34 J.E. Caracuel et al. / Geobios 39 (2006) 25–42 Fig. 4. Lower <strong>Jurassic</strong> ammonites from Sierra Espuña. All <strong>the</strong> specimens are figured at natural size except for B (× 2). A. L. villae Meneghini, MI.121S.1, Middle Domerian, Algovianum Zone, Malvariche section 121 m. B. F. fieldingii (Reynes), MI121S.2, Middle Domerian, Malvariche section 121 m. C. Fuciniceras cornacaldense (Taush) MI.121S.3, Malvariche section 121 m, D. Reynesoceras ragazzonii (Hauer), MI.121S.4, Middle Domerian, Algovianum Zone, Malvariche 121.5 m. E. A. algovianum (Oppel), MI.121S.5, Algovianum Zone, Malvariche section 121.5 m. F. Arieticeras disputabile (Fucini), PM.60.10,
toge<strong>the</strong>r with inner molds, sometimes truncated, corroded, occasionally fragmented, <strong>and</strong> usually imbricate. Both inner molds <strong>and</strong> shells can occasionally be covered by Fe–Mn crusts. The assemblage is dominated by Phylloceratina [Phylloceras trifoliatum Neumayr, Holcophylloceras zignodianum (Orbigny), Calliphylloceras disputabile (Zittel) <strong>and</strong> Ptychophylloceras flabellatum (Neumayr)], which reach <strong>the</strong> 60%. Macrocephallitinae as Macrocephalites gracilis (Spath) (Fig. 5E), <strong>and</strong> Macrocephalites? sp. along with Haploceratidae [Lissoceratoides jullieni (Douvillé)] are also abundant. O<strong>the</strong>r groups as Hecticoceratinae (Hecticoceras (Chanasia) bannense Elmi (Fig. 5C), He. (Ch.) sp. <strong>and</strong> Jeanneticeras? sp.), Reineckeiidae [Rehmannia (Re.) freii (Jeannet) sensu Cariou (1980) (Fig. 5D), Collotia oxyptycha (Neumayr)], Perisphinctidae (Ch<strong>of</strong>fatia waageni (Teisseyre), Grossouvria sp., Parapatoceratinae, (Parapatoceras tuberculatum (Baugier <strong>and</strong> Sauzé), Pa. sp.) <strong>and</strong> Oppeliinae (Oxycerites sp.) are also common. Middle <strong>Jurassic</strong> ammonites are scarcer in Prat Mayor section. Seyfried (1978) reported Spiroceras sp. <strong>and</strong> Nannolytoceras sp. from <strong>the</strong> Upper Bajocian, <strong>and</strong> we collected only two specimens (Hecticoceras (Ch.) sp. <strong>and</strong> Grossouvria sp., 214 m) which probably represent <strong>the</strong> Lower Callovian (Gracilis Zone). Oxfordian ammonite assemblages were recorded in 7 m <strong>of</strong> succession in <strong>the</strong> Prat Mayor section (237.5–244.5 m in Fig. 2) at <strong>the</strong> top <strong>of</strong> nodular-limestone levels, sometimes brecciated. As usual in ammonitico rosso facies, ammonites are preserved as inner moulds with complete phragmocone <strong>and</strong> incomplete body chambers. Sutures are poorly or not at all preserved, indicative <strong>of</strong> relatively deep deposition (Fernández- López, 2000). No significant taphonomic size bias was noted, although <strong>the</strong> smaller ammonites are frequently lying oblique (even vertical) with respect to <strong>the</strong> stratification, especially at <strong>the</strong> top <strong>of</strong> <strong>the</strong> strata. As a whole, Phylloceratina reach <strong>the</strong> 37.5% (mainly Calliphylloceras <strong>and</strong> secondarily Sowerbyceras) <strong>of</strong> <strong>the</strong> assemblage. The Middle Oxfordian, Transversarium Zone, was registered in a single horizon with <strong>the</strong> record <strong>of</strong> Calliphylloceras silesiacum (Oppel), Ca. manfredi (Oppel), Sowerbyceras tortisulcatum (d’Orbigny), Euaspidoceras (Eu.) gr.oegir (Oppel), Taramelliceras (Ta.) cf. callicerum (Oppel), Perisphinctes (Arisphinctes) cf. helenae De Riaz <strong>and</strong> Pe. (Dichotomosphinctes) sp., among o<strong>the</strong>rs. Some 2 m upward, <strong>the</strong>re are three horizons with scarce but significant fauna <strong>of</strong> J.E. Caracuel et al. / Geobios 39 (2006) 25–42 Pe. (Dichotomoceras) bifurcatoides Enay (Fig. 6A), Pe.(Di.) cf. bifurcatus (Quenstedt), Pe.(Dichotomosphinctes) cf. elisabethae (De Riaz) <strong>and</strong> a specimen <strong>of</strong> Pe. (Dichotomosphinctes)aff.ultimus, with atypical abundance <strong>of</strong> trifurcate ribs in <strong>the</strong> body chamber, toge<strong>the</strong>r with Calliphylloceras <strong>and</strong> Sowerbyceras, which characterize <strong>the</strong> Bifurcatus Zone. The Upper Oxfordian, Bimammatum Zone (or still <strong>the</strong> uppermost Bifurcatus Zone) was unsurely recorded in a horizon with Passendorferia (Passendorferia) cf. teresiformis (Brochwich- Lewinski), Pa. (Pa.) sp. <strong>and</strong> Trimarginites gr. trimarginatus Oppel, just 50 cm below <strong>the</strong> first record <strong>of</strong> Subnebrodites in <strong>the</strong> Planula Zone. Upwardly, four ammonite-bearing horizons, spaced within a thickness <strong>of</strong> 2.5 m, enabled <strong>the</strong> recognition <strong>of</strong> <strong>the</strong> Planula Zone by <strong>the</strong> record <strong>of</strong> Subnebrodites cf. schröederi (Wegele), Su. cf. minutum (Hehl) sensu Zieten (1830–1834), Passendorferia (Pa.)aff.uptonoides (Fig. 6B), Pa. (Pa.) sp., Physodoceras altenense (d’Orbigny), Orthosphinctes sp. <strong>and</strong> abundant Phylloceratina (mainly Sowerbyceras). Kimmeridgian ammonite assemblages in <strong>the</strong> Prat Mayor section were registered from 246.4 to 260 m (Figs. 2 <strong>and</strong> 6). As in <strong>the</strong> underlying Oxfordian, <strong>the</strong> lith<strong>of</strong>acies is composed by nodular limestones with thicker <strong>and</strong> more brecciated levels. The Kimmeridgian succession has less, <strong>and</strong> more widely spaced, ammonite-bearing horizons. Never<strong>the</strong>less, <strong>the</strong> ammonite mode <strong>of</strong> preservation is similar to that <strong>of</strong> <strong>the</strong> Oxfordian, although, due to <strong>the</strong> higher sedimentation rate, some specimens have lost <strong>the</strong> inner whorls (or have become flattened due to <strong>the</strong> absence <strong>of</strong> sediment infill during early diagenesis). The amount <strong>of</strong> Phylloceratina is higher, reaching <strong>the</strong> 50%, mainly by <strong>the</strong> contribution <strong>of</strong> <strong>the</strong> eurythopic genus Sowerbyceras. Almost 2 m above <strong>the</strong> last record <strong>of</strong> <strong>the</strong> Planula Zone, <strong>the</strong>re is a horizon attributed to <strong>the</strong> lowermost Kimmeridgian (Platynota Zone?) based on <strong>the</strong> record <strong>of</strong> Sutneria gr. galar (Oppel), Streblites tenuilobatus (Oppel), Glochiceras (Lingulaticeras)gr.nudatum (Oppel)-lingulatum (Quenstedt), Gl. (Li.) sp., Aspidoceras sp., Orthosphinctes (Orthosphinctes) polygyratus (Reinecke) sensu Schairer morph. colubrinus Olóriz (Fig. 6F), Or.(Or.) sp, Or.(Lithacosphinctes) sp. <strong>and</strong> abundant Phylloceratina [So. silenum (Fontannes) as well as, secondarily, Ly. orsinii (Gemmelaro) <strong>and</strong> Ho. mediterraneum (Neumayr)]. Above appear Nebrodites (Nebrodites)gr. hospes (Neumayr) (Fig. 6C), Ne.(Ne.) sp., Presimoceras sp., Middle Domerian, Algovianum Zone, Prat Mayor section 60 m. G. Emaciaticeras lottii Fucini, TC.100A.3, Upper Domerian, Emaciatum Zone, Tres Carrascas section 1 m. H. E. levidorsatum Fucini, TC.40.1 Upper Domerian, Emaciatum Zone, Tres Carrascas section 0.4 m. I. Emaciaticeras timaei (Gemmellaro), TC.100A.2, Upper Domerian, Emaciatum Zone, Tres Carrascas section 1 m. J. H. bifrons (Brugière), MC.180.1, Middle Toarcian, Bifrons Zone, Morrón Chico section 1.8 m. Fig. 4. Ammonites du Jurassique inférieur de la Sierra Espuña. Tous les spécimens sont représentés à gr<strong>and</strong>eur naturelle sauf B (× 2). A. L. villae Meneghini, MI.121S.1, Domérien moyen, Zone à Algovianum, section de Malvariche 121 m. B. F. fieldingii (Reynes), MI121S.2, Domérien moyen, section de Malvariche 121 m. C. Fuciniceras cornacaldense (Taush) MI.121S.3, section de Malvariche 121 m. D. Reynesoceras ragazzonii (Hauer), MI.121S.4, Domérien moyen, Zone à Algovianum, section de Malvariche 121,5 m. E. A. algovianum (Oppel), MI.121S.5, Zone à Algovianum, section de Malvariche 121,5 m. F. Arieticeras disputabile (Fucini), PM.60.10, Domérien moyen, Zone à Algovianum, section de Prat Mayor 60 m. G. Emaciaticeras lottii Fucini, TC.100A.3, Domérien supérieur, Zone à Emaciatum, section de Tres Carrascas 1 m. H. E. levidorsatum Fucini, TC.40.1, Domérien supérieur, Zone à Emaciatum, section de Tres Carrascas 0,4 m. I. Emaciaticeras timaei (Gemmellaro), TC.100A.2, Domérien supérieur, Zone à Emaciatum, section de Tres Carrascas 1 m. J. H. bifrons (Brugière), MC.180.1, Toarcien moyen, Zone à Bifrons, section de Morrón Chico 1,8 m. 35
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