GEOLOGICA CARPATHICA, JUNE 2005, 56, 3, 223236
Upper Devonian (Upper FrasnianLower Famennian)
conodont biostratigraphy of the Ayineburnu Formation
(Istanbul Zone, NW Turkey)
Department of Geological Engineering, Karadeniz Technical University, 61080 Trabzon, Turkey;
(Manuscript received May 18, 2004; accepted in revised form September 29, 2004)
Abstract: Conodont faunas, which generally represent the pelagic palmatolepid-polygnathid or palmatolepid biofacies
and correlate well with the standard Upper Devonian conodont zonation, were obtained from an incomplete stratigraphic
section of the Ayineburnu Formation, Istanbul Zone, Turkey. Three of the upper Frasnian standard conodont zones
extending from the Lower rhenana Zone into the linguiformis Zone, and six of the lower Famennian standard conodont
zones extending from the Middle triangularis Zone into the Uppermost crepida Zone have been recognized with these
conodont faunas. Zonal indices for the Lower triangularis Zone and the Frasnian/Famennian (F/F) boundary are not
present. Strata assigned to the linguiformis Zone are overlain by a one meter unsampled interval. The next sample
represents the Middle triangularis Zone, the conodont faunas of which are densely covered by matrix, suggesting a
reworking. Also, the presence of the Lower and Middle crepida Zones is based on the recognition of only the lower and
upper limits, respectively. The boundary between these zones could not be determined due to the absence of the zonally
Key words: Upper Devonian, Frasnian, Famennian, Turkey, biostratigraphy, conodonts.
The Pontides, one of the main tectonic units of Turkey, com-
prise the Strandja, Sakarya and Istanbul Zones with different
stratigraphic and tectonic developments (Fig. 1). The Turkish
part of the Strandja Zone consists of a basement of felsic
gneiss and migmatite, intruded by Hercynian granitic plutons,
which is unconformably overlain by the Triassic continental to
shallow-marine clastics and carbonates. The basement of the
Sakarya Zone comprises two tectonic assemblages that were
juxtaposed during the Triassic: a lower assemblage of Paleo-
zoic granitic and metamorphic rocks, and an upper assemblage
of accretionsubduction units of the Paleo-Tethys, termed the
Karakaya Complex. A Mesozoic cover with several major un-
conformities, rather different from the Mesozoic stratigraphy
of the Istanbul Zone, unconformably overlies this basement
(Okay 1987; Okay et al. 1994, 1996). The Istanbul Zone locat-
ed along the western Black Sea coast consists of a continuous
well-developed generally transgressive sedimentary sequence
extending from the Ordovician into the Carboniferous. This
Paleozoic sequence was folded and possibly thrust-faulted
during the Late Carboniferous-Permian Hercynian Orogeny
and was then unconformably overlain by Triassic and younger
sedimentary rocks, particularly well developed east of Istanbul
(Gedik 1975). The Paleozoic stratigraphy of the Istanbul Zone
is unique in northwestern Turkey, where in situ pre-Permian
sedimentary sequences are not known, and it bears close re-
semblance to the Moesian Platform (Okay et al. 1994, 1996)
and the Brunovistulian Terrane of Central Europe (Kalvoda et
al. 2003). According to Okay et al. (1994, 1996), the paleo-lat-
itudes for Paleozoic and Triassic rocks of the Istanbul Zone
are compatible with a location along the southern margin of
Laurasia. To explain these features they suggested that the
Istanbul Zone rifted from the southern margin of Laurasia dur-
ing the Late Cretaceous. Yanev (1993), however, proposed
that the Moesian superterrane has a Gondwanic or peri-
Gondwanic origin according to paleoclimatic and paleomag-
netic evidence as well as sedimentologic features.
The stratigraphic and sedimentologic characteristics of the
Paleozoic sedimentary sequence around IstanbulGebze
(Kocaeli) of the Istanbul Zone are different from that of the
Eastern part of Gebze (Kocaeli). For example, the Upper De-
vonian is characterized, around IstanbulGebze (Kocaeli), by
the sedimentary rocks of the pelagic facies. However, it is rep-
resented, in the East of Gebze, by the shelf facies. Therefore,
Göncüoûlu & Kozur (1998) and Kozur & Göncüoûlu (1999)
divided the Paleozoic of Istanbul into two terranes with dif-
ferent Paleozoic-Mesozoic histories: the Istanbul Terrane (Pa-
leozoic-Mesozoic sequence around IstanbulGebze) and the
Zonguldak Terrane (Çamdaû, Zonguldak, Amasra and Safran-
bolu regions). According to them, both terranes were north of
peri-Gondwana during the early Paleozoic.
Although the Upper Devonian rocks are present in the Istanbul
Zone of the Pontides, in the Taurides, and in the Border Folds,
the rocks that represent pelagic facies are known only from the
Istanbul Zone of the Pontides (Fig. 1). These rocks, belonging
to the Ayineburnu Formation (Kaya 1973; Önalan 1982,
1988), are exposed in small and discrete outcrops due to the
intense tectonic deformation. Some suitable sections are ex-
posed at the Tuzla Peninsula, located approximately 30 km
southeast of Istanbul, northwestern Turkey (Fig. 1). Previous-
ly, Çapkônoûlu (1997, 2000) investigated some Upper Devo-
nian conodont faunas from the Büyükada (Istanbul) and Gebze
(Kocaeli) areas. The subject of the present paper is the descrip-
tion and biostratigraphic analysis of the conodont faunas ob-
tained from an incomplete section of the Ayineburnu Forma-
tion exposed along the northern shore of the Tuzla Peninsula
(Fig. 1). The first examinations of samples recovered from this
section indicated evidence of the F/F boundary. However, the
boundary interval corresponds to an unsampled part of the
section due to lack of outcrop on the surface. A second at-
tempt to sample the boundary interval proved impossible. The
locality had been filled by the municipality to protect the area
from sea waves.
Lithology and stratigraphy
Paleozoic rocks of the Istanbul Zone, which is generally ac-
cepted as a Hercynian fragment rifted from the southern mar-
Fig. 1. Tectonic map of Turkey (Okay et al. 1994, 1996) and location map of the studied stratigraphic section. Explanations: SZ Strandja
Zone, SKZ Sakarya Zone, IZ Istanbul Zone, NAF North Anatolian Fault, BFZ Bornova Flysch Zone, EAF East Anatolian
Fault, BSZ Bitlis Suture Zone.
gin of Laurasia during the Late Cretaceous (Okay et al. 1996),
belong to an interval extending from the Ordovician into the
Lower Carboniferous. The development during the Ordovi-
cianearly Visean reflects the transgressive, pre-flysch sedi-
mentation of an Atlantic-type passive continental margin,
turned into a Pacific-type active continental margin after the
early Visean (Okay et al. 1994, 1996; Seymen 1995). The Up-
per Devonian Ayineburnu Formation studied herein is the part
of this Paleozoic sequence. The Ayineburnu was first pro-
posed by Kaya (1973) for exposures in Büyükada, Istanbul,
where it is incomplete. It has been studied under different
names, but first naming appropriate to stratigraphic rules was
made by Kaya (1973). These strata were originally described
by Haas (1968) as the Denizli beds of the Tuzla Formation
from the Denizliköyü area, Kocaeli. Subsequently, Kaya
(1973) introduced the name Ayineburnu for the outcrops of
this unit in Büyükada, and assigned it to the Büyükada Forma-
tion to include the Bostancô, Yörükali, and Ayineburnu Mem-
bers, respectively. Önalan (1982, 1988) incorporated these
members into the Tuzla Formation, retaining the same names
UPPER DEVONIAN CONODONT BIOSTRATIGRAPHY OF THE ISTANBUL ZONE (NW TURKEY) 225
Fig. 2. Stratigraphic section showing lithology, sample locations, and standard conodont zones.
and boundaries. In this study the terminology of Kaya (1973)
and Önalan (1982, 1988) has been followed due to their well-
known and common use. However, based on their lithostrati-
graphic features, all members have been raised herein to for-
mation rank. Detailed descriptions of these units are given in
Kaya (1973) and Önalan (1982, 1988). In this study the Ayine-
burnu Formation is used as equivalent of the Ayineburnu
Member in previous papers (Çapkônoûlu 1997, 2000).
Numerous exposures of the Ayineburnu Formation are
faulted or covered by soil as indicated in previous papers
(Çapkônoûlu 1997, 2000), therefore, accurate estimates of its
thickness are currently impossible. The section studied is situ-
ated on the northern shore of the Tuzla Peninsula (topographic
sheet 1/25000, Bursa G22-b4, approximately 30 km SE of
Istanbul, 500 m NW of Köºk Tepe, and 15 m N of the Tennis
and Sea Club of Tuzla (Fig. 1)). The section is about 45
meters thick (Fig. 2), and biostratigraphic analysis indicates
that the whole sequence is overturned, dipping about 70° to
the southwest. Soil and beach sediments cover the lower con-
tact; the upper contact is fault-bound.
The lithology consists of bluish light grey to grey, nodular
and bedded limestones, mainly mudstone and lesser wacke-
stone, with yellowish light brown to beige shale partings, as
well as black chert nodules and interbeds that become more
prevalent in the upper parts of the sequence. The matrix is re-
crystallized in some samples. The limestones contain locally
abundant ostracods, radiolarians, and rare brachiopods, as
well as echinoderm and other fossil debris in a matrix of lime
mud, where their abundance is less than 10 percent by vol-
ume. Tentaculites, generally restricted to the Frasnian sam-
ples, are abundant at certain levels, but are less common than
ostracods. In acid residue, common ostracods, few tentaculites
(homoctenids), rare brachiopods, and rare sponges were ob-
tained along with the conodonts. Ostracods belong to the Thu-
ringian ecotype, dominated by smooth and thin-shelled, often
delicately to strongly spinose forms, which is generally con-
sidered to be indicative of low-energy environments, indepen-
dent of paleo-depth and shoreline (Becker et al. 2003). Both
sedimentary features (Önalan 1982, 1988) and conodont bio-
facies of the studied stratigraphic section suggest deposition in
a basin slope setting.
57 of 63 limestone samples collected from the Ayineburnu
Formation produced Late Devonian (late Frasnian and early Fa-
mennian) conodont faunas (Fig. 2; Tables 1 and 2). They gener-
ally represent the pelagic palmatolepid-polygnathid or palma-
tolepid biofacies correlating well with the standard Upper
Devonian conodont zonation first proposed by Ziegler (1962)
and updated by Ziegler & Sandberg (1990). Three of the upper
Frasnian conodont zones extending from the Lower rhenana
Zone into the linguiformis Zone, and six of the lower Famenni-
an conodont zones extending from the Middle triangularis
Zone into the Uppermost crepida Zone have been recognized.
Lower rhenana Zone The conodont faunas of the sam-
ples 76 and 75 are nondiagnostic, and have been conditionally
assigned to the Lower rhenana Zone. Overlying sample 74 is
within the Upper rhenana Zone because it contains Icriodus
alternatus alternatus, which first appears at or just after the
start of this zone (Ziegler & Sandberg 1990, p. 21) (Table1).
Table 1: Distribution and abundance of Pa elements of conodont taxa in the studied stratigraphic section. See Fig. 2 for sample intervals.
L. rh. Lower rhenana, ling. linguiformis, M. tr. Middle triangularis, L.-M. cr. Lower and Middle crepida, Pa. Pal-
matolepis, Po. Polygnathus, Ic. Icriodus, Pe. Pelekysgnathus.
Sample number (Tuzla)
76 75 74 73 72 71 70 69 68 67 66 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49
Sample weight (kg)
.40 .70 .65 .80 .80 .90 .60 .60 .80 .70 .70 .50 .70 .90 .70 .50 .55 .80 .85 .40 .75 .95 .90 .50 .75 1.2 75
12 10 75
20 285 18 22
3 29 53
Pa. sp. A
45 22 14
Pa. sp. C
Pa. sp. B
Ic. alternatus alternatus
Pa. sp. E
Pa. cf. Pa. hassi
Pa. sp. D
Ic. alternatus helmsi
Pa. delicatula delicatula
Pa. delicatula platys
Pa. minuta minuta
9 52 48
1 10 10 55 18 18 41
Pa. aff. Pa. wolskae
Po. glaber glaber
Pa. aff. P. adamantae
UPPER DEVONIAN CONODONT BIOSTRATIGRAPHY OF THE ISTANBUL ZONE (NW TURKEY) 227
Upper rhenana Zone The base of this zone is defined
by the first occurrence of Palmatolepis rhenana rhenana by
Ziegler & Sandberg (1990). This species was not recognized
in the present study, therefore the recognition of the lower
boundary is based on the presence of Icriodus alternatus al-
ternatus in sample 74 (Table 1). The lowest occurrence of
Palmatolepis linguiformis in sample 64 defines the upper
Furthermore the lowest occurrence of Palmatolepis bogar-
tensis in sample 72 defines the base of the Montagne Noire
(MN) Zone 13 (Klapper 1989; Klapper & Becker 1999), and
all strata containing the range of Palmatolepis bogartensis
(samples 7263) are within this zone (Fig. 2). The lower sam-
ples (7673) can be tentatively assigned to the MN Zone 12
due to the absence of the defining taxa.
Linguiformis Zone The base is determined by the first
appearance of Palmatolepis linguiformis in sample 64 (Ta-
ble 1). Sample 63 with Palmatolepis linguiformis is also with-
in this zone. The upper boundary is not detectable due to the
lack of any taxa defining the base of the overlying Lower tri-
Lower triangularis Zone The Lower triangularis Zone
is not documented in the studied stratigraphic section. The
base of this zone, corresponding to the F/F boundary, is recog-
nized by the first occurrence of Palmatolepis triangularis that
is stratigraphically above the faunas dominated by late Fras-
nian species of Palmatolepis, Ancyrognathus, and Ancyrodel-
la (Klapper et al. 1994). In the studied stratigraphic section,
Palmatolepis triangularis first occurs together with Palmatol-
epis delicatula platys in sample 62, characteristic of the Mid-
dle triangularis Zone (Table 1). If the Lower triangularis
Zone is not missing due to faulting, non-deposition or erosion,
it must be restricted to the interval between samples 63 and 62
Middle triangularis Zone This zone is defined by the
entry of Palmatolepis delicatula platys in sample 62, but its
lower boundary may extend below this sample. The appear-
ance of Palmatolepis minuta minuta, defining the upper
boundary, is in sample 60 (Table 1).
Upper triangularis Zone This zone starts with the first
occurrence of Palmatolepis minuta minuta in sample 60, and
extends to the first occurrences of Palmatolepis quadrantino-
dosalobata and Pelekysgnathus inclinatus in sample 50 (Ta-
Lower and Middle crepida Zones The base of the Low-
er crepida Zone has been defined by first occurrence of Pal-
matolepis crepida by Ziegler & Sandberg (1990). In the stud-
ied stratigraphic section, this species first occurs in sample 48.
However, sample 50 contains the co-occurrence of Palmatole-
pis quadrantinodosalobata and Pelekysgnathus inclinatus,
both of which first appeared at or near the start of the Lower
crepida Zone (Ziegler & Sandberg 1990, p. 23; Schülke 1995,
p. 28), and this occurrence indicates to the base of this zone
for sample 50. The interval between the lowest occurrences of
Palmatolepis quadrantinodosalobata with Pelekysgnathus in-
clinatus, and Palmatolepis glabra unca Sannemann (= Palma-
tolepis glabra prima) represents the Lower and Middle crepi-
da Zones, and includes samples from 50 to 34 of the studied
stratigraphic section (Tables 1, 2). The zonal indices for the
boundary between these two zones are absent.
Table 2: Distribution and abundance of Pa elements of conodont taxa in the studied stratigraphic section. See Fig. 2 for sample intervals.
Pa. Palmatolepis, Po. Polygnathus, Pe. Pelekysgnathus, Me. Mehlina, Ic. Icriodus.
Lower and Middle crepida
Sample number (Tuzla)
48 47 46 45 42 40 39 38 36 35 34 33 32 31 30 29 28 27 26 25 25a 24 23 22 21 20 19 18 16 15
Sample weight (kg)
.75 .60 1.0 1.4 .90 .50 .80 .50 .85 1.0 .65 1.2 .80 .60 1.33 .90 .65 .65 .95 .70 .75 .80 .80 1.4 .50 .90 .80 1.2 .90 .85
Pa. minuta minuta
13 1 5 4 2 10 34 3
1 3 2 8 6 50 18 8 19 24 8 32 7 1 20 7 15 4 4 2 7
1 1 1
2 3 7 2 1 1 11 4 10 7 3 10 2 2
2 1 1
4 4 1? 2
4 1 2
6 4 3 2 3 3 5 1
3 2 1
1 1? 3 4 8 3
3 16 2 4 3 7 2 4 8 1 2
Po. glaber glaber
2 4 4 4 4 1
Pa. glabra unca
3 2 12 1 4 11 5 8 34 13 5 20 8 28 5 6 1 16
Pa. aff. Pa. minuta subtilis
1? 5 3 13 7 10 10 2
Pa. aff. Pa. adamantea
2 2 1
Pa. quadrantinodosalobata M1
1 4 2 1 2
2 3 1
Pa. gracilis gracilis
2 2 6 1
Po. nodocostatus nodocostatus
Pa. glabra pectinata M1
2 1 2
Pa. glabra pectinata
Pa. glabra acuta
Upper crepida Zone The first occurrence of Palmatole-
pis glabra unca, the defining taxon for the base of the Upper
crepida Zone, is in sample 34 (Table 2). The upper boundary
forming the base of the overlying Uppermost crepida Zone is
based on the lowest occurrence of Palmatolepis glabra pecti-
nata Morphotype 1 in sample 24.
Uppermost crepida Zone The first occurrence of Palma-
tolepis glabra pectinata Morphotype 1 in sample 24 defines the
base of the Uppermost crepida Zone. Higher samples (2315)
have been assigned to this zone due to lack of the diagnostic
taxa representing the Lower rhomboidea Zone (Table 2).
The sequence of conodont species in the studied stratigraphic
section of the Ayineburnu Formation and their correlations with
the standard Upper Devonian conodont zonation of Ziegler &
Sandberg (1990) are given in Tables 1 and 2. Conodonts be-
long to Icriodontidae, Palmatolepididae, Polygnathidae, and
Spathognathodontidae families, and the most abundant con-
odont genus is Palmatolepis. All taxa are illustrated in
Figs. 36, and some are discussed below. The multielement
notation and suprageneric classification used are those of
Sweet (1988). Figured specimens and faunal slides are depos-
ited at Department of Geological Engineering, Karadeniz
Technical University, Trabzon, Turkey.
Family: Palmatolepididae Sweet, 1988
Genus: Palmatolepis Ulrich et Bassler, 1926
Type species: Palmatolepis perlobata Ulrich et Bassler, 1926
Palmatolepis aff. P. adamantea Metzger, 1994
Remarks: The diamond-shaped platform outline, the
broad semicircular parapet on inner side, the finely shagreen
upper surface ornamentation, and the weakly developed poste-
rior carina have been accepted as the most distinguishing fea-
tures of the Pa element of Palmatolepis adamantea by
Metzger (1994). Lack of a broad semicircular parapet on the
anterior inner side distinguishes this species from the latter.
Palmatolepis aff. P. adamantea, furthermore, has a longer
free blade. In the Pa element of Palmatolepis adamantea, the
anterior margin of the outer platform extends near to the ante-
rior end of the free blade in contrast with Palmatolepis aff. P.
Palmatolepis delicatula Branson et Mehl, 1934
Palmatolepis delicatula platys Ziegler et Sandberg, 1990
1990 Palmatolepis delicatula platys Ziegler et Sandberg, p. 6768,
Pl. 17, Figs. 47 (synonymy)
Remarks: Palmatolepis delicatula platys is distinguished
from Palmatolepis delicatula delicatula by having a more or
less convex anterior outer platform margin, a concave posteri-
or outer platform margin, and a more rounded outer lobe of Pa
element. Palmatolepis delicatula delicatula has a straight or
slightly concave outer anterior platform margin, and a more
pointed outer lobe.
Palmatolepis ederi Ziegler et Sandberg, 1990
1990 Palmatolepis ederi Ziegler et Sandberg, p. 6263, Pl. 9, Figs. 17;
Pl. 10, Figs. 610 (synonymy)
Remarks: The Pa element of this species can be confused
with that of Palmatolepis eureka with a similar platform out-
line. They can be easily distinguished by the location on the
blade-carina line of the central node. Although the central
node is in the same line with the anterior and posterior carinas
in Palmatolepis ederi, it exhibits a prominent lateral-offset
due to the sharply deflection inwardly of the posterior carina
in Palmatolepis eureka, and forms a sharp corner between the
anterior and posterior carinas.
Palmatolepis hassi Müller et Müller, 1957
1957 Palmatolepis (Manticolepis) hassi Müller et Müller, p. 1102
1103, Pl. 139, Fig. 2; Pl. 140, Figs. 24 (Fig. 4 = holotype)
Remarks: The specimens conform to description of
Klapper & Foster (1993).
Palmatolepis jamieae Ziegler et Sandberg, 1990
1990 Palmatolepis jamieae Ziegler et Sandberg, p. 5051, Pl. 6,
Figs. 110; Pl. 11, Figs. 46 (synonymy)
Remarks: Ziegler & Sandberg (1990) indicated two mor-
photypes, one with well-differentiated lobe and one with a
poorly differentiated lobe of Palmatolepis jamieae. The
present Pa elements generally belong to the second morpho-
The Pa elements with a poorly differentiated lobe of this
species can be confused to those of Palmatolepis juntianensis.
However, the latter is distinguished by having a narrow and
long anterior platform, and a characteristically straight posteri-
or margin of the outer platform.
Palmatolepis lobicornis Schülke, 1995
1995 Palmatolepis lobicornis Schülke, p. 4041, Pl. 4, Figs. 117
1999 Palmatolepis lobicornis Schülke Schülke,p. 4041, Pl. 5,
2004 Palmatolepis lobicornis Schülke Klapper, Uyeno, Armstrong et
Telford, p. 379, Fig. 7.30 (synonymy)
Remarks: This species has been accepted as subspecies
of Palmatolepis subperlobata by Ovnatanova (1976) and
named as Palmatolepis subperlobata helmsi. Schülke (1995)
assigned it to Palmatolepis lobicornis and Schülke (1999)
UPPER DEVONIAN CONODONT BIOSTRATIGRAPHY OF THE ISTANBUL ZONE (NW TURKEY) 229
Fig. 3. Upper Devonian conodonts from the Tuzla Peninsula, the Istanbul Zone, NW Turkey. All upper views of Pa elements unless other-
wise indicated. 1 Palmatolepis glabra pectinata Ziegler, 1962, Morphotype 1; Tuzla 20. 2 Palmatolepis glabra pectinata Ziegler,
1962; Tuzla 22. 3 Palmatolepis falcata (Helms, 1959); Tuzla 24. 45 Palmatolepis glabra unca Sannemann, 1955b (= Palmatolepis
glabra prima Ziegler et Huddle, 1969); 4 Tuzla 25a; 5 Tuzla 25a. 6 Palmatolepis glabra acuta Helms, 1963; Tuzla 15. 7 Palma-
tolepis minuta minuta Branson et Mehl, 1934, Tuzla 25a. 89 Palmatolepis loba Helms, 1963; 8 Tuzla 40; 9 Tuzla 25a. 1011
Palmatolepis regularis Cooper, 1931; 10 Tuzla 24; 11 Tuzla 38. 1213 Palmatolepis clarki Ziegler, 1962; 12 Tuzla 57; 13
Tuzla 51. 1415 Palmatolepis delicatula delicatula Branson et Mehl, 1934; 14 Tuzla 51; 15 Tuzla 62. 1617 Palmatolepis deli-
catula platys Ziegler et Sandberg, 1990; 16 Tuzla 62; 17 Tuzla 53. 1819 Palmatolepis protorhomboidea Sandberg et Ziegler,
1973; 18 Tuzla 53; 19 Tuzla 62. 20 Palmatolepis quadrantinodosalobata Sannemann, 1955a; Tuzla 32. 21 Palmatolepis
quadrantinodosalobata Sannemann, 1955a, Morphotype 1; Tuzla 22. 2223 Palmatolepis aff. P. adamantea Metzger, 1994; 22 Tuzla 29;
23 Tuzla 28. 2425 Palmatolepis subgracilis Bischoff, 1956; upper and lateral views of same specimen; Tuzla 19. Scale bar = 0.2 mm.
proposed a multielement reconstruction for the species. As in-
dicated by Klapper et al. (2004), her name is junior homony-
my of Palmatolepis helmsi Ziegler, and therefore, the valid
name is Palmatolepis lobicornis Schülke.
Platform outline of Pa element of Palmatolepis subperloba-
ta is similar to that of Palmatolepis triangularis, differing
only in ornamentation. Pa elements of present species have a
longer outer lobe and generally straight posterior outer plat-
Palmatolepis aff. P. minuta subtilis Khalymbadzha et
Remarks: The Pa element of Palmatolepis minuta subti-
lis is characterized by a narrow and long posterior platform
with a sharply pointed posterior tip. The present Pa elements
have a shorter and wider posterior platform with a blunt pos-
terior tip distinguishing them from those of Palmatolepis
Palmatolepis mucronata Klapper, Kuzmin et Ovnatanova,
1996 Palmatolepis mucronata Klapper, Kuzmin et Ovnatanova, p. 147,
Figs. 7.97.13 (synonymy)
Remarks: Palmatolepis mucronata is similar to Palma-
tolepis rhenana in general outline of the Pa element but differs
by having a straight and extremely thin posterior carina that is
directed sharply inward. The present Pa elements are closer to
Palmatolepis mucronata by having a weakly developed poste-
rior carina. The Pa elements of Palmatolepis rhenana have a
well-developed posterior carina with large nodes.
Palmatolepis winchelli (= P. subrecta) (Stauffer, 1938)
Figs. 5.19, 6.11
1938 Bryantodus winchelli Stauffer, p. 423, Pl. 48, Fig. 33
1993 Palmatolepis winchelli (Stauffer) Klapper et Foster,
p. 24, 26, 31, Figs. 13.113.2, 18.118.8, 18.1018.11, 19.6
19.12, 20.1220.24 (see synonymy)
Remarks: Specimens assigned to this species are similar
to Palmatolepis gigas in general outline and ornamentation of
the Pa element but are characterized by a low unfortified ros-
tral area on the outer anterior platform and a weak marginal
fortification on the inner anterior platform as indicated by Zie-
gler & Sandberg (1990). Palmatolepis gigas has a rostrum that
is strongly fortified on both sides of the anterior platform.
Palmatolepis sp. A
Diagnosis: Pa element has a relatively narrow and long
platform with a smooth upper surface, a weak lobe that is de-
marcated by deep anterior and weak posterior sinuses and di-
rected anteriorly, and a pointed and downflexed posterior ter-
mination. Slightly sigmoidal carina does not extend to the
posterior tip of the platform. Posterior outer margin is nearly
straight or has very shallow sinus just posterior of lobe, fol-
lowed by a slightly convex curve to posterior tip.
Remarks: The Pa element of Palmatolepis ljaschenkoae
differs by having a wide, strongly convex posterior outer plat-
form, a narrow anterior platform, and a well-developed outer
lobe, which is demarcated by deep anterior and posterior si-
nuses. The anterior margin of the lobe is about at a right angle
to carina. Posterior carina is deflected strongly laterally.
One of the specimens assigned to Palmatolepis praetrian-
gularis by Savage & Yudina (2000: Pl. 1, Fig. 8) probably be-
long to this species.
Palmatolepis sp. B
Diagnosis: Pa element has a more or less triangular plat-
form with a short outer lobe directed laterally, and a moderate-
ly sigmoidal carina. The anterior margin of the outer platform
varies from nearly straight in small specimens to slightly con-
cave in larger specimens. The posterior margin of the outer
platform is straight, or has a shallow sinus just posterior of
lobe, followed by prominent convex curve to posterior tip.
Platform is smooth or bears a few random nodes in large spec-
imens. The posterior end is deflected downward.
Remarks: The Pa element of Palmatolepis sp. A has a
narrower platform with a weak outer lobe directed anteriorly,
and a sharply pointed posterior termination.
Palmatolepis sp. C
Diagnosis: The Pa element of the large specimens has a
triangular platform with strongly nodose margins and an out-
er lobe that is demarcated by shallow anterior and posterior
sinuses. The anterior and posterior margins of the outer plat-
form are slightly convex. Inner platform margin is a convex
Remarks: Specimens assigned to this species are similar
to Palmatolepis winchelli in the ornamentation of the Pa ele-
ment but differ in the platform outline. Pa element of Palma-
tolepis subrecta youngquisti Savage with similar platform or-
namentation has a longer free blade, and a longer platform
with a sharply pointed outer lobe.
The Pa elements of Palmatolepis sp. C are rather similar to
those of Palmatolepis clarki. They can be distinguished only
by their inner platform outlines. In the Pa elements of Palma-
tolepis clarki, the inner platform outline is a convex curve that
is the widest in the central-node position. The widest part of
the inner platform in Palmatolepis sp. C has a more anteriorly
Palmatolepis sp. D
Diagnosis: Pa element has an oval platform. Triangular
outer platform has slightly convex anterior and posterior mar-
gins. Outer lobe is not developed. Posterior end is rounded. In-
ner platform margin is a convex curve extending from anterior
UPPER DEVONIAN CONODONT BIOSTRATIGRAPHY OF THE ISTANBUL ZONE (NW TURKEY) 231
Fig. 4. Upper Devonian conodonts from the Tuzla Peninsula, the Istanbul Zone, NW Turkey. All upper views of Pa elements unless other-
wise indicated. 1 Polygnathus glaber glaber Ulrich et Bassler, 1926; Tuzla 24. 23 Polygnathus lodinensis Pölsler, 1969; 2 Tuzla 75;
3 Tuzla 73. 4 Polygnathus decorosus Stauffer, 1938; Tuzla 67. 56 Polygnathus brevilaminus Branson et Mehl, 1934; 5 Lateral
view, Tuzla 30; 6 Tuzla 72. 7 Polygnathus semicostatus Branson et Mehl, 1934; Tuzla 15. 8 Polygnathus procerus Sannemann,
1955b; Lateral view; Tuzla 48. 9 Ancyrodella nodosa Ulrich et Bassler, 1926; Tuzla 74. 10 Ancyrodella ioides Ziegler, 1958; Tuzla 74.
11 Ancyrognathus amana Müller et Müller, 1957; Tuzla 72. 12 Polylophodonta sp.; Tuzla 21. 13 Polygnathus nodocostatus
nodocostatus Branson et Mehl, 1934; Tuzla 25a. 1418 Palmatolepis lobicornis Schülke, 1995; 14 Tuzla 22; 15 Tuzla 51; 16
Tuzla 32; 17 Tuzla 20; 18 Tuzla 26. 19 Palmatolepis aff. P. wolskae Ovnatanova, 1969; Tuzla 57. 2021 Palmatolepis crepida
Sannemann, 1955b; 20 Tuzla 25a; 21 Tuzla 48. 22 Palmatolepis perlobata schindewolfi Müller, 1956; Tuzla 30. 2324 Palma-
tolepis tenuipunctata Sannemann, 1955b; 23 Tuzla 50; 24 Tuzla 31. Scale bar = 0.2 mm.
Fig. 5. Upper Devonian conodonts from the Tuzla Peninsula, the Istanbul Zone, NW Turkey. All upper views of Pa elements unless other-
wise indicated. 12 Palmatolepis triangularis Sannemann, 1955a; 1 Tuzla 62; 2 Tuzla 51. 3 Palmatolepis bogartensis (= P. ro-
tunda) (Stauffer, 1938); Tuzla 72. 4 Palmatolepis linguiformis Müller, 1956; Tuzla 64. 57 Palmatolepis aff. P. minuta subtilis
Khalymbadzha et Chernysheva, 1978; 5 Tuzla 27; 6 Tuzla 28; 7 Tuzla 28. 89 Palmatolepis mucronata Klapper, Kuzmin et
Ovnatanova, 1996; 8 Tuzla 72; 9 Tuzla 69. 10 Palmatolepis eureka Ziegler et Sandberg, 1990; Tuzla 67. 11 Palmatolepis ederi
Ziegler et Sandberg, 1990; Tuzla 75. 1213 Palmatolepis hassi Müller et Müller, 1957; 12 Tuzla 74; 13 Tuzla 74. 14 Palmatole-
pis gigas Miller et Youngquist, 1947; Tuzla 63. 1516 Palmatolepis jamieae Ziegler et Sandberg, 1990; 15 Tuzla 69; 16 Tuzla 69.
1718 Palmatolepis juntianensis Han, 1987; 17 Tuzla 64; 18 Tuzla 73. 19 Palmatolepis winchelli (=P. subrecta) (Stauffer,
1938); Tuzla 63. Scale bar = 0.25 mm for figures 1, 3, 13, and 0.2 mm for others.
UPPER DEVONIAN CONODONT BIOSTRATIGRAPHY OF THE ISTANBUL ZONE (NW TURKEY) 233
Fig. 6. Upper Devonian conodonts from the Tuzla Peninsula, the Istanbul Zone, NW Turkey. All upper views of Pa elements unless otherwise
indicated. 13 Palmatolepis sp. C; 1 Tuzla 75; 2 Tuzla 75; 3 Tuzla 68. 45 Palmatolepis sp. A; 4 Tuzla 74; 5 Tuzla 75. 6
10 Palmatolepis sp. B; 6 Tuzla 64; 7 Tuzla 74; 8 Tuzla 72; 9 Tuzla 75; 10 Tuzla 72. 11 Palmatolepis winchelli (= P.
subrecta) (Stauffer, 1938); Tuzla 68. 12 Palmatolepis sp. E; Tuzla 64. 13 Palmatolepis sp. D; Tuzla 64. 1415 Palmatolepis cf. P.
hassi Müller et Müller, 1957; 14 Tuzla 69; 15 Tuzla 68. 1617 Palmatolepis subperlobata Branson et Mehl, 1934; 16 Tuzla 60;
17 Tuzla 50. 18 Icriodus cornutus Sannemann, 1955b; Lateral view; Tuzla 24. 1920 Icriodus alternatus alternatus Branson et
Mehl, 1934; 19 Tuzla 57; 20 Tuzla 57. 21 Icriodus alternatus helmsi Sandberg et Dreesen, 1984; Tuzla 57. 22 Pelekysgnathus
inclinatus Thomas, 1949; Lateral view; Tuzla 50. 23 Pelekysgnathus planus Sannemann, 1955b; Lateral view; Tuzla 30. 24 Mehlina
gradata Youngquist, 1945; Lateral view; Tuzla 21. 2526 Palmatolepis gracilis gracilis Branson et Mehl, 1934; 25 Inner lateral view,
Tuzla 21; 26 Inner lateral view, Tuzla 20. Scale bar = 0.2 mm.
to posterior tip. Free blade is well developed. Carina is slightly
Remarks: The Pa elements of Palmatolepis ederi and
Palmatolepis eureka differ by having a strongly sigmoidal ca-
rina, a more ovate platform, and a short free blade. The present
Pa elements have a longer free blade.
Palmatolepis sp. E
Diagnosis: A nearly circular platform with a smooth up-
per surface, a moderately long and straight free blade, and a
strongly sigmoidal carina are distinctive features of the Pa ele-
ment. Posterior carina is absent or weakly developed.
Remarks: The present Pa elements may be the juveniles
of Palmatolepis juntianensis. The Pa element of Palmatolepis
juntianensis has an elongate platform with generally raised
margins and a weakly developed outer lobe. In the Pa element
of Palmatolepis minuta elegantula with a similar platform
outline, the anterior margin of the outer platform is about at a
right angle to the free-blade.
Family: Polygnathidae Bassler, 1925
Genus: Polygnathus Hinde, 1879
Type species: Polygnathus dubius Hinde, 1879
Polygnathus lodinensis Pölsler, 1969
1969 Polygnathus lodinensis Pölsler, p. 425426, Pl. 6, Figs. 112
1989 Polygnathus lodinensis Pölsler Klapper et Lane, Pl. 2, Fig. 1
Remarks: Polygnathus lodinensis is the most common
Polygnathus species in the studied stratigraphic section. Dis-
tinctive characteristics of the Pa element of this species are a
strongly arched platform, a short free-blade with about half-
length of the platform, and a sharply pointed posterior tip. The
Pa elements of Polygnathus timanicus are distinguished from
this species by very prominent convex bowing of the inner an-
terior platform margin, which makes the platform highly
asymmetrical, and a rounded posterior tip. The Pa element of
Polygnathus decorosus has a longer free blade, and a more
Genus: Polylophodonta Branson et Mehl, 1934a
Type species: Polygnathus gyratilineatus Holmes, 1928
Diagnosis: Pa element has a platform with well-devel-
oped rostral ridges in the anterior two-thirds, and irregular
transverse ridges in the posterior one-third. There are three
rostral ridges on the outer platform that are parallel each other,
and only one rostral ridge on the inner platform. They are sep-
arated by wide adcarinal troughs from the carina, and parallel
the carina anteriorly and diagonal it posteriorly. The carina
changing widely spaced nodes posteriorly does not arrive to
the posterior tip of the platform.
Remarks: The species is treated in open nomenclature
because only a single specimen was found.
Three of the standard upper Frasnian conodont zones (Low-
er rhenana to linguiformis) and six of the standard lower Fa-
mennian conodont zones (Middle triangularis to Latest crepi-
da Zone) of Ziegler & Sandberg (1990) have been recognized
from dark grey, generally nodular limestone beds of the Ay-
ineburnu Formation (Fig. 2). The Lower triangularis Zone
and F/F boundary have not been recognized in the studied
stratigraphic section. There is an unsampled interval of about
one meter between samples 63 (the linguiformis Zone) and 62
(the Middle triangularis Zone), which is generally covered by
recent sediments (Fig. 2). This interval can partly represent the
Lower triangularis Zone, and includes the F/F boundary.
However, the assign is questionable due to the absence of the
zonal name bearer taxa. Furthermore, most of the conodont
faunas from the lowest Famennian strata (samples 6260) are
densely covered by matrix, hindering the determination of
specimens, suggesting a reworking.
The F/F boundary interval in some other locations in the
world is characterized by a hiatus, caused by the absence of
the Lower triangularis Zone or the complete triangularis
Zone. Horizons of non-deposition and gaps were often found
in shallow water sediments (Metzger 1989; Piecha 2002; Over
2002). In the South Polish Moravian shelf basins, the Lower
triangularis Zone is at least conspicuously reduced in thick-
ness, even in the distal slope to basinal sequences, and a thin-
ning is also noted in the Middle triangularis Zone (Racki et al.
2002). In some sections of the basinal facies from Germany,
the Lower triangularis Zone is thinner from one meter (see
Sandberg et al. 1988; Ziegler & Sandberg 1990).
In the studied stratigraphic section, the appearance of Pal-
matolepis crepida, defining the base of the Lower crepida
Zone, is some above the base of this zone as in many sections
in the world (Schülke 1995, p. 28), and therefore the lower
boundary has been recognized by the first occurrences of Pal-
matolepis quadrantinodosalobata and Pelekysgnathus incli-
natus, as indicated by Schülke (1995, p. 28). The boundary
between the Lower and Middle crepida Zones could not also
be determined due to the lack of the defining taxa (Table 2).
Acknowledgments: I would like to thank my nephew Çetin
Civil who helped me during the collection of samples, Ismet
Gedik who reviewed the early manuscript, and Miðraç Akçay
who made some linguistic corrections. Thanks are extended to
Jindøich Hladil, D. Jeffrey Over, Jerzy Dzik and Matthias
Piecha who reviewed the manuscript and made valuable sug-
Bassler R.S. 1925: Classification and stratigraphic use of conodonts.
Geol. Soc. Amer. Bull. 36, 218220.
Becker G., Lazreq N. & Weddige K. 2003: Ostracods of Thuringian
provenance in the Lower Devonian of Eurasia and North Africa
UPPER DEVONIAN CONODONT BIOSTRATIGRAPHY OF THE ISTANBUL ZONE (NW TURKEY) 235
with special reference to the Emsian of Morocco. Cour. Fors-
chungsinst. Senckenberg 242, 3949.
Bischoff G. 1956: Oberdevonische Conodonten (to Iδ) aus dem Rheinis-
chen Schiefergebirge. Not.-Bl. Hess. Landesamt. Bodenforsch. 84,
Branson E.B. & Mehl M.G. 1934: Conodonts from the Grassy Creek
Shale of Missouri. Univ. Missouri Studies 8, 3, 171259, 1933.
Cooper C.L. 1931: New conodonts from the Woodford Formation of
Oklahoma. J. Paleontology 5, 230243.
Çapkônoûlu ª. 1997: Conodont fauna and biostratigraphy of the Famen-
nian of Büyükada, Istanbul, Northwestern Turkey. Boll. Soc. Pale-
ont. Ital. 35, 2, 165185.
Çapkônoûlu ª. 2000: Late Devonian (Famennian) conodonts from
Denizliköyü, Gebze, Kocaeli, Northwestern Turkey. Turkish J.
Earth Sci. 9, 23, 91112.
Gedik I. 1975: Die Conodonten der Trias auf der Kocaeli-Halbinsel
(Türkei). Palaeontographica Abt. A 150, 99160.
Göncüoûlu M.C. & Kozur H.W. 1998: Remarks on the pre-Variscan de-
velopment in Turkey. Schr. Staatl. Mus. Min. Geol. 9, 137138.
Haas W. 1968: The Devonian of Bithynia, northwest Turkey. In: Oswald
D.H. (Ed.): International Symposium on the Devonian System, Cal-
gary. Alberta Society of Petroleum Geologists, 2, 6166 (1967).
Han Y. 1987: Study on Upper Devonian Frasnian/Famennian boundary
in Ma-Anshan, Zhongping, Xiangzhou, Guangxi. Chinese Acad.
Geol. Sci. Bull. 17, 171194.
Helms J. 1959: Conodonten aus dem Saalfelder Oberdevon (Thüringen).
Geologie 8, 6, 634677.
Helms J. 1963: Zur Phylogenese und Taxionomie von Palmatolepis
(Conodontida, Oberdevon). Geologie 12, 4, 449485.
Hinde G.J. 1879: On conodonts from the Chazy and Cincinnati Group
of the Cambro-Silurian, and from the Hamilton and Genesee-Shale
divisions of the Devonian, in Canada and the United States. Geol.
Soc. London, Quart. J. 35, 351369.
Holmes G.B. 1928: A bibliography of the conodonts with descriptions
of Early Mississippian species. Proc. U. S. Nat. Mus. 72, 5, 138.
Kalvoda J., Leichmann J., Bábek O. & Melichar R. 2003: Brunovistu-
lian terrane (Central Europe) and Istanbul Zone (NW Turkey): Late
Proterozoic and Paleozoic tectonostratigraphic development and
Paleogeography. Geol. Carpathica 54, 3, 139152.
Kaya O. 1973: The Devonian and Lower Carboniferous stratigraphy of
the Istinye, Bostancô and Büyükada subareas. In: Kaya O. (Ed.):
Paleozoic of Istanbul. Ege Üniversitesi Fen Fakültesi Kitaplar
Serisi 40, 135.
Khalymbadzha V.G. & Chernysheva N.G. 1978: Conodonts of the Up-
per Devonian deposits of the central part of the Volga-Urals region
and their stratigraphic significance. In: Gusev A.K. (Ed.): Paleozo-
ic stratigraphy and paleontology of the Eastern Russian platform
(in Russian). Kazan University, 342.
Klapper G. 1989: The Montagne Noire Frasnian (Upper Devonian) con-
odont successions. In: McMillan N.J., Embry A.F. & Glass D.J.
(Eds.): Devonian of the World. Canad. Soc. Petrol. Geol., Mem.
14, 3, 449468 (imprint 1988).
Klapper G. & Becker R.T. 1999: Comparison of Frasnian (Upper De-
vonian) Conodont Zonations. Boll. Soc. Paleont. Ital. 37, 23,
Klapper G., Feist R., Becker R.T. & House H.R. 1994: Definition of the
Frasnian/Famennian stage boundary. Episodes 4, 433441 (imprint
Klapper G. & Foster Jr. C.T. 1993: Shape analysis of Frasnian species of
the Late Devonian conodont genus Palmatolepis. Paleont. Soc.
Mem. 32 (J. Paleont. 67, 4, Supplement) 135.
Klapper G. & Lane H.R. 1989: Frasnian (Upper Devonian) conodont se-
quence at Luscar Mountain and Mount Haultain, Alberta Rocky
Mountains. In: McMillan N.J., Embry A.F. & Glass D.J. (Eds.):
Devonian of the World. Canad. Soc. Petrol. Geol., Mem. 14, 3,
469478 (imprint 1988).
Klapper G., Kuzmin A. & Ovnatanova N.S. 1996: Upper Devonian con-
odonts from the Timan-Pechora Region, Russia, and correlation with
a Frasnian composite standard. J. Paleont. 70, 1, 131152.
Klapper G., Uyeno T.T., Armstrong D.K. & Telford P.G. 2004: Con-
odonts of the Williams Island and Long Rapids Formations (Upper
Devonian, Frasnian-Famennian) of the Onakawana B drillhole,
Moose River Basin, Northern Ontario, with a revision of lower Fa-
mennian species. J. Paleont. 78, 2, 371387.
Kozur H.W. & Göncüoûlu M.C. 1999: Differences in the geological
evolution of the Istanbul and Zonguldak terranes, northern Turkey.
Peshaver Meeting IGCP 421, Abstract Book, 1618.
Metzger R.A. 1989: Upper Devonian (Frasnian-Famennian) conodont
biostratigraphy in the subsurface of north-central Iowa and south-
eastern Nebraska. J. Paleont. 63, 4, 503524.
Metzger R.A. 1994: Multielement reconstructions of Palmatolepis and
Polygnathus (Upper Devonian, Famennian) from the Canning Ba-
sin, Australia, and Bactrian Mountain, Nevada. J. Paleont. 68, 3,
Miller A.K. & Yougquist W. 1947: Conodonts from the type section of
the Sweetland Creek Shale in Iowa. J. Paleont. 21, 501517.
Müller K.J. 1956: Zur Kenntnis der Conodonten-Fauna des Europäis-
chen Devons, 1. Die Gattung Palmatolepis. Abh. Senckenberg.
Naturforsch. Gessell. 494, 170.
Müller K.J. & Müller E.M. 1957: Early Upper Devonian (Indepen-
dence) conodonts from Iowa, Part 1. J. Paleont. 31, 10691108.
Okay A.I. 1987: Notes on the geology of Northwest Turkey. IGCP
Project No 5., Correlation of Variscan and Pre-variscan events of
the Alpine-Mediterranean Mountain Belt. Guide book for the field
excursion along western Anatolia, Turkey, 111.
Okay A.I., ªengör A.M.C. & Görür N. 1994: Kinematics history of the
opening of the Black Sea and its effect on the surrounding regions.
Geology 22, 267270.
Okay A.I., Satôr M., Maluski H., Siyako M., Monie P., Metzger R. &
Akyüz S. 1996: Paleo- and Neo-Tethyan events in northwestern
Turkey: Geologic and geochronologic constraints. In: Yin A. &
Harrison M. (Eds.): Tectonics of Asia. Cambridge University
Over D.J. 2002: The Frasnian/Famennian boundary in central and east-
ern United States. Palaeogeogr. Palaeoclimatol. Palaeoecol. 181,
Ovnatanova N.S. 1969: New upper Devonian conodonts of central ar-
eas of Russian Platform and Timan. Trudy Vsesojuz. Neft. Nauè. -
Issled. Geol.-Razv. Inst. 93, 139141 (in Russian).
Ovnatanova N.S. 1976: New Late Devonian conodonts of the Russian
Platform. J. Paleont. 2, 210219.
Önalan M. 1982: Geology and sedimentary characteristics of the Pendik
region and Princeces Islands. Istanbul Üniversitesi Fen Fakültesi,
Jeoloji Bölümü. (unpublished thesis), 1156 (in Turkish).
Önalan M. 1988: Sedimentary characteristics and depositional environ-
ments of Istanbul Devonian sediments. Istanbul Üniv. Müh. Fak.
Yerbilimleri Dergisi 6, 12, 92108 (in Turkish).
Piecha M. 2002: A considerable hiatus at the Frasnian/Famennian
boundary in the Rhenish shelf region of northwest Germany.
Palaeogeogr. Palaeoclimatol. Palaeoecol. 181, 195211.
Pölsler P. 1969: Conodonten aus dem Devon der Karnischen Alpen
(Findenigkofel, Österreich). Jb. Geol. B.A. 112, 399440.
Racki G., Racka M., Matyja H. & Devleeschouwer X. 2002: The Fras-
nian/Famennian boundary interval in the South PolishMoravian
shelf basins: integrated event-stratigraphical approach. Palaeo-
geogr. Palaeoclimatol. Palaeoecol. 181, 251297.
Sandberg C.A. & Dreesen R. 1984: Late Devonian icriodontid biofacies
models and alternate shallow-water conodont zonation. In: Clark
D.L. (Ed.): Conodont biofacies and provincialism. Geol. Soc.
Amer. Spec. Pap. 196, 143178.
Sandberg C.A. & Ziegler W. 1973: Refinement of standard Upper De-
vonian Conodont Zonation based on the sections in Nevada and
West Germany. Geologica et Palaeont. 7, 97122.
Sandberg C.A., Ziegler W., Dreesen R. & Butler J.L. 1988: Late Frasnian
mass extinction: conodont event stratigraphy, global changes, and
possible causes. Cour. Forschungsinst. Senckenberg 102, 263307.
Sannemann D. 1955a: Beitrag zur Untergliederung des Oberdevons
nach Conodonten. Neu. Jb. Geol. Paläont., Abh. 100, 3, 324331.
Sannemann D. 1955b: Oberdevonische Conodonten (to IIα). Sencken-
bergiana Lethaea 36, 12, 123156.
Savage N.M. & Yudina A.B. 2000: Late Devonian Syvyu River Sec-
tion, Timan-Pechora Basin, Northwestern Russia. Boll. Soc. Pale-
ont. Ital. 37, 23, 361373.
Schülke I. 1995: Evolutive Prozesse bei Palmatolepis in der frühen Fa-
menne-Stufe (Conodonta, Ober-Devon). Göttinger Arb. Geol.
Paläont. 67, 1108.
Schülke I. 1999: Conodont multielement reconstructions from the early
Famennian (Late Devonian) of the Montagne Noire (Southern
France). Geologica et Palaeont. SB3, 1123.
Seymen I. 1995: Geology of the Izmit Gulf region (NW Turkey). In:
Meriç E. (Ed.): Quaternary sequence in the Gulf of Izmit. 121.
Stauffer C.R. 1938: Conodonts of the Olentangy Shale. J. Paleont. 12,
Sweet W.C. 1988: The Conodonta: morphology, taxonomy, paleoecolo-
gy, and evolutionary history of a long-extinct animal phylum.
Clarendon Press, Oxford, 1212.
Thomas L.A. 1949: Devonian-Mississippian formations of southeast
Iowa. Geol. Soc. Amer. Bull. 60, 403438.
Ulrich E.O. & Bassler R.S. 1926: A classification of the tooth-like fos-
sils, conodonts, with descriptions of American Devonian and Mis-
sissippian species. Proc. U.S. Nat. Mus. 68, 12, 63.
Yanev S.N. 1993: Gondwana Paleozoic terranes in the Alpine Collage
System on the Balkans. J. Himalayan Geol. 4, 2, 257270.
Youngquist W.L. 1945: Upper Devonian conodonts from the Indepen-
dence Shale (?) of Iowa. J. Paleontology 19, 355367.
Ziegler W. 1958: Conodontenfeinstratigraphische Untersuchungen an
der Grenze Mitteldevon/Oberdevon und in der Adorfstufe. Not.-Bl.
Hess. Landesamt. Bodenforsch. 87, 777.
Ziegler W. 1962: Taxionomie und Phylogenie Oberdevonischer Con-
odonten und ihre stratigraphische Bedeutung. Abh. Hess. L.-Amt.
Bodenforsch. 38, 1166.
Ziegler W. & Huddle J.W. 1969: Die Palmatolepis glabra-Gruppe
(Conodonta) nach der Revision der Typen von Ulrich & Bassler
durch J.W. Huddle. Fortschr. Geol. Rheinl. Westf. 16, 377386.
Ziegler W. & Sandberg C.A. 1990: The Late Devonian standard conodont
zonation. Cour. Forschungsinst. Senckenberg 121, 1115.