Transcript

F R A G M E N T A M I N E R A L O G I C A et P A L A E O N T O L O G I C A 12. 1985 p. 19-26

A Bathonian (Middle Jurassic) ammonite fauniila from Monte Kumeta (Western Sicily)

By

A . G A L Á C Z (Received November 30, 1984)

A b s t r a c t : A s m a l l fauna of Bathonian ammoni tes is desc r ibed f r o m the condensed Middle Ju ras s i c l imes tone of Monte K u m e t a . Despite the l i m i t e d specimen number , a r e l a t i v e l y d ive r se associat ion i s represented, suggesting Lower and Midd le Bathonian h o r i z o n s . The p rese rva t ion and the age of the faunal elements ind ica te condensation and faunal m i x i n g . The sys temat ic pa r t gives the desc r ip t ions of 8 species represen t ing 7 ammoni te f a m i l i e s .

I N T R O D U C T I O N

I n 1983 f ield w o r k was c a r r i e d out to obta in s t ra t ig raph ie data on the Ju ras s i c o f Wes te rn S i c i l y . L o w e r and Midd le Jurass ic faunas w e r e col lec ted i n s e v e r a l l o c a l i t i e s , wh ich i n some cases made i t possible to re f ine the f o r m e r s t r a t i g r a p h i e knowledge.

One of the v i s i t ed l o c a l i t i e s was Monte Kumeta , f r o m where the Jurass ic sequence i s b r i e f l y ment ioned i n numerous genera l desc r ip t ions , however deta i led i n f o r m a t i o n i s l a c k i n g . Thus the r e ­sul ts of studies on a s m a l l Bathonian fauna may poss ib ly be o f some general i n t e r e s t .

A c k n o w l e d g e m e n t s : These studies w e r e c a r r i e d out th rough a j o i n t r e s e a r c h - p r o j e c t e s ­tab l i shed between the Universitá d i Napol i and the Eötvös Loránd Tudományegyetem, Budapest . In ' the f r a m e w o r k of th i s p r o j e c t f ie ld w o r k i n S i c i l y was organized by P r o f . Bruno D ' ARGENIO ( U n i ­v e r s i t y of Naples) and P r o f . Raimondo C A T A L A N O (Unive r s i ty of P a l e r m o ) . Guidance i n the f ie ld was p r o v i d e d by R. C A T A L A N O and Leonardo G A T T O , to whom I am p a r t i c u l a r l y indebted .

L O C A L I T Y

Monte Kumeta i s a h igh mount sur rounded ma in ly by T e r t i a r y sediments i n the southern m a r ­g in o f the P a l e r m o Moun ta ins . The general geology of the s i te has been descr ibed b r i e f l y by C A ­T A L A N O & D* ARGENIO (1981, 1982). S i m i l a r l y to other i so la ted mounts i n Wes te rn S i c i l y ( e . g . Monte I n i c i , Rocca B u s a m b r a , e t c . ) , the t h i c k T r i a s s i c - L o w e r Jurass ic p l a t f o r m carbonates are capped by t h i n , usua l ly cons iderab ly condensed Middle Jurass ic and pelagic Upper Jurass ic l i m e ­s tones .

The references to M i d d l e Jurass ic ammoni t e s f rom M . Kumeta are given by W E N D T (1963, p p . 84-85) , who recorded a L o w e r to M i d d l e Bajocian condensed fauna f r o m a loose b l o c k . Subse-

quently W E N D T (1965, p . 29Q}.published a l i s t o f a condensed Upper Aalenian to L o w e r Ca l lov i an ammoni te fauna, w i t h some elements suggesting the presence of the Midd le Ba thonian . L a t e r WENDT (1969, f i g . 3) recorded " m a s s i v e , bedded, nodular l imes tone" , i . e . continuous sedimenta­t i o n f r o m the Midd le Bajocian up to the uppermos t J u r a s s i c .

F i g . 1 , S i m p l i f i e d geological map of the l o c a l i t y (as te r i sk) on Monte Kumeta , S i c i l y . 1 : slope debr i s ; 2: Midd le Miocene c l a y - m a r l s ; 3r Lower Miocene carbonates; 4: Miocene - Oligocène s i l t s tone (Numidian F l y s c h ) ; 5: Midd le Eocene - Upper Cretaceous white and p i n k pelagic l imes tone (Scaglia); 6: Lower Cretaceous - Upper Ju rass ic pelagic l imes tone (La t t imusa ) ; 7; Upper and M i d d l e Jurass ic r e d l imes tone (Rosso A m m o n i t i c o ) ; 8: L o w e r Ju rass ic - Upper T r i a s s i c p l a t f o r m carbonates ; 9: faul ts ;

10: o v e r t h r u s t

In 1983 around the top o f Monte Kumeta s e v e r a l s m a l l q u a r r i e s worked the red M i d d l e Jurass ic l imes tones , g i v i n g good oppor tun i t ies of s tudy. Numerous faunules of d i f fe ren t Jurass ic hor izons were co l l ec t ed , one of wh ich i s t r ea ted h e r e . T h e l o c a l i t y ( F i g . 1) i s near to the eas te rnmos t edge of the h i l l - t o p , where the u n d e r l y i n g p l a t f o r m carbonates f o r m mos t o f the surface exposures . The Bathonian fauna was found i n the n o r t h e r n side o f a W - E running gorge of c . 30 m w i d t h . The m o r ­phology suggests the presence of a wide f i s su re f i l l e d w i t h megabrecc ia of d i f ferent Ju ras s i c b locks . Other p o s s i b i l i t y is a l oca l depress ion on top o f the unde r ly ing mass ive carbonates, whe re the Midd le Ju rass ic condensation h o r i z o n was p r e s e r v e d as an e ros iona l r e m n a n t . F u r t h e r f i e l d studies would be necessary to find out the actual s i t u a t i o n .

P R E S E R V A T I O N OF T H E F A U N A

The co l l ec t ed ammoni tes are incomple te but p a r t i a l l y w e l l - p r e s e r v e d spec imens . A H are e-roded on one side, whi le the o ther side c l e a r l y shows the deta i ls o f the scu lp ture , being retained the r e c r y s t a l l i z e d s h e l l . The body chambers a re usua l ly mi s s ing , and the once f ragmented p h r a g -mocones have been covered by th in fer romanganous c r u s t o r f i l m , and the subsequent e r o s i o n has w o r n out these p a r t i a l l y broken spec imens . On the other hand, the i n f i l l i n g m a t e r i a l and the m a t r i x of the fos s i l s are p r a c t i c a l l y the same r e d m i c r i t i c l imes tone , and th i s fact indicates ins ign i f ican t t r a n s p o r t . The presence of L o w e r and Middle Bathonian elements i n the fauna (see below) suggests t e m p o r a l condensation, so a l l fac tors indicate c o m p l e x deposi t ional h i s t o r y . Without deta i led sed i -mento log ica l analysis one can conclude r e w o r k i n g and associated faunal m i x i n g i n the M i d d l e Bathonian .

AGE OF T H E F A U N A

The l i m i t e d ammoni te fauna cons is t s o f the f o l l o w i n g f o r m s :

Phy l loce ra s t r i f o l i a t u m N e u m . ? C a l l i p h y l l o c e r a s sp . inde t .

P tychophyl loceras f l abe l l a tum (Neum. ) P rohec t i coce ras haugi (Pop . -Hä tz . ) L i s soce ra s (L i s soceras ) f e r r i f e x ( Z i t t . ) L i s soce ra s ( L . ) sp . inde t . Cadomites (Cadomites) sp. i n d e t . Cadomites (Polypiec t i tes ) cornutus Kopik Choffatia (Subgrossouvria) u r i n i a c e n s i s ( L i s s . ) Morphoceras m u l t i f o r m e A r k e l l Rug i fe r i t e s (Rugifer i tes) n . s p . af f . R . ( R . ) po lyp leurus ( B u c k m . ) Rug i f e r i t e s ( R . ) sp . inde t .

The s t r a t i g raph ie a l l y undiagnostic phy l loce ra t id s are associated to some impor t an t e l emen t s . M o r p h o ­ ceras m u l t i f o r m e and Cadomites ( P . ) cornutus undoubtedly indicate the L o w e r Bathonian Zigzag Zone whi le P rohec t i coce ras haugi . Rug i f e r i t e s spp. and Choffat ia (S.) u r in i acens i s suggest the Midd le Bathonian Subcontractus Zone. The presence of e lements of two hor izons w i t h i n a s ingle faunula can be due to faunal m i x i n g i n the Midd le Bathonian .

Midd le Bathonian i s a ho r i zon o f widespread occur rence i n Wes te rn S i c i l y . Condensed or mixed faunas of s i m i l a r age were r ecorded e . g . f r o m Monte E r i c e and Monte Bonifato by W E N D T (1963), and f r o m Monte I n i c i by A R K E L L (1954).

SYSTEMATIC DESCRIPTIONS

O r d e r A M M O N O I D E A Z i t t e l , 1884 Suborder P H Y L L O C E R A T I N A A r k e l l , 1950 Superfamily P h y 11 oc e r a t ac e a e Z i t t e l , 1884 F a m i l y Phy l loce ra t idae Z i t t e l , 1884 Genus Phy l loce ra s Suess, 1865

Phy l loce ra s t r i f o l i a t u m N E U M A Y R , 1871 (Plate I , F i g s 3-4)

1 8 7 1 . P h y l l o c e r a s t r i f o l i a t u m nov . sp . — N E U M A Y R , p . 309, p l . X I I , f igs 2 - 3 . 1980. P h y l l o c e r a s t r i f o l i a t u m N E U M A Y R , 1871 — G A L Á C Z , p . 28, p l . I , figs 1-3, t e x t - f i g s 11 -12 .

(cum s y n . )

D e s c r i p t i o n : T h e r e a re two specimens i n the co l lec ted m a t e r i a l , the b igger one i s of c-a. 5 .5 c m i n d iamete r , but w o r n ob l ique ly . T h i s i s a who l ly septate, incomple te f o r m w i t h some rema ins of the r e c r y s t a l l i z e d s h e l l . The s m a l l e r specimen i s s i m i l a r l y p re se rved , i t s d imensions are at 23 m m d iamete r : 14 (61%); 8.5 (37%); 0 .6 (2 .6%) . The u m b i l i c u s i s e x t r e m e l y n a r r o w , the w h o r l - s e c t i o n is e l l i p t i c a l , w i t h oblique u m b i l i c a l slope, convex flanks and arched ven te r . The specimens are smooth, wi thout t r aces of s cu lp tu re . Suture l ines cannot be seen c l e a r l y . R e m a r k s : The poss ib le cause why th i s species is r a r e l y mentioned was discussed e lsewhere (GA­LÁCZ 1980, p . 2 8 ) . The occur rence i n th i s fauna i s an argument fo r r e g a r d i n g th is species as a common element i n Medi t e r ranean Bajocian-Bathonian faunas. In Hungary P . t r i f o l i a t u m o c c u r r e d only i n the Upper Bajocian , but e lsewhere i t was r eco rded f r o m the Bathonian t o o .

Genus P tychophyl loceras Spath, 1927

Ptychophyl loceras f l abe l l a tum ( N E U M A Y R , 1871) (Plate I , F igs 1-2)

1871 . Phy l loce ra s f l abe l l a tum nov . sp . — N E U M A Y R , p . 323, p l . X V , f i g . 5; p l . X V I , f igs 4 - 6 . 1980. P tychophyl loceras f l abe l l a tum ( N E U M A Y R , 1871) — G A L Á C Z , p . 45, p l . V I , figs 2 -3 ;

p l . V I I , f i g . 2; t e x t - f i g s . 35 -36 . (cum syn . )

Desc r ip t i on : T h e r e are two col lec ted specimens i n the m a t e r i a l , both w o r n out on one s ide . The bigger i s of c a . 83 m m i n d iamete r , the s m a l l e r one is c a . 57 m m . Both specimens are w h o l l y septate and p re se rve some r e c r y s t a l l i z e d s h e l l . The u m b i l i c u s is na r row , the p e r i u m b i l i c a l s ides f o r m funnel-shape depress ion . The flanks are modera te ly convex, the venter i s b roadly a r ched .The pa r t s of l ack ing the shel l on the b igger specimen show the p e r i u m b i l i c a l rose t te fo rmed by sha l low, projected c o n s t r i c t i o n s , which disappear around the midd le of the w h o r l - s i d e s . On the upper p a r t of the flanks and on the venter the l a b i a l r idges are c l e a r l y v i s i b l e . E n t i r e suture l ines cannot be seen. Remarks : P . f l abe l l a tum, the type of wh ich came f r o m the Bathonian of Swini tza (Romania), i s a common element i n Medi te r ranean Bathonian and C a l l o v i a n faunas. I t was descr ibed f r o m S i c i l y by G E M M E L A R O (1872, p . 172, p l . I I , figs 1-2), under the name P . euphyl lum, and recorded by A R K E L L (1954, p . 278) and WENDT (1963) i n severa l faunal l i s t s .

Suborder A M M O N I T I N A Hyatt , 1889 Superfamily H ap 1 oc e r a t ac e ae Z i t t e l , 1884 F a m i l y Oppeli idae B o n a r e l l i , 1894 Subfamily Hect icocera t inae Spath, 1925 Genus Prohec t i coceras Spath, 1928

Prohec t i coce ras haugi ( P O P O V I C I - H A T Z E G , 1905) (Plate I I , F igs 2a-b)

1905. Hect icoceras haugi n . sp . — P O P O V I C I - H A T Z E G , p . 18, p i . 4, f i g . 3; p i . 5, f igs 2 - 1 0 . 1972. P rohec t i coceras haugi ( P O P O V I C I - H A T Z E G ) ~ K R Y S T Y N , p . 244, p i . 6, f i g . 1 ; t e x t - f i g . 1 .

(cum s y n . )

Desc r ip t i on : A s ing le , w e l l - p r e s e r v e d i n t e r n a l cast w i t h r e c r y s t a l l i z e d s h e l l . The specimen i s sep­tate up to the greatest p rese rved d i a m e t e r (72 m m ) , where the measurements a re : 40 (55.5%); 21 (29%); 10 (14%). The c o i l i n g i s v e r y invo lu te , the n a r r o w u m b i l i c u s has h igh , pe rpendicu la r wa l l s and rounded u m b i l i c a l m a r g i n . The w h o r l - s e c t i o n i s h i g h - t r i a n g u l a r , w i t h flattened f lanks and s l igh t ly elevated, double s p i r a l band at the l o w e r t h i r d of the w h o r l - h e i g h t . T h e venter i s n a r r o w , t e c t i f o r m , w i t h a blunt k e e l . The r i b b i n g consis ts o f shor t blunt p r i m a r y r i b s on the inner p a r t of the flank, and cu rved r u r s i r a d i a t e secondaries on the outer w h o r l - s i d e s . The secondaries end i n strengthened t e rmina t i ons on the v e n t r o l a t e r a l m a r g i n . The f i r s t ha l f of the l a s t p rese rved w h o r l bears 10 p r i m a r y and 31 secondary r i b s . The p r i m a r y and secondary r i b b i n g s ta r t s fading at c a . 47 m m d iamete r , w i t h weakening of the p r i m a r i e s and d isappear ing of the s tems of some second­a r i e s . C e r t a i n s u r v i v i n g secondary r i b s apparent ly r e m a i n at g rea te r d i ame te r s , but the p r e s e r v a ­t ion does not a l low one to see t hem c l e a r l y . No suture l i ne can be seen.

Remarks : P . haugi is a c h a r a c t e r i s t i c ammoni te i n Midd le and basal Upper Bathonian f aunas ,wi th m a x i m a l abundance in the Hodsoni Zone (Retrocosta tum Zone auc t t . ; see TORRENS, 1971). Howe ver , the type ( P O P O V I C I - H A T Z E G , 1905, p l . V , figs 8a-c) came f r o m the Strunga fauna (Romania), which i s a condensed m a t e r i a l of m a i n l y deeper Bathonian e l emen t s .

The genus Prohec t i coce ras i s c o m m o n l y represented i n Bathonian faunas f r o m S i c i l y . A R K E L L (1954) recorded severa l species f r o m Monte Bonifato , and WENDT mentioned other occur rences i n Monte E r i c e (1963, p . 68; 1971, p . 60 ) .

F a m i l y L issocera t idae Douvillé, 1885 Genus L i s soceras Bayle , 1879

L i s soce ra s (L i s soce ras ) f e r r i f e x ( Z I T T E L , 1868) (Plate I , F igs 5a-b)

1868. Ammoni t e s f e r r i f e x n . sp . - - Z I T T E L , p . 604. 1980. L i s soce ra s f e r r i f e x ( Z I T T E L , 1868) — G A L Á C Z , p . 60, p l . X H I , f i g . 1 ; t ex t - f i g s 4 7 - 4 8 .

(cum syn . )

D e s c r i p t i o n : T h i s w e l l - p r e s e r v e d , m e d i u m - s i z e d ammoni te i s an e n t i r e l y septate phragmocone w i t h preserved r e c r y s t a l l i z e d s h e l l . I t measures , at 58 m m d i ame te r : 28 (48%); 23 (40%); 8.5 (15%).

T h i s t y p i c a l L i s soce ras has a n a r r o w u m b i l i c u s , h igh and arched u m b i l i c a l w a l l , rounded u m b i l i c a l margin . i s l i g h t l y convex flanks and somewhat f lat tened ven te r . The w h o r l s are comple te ly s m o o t h . E n t i r e suture l ine cannot be seen, but po r t ions o f the c h a r a c t e r i s t i c hap locera t id suture are v i s i b l e . R e m a r k s : L . f e r r i f e x , the type o f w h i c h came f r o m the condensed Bathonian of Swini tza , ia f a i r l y c o m m o n i n Medi t e r ranean Bathonian faunas. The species was descr ibed f r o m S ic i l y by WENDT (1963, p . 20), however that f o r m i s p robab ly a specimen of L . o o l i t h i c u m . on the basis o f i t s wide u m b i l i c u s and di f ferent suture l i ne (see G A L Á C Z , 1980, p . 6 0 ) .

Super fami ly S t e p h a n o c e r a t a c e a e Neumayr , 1875 F a m i l y Stephanoceratidae Neumayr , 1875 Subfamily Cadomit inae Wes te rmann , 1956 Genus Cadomites M u n i e r - C h a l m a s , 1892

Cadomites (Polypiec t i t es ) cornutus KOPIK, 1974 (Plate I , F i g s 6a-b)

1974. Cadomites (Polyplec t i tes ) cornutus sp . n . — K O P I K , p . 29, p l . V H I , f igs 3 . a -d ; p l . DÎ, f i g . 7; t ex t - f i g s l . a - d .

1983. Cadomites (Polyplect i tes) cornu tus K O P I K , 1974 — S A N D O V A L , p . 299, p i . 23, f i g . 7; t e x t - f i g . 108-F (only)

D e s c r i p t i o n : A s m a l l , w h o l l y septate, w e l l - p r e s e r v e d spec imen . The d imens ions at 31 m m m a x i m a l p re se rved d i ame te r are 12 (39%); 18 (58%); 10 .5 (34%). The specimen i s p robab ly a nea r ly en t i r e phragmocone, as indicated by the beginning o f a s l i gh t e x c e n t r i c i t y shown i n the u m b i l i c a l seam o f the las t p r e se rved p a r t . The u m b i l i c u s i s modera te ly n a r r o w , deep, w i t h rounded u m b i l i c a l w a l l . The w h o r l - s i d e s are convex, the venter i s b road ly a r c h e d . The scu lp ture cons is t s o f projec ted and f o r w a r d l y arched p r i m a r y r i b s ending i n s m a l l , sharp tuberc les somewhat below the midd le of the w h o r l - s i d e . The number of p r i m a r i e s i s 31 on the las t p rese rved w h o r l . The densi ty of the p r i m a r y r i b s i s v a r i a b l e , there are segments w i t h denser and others w i t h s l i g h t l y spa r se r costae . The t u ­berc les are furca t ion points fo r dense, sharp secondary r i b s . The las t w h o r l bears 110 secondary r i b s , i . e . the s e c o n d a r y / p r i m a r y r i b r a t i o i s 3 . 5 .

Suture l ine cannot be seen because of the presence of r e c r y s t a l l i z e d she l l throughout the w h o r l s . R e m a r k s : C . ( P . ) cornutus , desc r ibed f r o m the P o l i s h L o w e r Bathonian, Is p robab ly a species of w i d e r geographic d i s t r i b u t i o n . Recent ly i t was r ecorded f r o m Spain (SANDOVAL 1983). F r o m the Bet ic C o r d i l l e r a s S A N D O V A L f igured a l a rge Po lyp lec t i t e s f r o m the Upper Bajocian ( loc . c i t . p . 20, f i g . 4), wh ich i s regarded here as non conspec i f i c . A s i m i l a r f o r m i s C . ( P . ) z l a t a r s k i i . also of L o w e r Bathonian, but th is species i s s m a l l e r , showing the end of the phragmocone at c a . 25 m m , and has a denser r i b b i n g (see G A L Á C Z 1980, p . 76) .

The subgenus Po lyp lec t i t e s i s w e l l - r e p r e s e n t e d i n S i c i l y (see W E N D T 1963). The f o r m f igured by W E N D T ( l o c . c i t . , p . 132, p i . 2 1 , f igs 2 . a -b ) i s s i m i l a r but s m a l l e r , w i t h a contrac ted body chamber w h i c h begins at c a . 21 m m d i a m e t e r .

C . ( P . ) cornutus seems to be r e s t r i c t e d to the L o w e r Bathonian, j u s t as many other s m a l l -sized Cadomites microconchs i n the Med i t e r r anean r e g i o n .

Super fami ly P e r i s p h i n c t a c e a e Steinmann, 1890 F a m i l y Per i sph inc t idae Steinmann, 1890 Subfamily Pseudoperisphinct inae Schindewolf, 1925 Genus Choffatia S lemiradzki i , 1898

Choffatia (Subgrossouvria) u r in i acens i s (LISSAJOUS, 1923) (Plate n , F i g . 3)

1923. Pers iph lnc tes (Grossouvr la ) u r i n i a c e n s i s M . LISSAJOUS — LISSAJOUS, p . 69, p l . V I I , f i g . 3; t e x t - f i g . 12 .

1980. Choffat ia (Subgrossouvria) u r i n i a c e n s i s (LISSAJOUS, 1923) — G A L Á C Z , p . 128, p l . XXXP7 , f i g . 3; t e x t - f i g . 109.

? 1983. Choffat ia (Subgroasouvrla) u r in i acens i s (LISSAJOUS, 1923) — S A N D O V A L , p . 517, p i . 60, f i g . 2; t e x t - f i g . 1 4 3 . C .

D e s c r i p t i o n : M e d i u m - s i z e d p e r i s p h i n c t i d , w i t h 82 m m m a x i m a l p rese rved d i ame te r , where o ther measurements a r e : 23 (28%); 29 (35%); 43 (52%). The c o i l i n g i s e x t r e m e l y evolute , w i t h wide and shal low u m b i l i c u s , convex u m b i l i c a l w a l l and flanks, and rounded, broad ven te r . The r i b b i n g c o n ­s i s t s of ve ry s t rong , wide ly-spaced r a d i a l o r s l i g h t l y p ro jec ted p r i m a r y r i b s , wh ich branch in to low, rounded secondaries near to the v e n t r o l a t e r a l m a r g i n . The last w h o r l bears 20 p r i m a r y r i b s , and each p r i m a r y gives r i s e to 4 secondar ies . The inne r w h o r l shows d i f fe ren t r i b b i n g , i . e . the i nne rmos t p re se rved w h o r l has dense s t rong r a d i a l i n n e r r i b s . The change i n the r i b b i n g s ty le ap­pears abrup t ly , at c a . 15 m m u m b i l i c a l d i a m e t e r . One of the most c h a r a c t e r i s t i c features of the species i s the presence of s t rong, deep and wide cons t r i c t i ons p a r a l l e l to the p r i m a r y r i b s , where the w h o r l - t h i c k n e s s suddenly grows c o n s i d e r a b l y . Each w h o r l shows 3 c o n s t r i c t i o n s . Suture l ine cannot be seen, and the end of the phragmocone cannot be d i s t ingu i shed . R e m a r k s : The s t r a t ig raph ie d i s t r i b u t i o n of th is species has been recen t ly discussed e lsewhere (see G A L Á C Z 1980, p . 129), and th is p roved that C . (S.) u r in i acens i s i s a Midd le Bathonian, Subcon-t r ac tus Zone f o r m . The recent r e c o r d f r o m Spain (SANDOVAL 1983) r e f e r s to a s l i g h t l y d i f ferent ammoni te showing weaker r i b b i n g and sha l lower c o n s t r i c t i o n s .

T h i s species was f i r s t r ecorded f r o m S i c i l y (Monte I n i c i ) by A R K E L L (1954, p . 279; 1956, p . 208), then W E N D T (1963, p . 83) ment ioned i t f r o m Monte Boni fa to .

F a m i l y Morphocera t idae Hyatt , 1900 Genus Morphoceras Douvillé, 1880

Morphoce ras m u l t i f o r m e A R K E L L , 1951 (Plate I I , F i g . 4)

1 9 5 1 . Morphoce ras m u l t i f o r m e n o m , nov . — A R K E L L , p . 17 . 1955. Morphoceras m u l t i f o r m e A R K E L L — A R K E L L , p . 132, p i . 16, f igs 1-2; t e x t - f i g s . 47, 50

(cum s y n . ) 1970. Morphoce ras m u l t i f o r m e A R K E L L — H A H N , p . 33, p i . 5, f i g s . 1-5; t e x t - f i g . 7. (cum s y n . )

D e s c r i p t i o n : The avai lable single specimen i s a badly p rese rved fragment o f a c a . 25 m m d i ame te r example, wh ich shows some of the diagnost ic features c l e a r l y . I t i s w h o l l y septate, the u m b i l i c u s i s na r row , w i t h steep u m b i l i c a l w a l l , abrupt u m b i l i c a l edge. The w h o r l - s i d e s are convergent , the venter cannot be seen. The f ine, rounded r i b s a r i se on the u m b i l i c a l m a r g i n , pro jec ted on the inne r p a r t of the f lank and become r a d i a l t oward the ven t e r . The c h a r a c t e r i s t i c n a r r o w , s t rong ly pro jec ted c o n s t r i c t i o n s cut the r i b b i n g i n the t y p i c a l Morphoce ra t i d s t y l e . Suture l ines are not v i s ­i b l e . R e m a r k s : The species was discussed r ecen t ly i n de t a i l i n severa l monographs ( A R K E L L 1951-59, M A N G O L D 1970, H A H N 1970). I ts s t r a t ig raph ie range is r e s t r i c t e d to the l o w e r p a r t of the Zigzag Zone (see TORRENS 1971). Morphoce ra t ids were f i r s t r ecorded f r o m S i c i l y by A R K E L L (1954, p . 279) . WENDT (1963,, p . 81) found s i m i l a r faunas.

F a m i l y T u l i t i d a e Buckman, 1921 Genus Rug i f e r i t e s Buckman, 1921

Rug i fe r i t e s (Rugifer i tes) n . s p . , aff . R . ( R . ) polypleurus ( B U C K M A N ) (Plate I I , F i g . 1)

af f . 1921-1923. P leu rophor i t e s po lyp leurus n o v . — B U C K M A N , p . 47, p i . 3 7 1 . af f . 1971 . T u l i t e s (Rugifer i tes) po lyp leurus ( S . B U C K M A N ) — H A H N , p l . 3, f i g , 6 . (cum syn . )

D e s c r i p t i o n : A s ing le , f ragmentary , incomple te spec imen . The m a x i m a l d i a m e t e r i s c a . 72 m m , the measurements at 60 m m d i a m e t e r a re : 25 (42%); c . 42 (c . 70%); 18 (30%). The c o i l i n g i s evolute for the genus, the u m b i l i c u s i s deep, w i t h s l i g h t l y convex u m b i l i c a l w a l l ; the flanks and the venter are rounded . The r i b b i n g i s dense, w i t h 39 p r i m a r y r i b s a r i s i n g at the u m b i l i c a l s eam. The p r i m a r i e s are r a d i a l on the u m b i l i c a l w a l l , then become p r o r s i r a d i a t e on the u m b i l i c a l m a r g i n . The secondary r i b b i n g appears h igher up on the f lanks , the secondaries are low, nea r ly flat tened, and curve backward to c ross the venter p e r p e n d i c u l a r l y . On the body chamber the secondary r i b b i n g becomes s l i g h t l y r u r s i r a d i a t e . Genera l ly the s e c o n d a r y / p r i m a r y r i b r a t i o i s 2 , 0 , but some r ib s t r i f u r c a t e , w h i l e c e r t a i n p r i m a r i e s are continuous up to the ven te r . The s t rength of the p r i m a r y r i b s va r i e s , i . e . the re are some t h i c k e r , s t ronge r r i b s ending i n bulks at the fu rca t ion p o i n t . The

i nne r and the m i d d l e w h o r l s show i r r e g u l a r l y - s p a c e d c o n s t r i c t i o n s , and here parabol ic nodes are associated on the r i b s . Suture l ines cannot be seen.

R e m a r k s : The spec imen shows c o i l i n g and r i b b i n g c h a r a c t e r i s t i c fo r R u g i f e r i t e s . The e x t r e m e l y high number of the r i b s indicates a new species, however the s ingle avai lable specimen i s i n s u f f i ­c ien t to designate one . The nearest f o r m i s R . po lyp leurus ( B U C K M A N ) , w h i c h i s the most densely r ibbed species h i t h e r t o descr ibed , but the here f igured f o r m shows m o r e numerous r i b s , f u r ca t i on point i n lower p o s i t i o n and cons t r i c t i ons and parabol ic nodes enduring up to the penul t imate w h o r l .

R . po lyp leu rus , as w e l l as a l l known Rugi fe r i t e s , i s known only f r o m the Midd le Bathonian, a lmost exc lus ive ly f r o m the lower p a r t of the Subcontractus Zone. I ts occur rence i n th is fauna i s a good argument fo r i den t i fy ing the M i d d l e Bathonian.

The single f igu red Rugi fe r i t e s f r o m S ic i l y i s that o f WENDT (1963, p p . 69, 137, p i . 20, figs 5 .a-b) f r o m E r i c e . T h i s ammoni te , however, seems to belong to the genus B u l l a t i m o r p h i t e s . M o r e s ign i f i can t ly , W E N D T (1965, p . 290) included i n an Aa len i an -Ca l lov i an condensed faunal l i s t " T u l i t e s (Rugifer i tes) af f . polypleurus (Buckman)" , w h i c h i s a good co inc idence .

X X X X X

Note: A l l specimens ment ioned, desc r ibed o r f igured i n t h i s paper are deposited i n the c o l l e c t i o n

of the Palaeontologica l Depar tment o f the Hungarian Na tu ra l H i s t o r y Museum, Budapest .

REFERENCES

A R K E L L , W . J . (1951-59): A monograph of the Eng l i sh Bathonian A m m o n i t e s . - Palaeont . Soc. , C I V - C X I I : i - v i i i + 1 - 2 6 4 .

A R K E L L , W . J . (1954): The ammoni te faunas. I n : W A R M A N , H . R . and A R K E L L , W . J . : A r e v i e w of the Jurass ic o f wes te rn S i c i l y based on new ammoni t e faunas. - Q u a r t . J . G e o l . Soc. , 110 (439): 2 7 6 - 2 8 1 .

A R K E L L , W . J . (1956): Ju rass ic Geology of the W o r l d . - O l i v e r and Boyd, Ed inburgh , 806 p p . B U C K M A N , S.S. (1909-30): ( Y o r k s h i r e ) Type A m m o n i t e s . 1-7 - London, 790 p i s . C A T A L A N O , R . & D ' A R G E N I O , B . (1981): Paleogeographic Evo lu t i on of a Cont inenta l M a r g i n i n

S i c i l y . Guide Book of the Field t r i p i n Western S i c i l y , Sept. 12-14, 1 9 8 1 . - P a l e r m o , 142 p p . C A T A L A N O , R . & D* ARGENIO, B . (1982): Guida a l la Geológia délia S i c i l i a Occ identa le . - M e m .

Soc. Geo l . I t a l . , Suppl . A . X X I V : 1-155.

G A L Á C Z , A . (1980): Bajoc ian and Bathonian ammonites o f Gyenespuszta, Bakony M t s . , Hunga ry . -Geo l . H u n g . , Se r . Pa laeont . , 39: 1-227.

G E M M E L L A R O , G . G . (1872): Sopra i Cefalopodi délia zona con Stephanoceras m a c r o c e p h a l u m . -A t t i . A c a d . Gioenia , Ser . 3, V I I I : 165-202.

H A H N , W . (1970): Die Park insoni idae S. Buckman und Morphocera t idae Hyat t (Ammonoidea) des Bathoniums (Braune r J u r a epsi lon) i m südwestdeutschen J u r a . - J h . G e o l . Landesamt Baden-Württemberg, 12: 7 -62 .

H A H N , W . (1971): Die T u l i t i d a e S .Buckman , Sphaerocerat idae S .Buckman und Clydonicera t idae S .Buckman (Ammonoidea) des Bathoniums (Brauner J u r a epsi lon) i m südwestdeutschen J u r a . -J h . G e o l . Landesamt Baden-Württemberg, 13: 55-122 .

K O P I K , J . (1974): Genus Cadomites M u n i e r - C h a l m a s , 1892 (Ammoni t ina ) i n the Upper Bajocian and Bathonian of the C r a c o w - W i e l u n Ju ras s i c range and the Gory Swie tokrysk ie Mountains (Southern Poland) - I n s t . G e o l . B i u l . , 276 (7): 7-53.

K R Y S T Y N , L . (1972): Die Obe rba joc ium- und B a t h o n i u m - A m m o n i t e n des Klaus-Schichten des S te in ­bruches NeumUhle bei Wien (Österreich). - A n n . N a t u r h i s t . M u s . Wien , 76: 195-310.

LISSAJOUS, M . (1923): Étude sur l a faune du Bathonien des env i rons de Maçon. - T r a v . L a b . Géol . U n i v . Lyon , 3: 1-286.

M A N G O L D , C . (1970): Morphocera t idae (Ammoni t i na - Per i sphinc taceae) Bathoniens du J u r a Méridionale, de l a Nièvre et du P o r t u g a l . - Géobios, 3 (1): 43-130.

N E U M A Y R , M . (1871): Die Phy l loce ra ten des Dogger und M a l m . - J b . k . k . G e o l . Re ichsans t . X X I (3): 297-354 .

P O P O V I C I - H A T Z E G , V . (1905): Les céphalopodes du Jurass ique du Mont Strunga (Mass i f de Bucegi , Roumanie ) . - M é m . Soc. Géol. F r a n c e (Paléont.) , 13_ (35): 1-28.

S A N D O V A L , J . (1983): B i o e s t r a t i g r a f i a y paleontológia (Stephanocerataceae y Per isphinctaceae) de l Bajocense y Bathonense en las C o r d i l l e r a s B e t i c a s . - U n i v . Granada, 613 p p .

TORRENS, H . S . (1971): Standard zones of the Bathonian - C o l l . Jurass ique Luxembourg , M é m . B . R . G . M . , N o . 7 5 : 581-604.

W E N D T , J . (1963): Stratigraphisch-paläontologische Untersuchungen i m Dogger W e s t s i z i l i e n s . -B o l l . Soc. Pa leon t . I t a l . , 2 (1): 57-145.

W E N D T , J . (1965): Synsedimentäre Bruch tek ton ik i m J u r a W e s t s i z i l i e n s . - N . J b . G e o l . Paläont. , M h . , 1965: 2 8 6 - 3 1 1 .

W E N D T , J . (1969): Die stratigraphisch-paläontologlsche En twick lung des J u r a i n W e s t s i z i l i e n . -Geo l . Rundschau, 58 (3): 735-755.

W E N D T , J . (1971): Geológia de l Monte E r i c e ( P r o v i n c i a d i T r a p a n i , S i c i l i a Occidenta le) . - G e o l . R o m . , X : 53 -76 .

Z I T T E L , K . A . (1868): Paläontologische Not izen über L i a s - , J u r a - und Kre ide-Schich ten i n den ba ie r i schen und österreichischen A l p e n . - Jb . k . k . G e o l . Re ichsans t . , 1_8: 599-610.

A u t h o r ' s address : D r . András G A L Á C Z Depar tment of Paleontology Eötvös Loránd U n i v e r s i t y H-1083 Budapest Kun Béla tér 2 . HUNGARY

E X P L A N A T I O N OF P L A T E S

P L A T E I .

F i g s 1-2: P tychophy l loce ras f l abe l l a tum ( N e u m . ) , 1 : M . 8 4 . 1 0 5 ; 2: M . 8 4 . 1 0 4 .

F igs 3-4: P h y l l o c e r a s t r i f o l i a t u m N e u m . , 3: M . 8 4 . 1 0 3 ; 4: M . 8 4 . 1 0 2 .

F igs 5a-b: L i s s o c e r a s f e r r i f e x ( Z i t t . ) , M . 8 4 . 1 0 6 .

F igs 6a-b: Cadomi tes (Polyplec t i tes ) cornutus Kop ik , M . 8 4 . 1 0 8 .

( A l l f igures i n na tu r a l size)

P L A T E n .

F i g . 1: R u g i f e r i t e s (Rugifer i tes) n . s p . aff . R . ( R . ) po lyp leurus ( B u c k m . ) , M . 8 4 . 1 0 9 .

F igs 2a-b: P rohec t i coce ra s haugi ( P o p . - H ä t z . ) , M . 8 4 . 1 0 7 .

F i g . 3: Choffat ia (Subgrossouvria) u r in i acens i s ( L i s s . ) , M . 8 4 . 1 1 1 .

F i g . 4: Morphoce ra s m u l t i f o r m e A r k e l l , M . 8 4 . 1 1 0 .

(AU f igures i n na tu ra l size)

PLATE I .

PLATE I I .


Recommended