© Author(s) 2022. CC Atribution 4.0 LicenseGEOLOGIJA 65/2, 217-224, Ljubljana 2022
https://doi.org/10.5474/geologija.2022.012
Lower Permian (Artinskian) chondrichthyan tooth remains 
(Petalodontidae) from Dovje (Karavanke Mts., NW Slovenia) 
Spodnjepermski (artinskijski) ostanki zob morskih psov (Petalodontidae) iz Dovjega 
(Karavanke, SZ Slovenija)
Matija KRIŽNAR
Prirodoslovni muzej Slovenije, Prešernova 20, 1000 Ljubljana, Slovenija; e-mail: mkriznar@pms-lj.si
Prejeto / Received 28. 9. 2022; Sprejeto / Accepted 17. 11. 2022; Objavljeno na spletu / Published online 21. 12. 2022
Key words: Petalodontiformes, Petalodus ohioensis, Upper Paleozoic, Artinskian, Karavanke Mountains, 
Slovenia
Ključne besede: Petalodontiformes, Petalodus ohioensis, zgornji paleozoik, artinskij, Karavanke, Slovenija
Abstract
Fossil remains of chondrichthyan tooth bases (roots) were found in Lower Permian beds exposed along the 
forest road between Dovje and Plavški Rovt. These layers are part of the clastic development of the Trogkofel 
Group beds. They are composed of an alternation of dark to light-grey shales, siltstone, and sandstone with 
rare beds of the conglomerate. Within the clastic succession, layers or lenses of dark-grey to black limestones 
(biosparitic, biomicritic and oolitic) and limestone breccias occur. The limestone consists remains of algae, 
fusulinids, brachiopods, and mostly crinoids (Palermocrinus and Entrochus). Detail study has shown that two 
remains of tooth bases belong to the genus Petalodus, one of them to the species Petalodus ohioensis. The bases 
are tongue-shaped and come to a rounded point in the distal (base end) edge. On the surface of the base, the 
typical oval-shaped foramina are visible. In addition, the osteodentine is visible on the cross-section of one 
specimen. Teeth of Petalodus are often the most common chondrichthyan fossil vertebrate remains reported 
from the Carboniferous and Permian rocks of the USA, Europe, and Russia. In Slovenia, Petalodus ohioensis 
has been recorded only from Upper Carboniferous beds. The new record of Lower Permian remains contributes 
to the knowledge of this cosmopolitan but still common genus of Late Paleozoic chondrichthyans. 
 
Izvleček
Iz spodnjepermskih plasti med Dovjim in Plavškim Rovtom so bili odkriti fosilni ostanki korenin zob 
hrustančnic. Najdbe izhajajo iz klastičnih plasti Trogkofelske grupe, kjer se menjavajo temni do svetlo sivi 
glinavci in peščenjaki ter redke leče konglomeratov. Med plastmi se pojavljajo tudi zaporedja temno sivih in 
črnih apnencev in apnenčevih breč, ki vsebujejo fosilne ostanke alg, fuzulin, ramenonožcev in večji delež ploščic 
morskih lilij (rodov Palermocrinus in Entrochus). Novo odkrita ostanka zob sta dobro ohranjeni korenini, 
značilni za rod Petalodus in smo ju vsaj v enem primeru taksonomsko pripisali vrsti Petalodus ohioensis. Oba 
ostanka korenin imata jeziku podobno obliko, ki se proti koncu zaokroži. Na površini so opazne manjše odprtine 
(foramni), medtem ko je na enem primerku opazna tudi kostna struktura (osteodentin). Zobje rodu Petalodus se 
pojavljajo v karbonskih in permskih plasteh skoraj povsod po svetu, predvsem v ZDA, Evropi in Rusiji. V Sloveniji 
so bili dobro ohranjeni zobje vrste Petalodus ohioensis najdeni le v zgornjekarbonskih plasteh, medtem ko so 
novi ostanki iz spodnjega perma prvič predstavljeni tukaj. Nove najdbe iz Slovenije dopolnjujejo paleontološko 
sliko tega kozmopolitskega rodu poznopaleozojskih hrustančnic. 
218 Matija KRIŽNAR
Introduction 
The Petalodontiformes are a small intriguing 
group of late Paleozoic chondrichthyans, rang-
ing from the Carboniferous (Mississippian) to 
the Permian. Up to now, there are about 17 gen-
era referred to Petalodontiformes, but most are 
known principally from isolated teeth (Ginter et 
al. 2010; Lund et al., 2014). Petalodus is the long-
est-known petalodont cosmopolitan genus. The 
late Paleozoic chondrichthyans (»shark«) record 
from Slovenia consists of complete or partial re-
mains of petalodont teeth (Petalodontidae gen et. 
sp. ident. and Petalodus ohioensis) and one tooth 
of Glikmanius cf. occidentalis (for the references 
and the list of localities see Table 1). 
Geological and Stratigraphical settings 
In the Southern Karavanke Mts. the outcrops 
of Upper Paleozoic (Upper Carboniferous and 
Lower Permian) fossiliferous shallow marine de-
posits are scattered between Solčava and Dovje 
(Fig. 1). The broadest and best exposed Lower 
Permian beds are present north of Tržič, in the 
vicinity of famous fossil sites Dovžanova soteska 
and Jelendol (Novak, 2007; Novak & Skaberne, 
2009). In the western part of Southern Karavanke 
Mts. Lower Permian beds are mainly exposed 
Table 1. Compiled list of Late Paleozoic chondrichthyan teeth from the South Karavanke (NW Slovenia). Note: All listed spe-
cimens were figured in cited publications. *Preliminary identification of the specimen. 
Tabela 1. Pregledni seznam poznopaleozojskih ostankov zob hrustančnic iz južnih Karavank (SZ Slovenija). Opomba: vsi 
primerki so ilustrirani v citirani literaturi. *Preliminarno določeni primerki. 
Age (Stage) 
Starost (obdobje)
Species (number of the specimen) /  
Vrsta (število primerkov)
Fossil site - locality / 
Najdišče fosila 
Reference (Publication) / 
Referenca 
L
ow
er
 P
er
m
ia
n
(A
ss
el
ia
n
-A
rt
in
sk
ia
n)
Glikmanius cf. occidentalis (1) Hrušica (north), forest road near Na Visokih 
Križnar, 2015 
Križnar, 2016
Petalodontidae gen et. sp. indet. (1)* Dovžanova soteska 
Novak, 2006
Novak, 2019 
U
p
p
er
 C
ar
b
on
if
er
ou
s
(G
zh
el
ia
n)
Petalodus ohioensis (2) Javorniški Rovt, Spodnja Počivala 
Ramovš & Bedič, 1993
Ramovš, 1997 
Ramovš, 1998
Peternel,1995 
Petalodus ohioensis (1) Forest road Planina pod Golico - Črni vrh 
Ramovš, 1997 
Ramovš, 1998 
Petalodontidae gen et. sp. indet. (1) Planina pod Golico, brook southeast of the village Ramovš, 1998 
Petalodontidae gen et. sp. indet. (1) Črni vrh Peternel, 1995 
in Javorniški Rovt and Pristava, and between 
Planina pod Golico and Dovje village (Novak & 
Skaberne, 2009). 
The lithostratigraphic subdivision of Lower 
Permian rocks in the Southern Karavanke moun-
tains is composed of the Grenzland Fm., Zweik-
ofel Fm. and on top the Trogkofel Group (Novak 
& Skaberne, 2009, 199). In the youngest beds of 
the Trogkofel Group, carbonate and clastic devel-
opments are distinguished. The carbonate part is 
represented by light-grey, dark-red, and rose-red 
reef fossiliferous limestones and fore-reef lime-
stone breccias in some parts. The Trogkofel lime-
stone is massive (as reef bioherm) or thick-bedded 
and rich in fossils. The clastic development of the 
Trogkofel Group beds is composed of the alter-
nation of dark to light-grey shales, siltstone, and 
sandstone with rare beds of conglomerate (Novak 
& Skaberne, 2009). Within the clastic succession, 
layers or lenses of dark-grey to black limestones 
(biosparitic, biomicritic and oolitic) and lime-
stone breccias occur, containing rock-forming 
remains of algae, fusulinids, brachiopods, rare 
corals, and crinoids (Novak & Skaberne, 2009). 
The age of the Trogkofel Group (with Trogkofel 
limestone) in the Southern Karavanke is middle 
to late Artinskian, with a thickness of a maxi-
mum of 400 meters (Novak & Skaberne, 2009). 
219Lower Permian (Artinskian) chondrichthyan tooth remains (Petalodontidae) from Dovje (Karavanke Mts., NW Slovenia)
The outcrop of the newly discovered chon-
drichthyan tooth fragments is located along the 
forest road between Dovje and Plavški Rovt 
(Fig. 2). Layers of dark-grey limestones and an 
alternation of light-grey shales and siltstone are 
exposed. All beds are extremely fossiliferous 
with numerous disarticulated crinoid remains. 
The remains of crinoids are mostly fully disartic-
ulated parts (ossicles) of stems (columnals), arms, 
pinnules, and rarely crinoid crowns (Lach et al. 
2013). Crinoid remains were not yet the subject 
of a thorough paleontological investigation, but 
Fig. 1. Index map (top) showing the outcrops of Lower Permian clastic-carbonate beds in the Karavanke (Slovenian part) 
with the fossil location near Dovje. Summary of the Permian stratigraphy and biostratigraphy (bottom) of the Karavanke 
Mountains, with the position of fossil chondrichthyan teeth in the Trogkofel Group (adapted from Novak & Skaberne, 2009). 
Sl. 1. Zemljevid razprostranjenosti klastično-karbonatnih spodnjepermskih plasti v Karavankah (slovenski del) in pozicija 
najdišča fosilov pri Dovjem (zgoraj). Poenostavljen stratigrafski stolpec spodnjepermskih plasti v Karavankah (prirejeno po 
Novak & Skaberne, 2009).
220 Matija KRIŽNAR
preliminary research shows the presence of the 
crinoid genera Palermocrinus and Entrochus, 
with probably some members of Codiacrinidae 
(Lach et al., 2013; Ramovš & Sieverts-Doreck 
1968). The associated fauna is composed of bra-
chiopods (productids and spiriferids), bivalves, 
gastropods, foraminifers (fusulinids), algae 
(Shamovella-Archaeolithoporella), and fenestel-
lid bryozoans which are with the crinoids, form 
the main biotic component in some parts. Similar 
crinoidal limestone with Palermocrinus togatus, 
with higher carbonate content, is known at Prista-
va in Javorniški Rovt. The age of the outcrop with 
new fossil tooth remains is Artinskian (Novak & 
Skaberne, 2009; Novak M., personal comm.). 
Materials and methods 
Specimens were discovered by Jure Zupanc 
around the year 2000 and are stored in his pri-
vate geological collection. For the specimens 
described here, we use working identification 
numbers JZC 001 (Fig. 4) and JZC 002 (Fig. 5). 
Both specimens were prepared only with minor 
mechanical tools (needles) and measured with a 
metal hand vernier caliper. The specimens were 
photographed using a Nikon D7200 camera cou-
pled with an AF-S Micro NIKKOR 60mm f/2.8G 
ED lens. Photos of specimens were additionally 
edited with the advanced photo editing program 
Adobe Photoshop Lightroom which enhanced the 
visibility of some features. 
Our description of the tooth base (Fig. 3) fol-
lows combined terminology suggested by Dalla 
Vecchia, (1988), Robb (2003), Harper (2018, 7), and 
Gai et al. (2021, see their Fig. 2, a1-a3). 
Systematic Paleontology 
Systematics follows the taxonomic views of 
Ginter et al. (2010) and Carpenter & Itano (2019). 
Class Chondrichthyes Huxley 1880 
Subclass Euchondrocephali Lund & Grogan  
1997 
Order Petalodontiformes Patterson 1965 
Family Petalodontidae Newberry & Worthen 
1866
Genus Petalodus Owen 1840 
Petalodus ohioensis Safford 1853 
Figure 4
Fig. 2. A: The location of petalodontid teeth remains on a forest road in the vicinity of Dovje (13°58’14”, 46°28’1”). B-D: Various 
remains from crinoid-bryozoan-algae assemblage (biofacies) from the Dovje locality. Not to scale. Abbreviations: Cr - crinoid 
remains (mostly crinoid columnals); Brio - bryozoans; Alg -algae. 
Sl. 2. A: Najdišče petalodontidnih ostankov zob ob gozdni cesti v okolici Dovjega (13°58’14”, 46°28’1”). B-D: Različni fosilni os-
tanki iz krinoidno-briozojsko-algnih združb iz najdišča pri Dovjem. Ni v merilu. Okrajšave: Cr - krinoidni ostanki (prevladu-
jejo ploščice morskih lilij); Brio - briozoji (mahovnjaki); Alg – alge. 
221Lower Permian (Artinskian) chondrichthyan tooth remains (Petalodontidae) from Dovje (Karavanke Mts., NW Slovenia)
Material: One specimen of base of petalodon-
tid tooth (Fig. 4). Specimen (JZC 001) was discov-
ered by Jure Zupanc and is stored in his private 
geological collection. The specimen represents 
the complete tooth base (Fig. 4A-C) of a typical 
petalodont tooth. The tooth crown is missing. 
Description: The base is triangular in tongue 
shape and comes to a rounded point in the dis-
tal edge (base end). Transversely the base is oval. 
The mesiodistal width is 30 mm, and the total 
length is 36 mm. The maximal lingual-labial 
thickness of the tooth base is 6.4 mm. The lingual 
side of the base is bent to the labial side. On the 
surface of the lingual side, a few oval-shaped fo-
ramina are visible, on faint traces of ridges. On 
top of the base, the distal crown tongue is poorly 
preserved and overhangs the base. The labial side 
of the base has four elongated ridges, with no vis-
ible foramina, partially covered with a matrix. 
Fig. 3. Anatomical terminology of petalodontid tooth (Petalodus). Adapted from Dalla Vecchia, (1988), Robb (2003), and Gai 
et al. (2021). 
Sl. 3. Anatomska terminologija petalodontidnega zoba (Petalodus). Prirejeno po Dalla Vecchia, (1988), Robb (2003) in Gai et 
al. (2021).
Fig. 4. Petalodus ohioensis from Dovje locality. Specimen JZC 001: A - lingual, B - profile, C - labial views. The scale bar 
equals 10 mm. D - reconstructed position of the base in a tooth. 
Sl. 4. Petalodus ohioensis iz najdišča pri Dovjem. Primerek JZC 001: A - lingvalni, B - stranski, C - labialni pogledi, merilo je 
10 mm. D - rekonstrukcija položaja korenine na zobu. 
222 Matija KRIŽNAR
Petalodus cf. ohioensis Safford 1853 
Figure 5
Material: One specimen of base of petalodon-
tid tooth (Specimen JZC 002) (Fig. 5). The re-
mains represent a fragmentary but typical pet-
alodont tooth base (Fig. 5A-E). The tooth crown 
is missing. 
Description: The base is triangular in shape 
and it is transversely oval. The mesiodistal width 
of the preserved base is 33 mm. The maximal lin-
gual-labial thickness of the preserved tooth base 
is 9.5 mm. Labially the base is more concave and 
lingually convex. On both sides (lingual and la-
bial) three elongated (vertical) ridges are present. 
On the lingual side, the oval-shaped foramina are 
visible on all ridges. On the bordered part (top of 
the base), a small part of the distal crown tongue 
is present, with two rows of ridges. On both dis-
tal surfaces of the specimen, the spongy tissue 
is visible. According to Zangerl et al. (1993), this 
tissue is circumpulpar trabeculine (cavities) and 
trabecular dentine, or osteodentine by Dalla Vec-
chia, 1988 and Gai et al., 2021 (Fig. 5D-E). 
Discussion and Conclusion 
Teeth of Petalodus are often the most common 
chondrichthyan fossil remains reported from the 
Carboniferous and Permian rocks of the USA, 
Europe, Russia, and China (Ginter et al. 2010, 
141; Dalla Vecchia, 2008; Gai et al. 2021). The re-
mains are mainly isolated teeth. Petalodus ohio-
ensis is well known from Upper Carboniferous 
and Lower Permian beds and it is widespread 
(Hansen, 1985; Elliott et al, 2004, 277-278; Ginter 
et al. 2010, 141). The specimen presented here 
(JZC 001) (Fig. 4), preserved as a tooth base, is 
typical of Petalodus ohioensis. The shape of the 
tooth base is very similar in shape and dimen-
sions to specimens presented by Brusatte (2007, 
3, fig. 2), Harper (2018, 4, fig. 1), Ramovš & Bedič 
(1993, 149, fig. 1) and Ramovš (1997, 110, fig. 1). All 
these specimens come from Upper Carboniferous 
strata and are probably from the anterior part 
of Petalodus ohioensis jaw, based on shape and 
size of teeth base (Elliott et al, 2004, 277, fig. 5A-
B). Even though our second specimen (JZC 002) 
(Fig. 5) is broken, we attribute it to the genus Pet-
alodus. Its shape and dimensions and comparison 
with other specimens (see Brusatte, 2007; Harper, 
2018; Ramovš & Bedič 1993) allow us to classify it 
as Petalodus cf. ohioensis.
Fig. 5. Petalodus cf. ohioensis from Dovje locality. Specimen JZC 002: A - lingual, B - profile, C - labial views, D, E - distal sur-
faces with visible spongy tissue (osteodentine). The scale bar equals 10 mm. F – reconstructed position of the base in a tooth. 
Sl. 5. Petalodus cf. ohioensis iz najdišča pri Dovjem. Primerek JZC 002: A - lingvalni, B - stranski, C - labialni pogled, D, 
E - distalna površina primerka z vidno kostno strukturo (osteodentin), merilo je 10 mm. F - rekonstrukcija položaja korenine 
na zobu. 
223Lower Permian (Artinskian) chondrichthyan tooth remains (Petalodontidae) from Dovje (Karavanke Mts., NW Slovenia)
The new finding increases the petalodont di-
versity in the Southern Alps, and also sheds new 
light on the distribution and stratigraphic range 
of petalodonts in Slovenia and this part of Eu-
rope. 
Acknowledgments 
I would like to thank Jure Zupanc for donating 
valuable specimens studied in this paper. I would 
also like to thank dr. Matevž Novak for his helpful 
comments on the stratigraphy of Permian beds from 
fossil locality. I am grateful to the anonymous revi-
ewers for their valuable comments and suggestions 
that helped improve the manuscript. 
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