Bulletin de la Société belge de Géologie T. 95 fasc. 4 pp. 257-280 Bruxelles 1986 Bulletin van de Belgische Vereniging voor Geologie V. 95 dee l 4 blz. 257-280 Brussel 1986
CONODONT SUCCESSION ACROSS THE TOURNAISIAN-VISJ;:AN BOUNDARY BEDS AT SALET, BELGIUM
by Zdzislaw BELKA (*) and Eric GROESSENS (**)
KEY WORDS Conodonta, Tournaisian, Visean, Boundary, Salet, Dinant Synclinorium,
I l'HRODIJCT I OM, The taxonorny of the conodont This study offers a rev1s1on of genera as SiphonodeZZa, Gnathodus, PseudopoZyg the conodont fauna recovered frorn the nathus, ScaZiognathus, Mestognathus , that ex section called "Route de Salet" which is hibi t a great importance for the Lower exposed along the Molignée Valley, in a Carboniferous stratigraphy have recently small quarry and it continues along the been revised by SANDBERG et aZ. (1978), road to Salet (Text-figs 1-2). The pre LANE, SANBERG, ZIEGLER (1980), Helka cise location and accessibility of this (1983) and LANE & ZIEGLER (1983). New exposure is given by CONIL & GROESSENS concept of several species as well as (1974 : 24), GROESSENS (1975 : 45) and descriptions of new taxa stirnulated us to HANCE (1985). It is a classical and one re-investigate the conodon~ occurring in of the rnost important sections for the the classical sections of the Dinant Syn Lower Carboniferous stratigraphy. As a cl inoriurn. The purpose of this study is parastratotype section for the Lower also to atternpt an application, in the Viséan (CONIL, 1967) it attracted the Dinantian type area, of the prelirninary interest of many workers being the area standard conodont zonation proposed by of an intense search for microfossils LANE, SANDBERG & ZIEGLER (1980) for the (see HANCE, 1985). Several foraminiferal post- SiphonodeZZa interval. taxa (cf. CONIL & LYS, 1964) have been
0 5 10km
Fig. 1 - General location map. Patterned area shows extent of the Carboniferous deposits in the Din~nt Synclinorium.
( *) Institute of Geology, University of Warsaw, Al. Zwirki i Wigury 93, 02-089 Warszawa (Poland).
( **) Geological Survey of Belgium, 13 rue Jenner, B-1040 Brussels (Belgium).
257 described from this exposure for the first grains. The Leffe facies extends land time and it is also a type locality for wards for many kilometers away from the two stratigraphically important conodont buildups (LEES & CONIL, 1980; LEES, 1982) species, DoUymae bouckaerti GROESSENS and and it always separates the latter from Eotaphrus buUyneki ( GROESSENS). The holoty the Molignée faciès. types of these conodonts are reillustrat ed- herein. The Calcaire de la Molignée forms the upper unit sampled for cono The section at Salet (Text- donts in the "Route de Salet" section. fig. 2), moreover, is a type section for The limestones are wackestones and lime two lithostratigraphical units of the mudstones with numerous shaly interbeds. classic Dinantian of Belgium, the Calcaire The composition of allochems is similar Noir de la Malignée (GROESSENS, 1975) and to that-of the Leffe facies, but from the the Calcaire de Salet (GROESSENS, CONIL & 'Bed 87 the increase of foraminifers in LEES, 1976). The base of the Moliniacian, place of bryozoans is noted to occur .. i.e. the stage of the Viséan, locally dis According to HANCE (1985 : 182), the lower tinguished in Belgium, was also defined part of the Calcaire de la Molignée at here at the Bed 52 (PAPROTH et al., 1983 : Salet reflects regressive conditions, 188) . whereas the Viséan transgression is indi cated much later by the first appearance The investigated conodont fauna of the foraminiferal fauna dominated by includes the raaterial collected and ori the Archaediscidae in the Bed 215. ginally described by GROESSENS (1971, 1975) and also conodonts obtained during additional recent sampling that produced CONODONT DISTRIBUTION, some new conodont occurrences. The sam ples were collected from the lower por Very closely sampling of long tion of the sequence only up to the Bed intervals in the "Route de Salet" section 285 where there occur slump structures provided substantial account of conodont at the top of the Calcaire de la Molignée succession in the late Tournaisian and (Text-fig. 2). early Viséan strata. Although the observ ed occurrences of the majority of cono dont species (Table 1) agree with their LITHOLOGY, recognized stratigraphie ranges (cf. LANE, SANDBERG & ZIEGLER, 1980), some species, At Salet, a 320 meter thick however, demonstrate new occurrences that section of the Lower Carboniferous carbo appear to be very significant for the nates is exposed, but only 130 m were phylogeny of these species and for the covered by this study. The investigated Lower Carboniferous conodont stratigraphy. portion of the section consists of three iithological units (Text-fig, 2) that The most remarkable is the first constitute proximal lateral equivalents appearance of Gnathodus texanus , a zonal of the Waulsortian facies (cf, LEES, marker of the texanus Zone. The lower 1984). range of this species was- known to start simultaneously with the extinction of The lowest unit is developed as Scaliognathus anchoraUs (LANE, SANDBERG & crinoidal and bryozoan packstones that are ZIEGLER, 1980 : Tab. 2; LANE & ZIEGLER, massive or interbedded with thin shales in 1983). In contrast, G, texanus occurs at the lower part of this unit. These sedi Salet just below the appearance of ments pass laterally into the Bayard fa Scaliognathus anchoralis europensis (Text-fig. cies considered to be located in the 3). Similary to that, the ranges of both neighborhood of the Waulsortian buildups. species are recently noted to overlap in the Dinantian rocks of southwestern Ire Overlying is the Leffe facies, land (THORNBURY, 1985) and VARKER & which comprises well-bedded wackestones SEVASTOPULO (1985 : Tab. 6) indicated and packstones that contain various allo that for the Lower Carboniferous conodonts chems and first of all peloids, bioclasts in Britain and Ireland the range of of echinoderms and bryozoans, and coated Gnathodus texanus extends from the middle
s N , Mohgnee.
1 1 0 w Ol 0 0 - 0 10 2om Bioul 22 Bioul 8 ~ 1
Fig. 2 - The lower part of the "Route de Salet" section sampled for conodonts. Black triangle indicates the position of the Tournaisian-Viséan boundary. Bed numeration after Overlau et Conil, 1965. 258 part of the anchoraZis Zone. The record of conodont zones in the Tn3a-V1b inter of G. texanus at Salet does not appear to val has also been outlined at that time. be a freak of nature. It is well docu These zones were incorporated later by mented in our fauna by transitional forms AUSTIN (1973) into his proposa! of the (see Table 1 and Pl. 6, Figs 7-9) showing Dinantian conodont zonation suggested the evolutionary relation between Gnathoclus for application in Europe. semiglaber and Gnathodus texanus. The former species gave rise to G. texanus by the re The conodont zonal scheme for duction of the inner parapet and platform the Lower Carboniferous currently used ornamentation. The reduction trend of in Belgium was established by GROESSENS morphological changes in the conodont (1975). Recently, it was in part modif platform, as late Tournaisian gnathodon ied to produce some new detailed sub tan Pa elements display (BELKA 1984 : fig. divisions (PAPROTH et al., 1983 : Tab. 10; 1985b) is also exemplified by the 2). Although the usefulness of this origin of Gnathodus pseudosemigZaber from G. scheme for the Belgian stratigraphy cuneiforms. This is indicated by transi- "'remains unquestionable, i ts global appli tional forms (Pl. 5, Figs. 4-9) as well as cation proves to be limited. This is by ontogenetic development of small spe because some species used for definition cimens of G. pseudosemiglaber which recapi of subzones (e. g. Dollymae hassi, Dollymae tulate a character of G. cuneiformis. To bouckaerti, Eotaphrus bultyncki) are rather show phyletic sequence of above mentioned rare out of Belgium while other index species of Gnathodus, the transitional forms as Polygnathus communis carinus and forms are separately presented in Table 1, Eotaphrus burlingtonensis appear in Belgium but they are not considered herein to be significantly later than their lower the separate species. ranges recognized in many Lower Carboni ferous sections (see LANE, SANDBERG & The other anomaly which is ZIEGLER, 1980). Undoubtedly, this is worthy to note, is the record of Pseudo why the framework of the world-wide pre polygnathus pinnatus. This species (Pl. 2, limina ry standard conodont zonation Fig. 9) yields earlier appearance relative (SANDBERG et al., 1978; LANE, SANDBERG to Pseudopolygnathus oxypageus, Dollymae & ZIEGLER, 1980) differs considerably bouckaerti, and Eotaphrus bultyncki. It is from that recognized in Belgium by much earlier than was recognized by LANE, GROESSENS (1975). SANDBERG & ZIEGLER (1980 : Tab. 2) but identical range of Ps. pinnatus reflecting, The investigated section yields most probably, an actual stratigraphie all diagnostic forms which allowed to range of this species is recorded from identify all the conodont zones of Upper Britain and Ireland (VARKER & SEVASTOPULO Tournaisian and Lower Viséan strata sensu 1985: Tab. 6). GROESSENS (1975), i. e. the carinus Zone, the anchoralis Zone, and the beckmanni The genus Scaliognathus is repre Zone (Text-fig. 3), and also to correlate sented by Sc. praeanchoralis (Pl. 1, Fig. this section with other successions of 7), Sc. anchoralis fairchildi (Pl. 1, Figs, Belgium (GROESSENS, 1975; GROESSENS, 8-11) and Sc. anchoralis europensis (Pl. 2, CONIL & LEES, 1976). Fig. 2). LANE & ZIEGLER (1983 : 205-206) suggested that Sc. a. europensis probably Of special interest in this developed from Sc. a. fairchildi although classical section, however, was also to the appearance of Sc. a. fairchildi before test up the preliminary standard cono Sc. a. europensis was not documented at that dont zonation. The results we received time. Now, such an evidence is recorded. show the scheme is to be corrected. In the "Route de Salet" section Sc. a, fairchildi cames 1. 5 m be fore Sc. a. europ The typicus Zone is recognized ensis. and its base is placed at the lowest occurrence of Gnathodus cuneiformis ( Bed The species Gnathodus homopunctatus, 22/69), the lower range of which appears which together wi th Mestognathus beckmanni is to be very close to that of Gnathodus considered to be diagnostic for earliest typicus Morphotype 2. In the investigat Viséan strata (GROESSENS 1975), appears ed section, the zonal name-bearer much later (Text-fig. 3) than in other appears erratically but much later than sections of the Dinant Basin. At the G. cuneiforms (see Table 1). Besides all Tournaisian-Viséan boundary stratotype in that the zone is well documented by Dinant i t occurs be fore M. beckmanni associated fauna including other gnatho following the Bed 141, at the base of dids, as well as Pseudopolygnathus pinnatus, which the boundary is placed (GROESSENS & Ps. oxypageus, Dollymae bouckaerti, and NOEL, 1977 : Pls 1-2). New data,however, Eotaphrus bultyncki. suggest that the range of G. homopunctatus may extend down to the middle of the In fact, the base of the typicus anchoralis Zone, as formerly recorded in Zone can be identified in Belgium as well the Moravia-Silesia Basin in Poland as in other regions of Europe by the (BELKA, 1985 : Fig. 3). first appearance of G. cuneiformis. Thus, i t is only proper to replace the typicus Zone by the cuneiformis Zone, as proposed CORRELATION, by BELKA (1985 : 46-47). The prominence of Gnathodus typicus in the studies of It was already the preliminary LANE, SANDBERG & ZIEGLER (1980) is not investigation of conodonts in several reflected within the composition of the sections of the Dinantian of Belgium Lower Carboniferous conodont faunas from (GROESSENS, 1971) that showed these micro Europe. Moreover, this species can be fossils as excellent guides for correla also difficult to recognize (THORNBURY, tion of the Tournaisian rocks. As are 1985 : 35-36). As a result of the exa sult, moreover, prospects of recognition mination of conodont fauna from Salet we
259 ï:: c tU Q) 87 E c .::t:. 0 Q; 0 N ..a Q) 77 rnl1l .0 .Ë Q) ~ (/1 0 ÇJ 65 "O :::J Q) , u (/1 57 a. VI SEAN ::l -"'c (/1 l1l TOURNAISIAN :::J )( "O 0 .2l G) .s:: 41 ïii c Q) c (/1 0 (!) :::J c "O 0 0 N N 36 .s:: ïii c (!) en "'tU... ·- 0 24 .... -C\'I .c Q; .. 0 CO 0 c ..>:: tU 0 .c :::J u ..a0 c 9 M C\'I ÇJ u 2
0/100 (/1 (/1 (/1 "ê :::J :::J "O 95 .l2 0 l1l ïii .s:: cJ -c: .... fi) c: c: CO G) :::J c: ·a 0 (!) Q) c c 88 .,; 0 0 a. N N 86
:::J en "'c .... E tU 0 .. 0 80 -G) c -- :::J ...... u C'l 74 uÇJ 69 1 ~r 55 h~)1 ~2 ~3 &iliÏ4
Fig, 3 - Ranges of the most important conodont taxa around the Tournaisian-Viséan boundary beds in the "Route de Salet" section M. - Mestognathus, Sc. a. - ScaZiognathus anchoraZis, F'r. - F'rotognathodus, Ps. - PseudopoZygnathus. The recognized standard conodont zones (on the right) are compared with those (on the left) of GROESSENS (1975) and CONIL, GROESSENS & PIRLET (1977). Lithology 1 - massive limestones, 2 - bedded limestones, 3 - bedded limestones with cherts, 4 - shales; for detailed lithology, see HANCE (1985).
260 expect that further studies will allow to recognition is based, first of all, on subdivide the cuneiformis Zone into two or such lithological evidences as the pre three parts. The records of easily reco sence of an important argillaceous marker gnizable forms as Protognathodus cordiformis, (cf.CONIL, GROESSENS & PIRLET, 1977) that PseudopoZygnathus pinnatus and/or DoZZymae occurs in the first meter above the bouckaerti seem to be very perspective. boundary. In terms of conodonts and fo raminifers the present position of the Since the species ScaZiognathus limit appears to be njustified. The anchoraZis has been subdivided to include order of ranges of conodonts such as three subsnecies, the base of the anchora ScaZiognathus anchoraZis europensis and Us Zone is-- defined by the first appearance Mestognathus beckmanni (Text-fig. 3) in relation of Sc. a. europensis (LANE, SANDBERG & to the appearance of the diagnostic for& ZIEGLER, 1980; LANE & ZIEGLER, 1983 : minifer Pachysphaerina pachysphaerica is Fig. 4). The zonal marker succeeds at identical to that in the Tournaisian Salet Sc. a. fairchiZdi (Table 1). There ~iséan Boundary Stratotype at Dinant fore, the base of the anchoraZis Zone must (cf. GROESSENS & NOEL, 1977 : Pl. 1). be taken 1.5 m higher than it was traced The taxon ScaZiognathus anchoraZis europensis out formerly (GROESSENS, 1975 : 46). The (together with HindeodeUa segaformis), new concept of this limit is more useful namely, ranges up to Bed 8/54 (Table 1) in comparison to that of GROESSENS (1975), i.e. 0.5 m higher than hitherto was re if there are disparities in lower ranges co gn i z e d, wh ile Mestognathus beckmanni of particular subspecies of ScaZiognathus starts in Bed 8/60. The foraminifer anchoraUs. Moreover, i t provides a mutual Pachysphaerina pachysphaerica the fi rs t control of this boundary by the occurren appearance of which is coincident at ces of other forms of the genus, such as Dinant with the Tournaisian-Viséan bound Sc. praeanchoraZis and Sc. a. fairchiZdi. ary, ranges from Bed 8/57 CHANCE, 1985 : Tab. 18) • The top of the anchoraZis Zone being the base of the next texanus Zone Al though the range of Mestognathus is identified by the first appearance of beckmanni in the stratotype section at Gnathodus texanus ( LANE, SANDBERG & Dinant is considered to be artificial ZIEGLER, 1980 : 120). As mentioned above, (LANE & ZIEGLER, 1983 : 210) the biostra this taxon appears in the investigated tigraphic data evidence that the section earlier than Sc. a. europensis Tournaisian-Viséan boundary at Salet (Table 1 and Text-fig. 3). Consequently, the should be displaced higher up to the base anchoraZis Zone would be to eliminate here of Bed 8/57 (see Text-fig. 3). if following the concept of LANE, SANDBERG & ZIEGLER. This zone, however, constitu tes the best recognized interval of the SYSTEMATIC PALEONTOLOGY. Lower Carboniferous that by means of cono donts can be traced throughout the world. All type material and figured Therefore, it is suggested to re-examine specimens are housed in the collection the concept of the texanus Zone in order of the Geological Survey of Belgium, to create-another zone of a global use Brussels. that will follow the anchoraUs Zone. As long as the stratigraphie ranges of other Genus Staurognathus BRANSON & MEHL, 1941. Viséan gnathodids are not satisfactorily documented, Mestognathus beckmanni can be TYPE SPECIES : Staurognathus cruciformis only tentatively used to define this zone. BRANSON & MEHL, 1941. The species Mestognathus beckmanni is inter preted to have lived in shallow-water REVISED DIAGNOSIS : biofacies (AUSTIN, 1976; BELKA, 1983 : 81-82) whereas the preliminary standard A genus characterized by an conodont zonation for the Lower Carbonife Icriodus-like P element with a long an rous is essentially based on deep-water terior process bearing a double row of conodonts. side denticles which may be fused to form transverse ridges. As many as two lateral processes and one shorter THE POSITION OF THE TOURNAISIAN-VISEAN posterior process may be developed to produce the typical cruciform outline. BOLINDARY, Lateral processes are straight or very The Tournaisian-Viséan boundary slightly concave anteriorly. They may as ratified by the Subcommission on Carbo also be ornamented by a double row of niferous Stratigraphy runs 34 meters below denticles on the upper surface. The the base of the Marbre Noir de Dinant and posterior process is generally curved it is located precisely at the base of in wardly. Bed 141 of the boundary stratotype section at Dinant (cf. CONIL et aZ., 1969). LANE REMARKS : & ZIEGLER (1983) discussed recently in detail the conodont occurrences around the The genus Staurognathus, as pre boundary in that section. As a consequen sently conceived, comprises two species ce ,they correlated the Tournaisian-Viséan St. cruciformis BRANSON & MEHL, and boundary with the preliminary standard St. dionantensis n. sp. which is described conodont zonation to put it within the herein. The another earlier described species, Staurognathus anchorarius !-IASS anchoraZis Zone. (1959) has been transferred by CHAUFF & In the "Route de Salet" section, KIAPPER (1978) to Bactrognathus as i t be ars the Tournaisian-Viséan boundary has been only a single row of denticles on the distinguished at the base of Bed 8/52 anterior process and it shows a morpholo (Text-figs 2 and 3) that forms the base gie gradation wi th B. excavatus. The spe of the Marbre Noir de la Mo lignée. The cies St. dionantensis appears to be an 261 ancestor of St. cruciformis, at it is STRATUM TYPICUM evidenced by a transitional form described by AUSTIN & GROESSENS (1972) as "New genus Bed of crinoidal packstone, B GROESSENS ---;. Staurognathus BRAN SON & MEHL". Bed 8/0 of the Route de Salet, 20 m below the base of the Marbre Noir de la Mol ignée. The both species of Staurognathus yield distinct exclusive geographic res LOCUS TYPICUS : triction in their distribution. The type species has so far been found to occur Salet, Molignée Valley, the widely in North America (BRANSON & MEHL, Ardennes; Belgium, 1941; COOPER, 1948; HASS, 1959; BURTON, 1964; THOMPSON, 1967; THOMPSON & FELLOWS, DIAGNOSIS : A species of Staurognathus charac 1970; LANE, SANDBERG & ZIEGLER, 1980; terized by only germinal development of CHAUFF, 1981). In contrast, St. dionanten- lateral processes. The posterior process sis as a very rare element was only re is marked by a group of nodes or a short ported from Belgium, Germany (cf. LANE, ridge that diverges (at the angle of 45°) SANDBERG & ZIEGLER, 1980), and Poland inwards from the axis of the anterior pro (BELKA, 1985a). The single Australian cess. The large open basal cavity flares spec imen of Staurognathus eruciformis (DRUCE, beyond the spindle. The posterior margin 1g70), represents, most probably, another of the basal cavity is corrugated to form species of the genus just as forms des three lobe-like extensions. cribed by CHAUFF (1985 : Figs. 1 .27 and 1 . 29 ) as Staurognathus aff. S. cruci f ormis . MATERIAL : 5 sepcimens. The hypothetic apparatus recons REMARKS : truction of Staurognathus cruciformis was Since the time when this element presented by CHAUFF (1981). Except for Pa has been recognized it is difficult to and Pb elements this apparatus is believed assign it, beyond any doubt, to any Lower to be identical with that of the genus Carboniferous conodont genus. This was Doliognathus. CHAUFF (1985 : 308) suggested, because it displays many similarities, moreover, that St. cruciformis have evolved but also differences to such genera as from an early form of D. latus. Icriodus, Eotaphrus, Staurognathus and Do Uymae (cf. GROESSENS, 1976). Recently, this The morphological similarities unit was commonly regarded as a possible between St. cruciformis and some forms of species of Eotaphrus, but lack of a large D. latus, as demonstrated by CHAUFF (1985), cusp, diagnostic for Eotaphrus, was notic are unquestionable. However, St. erueiformis ed. Although a resemblance to the genus with well-develoued lateral processes is Eotaphrus was suggested, a very close con known to occur stratigraphically below nection with the genus Staurognathus was the first appearance of Doliognathus latus also indicated (AUSTIN & GROESSENS, 1972). (see LANE, SANDBERG & ZIEGLER, 1980; Tab. 2; CHAUFF, 1981 : Text-fig. 3 and Tab. 2). LANE, SANDBERG & ZIEGLER (1980) We believe that the evolution of D. Zatus confined the stratigraphie range of this to develop an inner lateral process re species to the lower part of the anchoralis flects the general evolutionary trend ob ZÔne. The appearance of this species ear served among the uppermost Tournaisian lier than Scaliognathus a:nchoralis was, how conodonts to produce symmetrical Pa ele ever, known in Belgium (GROESSENS, CONIL ments. This trend is easily recognizable & LEES, 1976). Recently, in the Moravia in the evolution of the genus Scaliognathus Silesia Basin in Poland, a single specimen for instance (cf. LANE & ZIEGLER, 1983). of this species was found to occur at the base of tii.e cuneiformis Zone (BELKA, 1985a). RANGE : This record precedes considerably the Base of the cuneiformis Zone into lower limi t of Eotaphrus evae, which is the anchoralis Zone. considered to be the most primitive form of Eotaphrus. Thereby, a phylogenetic relation of the newly described species Staurognathus dionantensis n. sp. to the Eotaphrus lineage (as given by LANE, Pl. 1, Figs 1-2 SANDBERG & ZIEGLER 1980) seems to be doubt 1959 Icriodus Zatericrescens BRANSON & MEHL ? - ful. As a consequence, we assign this VOGES, p. 286 (specimens not illustrated). species to Staurognathus, on the basis of the tendency in morphologie ·gradation to 1971 N. GEN. B. - GROESSENS, p. 17, Pl. 2, Figs. form the cruciform outline. 5-6. 1980 Eotaphrus ? n. sp. V. - LANE, SANDBERG & The new species, Staurognathus ZIEGLER, Pl. 10, Figs. 9-10 (specimens from dionantensis n. sp. differs from St. cruci VOGES' collection). formis in lacking of well-developed poste rior and lateral processes. It resembles 1985 Eotaphrus ? sp. V of LANE, SANDBERG & Eotaphrus burlingtonensis, which can be, however, ZIEGLER. - BELKA, p. 37, Pl. 9, Fig. 6. distinguished by the prominent cusp at the posterior end. HOLOTY'PE : The origin of St. dionantensis is The specimen illustrated by problematic. Two forms, at first Peleksyg GROESSENS (1971, Pl. 2, Fig. 5a-b) and nathus sp. A of VOGES and later Dolymae sp. reillustrated herein in Pl. 1, Fig. 2. A of VOGES are suggested to have been an ancestor of this species (cf. AUSTIN & DERIVATIO NOMINIS : GROESSENS, 1972; GROESSENS, 1976). From Dinant, where this species was found for the first time in Belgium. RANGE : Same as for the genus.
262 Zone unzoned interval unzoned interval
Sample no. ~~Io'°~ oo o .-i '° ro M '° ~ ro .... ~
Gnathodus cuneif ormis 1 1 G. cuneiformis __,.. pseudosemiglaber ï 1- l l 6 26 1 2 l G. pseudoserniglaber 2 8 1 2 4 l 1 5 l 3 - 9 l 36 3 9 5 6 22 8 3 1 l - 4 2 3 l 1 G. homopunctatus 3 3 - l 6 1 G. cf. homopunctatus : 1 - 1 l 1 G. semiglaber 1 G. symrnutatus 1 4 1 G. texanus 2 1 G. typicus M2 l G. sp. juv. 2 17 3 5 1 1 : 1 2 2 2 l 2 3 1 2 1 l 1 Anchignathodus penescitulus = 1 N An. scitulus 1 An. simplicatus ; 1 - 1 l (J.l°' Bispathodus aculeatus aculeatus B. bispathodus Idioprioniodus conjunctus 1 1 Mestognathus beckmanni - ~1: l Polygnathus communis communis 23 P. flabellus l 6 P. inornatus 1 5 l 6 4 l 9 1 1 P. sp. 4 1 = 3 1 l 2 11 spathognathodus 11 rr.acer 4 ~ Gnathodus praebilineatus ~ 1: 1 3 TABLE I - Numerical data on the conodont collection from the "Route de Salet" section. Conodont sample numbers are bed numbers. Zone cuneiformis cuneiformis anchoralis
0 ro 0 ro u N Cf> 0 N r- ro 0 ro .... Cf> r- a> 0 r- ro 0 N r- Cf> ...... no. ro .... Cf> Cf> Cf> Cf> Cf> ...... " ...... N "' "' Sam pie "' "' r- ro ro ro ro Cf> Cf> Cf> "' Cf> "' "' " "' "' "' " "' "'" "' "' "' "' "' "' "' " 0 "' "' " " " "' Gnathodus cuneif ormis - - - - 7 l 3 - 2 5 2 - - - - l - - l 8 4 ------l G. cuneiformis...;. pseudosemiglaber ------2 G. pseudosemiglaber ------2 G. delicatus - - - - l - - 2 2 - l ------2 3 11 l ------l G. punctatus ------2 l ------G. semiglaber ------4 2 l ------4 72 52 1 10 - - --- 5 -- 2 - l G. semiglaber-i>o texanus ------7 - 13 ------l - 3 G. texanus ------2 G. typicus Ml ------2 ------2 - -- G. typicus M2 ------6 ------l G. sp. juv. - - 1 - 2 - 4 7 - l ------3 17 9 2 ï61 : ------1 - l - - 2 Bispathodus aculeatus aculeatus - - -- B. costatus - - - l B. bispathodus - - - - B. stabilis ------42 6 Clydagnathus sp. -- - - l ------Doliognathus dubius ------11 D. latus ------9 - 2 Dollymae bouckaerti ------3 l 3 l 77 l Eotaphrus bultyncki - 5 3 N ------0\ llindeodella segaformis ------l 3 - l - 2 - - - 4 - - 2 l 4 ~ Idioprioniodus conjunctus - - - -- l - - - 11 ------3 - - - 3 4 1 - - l ------l - l Mestognathus beckmanni ------Polygnathus bischoffi ------15 6 12 P. communis cornmunis - 14 4 2 - 6 21 20 10 l ------2 33 5 - - 40 46 45 17 20 - - 2 P. communis carinus - - - 2 l -- 6 6 8 40 6 6 l 15 18 7 17 51 43 ------P. flabellus ------l 4 P. inornatus ------1 ------l 12 5 1 - 13 11 P. longiposticus ------5 ------36 16 2 12 l 36 5 9 11 24 l 2 - - l --- 2 P. mehli ------l P. cf. purus l 3 - l - - l 3 ------P:;, sp. ------2 -- - - 2 2 - - 10 7 Protognathodus cordiformis ------1 ------l 19 12 - 7 30 22 - Pr. praedelicatus - - 2 - - - - l ------2 - - - 3 - Pr. sp. ------l - 5 14 23 - Pseudopolygnathus multistriatus - 3 - - - l - l l - 14 1 4 - - - - l - 4 1 - 2 l - Ps. nudus ------l - - -- l Ps. oxypageus ------1 - 2 - - l l 11 - 4 4 3 2 Ps. pinnatus ------l - 9 - l - l --- 2 -- 3 7 8 15 3 l Scaliognathus praeanchoralis ------l - l - Sc. anchoralis europensis ------8 13 - l - - 1 - 1 12 - 3 2 - 8 Sc. anchoralis fairchildi ------2 - 3 2 2 - -- - - 11 - ."Spathognathodus discret us ------2 11 Sp. Il macer - - - - - 3 - 4 l 3 - - - - - l - -- 39 18 - -- 5 - 2 - 15 - l 1 - 12 4 5 - 1 "Sp. 11 laterigranosus ------l Staurognathus dionantensis ------2 --- - 3 REFERENCES. CONIL, 1\, (1967) - Problèmes du Viséen Inférieur dans le Condroz. Ann. Soc. Géol. AUSTIN, R. L. (1973) - Modification of the Belgique, 90 : B 413-429, 2 Charts, British Avonian conodont zonation Brus sels. and a reappraisal of European Dinantian conodont zonation and correlation. CONIL, R.; AUSTIN, R. L., LYS, M. & RHODES, F.H.T. Ann. Soc. Géol. Belgique, 96 : 523- (1969) - La limite des étages tournai 532, 1 Chart, Liège. sien et viséen au stratotype de l'assi se de Dinant. Bull. Soc. Belge Géol., AUSTIN, R. L. (1976) - Evidence from Great Paléont., Hydrol., 77 : 40-69, 2 Pls., Britain and Ireland concerning West IO Figs., 1 Tab., Brus sels. European Dinantian conodont paleoecolo gy, in BARNES, C. R. (ed.), Conodont CONIL, R. & GROESSENS, E. (1974) - Excursion B, paleoecology. Geol. Assac. Canada in BOUCKAERT, J. & STREEL, M. (eds.), Spec. Paper 15 201-224, 9 Figs., International Symposium on Belgian 3 Tabs., Ottawa. Micropaleontological Limits, guide book : 18-25, Brussels, AUSTIN, R. L. & GROESSENS, E. (1972) - The or1g1n and evolution of the middle Dinantian CONIL, R., GROESSENS, E, & PIRLET, H. (1977) - conodont genera Doliognathus, Dollymae, Nouvelle charte stratigraphique du Scaliognathus and Staurognathus, and Dinantien type de la Belgique, Ann. related forms. Ann, Soc. Géol, Soc. Géol. Nord, 96 : 363-371, 2 Tabs., Belgique, 95 : 229-238, 1 Pl., 2 Figs,, Lille. Liège. CONIL, R. & LYS, M. (1964) - Matériaux pour l'étu BELKA, Z. (1983) - Evolution of the Lower Carboni de micropaléontologique du Dinantien ferous conodont genus Mestognathus. de la Belgique et de la France Acta GeoZ. Polon., 33 : 73-84, 2 Pl., (Avesnois), Algues et Foraminifères. 3 Figs., Warszawa. Mém. Inst. Géol. Univ. Louvain, 23 : 1-290, 42 Pls., 33 Figs., 2 ChartS, BELKA, z. (1984) - Conodont stratigraphy and Louvain. facies of the Lower Carboniferous de~ posits between Olkusz and Sosnowiec, COOPER, C, L. (1949) - Kinderhook micropaleonto The Warsaw Univ., unpublished Ph. D, logy, J. Geol., 56 : 356-366, Chicago. dissertation : 1-137, 29 Pl,, 18 Figs,, 10 Tabs., Warszawa, DRUCE, E. c. (1970) - Lower Carboniferous cono donts from the northern Yarrol Basin, BELKA, z. (1985a) - Lower Carboniferous conodont Queensland, Australian Bur. of Mineral biostratigraphy in the northeastern Res., Geology & Geophysics, Bull., part of the Moravia-Silesia Basin, 108 : 91-114, 4 Pls., 2 Figs., Acta Geol. Polon., 35 ; 33-60, 22 Pl,, Canberra, 6 Figs., Warszawa. GROESSENS, E. (1971) - Les conodontes du Tournai BELKA, Z. (1985b) - Evolution of Lower Carbonife sien supérieur de la Belgique. Serv. rous gnathodis, in ALDRIDGE, R, J,, Géol. de Belgique, Prof. Paper, ± AUSTIN, R. L, & SMITH, M, P. (eds,), 1-29, 2 Pls,, 12 Figs., Brussels. Fourth European Conodont Symposium (ECOS IV) Abstracts : 2-3, Nottingham, GROESSENS, E. (1975) - Preliminary range chart of conodont biozonation in the Belgian BRANSON, E. B. & MEHL, M. G. (1941) - New and Dinantian, in International Symposium little known Carboniferous conodont on Belgian Micropaleontological Limits. genera. Jour. Paleontology, 15 GeoZ. Survey of Belgium, Publ. Q 97-106, 1 Pl., Tulsa, Oklahoma:- 1-193, 49 Pls., Brussels (date of imprint, 1974). BURTON, R. C. (1964) - A prelirninary range chart of Lake Valley Formation (Osage) cono GROESSENS, E. (1976) - Hypothèses concernant donts in the southern Sacramento l'évolution de conodontes utiles Mountains, New Mexico, New Mexico à la biostratigraphie du Dinantien, in Geol. Soc., Fifteenth Field Conf. : International Symposium on Belgian 73-75, 1 Chart, Socorro, New Mexico, Micropaleontological Limits. Geol. Survey of Belgium, Publ. 16 : 1-16, CHAUFF, K. M. (1981) - Multielement conodont 6 Pls., Brussels (date of-rmprint, species from the Osagean (Lower Carbo 1974). niferous) in Midcontinent North America and Texas. Palaeontographica GROESSENS, E., CONIL, R. & LEES, A. (1976) - Abt. A, 175 : 140-169, 4 Pl., 4 Figs. Problèmes relatifs à la limite du 3 Tab 1. , Stuttgart. Tournaisien et du Viséen en Belgique. Bull. Soc. belge Géol., 82 : 17-50, CHAUFF, K. M. (1985) - Phylogeny of the multiele 5 Pls., 12 Figs., BrusseîS (date of ment conodont genera Bactrognathus, imprint, 1973). Do Uognathus and Staurognathus. ,Tow'. Paleontology, 59 : 299-309, 3 Figs., GROESSENS, E. & NOËL, B. (1977) - Etude litho Tulsa, Okl~homa-:- et biostratigraphique du Rocher du Bastion et du Rocher Bayard à Dinant, CHAU~~. K. M, & KLAPFER, G. (1978) - New conodont in International Symposium on Belgian genus ApateUa (Late Devonian), nossi Micropaleontological Limits. Geol. ble homeomorph Bactrognathus (Early Survey of Belgium, Pub. 15 : 1-17, Carboniferous, Osé'.p;ean Series), and 5 Pls., Brussels (date oY-imprint, homeomorphy in conodonts, Geolorica 1974). et Palaeon~ologica, 12 : 151-164, 3 Pls , , Marbur~. 265 PLATE CAPTIONS
P L A T E
All upper view, except as noted.
Figs. 1-2 Staurognathus dionantensis n. sp. 1 - Bed 8/0, x65 2 - Holotype, Bed 8/0, x45.
Fig. 3 Eotaphrus bultyncki (GROESSENS, 1971) Rephotograph of holotype (GROESSENS, 1971; Pl. 1, Figs. 4a, b), Bed 22/92, x75, lateral view.
Figs. 4-6 Dollymae bouakaerti GROESSENS, 1971 4 - Rephotograph of holotype (GROESSENS, 1971; Pl. 1, Figs. 7a, b) Bed 8/0, x55. 5 - Bed 8/0, x60, lower view. 6 - Bed 8/0, x90, Juvenile s.pecimen.
Fig. 7 Saaliognathus praeanahoralis LANE, SANDBERG & ZIEGLER, 1980 Bed 8/3, x!OO.
Figs.8-11 Saaliognathus anahoralis fairahildi LANE & ZIEGLER, 1983 8a, b - Bed 8/lC, x75, lower and upper views. Specimen with larger posteriorly directed cusp. 9-Bed 8/2, xll5. Juvenile specimen. IO - Bed 8/3, xi 30. Juvenile specimen. 11 -Bed 8/IA, x85. Specimen transitional to Saaliognathus anahoralis europensis.
266 PLATE 1
267 P L A T E 2
Fig. Doiiognathus dubius BRANSON & MEHL, 1941. Bed 8/2, xlOO, upper view.. Juvenile specimen.
Fig. 2 Scaiiognathus anchoralis europensis LANE & ZIEGLER, 1983. Bed 8/51, x70, upper view.
Figs.3a,b Mestognathus beckmanni BISCHOFF, 1957 Bed 8/67, x50, upper and lateral views,
Fig. 4 Bispathodus bispathodus ZIEGLER, SANDBERG & AUSTIN, 1974. Bed 8/57, x85, upper view.
Figs 5a,b "Spathognathodus" foterigranosus GEDIK, 1974. Bed 8/2, x95, lateral and upper views.
Figs 6-7 "Spathognathodus" macer (BRANSON & MEHL, 1934). 6 - Bed 8/17, x65, lateral view. 7a,b-Bed 8/56, x60, upper and lateral views.
Fig. 8 - Anchignathodus simplicatus (RHODES, AUSTIN & DRUCE, 1969). Bed 8/68, xl50, lateral view. Juvenile specimen.
Fig. 9 - Pseudopolygnathus pinnatus (VOGES, 1959). Bed 8/lB, x40, upper view.
Figs. 10-12 - Pseudopoiygnathus rrrultistriatus MEHL & THOMAS, 1947. 10 - Bed 22/86, x40, upper view. Morphotype 1. 11 Bed 22/92, x45, upper view. Morphotype 2. 12 Bed 22/92, x50, upper view, Morphotype 2.
Fig. 13 - Pseudopoiygnathus oxypageus LANE, SANBERG & ZIEGLER, 1980. Bed 8/3, x65, upper view. Morphotype 2.
268 PLATE 2
269 P L A T E 3
Figs. 1 - 2 Polygnathus cf. purus VOGES, 1959. l - Bed 22/86, x90, upper view. 2 Bed 22/86, x95, lower view.
Figs. 3 - 4 Polygnathus comnrunis comnrunis BRANSON & MERL, 1934. 3 Bed 8/57, x75, upper view. 4 - Bed 8/57, xl05, lower view. Juvenile specimen. Fig. 5 Polygnathus flabellus (BRANSON & MERL, 1938). Bed 8/51, x60, upper view.
Figs. 6 - 7 Polygnathus bischoffi RHODES, AUSTIN & DRUCE, 1969. 6 - Bed 8/44, x75, upper view. 7 - Bed 8/44, x50, lower view. Advanced form.
Figs. 8 - 10 Polygnathus inornatus E. R. BRANSON, 1934. 8 Bed 8/158, x75, upper view. Specimen transitional to P. flabellus.
9 Bed 8/56, x70, upper view. lOa, b - Bed 8/44, x50, lower and upper views.
Figs. 11 - 15 Polygnathus longiposticus BRANSON & MERL, 1934. 11 - Bed 8/0, x75, lower view. Juvenile specimen with a wide, inverted basal cavity. Compare with large specimen (Pl. 3, Fig. 14a) showing an extremely small basal cavity. 12 - Bed 8/0, x50, lower view. 13 - Bed 8/3, x60, lower view. 14a,b - Bed 8/17, x40, lower and upper views. Large, advanced form with a gerontic, lobe-like extension of the platform ~argin. 15 - Bed 8/17, x40, upper view.
270 PLATE 3
271 P L A T E 4
All up~er views, except Fig. 5. Fig. 1 Protognathodus praedelicatus LANE, SANDBERG & ZIEGLER, 1980. Bed 22/86, x75.
Figs. 2 - 5 Protognathodus cordiformis LANE, SANDBERG & ZIEGLER, 1980. 2 - Bed 8/3, x85. Juvenile specimen. 3 - Bed 8/3, x75. 4 - Bed 8/IC, x85, Juvenile specimen. 5 - Bed 8/2, x85. Margin of the cup partially broken.
Fig. 6 Gnathodus punctatus COOPER, 1939. Bed 22/86, x70.
Figs. 7 -10 Gnathodus delicatus BRANSON & MERL, 1938. 7 - Bed 8/17, x60. Specimen transitional to G. punctatus. 8 - Bed 8/lA, x85. 9 - Bed 8/0, x75. 10 - Bed 22/69, x75.
Figs. 11-12 Gnathodus typicus COOPER, 1938, Morphotype 1. Il - Béd'8/0, x70. 12 - Bed 8/0, x55.
Figs. 13-16 Gnathodus cuneiformis MERL & THOMAS, 1947. 13 - Bed 22/88, x45. 14 - Bed 8/0, x90. 15 - Bed 8/53, x75. Younger morphotype. 16 - Bed 8/!A, x80.
272 PLATE 4 P L A T E 5 l!igs, 1 - 3 Gnathodus cuneiforrnis MERL & THOMAS, 1947. 1 - Bed 8/98, x70. 2 - Bed 8/lA, x55. Specimen transitional to G. delicatus. 3 - Bed 8/IA, x80. Specimen with a peculiar transverse ridge perpendicular to the blade.
Figs. 4 - 9 Gnathodus cunei formfs MERL & THOMAS , 19 4 7 --:;. Gnathodus pseudosemiglaber THOMPSON & FELLOW, 1970. 4 - Bed 8/53, x95. Juvenile specimen. 5 - Bed 8/57, x80. 6 - Bed 8/97, x85. Juvenile specimen. 7 - Bed 8/76, x85. Juvenile specimen. 8 - Bed 8/104, x60 9 - Bed 8/104, x55.
Figs. 10 - 15 Gnathodus pseudosemiglaber THOMPSON & FELLOWS, 1970. 10 - Bed 8/104, x50. li - Bed 8/54, x70. 12 - Bed 8/104, x55. 13 - Bed 8/76, x75. 14 - Bed 8/91, x60. 15 - Bed 8/98, x60.
274 PLATE 5
275 PLATE 6
All upper views. Figs. 1 - 6 Gna,thodus semiglciber (BISCHOFF, 1957). l - Bed 8/lC, x75. 2 - Bed 8/lC, x75, 3 - Bed 8/lC, x60, 4 - Bed 8/lC, x75. 5 - Bed 8/44, x40. 6 - Bed 8/lA, x60.
Figs. 7 - 9 Gna,thodus semiglciber (BISCHOFF, 1957) ~ Gna,thodus texanus ROUNDY, 1926. 7 - Bed 8/lC, x75. 8 - Bed 8/lA, x95. Juvenile specimen. 9 - Bed 8/lC, x70.
Figs. 10 - 11 Gna,thodus texanus ROUNDY, 1926. 10 - Bed 8/lC, x90. Juvenile specimen. 11 - Bed 8/76, x65.
Figs. 12-14 Gna,thodus praebilineatus BELKA, 1985. 12 - Bed 8/163, x45. 13 - Bed 8/190, x45. 14 - Bed 8/190, xlOO. Juvenile specimen.
276 PLATE 6
277 P L A T E 7
All upper views. Figs. 1 - 3 Gnathodus pseudosemiglaher THOMPSON & FELLOWS, 1970. 1 - Bed 8/122, x55. 2 - Bed 8/260, x75. 3 - Bed 8/104, x60.
Figs. 4 -- 5 Gnathodus pseudosemiglaber THOMPSON & FELLOWS, 1970 ~ Gnathodus girtyi HASS, 1953. 4 - Bed 8/268, x70. 5 - Bed 8/263, x95.
Figs. 6 - 7 Gnathodus syrrorrutatus RHODES, AUSTIN & DRUCE, 1969. 6 - Bed 8/83, x80. 7 - Bed 8/211, xl20. Juvenile specimen.
Figs. 8 - 10 Gnathodus cf. homopurwtatus ZIEGLER, 1962. 8 - Bed 8/263, xl02. 9 - Bed 8/216, x 90. 10 - Bed 8/205, x 80.
Figs. 11 - 15 Gnathodus homopunctatus ZIEGLER, 1962. 11 Bed 8/211, xl40. Juvenile specimen. 12 - Bed 8/211, x155. Juvenile specimen with an asymmetrical ornamented cup. 13 - Bed 8/211, x135. Juvenile specimen. 14 - Bed 8/178, xllO. Specimen transitional to G. mermaidus. 15 - Bed 8/183, x 95.
278 PLATE 7
279 llANCE, L. (1985) - Le Moliniacien (Viséen Infé THOMPSON, T. L, & FELLOWS, L. D. (1970) - rieur) du Synclinorium de Dinant Stratigraphy and conodont biostrati depuis la région dinantaise jusqu'à graphy of Kinderhookian and Osagean la vallée de l'Ourthe (Belgique) : (Lower Mississipian) rocks of south biostratigraphie et contexte sédimen western Missouri and adjacent areas. tologique. Université Catholique de Missouri Geol. Survey and Water Res., Louvain, unpublished Ph. D. disserta Rept. Invest., 45 ; 1-263, 8 Pls., tion : 1-196, Louvain. 33 Figs., 1 Tab-;: 25 Charts, Rolla, Missouri. IIASS, W. H. (1959) - Conodonts from the Chappel Limestone of Texas. U. S. Geol. THORNBURY, B. M. (1985) - Conodont biostratigra Survey., Prof. Paper, 294, J : 365- phy of Dinantian rocks from the Cloyne 399, 5 Pls., Washington;-:o:-c. Syncline, Co. Cork. University of Dublin, unpublished M. Sc. thesis : LANE, H. R.; SANDBERG, C. A. & ZIEGLER, W. (1980) - 1-149, 42 Pls., 30 Figs., 5 Tabs., Taxonomy and phylogeny of some Lower Dublin. Carboniferous conodonts and prelimina ry standard post-Siphonodella zonation. VARKER, W. J. & SEVASTOPULO, G. D. (1985) - Geologica et Palaeontologica, 14 : The Carboniferous System : Part 1 - 117-164, 10 Pls., 3 Figs,, 11 Tabs,, Conodonts of the Dinantian Subsystem Marburg. froro Great Britain and Ireland, in HIGGINS, A. C. & AUSTIN, R. L. (eds), LANE, H. R. & ZIEGLER, W. (1983) - Taxonomy and A stratigraphical index of conodonts, phylogeny of Scaliognathus BRANSON & Ellis Horwood Limited : 167-209, MEHL, 1941 (Conodonta, Lower Carboni 5 Pls., 6 Figs., 1 Tab., Chichester. ferous). Senckenbergiana Zethaea, 64 199-225, 4 Pls., 6 Figs., 1 Tab., VOGES, A. (1959) - Conodonten aus dero Unterkarbon Frankfurt am Main. I and II (Gattendorfia- und Pericyclus Stuf e) des Sauerlandes. Palaont. Zeit., LEES, A. (1982) - The paleoenvironmental setting 33: 266-314, 3 Pls., 5 Figs., 1 Tab., and distribution of the Waulsortian Stuttgart. facies of Belgium and southern Britain, in BOLTON, K.; LANE, H. R. & LE MONE, D. V. (eds.), Symp. paleoenvironm, Setting and Ditrib. Waulsorian Facies, El Paso. Geol. Soc. and Univ. Texas at El Paso : 1-16, El Paso/Texas,
LEES, A. (1984) - An introduction and guide to the Waulsortian "reefs" of Belgium, Un{; versité de Louvain : 1-57, 30 Figs,, Louvain-la-Neuve,
LEES, A. & CONIL, R. (1980) - The Waulsortian reefs of Belgium, Geobios, Mém. spécial, 4 : 35-46, 10 Figs,, Lyon. - PAPROTH, E.; CONIL, R.; BLESS, M. J. M.; BOONEN, P.; CARPENTIER, N.; COEN, M.; DELCAMBRE, B.; DEPRIJCK, C.; DEUZON, S.; DREESEN, R.; GROESSENS, E.; llANCE, L. ; HENNEBERT, M. ; HIBO, D. ; IIAHN, G.; IIAHN, R.; HISLAIRE, O.; KASIG, W.; LALOUX, M.; LAUWERS, A.; LEES, A.; LYS, N.; OP DE BEECK, K.; OVERLAU, P.; PIRLET, H.; POTY, E.; RAMSBOTTOM, W.; STREEL, M.; SWENNEN, R.; THOREZ, J.; VANGUESTAINE, M.; VAN STEENWINKEL, M. & VIES LET, J. L. (1983) : Bio- and lithostratigraphic subdivisions of the Dinantian in Belgium, a review. Ann. Soc. Géol. Belgique, 106 : 185-239, l Fig., 5 Tabs., 1 Chart, Liège.
SANDBERG, C.A.; ZIEGLER, W.; LEUTERITZ, K. & BRILL, S. M. (1978) - Phylogeny, speciation and zonation of Siphonondel la (Conodonts, Upper Devonian and Lower Carboniferous). Newsl. Strati gr., !_: 102-120, 2 Figs., Stuttgart.
THOMPSON, T. L. (1967) - Conodont zonation of Lower Osagean rocks (Lower Mississi pian) of southwestern Missouri. Missouri Geol. Survey and Water Res., Rept. Invest. 39 : 1-88, 6 Pls., 6 Manuscript received on Figs., 6 Tabs.-;-Rolla, Missouri. March, 18 th., 1986. 280