmeridgian-Tithonian Biostratigraphy and Ammonites of the Eastern Crimea. Stratigraphy and Geological Corre-lation, 14(2): 185-199.

berCkhemer, F. & h. hölder (1959) - Ammonites aus dem Oberen Weissen Jura Süddeutschlands. Beihefte zum Geo-logischen Jahrbuch, 35: 135 p.

burCkhardt, C. (1906) - La faune Jurassique de Mazapil avec un appendice sur les fossiles du Crétacique inférieur. Boletín del Instituto Geológico de México, 23: 1-217.

burCkhardt, C. (1930) - Étude synthétique sur le Mésozoïque mexicain. Mémoires de la Société Paléontologique Suisse, 49-50: 1-280.

CallOmOn, J.H. (1992) - Upper Jurassic, especially Mexico. In: westermann, g.e.g. (ed.), The Jurassic of the Cir-cum Pacific, part 4. Biochronology 12. Cambridge Univer-sity Press, New York: 261-272.

Cantú-Chapa, A. (1967) - El límite Jurásico-Cretácico en Mazatepec, Puebla. Estratigrafía del Jurásico de Mazate-pec, Puebla (México). Instituto Mexicano del Petróleo, Sección Geología, Monografía, 1: 3-24.

Cantú-Chapa, A. (1969) - Estratigrafía del Jurásico Medio-Superior del subsuelo de Poza Rica, Veracruz (Área de Soledad-Miquetla). Revista del Instituto Mexicano del Petróleo, 1(1): 3-9.

Cantú-Chapa, A. (1971) - La Serie Huasteca (Jurásico Medio-Superior) del centro este de México. Revista del Instituto Mexicano del Petróleo, 3(2): 17-40.

Cantú-Chapa, A. (1976) - Nuevas localidades del Kimerid-giano y Titoniano de Chihuahua (Norte de México). Revista del Instituto Mexicano del Petróleo, 8(2): 38-45.

Cantú-Chapa, A. (1979) - Bioestratigrafía de la Serie Huas-teca (Jurásico Medio y Superior) en el subsuelo de Poza Rica, Veracruz. Revista del Instituto Mexicano del Petróleo, 11: 14-24.

Cantú-Chapa, A. (1982) - The Jurassic-Cretaceous boundary in the subsurface of eastern Mexico. Journal of Petroleum Geology, 4(3): 311-318.

Cantú-Chapa, A. (1984) - El Jurásico Superior de Tamán, San Luis Potosí, Este de México. Memoria del III Congreso Latinoamericano de Paleontología, México: 207-212.

Cantú-Chapa, A. (1999) - Confrontation of stratigraphic methods to define the Jurassic-Cretaceous boundary in eas-tern Mexico subsurface. Geological Society of America Special Paper, 340: 93-103.

Cantú-Chapa, A. (2001) - Mexico as the western margin of


Pangea based on biogeographic evidence from the Permian to the Lower Jurassic. In: bartOlini, C., r.t. buFFler & a. Cantú-Chapa (eds.), The western Gulf of Mexico Basin: Tectonics, sedimentary basins, and petroleum sys-tems. American Association of Petroleum Geologists Memoir, 75: 1-27.

Cantú-Chapa, A. (2003) - Subsurface mapping and structural elements of the top Jurassic in eastern Mexico (Poza Rica and Tampico districts). In: bartOlini, C., R.T. buFFler & J. bliCkwede (eds.), The Circum-Gulf of Mexico and the Caribbean: Hydrocarbon habitats, basin formation, and plate tectonics: American Association of Petroleum Geolo-gists Memoir, 79: 330-339.

Cantú-Chapa, A. (2006) - New Upper Tithonian (Jurassic) ammonites from the Chinameca Formation in southern Veracruz, eastern Mexico. Journal of Paleontology, 80(2): 294-308.

Cantú-Chapa, A. (2009a) - Upper Jurassic stratigraphy (Oxfordian and Kimmeridgian) in petroleum wells of Campeche Shelf, Gulf of Mexico. In: bartOlini, C. & J.r. rOmán ramOs (eds.), Petroleum systems in the southern Gulf of Mexico. American Association of Petroleum Geo-logists Memoir, 90: 79-91.

Cantú-Chapa, A. (2009b) - Some Perisphinctid ammonites of the Tithonian (Jurassic) from Eastern Mexico – Systematic considerations. PetroQuiMex, revista de la industria petro-lera: 2-20.

CaraCuel, J.E. & F. Olóriz (1999) - Recent data on the Kim-meridgian-Tithonian boundary in the Sierra Norte of Mal-lorca (Spain), with notes on the genus Hybonoticeras breistrOFFer. Geobios, 32(4): 575-591.

CaraCuel, J.E., F. Olóriz & C. sarti (1998) - Updated bios-tratigraphy of the Kimmeridgian and Lower Tithonian at Lavarone (Trento Plateau, Italy). Correlation for epio-ceanic Western Tethys. Geologica et Paleontologica, 32: 235-251.

CariOu, R. & P. hantzpergue (eds.) (1997) - Groupe Français d’Études du Jurassique, biostratigraphie du Jurassique Ouest-Européen et Méditerranéen. Zonations parallèles et distribution des invertébrés et microfossiles. Groupe Fran-çais Étude Jurassique. Bulletin du Centre de Recherches Elf Exploration-Production Mémoire, 17: 1-400.

CheCa, A. (1985) - Los aspidoceratiformes en Europa (Ammo-nitina, Fam. Aspidoceratidae: Subfamilias Aspidocerati-nae y Physodoceratinae). PhD. Thesis, Universidad de Granada, Facultad de Ciencias, 516 p.

CObiella-reguera, J.L. & F. Olóriz (2009) - Oxfordian – Berriasian stratigraphy of the North American paleomargin in western Cuba: Constraints for the geological history of the proto-Caribbean and the early Gulf of Mexico. In: bartOlini, C. & J.R. rOmán ramOs (eds.), Petroleum systems in the southern Gulf of Mexico. American Asso-ciation of Petroleum Geologists, Memoir, 90: 421-451.

COllignOn, M. (1959) - Atlas des fossiles caractéristiques de Madagascar (Kimmeridgien). Ministères des Mines et de l’Energie. République Malgache. Tananarive, Fascículo 5, pl. 96-133.

COntreras y mOnterO, b., a. martínez-COrtes & m.e. gómez-luna (1988) - Bioestratigrafía y sedimentología del Jurásico Superior en San Pedro del Gallo, Durango, México. Revista del Instituto Mexicano del Petróleo, 20(3): 5-49.

FOntannes, F. (1879) - Description des Ammonites des Cal-

caires du Château de Crussol-Ardèche (Zones à Oppelia tenuilobata et Waagenia beckeri). Travaux de la Université de Lyon: 1-22.

gradstein, F.m., J.g. Ogg, a.g. smith, F.p. agterberg, w. bleeker, r.a. COOper, V. daVydOV, p.gibbard, l.a. hinnOV, m.r. hOuse, l. lOurens, h-p. luterbaCher, J. mCarthur, m.J. melChin, l.J. rObb, J. shergOld, m.VilleneuVe, b.r. wardlaw, J. ali, h. brinkhuis, F.J. hilgen, J. hOOker, r.J. hOwarth, a.h. knOll, J. laskar, s. mOneChi, J. pOwell, k.a. plumb, i. raFFi, u. röhl, a. sanFilippO, b. sChmitz, n.J. shaCkletOn, g.a. shields, h. strauss, J. Van dam, J. Veizer, th. Van kOlFsChOten & d. wilsOn (2004) - A Geologic Time Scale 2004. Cambridge University Press, and the offi-cial website of the International Commission on Stratigra-phy (ICS) under www.stratigraphy.org, ISChart2009.

hernández-Fuente de la, R. (1996) - Sedimentología y diagé-nesis del kimmeridgiano en la Región de Jonotla, Puebla y Tlacolula, Veracruz. Master degree Thesis, Universidad Nacional Autónoma de México: 82 p. (unpublished)

imlay, R.W. (1939) - Upper Jurassic Ammonites from Mexico. Bulletin of the Geological Society of America, 50: 1-78.

imlay, R.W. (1943) - Upper Jurassic Ammonites from Placer de Guadalupe District, Chihuahua, Mexico. Journal of Paleontology, 17: 527-543.

imlay, R.W. (1980) - Jurassic Paleobiogeography of the conter-minous United States in its continental setting. U. S. Geo-logical Survey Professional Paper, 1062: 1-134.

imlay, R.W. (1984) - Jurassic ammonite successions in North America and biogeographic implications. In: wester-mann, G.E.G. (ed.), Jurassic-Cretaceous biochronology and paleontology of North America. Geological Associa-tion of Canada, Special paper, 27: 1-12.

Jiménez-lópez, J.C. (2011) - Sistemática y bioestratigrafía de ammonites del Jurásico Superior de Tamán, San Luís Potosí, México. Undergraduate Thesis, Facultad de Cien-cias, Universidad Nacional Autónoma de México: 77 p. (unpublished)

Leanza, h.a. (1996) - The Tithonian genus Chigaroceras Howarth (1992) as a bioevent marker between Iraq and Argentina. In: riCCardi, A.C. (ed.), Advances in Jurassic Research, GeoResearch Forum, 1-2: 451-458.

lópez-CaballerO, I. (2009) - Bioestratigrafía y Tafonomía de la sección estratigráfica Puerto Piñones (Jurásico Supe-rior) del área de Saltillo, Coahuila, México. Master degree Thesis, Posgrado en Ciencias de la Tierra, Instituto de Geo-logía, Universidad Nacional Autónoma de México: 169 p. (unpublished)

lópez-CaballerO, i., a.b. VillaseñOr & F. Olóriz sáez (2007) - Sobre una asociación de ammonites del Jurásico Superior (Tithonico) de Mazatepec, Puebla, México. In: díaz-martínez, e. & i. rábanO (eds.). 4th European Meeting on the Palaeontology and Stratigraphy of Latin America. Instituto Geológico y Minero de España, Madrid. Cuadernos del Museo Geominero, 8: 245-249.

lópez-gómez, P. (2006) - Estudio de la fauna de ammonites del Jurásico Superior (Kimmeridgiano) en una sección estratigráfica en el Noroeste del Estado de Hidalgo, México. Undergraduate Thesis, Facultad de Ciencias, Uni-versidad Nacional Autónoma de México: 113 p. (unpublished)

lópez-palOminO, i. (2002) - Análisis bioestratigráfico basado en fauna de ammonites del Oxfordiano (Jurásico Superior)



en la región de Tamán, San Luis Potosí. Master degree Thesis, Posgrado en Ciencias de la Tierra, Instituto de Geo-logía, Universidad Nacional Autónoma de México: 174 p. (unpublished)

lópez-palOminO, i., a.b. VillaseñOr & F. Olóriz (2006) - Primer registro del género Vinalesphinctes (Ammmo-nitina) en el Oxfordiano de México: Significación bioestratigráfica y consideraciones paleobiogeográficas en el Jurásico Superior de América. Revista Mexicana de Ciencias Geológicas, 23(2): 162-183.

myCzynski, r., F. Olóriz & a.b. VillaseñOr (1998) - Bios-tratigraphy and correlations of the Middle-Upper Oxfor-dian in the Americas (southern USA, Mexico, Cuba, and northern Chile). Neues Jahrbuch für Geologie und Paläon-tologie, Abhandlungen, 207(2): 185-206.

Olóriz, F. (1987) - El significado biogeográfico de las platafor-mas mexicanas en el Jurásico superior. Consideraciones sobre un modelo eco-evolutivo. Revista de la Sociedad Mexicana de Paleontología, 1(1): 219-247.

Olóriz, F. (1992) - North-Central and eastern Mexico. In: westermann, g.e.g. (ed.), The Jurassic of the Circum Pacific, part 3. Regional geology and stratigraphy 5. Cam-bridge University Press, New York: 100-107.

Olóriz, F. & J.m. taVera (1989) - The significance of Medi-terranean ammonites with regard to the traditional Jurassic-Cretaceous boundary. Cretaceous Research, 10: 221-237.

Olóriz, F. & a.b. VillaseñOr (1999) - New microconchiate Hybonoticeras from Mexico. Geobios, 32(4): 561-573.

Olóriz, F. & a.b. VillaseñOr (2006) - Ceratosphinctes (Ammonitina, Kimmeridgian) in Mexico: from rare but typical inhabitant of west-Tethyan epioceanic and epi-continental waters to a widespread ammonite genus. Geo-bios, 36: 255-266.

Olóriz, F., a.b. VillaseñOr, C. gOnzález-arreOla & g.e.g. westermann (1990a) - Las plataformas mexica-nas durante el Jurásico superior. Un ejemplo de áreas de recepción en biogeografía. Actas de las IV Jornadas de Paleontología, Salamanca, España. Actas de Paleontolo-gía, 4: 277-287.

Olóriz, F., a.b. VillaseñOr, C. gOnzález-arreOla & g.e.g. westermann (1990b) - Problems of litho-correla-tion in the Mexico-Caribbean area and the significance of upper Oxfordian “Discosphinctes”. Publicaciones del Seminario de Paleontología de Zaragoza, 2: 191-204.

Olóriz, F., l. lara, a. de la mOra, a.b. VillaseñOr & C. gOnzález-arreOla (1993) - The Kimmeridgian/Titho-

Plate I

Fig.1: Gregoryceras sp. gr. riazi (grOssOuVre). IGM-6548, fragment showing a left side view of immature specimen. From ILR section, Las Choapas area, Veracruz, Mexico.

Fig. 2: Ochetoceras (Cubaochetoceras) sp. gr. mexicanum (burCkhardt)-burckhardti (O’COnnell). IGM-6549, left side view of incomplete, immature specimen. From ILR section, Las Choapas area, Veracruz, Mexico.

Fig. 3: Ochetoceras sp. cf. hispidum (Oppel). IGM-6550, left side view of inner whorls. From ILR section, Las Choapas area, Veracruz, Mexico.

Fig. 4: Neocampylites delmontanus (Oppel). IGM-6551, left side view of immature specimen. From ILR section, Las Choapas area, Veracruz, Mexico.

Fig. 5: Mirosphinctes sp. gr. frickensis (mOesCh). IGM-6552, evolute specimen with coarse ribbing. Right side view with arrows for parabolae and lappet. From ILR section, Las Choapas area, Veracruz, Mexico.

Fig. 6: Euaspidoceras oconnellae (sanChéz-rOig). IGM-6553, right side view of incomplete specimen. From TAM-1 section, San Luis Potosí, Mexico.

Figs. 7, 8: “Subdiscosphinctes” sp.1 gr. carribeanus (JawOrski). 7, IGM-6554, right side view of incomplete specimen showing ca. 1/8 of the last whorl of body chamber; 8, IGM-6555, left side view of inner whorls. From TAM-1 section, San Luis Potosí, Mexico.

Fig. 9: Ataxioceras sp. [M] of the hypselocyclum-discoidale morphological plexus. IGM-6556, left side view of the inner-middle whorls. From TAM-1 section, San Luis Potosí, Mexico.

Figs. 10, 11, 12: Paralingulaticeras sp. 1 aff. parcevali (FOntannes). 10-11, IGM-6557, right side and ventral views. 12, IGM-6558, left side view. From MTQ-1 section, Mazatepec area, Puebla, Mexico.

Figs. 13, 14: Schaireria neumayri CheCa. IGM-6559, right lateral and ventral views of inner whorls showing typical ventral undulation or shell corrugation. From MTQ-1 section, Mazatepec area, Puebla, Mexico.

Fig. 15: Lingulaticeras sp. 1 aff. procurvum ziegler. IGM-6560, right side view. From Las Campanas section, Hidalgo, Mexico.

Figs. 16, 17: Taramelliceras kiderleni berCkhemer & hölder. IGM-6561, left lateral and ventral views of immature specimen. From MTQ-1 section, Mazatepec area, Puebla, Mexico.

Figs. 18, 19, 20: Pseudhimalayites steinmanni (haupt). IGM-6562, ventral view showing the whorl section, left lateral view, and ventral view of the inner whorls. From MTQ-1 section, Mazatepec area, Puebla, Mexico.

Black scale bars (= 10 mm). All the material is housed in the National Paleontological Collection, Geological Museum (IGM) of the Universidad Nacional Autónoma de México (UNAM).

Plate I


nian boundary in the “Barranquito del Alacrán” section at Cuencamé (Durango, Mexico); its biostratigraphy and ecostratigraphic interpretation. Acta Geologica Polonica, 43(3-4): 273-288.

Olóriz, F., a.b. VillaseñOr, C. gOnzález-arreOla & g.e.g. westermann (1996) - Interpreting updated ammonite biostratigraphy. The Upper Jurassic-lowermost Cretaceous in the Alamitos area, Sierra de Catorce, San Luis Potosí (North-Central Mexico). Abstract volume IV International Symposium Cephalopods- Present and Past, Granada, España, Abstracts: 134-136.

Olóriz, F., a.b. VillaseñOr & C. gOnzález-arreOla (1998) - Re-evaluation of Procraspedites Spath, 1930 (Ammonitina) from the upper Kimmeridgian of Mexico. Bulletin de la Société Géologique de France, 169(2): 243-254.

Olóriz, F., a.b. VillaseñOr, C. gOnzález-arreOla & g.e.g. westermann (1999) - Ammonite biostratigraphy and correlations in the late Jurassic - earliest Cretaceous La Caja Formation of north-central Mexico. (Sierra de Catorce, San Luis Potosí). In: Olóriz, F. & F.J. rOdrí-guez-tOVar (eds.), Advancing Research in Living and Fossil Cephalopods. Kluwer Academic / Plenum Publishers, New York: 463-492.

Olóriz, F., a.b. VillaseñOr & C. gOnzález-arreOla (2000) - Geographic Control on phenotype expression. The case of Hybonoticeras mundulum (Oppel) from the Mexi-can Altiplano. Lethaia, 33(3): 157-174.

Olóriz, F., a.b. VillaseñOr & C. gOnzález-arreOla (2003) - Major lithostratigraphic units in land-outcrops of north-central Mexico and the subsurface along the northern rim of the Gulf of Mexico Basin (Upper Jurassic-lower-most Cretaceous): a proposal for correlation of tectono-eustatic sequences. Journal of South American Earth Sciences, 16: 119-142.

Olóriz, F., a.b. VillaseñOr & i. lópez-palOminO (2008) - Oxfordian ammonites from the lower part of the Santiago Formation at the type-section, Moctezuma river, Tamán, San Luis Potosí (Mexico). Revista Mexicana de Ciencias Geológicas, 25 (2): 261-283.

Olóriz, F., a.b. VillaseñOr & m. graJales-nishimura (2010) - New finding of genus Gregoryceras Spath 1924 (Ammonitina) from SE Mexico, Veracruz. In: ruiz-OmeñaCa, J.i., l. piñuela & J.C. garCía-ramOs (eds.), Comunicaciones del V Congreso del Jurásico de España. Museo del Jurásico de Asturias (MUJA), Colunga: 112-114.

parent, H. (2001) - The middle Tithonian (Upper Jurassic) ammnoid fauna of Cañadón de los Alazanes, southern Neu-quen-Mendoza Basin, Argentina. Boletín del Instituto de Fisiografía y Geología, 71(1-2): 19-38.

parent, H. (2003) - Taxonomic and biostratigraphic re-evalua-tion of Perisphinctes internispinosus krantz, 1926 (Upper Jurassic, Ammonoidea). Palaontologische Zeits-chrift, 77(2): 353-360.

parent, H., A. sCherzinger & g. sChweigert (2011) - The Tithonian-Berriasian ammonite fauna and stratigraphy of Arroyo Cieneguita, Neuquén-Mendoza Basin, Argentina. Boletín del Instituto de Fisiografía y Geología, 79-81: 21-94.

przybylski, P.A., E. Głowniak, J.G. Ogg, P. Ziółkowski, M. sidOrCzuk, J. gutOwski & M. lewandOwski (2010) - Oxfordian magnetostratigraphy of Poland and its

correlation to Sub-Mediterranean ammonite zones and marine magnetic anomalies. Earth and Planetary Science Letters, 289: 417-432.

rangin, C. (1977) - Sobre la presencia de Jurásico Superior con amonites en Sonora septentrional. Revista Instituto de Geología, Universidad Nacional Autónoma de México, 1: 1-4.

rOgOV, m.a. (2002) - Stratigraphy of Lower Volgian Deposits of the Russian Plate and Correlation between Volgian and Tithonian Stages. Stratigraphy and Geological Correla-tion, 10: 348-364.

sarti, C. (1993) - Il Kimmeridgiano delle Prealpi Veneto-Tren-tine: Fauna e Biostratigrafia. Memorie del Museo Civico di Storia Naturale di Verona (IP serie), Sezione Scienze della Terra, 5: 9-144.

sChweigert, G., J. krishna, B. pandey & D.B. pathak (1996) - A new approach to the correlation of the Upper Kimmeridgian Beckeri Zone across the Tethyan Sea. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen, 203(3): 345-373.

Verma, h.m. & g.e.g. westermann (1973) - The Tithonian (Jurassic) ammonite fauna and stratigraphy of Sierra de Catorce, San Luis Potosí, Mexico. Bulletin of the American Paleontology, 63(277): 107-320.

VillaseñOr, A.B. (1991) - Aportaciones a la bioestratigrafía, basada en fauna de ammonites, de la sucesión del Jurásico superior (Kimmeridgiano-Tithoniano) del área de Maza-pil, Zacatecas, México. PhD. Thesis, Facultad de Ciencias, Universidad Nacional Autónoma de México: 154 p. (unpublished)

VillaseñOr, a.b. & F. Olóriz (2004) - First occurrence of genus Pseudohimalayites spath (Ammonitina) in Mexico. Sixth International Symposium. Cephalopods-Present & Past. Abstracts: 151.

VillaseñOr, a.b. & F. Olóriz (2009) - Caribbean Lower Tithonian ammonites from central-east Mexico. Geobios, 42: 117-132.

VillaseñOr, a.b. & F. Olóriz (2010) - Biomarkers for a Widespread Tethyan Flooding on Mexican Shelves during the Early Tithonian. In: yusheng, z., s. Jingeng, w. XiaOqiaO, p. yanhOng & w. yOngdOng (eds.), Earth Science Frontiers- Short papers for the 8th International Congress on the Jurassic System, Special Issue, 17: 294-296.

VillaseñOr, a.b., F. Olóriz, gOnzález-arreOla, C. lara, l. & a. de la mOra (1994) - Homotaxy and the Kimme-ridgian-Tithonian Boundary in North-Central Mexico. 4th International Congress on Jurassic Stratigraphy and Geo-logy, Mendoza, Argentina. Abstracts: 46.

VillaseñOr, a.b., F. Olóriz & C. gOnzález-arreOla (2000a) - Recent advances in Upper Jurassic (Kimmerid-gian-Tithonian) ammonite biostratigraphy from North-Central Mexico. Based in new collected ammonite assemblages. GeoResearch Forum, 6: 249-262.

VillaseñOr, a.b., F. Olóriz & C. gOnzález-arreOla (2000b) - Registro del género Hybonoticeras (Ammonoi-dea) en el Jurásico Superior de la Formación Tamán en la región de Mazatepec, Puebla. Geos, 20(3): 300.

VillaseñOr, a.b., F. Olóriz & i. lópez-palOminO (2002) - The finding of the ammonite genus Gregoryceras (Ammo-nitina) from Mexico. In: martire, L. (ed.), 6th International Symposium on the Jurassic System, Palermo, Abstracts: 191.


VillaseñOr, a.b., F. Olóriz & C. gOnzález-arreOla (2003) - First record of the genus Simocosmoceras Spath, 1925, Ammonitina, in Mexico. Biostratigraphic and paleo-biogeographic Interpretation. GFF Geologiska Förenin-gens I Stockholm Förhandlingar, 125: 49-56.

VillaseñOr, a.b., F. Olóriz & i. lópez-palOminO (2004) - Inner whorls of Gregoryceras (Ammonitina, Peltocerati-nae) as the first occurrence of the genus in Mexico. Rivista Italiana di Paleontologia e Stratigrafia, 110(1): 249-254.

VillaseñOr, a.b., C. gOnzález-león, t. lawtOn & m. aberhan (2005) - Upper Jurassic ammonites and bivalves from the Cucurpe Formation, Sonora (Mexico). Revista Mexicana de Ciencias Geológicas, 22(1): 65-87.

VillaseñOr, a.b., F. Olóriz & C. gOnzález-arreOla (2011) - Lower Tithonian microconchiate simoceratins from eastern Mexico: Taxonomy, biostratigraphy, and paleobiogeography. Acta Palaeontologica Polonica, 56(1): 133-158.

zeiss, A. & H.A. Leanza (2008) - Interesting new ammonites from the Upper Jurassic of Argentina and their correlation potential: new possibilities for global correlations at the base of the Upper Tithonian by ammonites, calpionellids and other fossil groups. Newsletters on Stratigraphy, 42 (3): 223-247.

ziegler, B. (1958) - Monographie der Ammonitengattung Glo-chiceras im epikontinentalen Weissjura Mitteleuropas. Palaentographica A., 110(4-6): 93-164.

Accepted September 29th, 2011.

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