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A revision of Amaltheus ebrayi de LORIOL, 1882, type species of the genus Parengonoceras SPATH, 1924

A revision of Amaltheus ebrayi de LORIOL, 1882, type species of the genus Parengonoceras SPATH, 1924
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  1 LeMaupas,F05300,Lazer,France.Email:g.r.e.g.b@wanadoo.fr RevuedePaléobiologie , Genève (juin 2008) 27 (1) : 249-264 I. IntroductIonth a f h assia ai faa D e L oriol   (1882, p. 7 ; pl. 1, g. 1) described  Amaltheus Ebrayi on the basis of ve specimens collected by E bray   in the surroundings of Cosne (Nièvre, Paris Basin, France)(E bray , 1858-64). The precise location of this section isnot nown. An examination of the type material of   AmaltheusEbrayi in the E bray collection (Muséumd’histoire naturelle de Genève, Switzerland), revealed asmall series of ammonites that were collected from Cosnearea.The lithological sequence of Albian strata at Cosne, frombase to top, is as follow (after E bray , 1963) : - Level 6 : sands ;- Level 5 : 10-30 meters of grey to blac ferruginousclay, with green ne-silty calcareous limestone at thebase ;- Level 4 : 30 meters of ferruginous sands, withoutfossils ;- Level 3 : 0,30 meter of gravels with fossils of Middleand Upper Albian age.B reistroffer (1940, p. 64) suggested a basal MiddleAlbian age for the ammonite fauna of Cosne on the basisof co-occurrence in the type area of  Parengonocerasebrayi ( De L oriol , 1882) of “  Douvilleicerasmammilla-tum S chloth . sp. var. monilis (S ow .) B rst ., Pseudoson-neratiaNolletiana L efort sp. (=  Hoplitesinterruptus   “var” ap. D e L oriol   1882 in Mém. Soc. Pal. Suisse, vol.IX, p. 9, pl. X, g. 10 : paratype), SonneratiaDutem- pleana d’O rb . sp. (sec E bray ), ProtohoplitesRaulini-anus d’ o rb . sp. (ibid), Protanisocerasanglicum S path   (=  HelicocerasActeon d’O rb ., non g. : in coll. Sorbonne!)etc.”, while C asey (1978, p. 588) pointed out that all theammonites mentionned by B reistroffer are of the  Dou-villeicerasmammillatum Zone.As pointed out by De   L oriol (1882, p. 4), the ammonitesfrom Cosne in collection were collected from two differ - ent levels : bed 3 and 5 of the Cosne section. The type of preservation of the material in collection provides une - quivocal evidence for its stratigraphical srcin : fossilsfrom bed 5 are slightly crushed, with remains of phos - phatized test, and are cemented by green ne-silty calcar - eous, while fossils from bed 3 are preserved as internalmoulds or with silicied test and are cemented by a yel - lowish calcareous full of small silice gravels.The ammonite fauna studied herein, comes from the bedat base of level 5, “Argiles micacées du Gault” of theCosne section of E bray (1863, p. 210). The following species are described below : Cleoniceras(Cleoniceras)janneli (P arent ), Sonneratiaelegans   C asey , Pseudosonneratianolletiana (L efort ), Paren-gonocerasebrayi ( De L oriol ), Protanisoceras(Torquis-tylus)anglicum (S path ),  Hamites sp. ind.,  Douvilleicerasmammillatumaequinodum (Q uensteDt ),  Douvilleicerasalternans C asey and  Douvilleicerasleightonense C asey . A isi f   Amaltheus Ebrayi    de L oriol , 1882, p spis f h s  Parengonoceras S path , 1924 Jean-Louis LATIL 1 Absa  AmaltheusEbrayi   De L oriol , type species of the genus Parengonoceras S path , is revised on the basis of srcinal material, housed inthe collections of the Muséum d’histoire naturelle de Genève (Switzerland). The associated ammonite fauna is described and gured,including a revision of the enigmatic Sonneratianolletiana ( l efort ). The following species are described below : Cleoniceras(Cleoniceras)janneli (P arent ), Sonneratiaelegans C asey , Pseudosonneratianolletiana (L efort ), Protanisoceras(Torquistylus ) anglicum (S path ),  Hamites sp. ind.,  Douvilleicerasmammillatumaequinodum (Q uensteDt ),  Douvilleicerasalternans C asey and  Douvilleicerasleightonense C asey . This ammonite assemblage is associated with Parengonocerasebrayi ( De L oriol ), and gives arather precise age, Lower Albian  Douvilleicerasmammillatum Superzone, at the top of the Sonneratiachalensis Zone, Cleoniceras (Cleoniceras) oridum Subzone and possibly base of  Otohoplitesauritiformis Zone, Otohoplitesraulinianus Subzone. Kws Albian, Ammonites, biostratigraphy, Nièvre, France, type material. ISSN 0253-6730  250J.-L. LATIL Most of these species are nown elsewhere in Anglo-Paris Basin in Lower Albian  Douvilleicerasmammilla-tum Superzone, at the top of the Sonneratiachalensis Zone, Cleoniceras (Cleoniceras) oridum Subzone andbase of  Otohoplitesauritiformis Zone, Otohoplitesrauli-nianus Subzone ( D estombes , 1979 and o wen , 1988), but  Douvilleicerasleightonense and Sonneratiaelegans   seem to be unnown beyond the top of  Sonneratiacha-lensis Zone. This suggests a top Sonneratiachalensis   Zone, Cleoniceras ( Cleoniceras )  oritum Subzone age. II. conventIonS The following conventions are used to indicate the repos - itories of specimens mentioned in the text : UD, Univer - sity of Dijon, France ; MNHN, Muséum Nationald’Histoire Naturelle, Paris, France ; MHNG, Muséumd’histoire naturelle de Genève, Suisse.All dimensions of specimens are given in millimetres : D= diameter, Wb = whorl breadth, Wh = whorl height, U =umbilical diameter. Figures in parentheses are dimen - sions as a percentage of the diameter at the point of measurement. III. SyStemAtIc PALeontoLogyo Aia Z ittel , 1884Sb Aiia H yatt , 1889Spfail dsaia Z ittel , 1884Fail cliaia W hitehouse , 1926gs Cleoniceras P arona & B onarelli , 1897Sbs Cleoniceras P arona & B onarelli , 1897tp spis :    Ammonitescleon o rbigny , 1850, p. 124, by srcinal designation. disssi : O wen (1988, p. 215) considers the subge - nus C  . ( Cleonella ) D estombes , 1970, p. 2063 (type spe - cies : Cleonicerasdimorphum   c asey , 1966, p. 568 bysrcinal designation) as a subjective synonym of the sub - genus C  . ( Cleoniceras ) while w right (1996, p. 96) con - siders it as a synonym of the subgenus C  . (  Anacleoniceras )   M irzoev , 1969, p. 38 (type species :  Anacleonicerascaseyi by srcinal designation), and suggests that they areprobably microconchs of  C  . ( Cleoniceras ). The phylogeny of the Cleoniceratidae is not well nownand has to be revised. Authors generally placed this fam - ily in Hoplitoidea ( c asey , 1960 ; s aveliev , 1973 &1992 ; o wen , 1988). Both o wen (1988, p. 212) and w right (1996, p. 93) consider that Cleoniceratidae hasan srcin in Puzosiinae rather than in Beudanticeratinaeand that Beudanticeratinae is the presumed source of Hoplitids, but o wen placed the Cleoniceratidae in Hop - litoidea and w right in Desmoceratoidea. I arbitrarilyfollow the treatise treatment for this family. Cleoniceras (Cleoniceras) janneli  (P arent , 1894) Pl. I, fgs 1, 2 ; 5, 6 1894.  HoplitesJanneli P arent , p. 266-70, pl. 6, gs 2 only. 1966. Cleoniceras(Cleoniceras)janneli (P arent ).- C asey , p. 560, pl. 92, g. 2 ; pl. 95, g. 7 ; text-g. 213. 1979. Cleoniceras(Cleonella)ornatum D estombes , p. 94, pl. 4-16, g. 6. 1988. Cleoniceras(Cleoniceras)janneli (P arent ).- O wen , p.216. maial : A slightly crushed fragment, at about 45 mmin diameter, preserved as internal mould, MHNG.035801(Pl. I, gs 5, 6) ; and a juvenile compressed specimen,MHNG.035802 (Pl. I, gs 1, 2) ; both from e bray   collection. dsipi : Subelliptical to subrectangular highwhorled section, ans attened, maximum of width atinner third of an, narrow arched venter. Umbilicusabout one quarter of diameter ; with low, steep, rimless,umbilical slope. Rather strong, coarse umbilical swelling.Strongly sigmoidal, sharply rounded ribs, arising frombullae in group of two-three, some ribs becoming interca - latory and arising at about inner third of an. Ribsstrongly broaden on outer third of ans and stronglyprojected forward in chevron on ventral area. Suture unknown. disssi : MHNG.035801 (Pl. I, gs 5, 6) is very closeto the ammonite gured by D estombes (1979, pl. 4-16, g. 6) as Cleoniceras(Cleonella)ornatum D estombes , and I follow O wen (1988, p. 216) interpretation of  Cle-onicerasjanneli (P arent ). Cleoniceras oridum C asey , 1961 (p. 599, pl. 84, gs 6-7) has a subacute venter andsmooth siphonal area in juvenile stages, less prominentbullae and weaer ornament at mid an. Cleonicerasquercifolium (d’O rbigny ) shows a smooth ventral area. o : The species is nown from the  Douvil-leicerasmammillatum Zone, Cleoniceras(Cleoniceras)  oridum and Otohoplitesraulinianus Subzones in Eng - land ; Cleoniceras (Cleoniceras) oridum Subzone of Perchois-Ouest quarry (Aube), France ; from the con - densed Lower Albian of Machéroménil (Ardennes),France ; and from the base of bed 5 of Cosne section(Nièvre), France. Spfail Hpliia H. d ouvillé , 1890Fail Hpliia H. d ouvillé , 1890Sbfail Saiia d estombes , J uignet &r ioult , 1973gs Sonneratia B ayle , 1878(=  Eosonneratia S aveliev , 1973 ; Globosonneratia  S aveliev , 1973)tp spis :    Ammonitesdutempleanus d’O rbigny , 1850, p. 123, by monotypy.  A revision of  AmaltheusEbrayi De L oriol , 1882251 Sonneratia elegans c asey , 1964 Pl. I, fgs 7, 8 1964. Sonneratiaelegans C asey p. 528, pl. 88, gs 6, 7. 1988. Sonneratia(Sonneratia)elegans C asey .- O wen , p. 220, gs 45a, b. maial : A single, slightly crushed, specimen preservedas internal mould MHNG.035805 (Pl. I , gs 7, 8), E bray   collection.D : 37 – Wb : 19 (.51) – Wh : 16 (.43) – U : 7,5 (.20) dsipi : Flans convex, maximum of width atumbilical bullae, arched venter. Narrow umbilicus withsteep, rimless, umbilical slope. Rather strong, elongatedbullae. Straight, radial, sharply rounded ribs, arising frombullae at rst almost regularly in group of three, and thenpredominately bifurcating, the third rib becoming inter - calatory and arising at about inner third of an. Ribsbroaden on ventral area, showing a tendency to be pro -  jected forward and to become effaced over the siphonalline. Suture unnown. disssi : Our specimen is very closed to the one g - ured by O wen (1988, g. 45) and may represent a transi - tional form between the genera Sonneratia B ayle and Pseudosonneratia S path , by its tendency for the ribbingto become effaced over the siphonal line and to eep itsforward projection on the ventral area. o : The species is nown from the  Douvilleicerasmammillatum Zone, Sonneratiakitchini   Subzone, condensed Cleoniceras (Cleoniceras) oridum  - Otohoplitesraulinianus Subzones, in England ; andfrom the base of bed 5 of Cosne section (Nièvre),France. gs  Pseudosonneratia S path , 1925 tp spis :   Pseudosonneratiatypica S path , 1925, p. 76, by srcinal designation.  Pseudosonneratia nolletiana (L efort , 1894) Pl. I, fgs 3, 4 1882.  Hoplitesinterruptus B ruguiere .- De   L oriol , p. 9, pl. 10, gs 10. 1894.  Ammonites(Hoplites)Nolletianus L efort , p. 12, gs 1, 2.1940. PseudosonneratiaNolletiana L efort sp.- B reistrof - fer , p. 64.1947. PseudosonneratiaNolletiana L efort 1894 sp.- B reis - troffer , p. 69. tp aial : The type material is based on two syn - types : the specimen described by De l oriol (1882, p. 9, pl. 10, g. 10) as  Hoplitesinterruptus ( b ruguière ), anda specimen described and gured by l efort (1894, p. 12, gs 1, 2) from Saint-Satur (Nièvre). I was unable tolocate the specimen described and poorly gured by l efort . The specimen gured by De   L oriol (1882, pl. 10, g. 10)is herein designated as lectotype, This is a fragment of body chamber, preserved as internal mould,MHNG.035486, E bray collection from the base of bed 5of Cosne section (Nièvre), France. This is a piece of thespecimen gured by De   L oriol   and herein regured Pl.I, gs 3, 4.D : 70 – Wb : 22 (.31) – Wh : 36 (.51) – U : 13 (.19) (after De   L oriol , 1882, p. 9). dsipi : Juveline stages are nown from a cast of internal whorls, and are characterized by wide, stronglysigmoidal ribs, which are strongly projected forward onventral area. At this stage of growth, at about 20 mmdiameter, there is some resemblance with adult ribbingstyle of  Cleoniceras(Cleoniceras)janneli (P arent ), specimen MHNG.035801 (Pl. I, gs 5, 6).Adult shows feebly convex ans, maximum of width atabout inner third of an, rather narrow, arched venter.Narrow umbilicus with very low, steep, umbilical slope.Feeble, coarse, elongated umbilical bullae. Strongly sig - moidal, coarse, rounded ribs, that show a tendency to beeffaced on the inner half of an, arise from umbilicalbullae in group of two or three, intercalatories may occur.Ribs broaden on ventral area, showing a tendency to beprojected forward and to become effaced over the sipho - nal line. Suture unnown. disssi : This species remains enigmatic, and itsgeneric attribution is doubtful. There is some resemblance with Cleoniceras(Cleoniceras)janneli   (P arent ) fromwhich Pseudosonneratianolletiana (L efort ) differs bywider ventral area, higher costal density and a tendencyfor ribbing to be effaced on inner third of ans and ven - tral area. o : Below the clays of Saint-Satur (Nièvre,France), and the base of bed 5 of Cosne section (Nièvre),France,  Douvilleicerasmammillatum Zone, Sonneratiachalensis Zone, Cleoniceras ( Cleoniceras )  oritum Subzone. Spfail Plhlliaia d ouvillé , 1890Fail eaia H yatt , 1900(= Kiaia H yatt , 1903 ; Neolobitinae L uppov & m akhailov , i L uppov & d rushchits   Eds, 1958) gs  Parengonoceras S path , 1924tp spis :    AmaltheusEbrayi   De L oriol , 1882, p. 7, by srcinal designation by S path , 1924, p. 508. gi haas : Discoidal involute Engonocerati - dae. Early whorls with subtriangular section, at sidesconverging to narrow, at or slightly grooved venter ;indistinct exuous ribs. Adult stages with subtriangular tosuboval section, narrow to rather broad generally atventer, ornament with striae and/or feeble ribs, 0-4 tuber - cles on the ans. Suture as in Knemiceras B öhm , 1898 but with frilled bid saddles (Fig. 2).  252J.-L. LATIL  Parengonoceras ebrayi    ( de   L oriol , 1882) Figs 1-6 ; Pl. III, fgs 1-4 ? 1853.  AmmonitesIcaunensis , C otteau , p. 330-31.1882. AmaltheusEbrayi   De   L oriol , p. 7, pl. 1.1924. Parengonocerasebrayi ( De   L orio l).- S path , p.508.1940. ParengonocerasEbrayi P. De   L oriol .- B reis - troffer , p. 62.1952. Parengonocerasebrayi De L oriol .- B asse , 1952, p. 658, pl. 23, g. 8 ; 1978. Parengonocerasebrayi ( De   L oriol ).- C asey , p. 587 (pars), text-g. 220, 221h. non 1978. Parengonocerasebrayi ( De L oriol ).- C asey , p. 587 (pars), pl. 100, gs 9-11, text-g. 221e-g. 1979. Parengonoceras aff. ebrayi ( De   L oriol ).- D estombes , p. 113, pl. 4-20, gs 1, 2. non 2002. Parengonocerasebrayi ( De L oriol , 1882).- R ob - ert , p. 100, pl. 1, gs 1-4, pl. 2, gs 1, 2. non 2004. Parengonocerasebrayi ( De   L oriol ).- R obert & B ulot , pl. 2, g. 1. tp aial : The species was described on the basisof ve syntypes. R obert (2002, p. 100) selected thespecimen gured by De   L oriol (1882, pl. 1 : MHNG.035492, E bray collection) as lectotype (Pl. III,g. 1-4). The srcinal illustration, idealized, is reproducedherein (Fig. 1). Consequently, there are four paralecto - types among the ve additional specimens we found inthe collections. maial : Five additional slightly crushed, adult ammo - nites (diameter comprises between 240 and 320 mm),preserved partly as internal mould, partly with phos - phatized test : MHNG.035492a, MHNG.035492b,MHNG.035492c, MHNG.035807, MHNG.035808 : allfrom E bray collection.MHNG.035492 : D : 250 – Wb : 60 (.24) – Wh : 120 (.48) – U : 32 (.13)MHNG.035492 : D : 200 – Wb : 48 (.24) – Wh : 110 (.55) – U : 15 (.08)MHNG.035492a : D : 240 – Wb : 55 (.23) – Wh : 115 (.48) – U : 35 (.15) (Fig. 5) dsipi : Juvenile to 100 mm diameter, involute,with deep, steep umbilical wall and well-rounded margin.High-whorled, compressed, subtriangular section, maxi - mum of width at about inner third of an. Gently convexans, attened venter area, spirally elongated, ventro-lateral clavi, that alternate on opposite sides. At this stage,ornament on ans is reduced to sigmoidal striations,projected bacward on inner third of an, forward onmiddle part and bacward again on outer part of an.These striations are conspicuous when test is preserved,indistinct on internal mould.At about 120-150 mm diameter, apparition of roundedinner lateral bullae at about inner fth of an.At about 150-180 mm diameter, apparition of coarse,rounded ribs, alternating one primary rising at umbilicalwall, one intercalatory rising a about mid an. Appari - tion of ribbing is correlated with apparition of mid-lateralbullae, twice as numerous as inner lateral ones, and outerlateral rounded bullae, twice as numerous as mid-lateralones.At about 160-200 mm diameter, ventrolateral clavi disap - pear and the whorl section becomes subrectangular, withslightly convex ans and broadly rounded ventral area.At this stage, mid-lateral bullae are as numerous as innerlateral ones, outer lateral bullae remaining twice as nume - rous as inner lateral and mid-lateral ones.On last visible ontogenetic stages, the test is mared withconspicuous, coarse, dense and sigmoidal riblets, tuber - culation is strongly attenuated, but peri-umbilical bullaetend to persist.Coiling tends to be subscaphitoid towards the aperture.The largest specimen (MHNG.035808, Fig. 4), about 320mm diameter, represented by a phragmocone and begin - ning of body chamber, is feebly tuberculated and bears 2-3 intercalatory ribs for a primary.Ontogenetic changes of ornamentation are somewhatvariable. On MHNG.035807 (Fig. 6, 250 mm diameter),apparition of inner-lateral, mid-lateral and outer-lateralbullae is simultaneous, outer-lateral ones persist towardsaperture and are fourth as numerous as mid-lateral ones.MHNG.035492c (Fig. 3) represents an extreme morpho - logy with compressed section and characterized by occa - sional feeble lateral swellings, lac of outer-lateral bullae,and early disparition of ventro-lateral clavi. disssi : According with C asey (1978, p. 588), Parengonocerasebrayi ( De L oriol ) is possibly conspe - cic with  AmmonitesIcaunensis C otteau , (1853, p. 330), from the Albian of Ravennes, near Gurgy (Yonne,France), but srcinal material has not been gured andwas not found in the collections.As pointed out by C asey , the d’O rbigny collection, inthe Muséum d’Histoire Naturelle de Paris, contains a spe - cimen from the Albian of Géraudot, Aube, France, label - led “  Ammonitesicaunensis ” C otteau (d’O rbigny   collection n°5801, now MNHN.B10490). This specimenis a badly preserved, distorted fragment of phragmoconethat shows a subtriangular, compressed section, narrow,attened venter, and no visible ornament. This ammoniteprobably belongs to Parengonocerasebrayi ( De  L oriol ). Material gured by C asey (1978, pl. 100, gs 9-11, text-g. 221e-g) from Cleoniceras (Cleoniceras) oridum and Otohoplitesraulinianus Subzones of England, are cha - racterized by the occurrence of conspicuous costae, peri-umbilical and mid-lateral bullae on juveniles, suchornament was not observed in the type material of  Paren-gonocerasebrayi ( De L oriol ). As pointed out by C asey , this material shows strong afnities with Algerian mate - rial gured by D ubourDieu (1953) and could belong to Parengonocerasmahmoudi (D ubourDieu , 1953, p. 19, pl. 1, g. 18-24 ; pl. 2, g. 1-5).The two specimens gured by D estombes (1979, pl. 4- 20, gs 1, 2) from the Lower Albian of Perchois-Ouest  A revision of  AmaltheusEbrayi De L oriol , 1882253 Quarry (Aube, France) (U.D..9.65.1 and UD.7.70.8) arevery close to Parengonocerasebrayi (de L oriol ), anddiffers only by an apparent earlier development of orna - ment on an. Moreover, at about 150 mm diameter, ven - tral area is well-rounded. Apparent differences in widthof ventral area is probably due to the preservation of typematerial as slightly crushed fossils.Peruvian specimens described and gured by R obert   (2002, p. 100, pl. 1, gs 1-4, pl. 2, gs 1, 2) and R obert   & B ulot (2004,  pl. 2, g. 1) as Parengonocerasebrayi  ( De   L oriol ), differs in many respects from P.ebrayi ( De  L oriol ). Peruvian specimens have Wh/D that comprisesbetween 0,37 and 0,45 (0,48-0,55 for P.ebrayi [ De  L oriol ]), much stronger ornament on an, appearing at Fig. 1 : Parengonocerasebrayi (de L oriol ) : the srcinal guration of   Amaltheusebrayi   De L oriol , 1882, pl. 1. MHNG.035492c, lec - totype, bed 5 of Cosne section (Nièvre), France (x 0,62).Fig. 2 : The srcinal guration of the suture of the lectotype of   Amaltheusebrayi   De L oriol , p. 7, pl. 1.
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