© Author(s) 2023. CC Atribution 4.0 License Microfossils from Middle Triassic beds near Mišji Dol, central Slovenia Mikrofosili iz srednjetriasnih plasti pri Mišjem Dolu, osrednja Slovenija Katja OSELJ 1,2 , Tea KOLAR-JURKOVŠEK 3 , Bogdan JURKOVŠEK 3,4 & Luka GALE 2,3 1 Trboje 104, 4000 Kranj, Slovenia; e-mail: katja.oselj@gmail.com; 2 Department of Geology, Faculty of Natural Sciences and Engineering, University of Ljubljana, Aškerčeva cesta 12, 1000 Ljubljana, Slovenia; e-mail: luka.gale@ntf.uni-lj.si 3 Geological Survey of Slovenia, Dimičeva ulica 14, SI-1000 Ljubljana, Slovenia; e-mail: tea.kolar-jurkovsek@geo-zs.si; luka.gale@geo-zs.si; 4 Kamnica 27, 1262 Dol pri Ljubljani, Slovenia; e-mail: geolog.bj@gmail.com Prejeto / Received 13. 3. 2023; Sprejeto / Accepted 29. 5. 2023; Objavljeno na spletu / Published online 4. 8. 2023 Key words: Dinarides, Sava Folds, Middle Triassic, upper Anisian, lower Ladinian, basin, volcaniclastics, conodonts, foraminifera Ključne besede: Dinaridi, Posavske gube, srednji trias, zgornji anizij, spodnji ladinij, bazen, vulkanoklastiti, konodonti, foraminifere Abstract Middle Triassic beds exposed along the road between Mišji Dol and Poljane pri Primskovem (Posavje Hills) comprise marlstone, tuff, volcaniclastic sandstone, and thin- to medium-bedded limestone and dolostone. The succession was logged and sampled for conodonts. A relatively rich conodont assemblage was determined, consisting of Budurovignathus gabrielae Kozur, Budurovignathus sp., Cratognathodus kochi (Huckriede), Gladigondolella malayensis Nogami, Gladigondolella tethydis Huckriede, Gladigondolella sp., Neogondolella balkanica Budurov & Stefanov, Neogondolella cf. excentrica Budurov & Stefanov, Neogondolella constricta (Mosher & Clark), Neogondolella cornuta Budurov & Stefanov, Neogondolella sp., Paragondolella excelsa Mosher, Paragondolella liebermani (Kovacs & Kozur), Paragondolella trammeri (Kozur), Paragondolella cf. alpina (Kozur & Mostler), and Paragondolella sp. The assemblage correlates with the upper Anisian and lowermost Ladinian assemblages from the Global Boundary Stratotype Section and Point (GSSP) of the Ladinian at Bagolino in the Southern Alps in northern Italy. Along with conodonts, numerous specimens of benthic foraminifera Nodobacularia? vujisici Urošević & Gaździcki were recovered from the lowermost part of the succession. Previous research on this taxon is critically evaluated. Izvleček Zaporedje srednjetriasnih plasti, ki so razgaljene ob cestnem useku med Mišjim Dolom in Primskovim (Posavsko hribovje), sestavljajo laporovec, tuf, vulkanoklastični peščenjak in tanko do srednje plastnat apnenec in dolomit. Zaporedje je bilo popisano in vzorčeno za konodontne analize. Določena je bila relativno bogata združba, ki sestoji iz vrst Budurovignathus gabrielae Kozur, Budurovignathus sp., Cratognathodus kochi (Huckriede), Gladigondolella ma- layensis Nogami, Gladigondolella tethydis Huckriede, Gladigondolella sp., Neogondolella balkanica Budurov & Stefanov, Neogondolella cf. excentrica Budurov & Stefanov, Neogondolella constricta (Mosher & Clark), Neogondolella cornuta Budurov & Stefanov, Neogondolella sp., Paragondolella excelsa Mosher, Paragondolella liebermani (Kovacs & Kozur), Paragondolella trammeri (Kozur), Paragondolella cf. alpina (Kozur & Mostler) in Paragondolella sp. Združbo lahko ko - reliramo z zgornjeanizijsko do spodnjeladinijsko združbo iz globalnega mejnega stratotipskega profila in točke (GSSP) za ladinij v Bagolinu v Južnih Alpah, severna Italija. Poleg konodontov so bili v spodnjem delu zaporedja najdeni številni primerki bentoških foraminifer Nodobacularia? vujisici Urošević & Gaździcki. Podajamo kritični pregled dosedanjih raz - iskav tega taksona. GEOLOGIJA 66/1, 107-124, Ljubljana 2023 https://doi.org/10.5474/geologija.2023.004 ta-Maliac) Ocean (Schmid et al., 2008; Kovács et al., 2011). As a result, several smaller basins were created, mainly between late Anisian and early Ladinian (Buser, 1989; Haas & Budai, 1999; Bu- dai & Vörös, 2006; Berra & Carminati, 2010; Ste- fani et al., 2010; Velledits et al., 2011; Gawlick et al., 2012; Celarc et al., 2013; Smirči ć et al., 2020). Introduction The Middle Triassic tectonic and paleogeo- graphic evolution of the present-day Southern Alps, Dinarides, Northern Calcareous Alps, and Transdanubian Range was strongly affected by crustal extension that accompanied the opening and spreading of the western Neotethys (Melia- 108 Katja OSELJ, Tea KOLAR-JURKOVŠEK, Bogdan JURKOVŠEK & Luka GALE Tectonic activity was accompanied by volcanism, which is reflected in the local deposition of volca- niclastic and/or volcanic rocks, mostly within the basinal areas (Buser, 1989; Gianolla et al., 2019). Upper Anisian to Ladinian basinal successions are relatively widespread in the territory of Slovenia (see Dozet & Buser, 2009 and Kolar-Jurkovšek & Jurkovšek, 2019 for summary). Local differences among the successions evidence the existence of several basins of different depths and characters, ranging from open marine environments (Rakovec, 1950; Buser, 1986; Skaberne et al., 2003; Rožič et al., 2021), to ephemeral marshes, river systems, freshwater lakes, and shallow restricted lagoons (Čar, 2013). The ruggedness of the relief is well ex- emplified in the Idrija area, where at least three Ladinian sedimentary basins separated by topo- graphic ridges were recognised (Čar, 2013). Deter- mination of age is crucial for exact stratigraphic position and correlation of this plethora of differ- ent depositional environments. Limestones from open marine and well-aerated basins often contain conodonts (Celarc et al., 2013; Kolar-Jurkovšek & Jurkovšek, 2019), radiolarians (Goričan & Buser, 1990; Ramovš & Goričan, 1995; Skaberne et al., 2003; Celarc et al., 2013), and bivalves (Jurkovšek, 1984), while ammonoids are rarely found (Čar, 2010). Foraminifera are also present, but they are usually not abundant (Jurkovšek, 1984). Numer- ous Middle Triassic deposits, however, remain poorly dated (e.g., the shale- and sandstone-domi- nated Pseudozilian beds in the central and western Slovenia; Rakovec, 1950; Buser, 1986; Čar et al., 2021). A Middle Triassic volcanoclastic unit between Mišji Dol and Poljane pri Primskovem in the cen- tral Posavje Hills was previously mentioned by Li- pold (1858), Germovšek (1955), and Buser (1974). Some ammonoid and bivalve taxa were determined (Lipold, 1858; Germovšek, 1955; Buser, 1974; also Jurkovšek, 1984 for localities in vicinity). A de- tailed description of a volcano-sedimentary suc- cession from Obla Gorica in the vicinity was given by Dozet (2006), who divided the succession into (from bottom/older to top/younger): bedded tuff with interbeds of limestone (1), lower platy dolo- stone with chert and tuff interbeds (2), light grey bedded dolostone with tuff interbeds (3), upper platy dolostone with cherts and tuff interbeds (4), dark marly limestone and marlstone (5); tuff with interbeds of volcaniclastic sandstone (6), and bed- ded and platy grained limestone (7). A renewed sampling of Middle Triassic beds between Mišji Dol and Poljane pri Primskovem yielded a rela- tively rich and well-preserved conodont and fora- miniferal fauna. The aim of this paper is to present the recovered conodont and foraminiferal assem- blages for a better stratigraphic assignment of the Upper Anisian to Ladinian beds in the researched area. The conodont assemblage is compared to other assemblages from the region. Geological setting According to Placer (1998a, 2008), the stud- ied area structurally belongs to the External Di- narides and the Sava Folds (Placer, 1998b). The studied succession is a part of the Litija Anticline (Placer, 1998b), created by post-Miocene com- pression (Placer, 1998b; Tomljenović & Csontos, 2001). The pre-folding structure of the External Dinarides was largely governed by Oligocene– early Miocene thrusting in the NE-SW direction Fig. 1. Geographic position of the studied section. a: Position of area depicted in Fig. 1b. b: Position of the section along the road from Mišji Dol to Poljane pri Primskovem. LIDAR digital model of the relief, 2015. Data source: Slovenian Environment Agency. Accessed via Geopedia portal (Sinergise d.o.o.) in November 2022. 109 Microfossils from Middle Triassic beds near Mišji Dol, central Slovenia (Placer, 1998a, 1998b; Vrabec & Fodor, 2006). The logged succession of Middle Triassic beds lies along the road between Mišji Dol and Poljane pri Primskovem (Fig. 1), starting at 45°59´28.43´´N, 14°54´37.56´´E and ending at 45°59´0.71´´N, 14°54´5 4 .15´´E . The succession is folded, dissect- ed by numerous minor faults, and partly covered. According to Buser (1968) and Dozet (2006), the investigated succession unconformably overlies massive Anisian dolostone and is succeeded up- wards by the massive Ladinian dolostone. Material and methods Due to the partial coverage of the succession, we were only able to reconstruct the succession by combining the outcropping segments. Thirty-one conodont samples were collected along the suc- cession, weighting between 1.5 and 2.5 kg. The rock was dissolved in 10–15 % acetic acid and the residue was separated into light and heavy frac- tions with the use of bromoform. Conodonts from the heavy fraction and foraminifera from the light fraction were hand-picked under a binocular mi- croscope. In some instances, the interior of fora - minifera could be viewed by immersing them in glyceryl. We also prepared some oriented thin sec- tions of foraminifera. Selected specimens of cono- donts and foraminifera were photographed with a scanning electron microscope (SEM) JEOL JSM 6490LV. The macroscopic lithological description was supplemented by micropetrographic analysis of 49 thin sections using a polarizing optical mi- croscope. Carbonate rocks were classified accord- ing to Dunham (1962), Embry and Klovan (1972), and Wright (1992). The terminology of volcani- clastics follows Di Capua et al. (2022). Similarities with other conodont assemblages from the same time interval were evaluated using the Dice simi- larity index using PAST v. 2.17c statistics software (Hammer et al., 2001). Preparatory work and SEM microscopy were performed at the Geological Sur- vey of Slovenia. The conodont samples are stored at the Geological Survey of Slovenia under repos- itory numbers 6247–6264. The thin sections are stored in repository of the co-author L.G. at the Department of Geology, Faculty of Natural Scienc- es and Engineering in Ljubljana. Results Description of section The succession was investigated along 1100 m long road section. The contact with the massive Anisian dolostone is not exposed. The general ori- entation of bedding changes from 235/42 in the lower part of the succession, to 190/40 halfway along the roadcut, and to 200/50 near the top. Despite this relative consistency in the general orientation of the bedding, small-scale folds and faults are present, which makes the estimate of the thickness of individual sub-sections very difficult. We estimate that the entire succession is between 100 and 200 m thick. Figure 2 shows some bet- ter exposed parts of the succession, and Figure 3 the reconstructed generalized succession and po- sition of conodont samples within it. The general succession starts with a variegated succession of marlstone, tuff, and thin-bedded limestone. High- er up in the succession thin- to medium-bedded limestone and dolostone predominate, commonly interchanging with volcaniclastic sandstone. The top of the roadcut is again dominated by poorly exposed variegated succession of tuff, volcani- clastic sandstone, marlstone, and limestone. The lithological composition of each sector along the road and the actual thickness of each part of the succession is presented in Table 1. Fig. 2. Middle Triassic beds between Mišji Dol and Poljane pri Primskovem. a: Dolomitized cherty limestone with thin interbeds of volcan- iclastic sandstone; sector 13. b: Thin bedded limestone (radiolarian-filament wackestone/packstone); sector 21. 110 Katja OSELJ, Tea KOLAR-JURKOVŠEK, Bogdan JURKOVŠEK & Luka GALE Fig. 3. Reconstruction of the Middle Triassic succession along the road between Mišji Dol and Poljane pri Primskovem. The true stratigraphic thickness of each sector is shown (see thicknesses in Table 1). The right-hand side presents the position of the conodont samples and the stratigraphic distribution of the conodont species. The Anisian/Ladinian boundary is within the trammeri zone. 111 Microfossils from Middle Triassic beds near Mišji Dol, central Slovenia Sector Lithology Total thickness Microfacies 1 Covered by soil. Marlstone and pelitic tuff (80 %) in 1–5 cm thick beds, locally with chert and thin-shelled bivalves, concordant to bedding. -Dark limestone in up to 7 cm thick beds (18 %); locally with bands with thin-shelled bivalves, concordant to bedding. Locally silicified. -V olcaniclastic sandstone (2 %) forms up to 3.5 cm thick beds. Weath- ered pieces are light yellow in colour. 16 m (estimated) Limestone: -radiolarian-filament-peloid packstone; -bioclastic-intraclastic grainstone; -peloid-bioclastic packstone/grainstone 2 The lower part (1.2 m) is dominated by limestone, the next 4.2 m by tuff and volcaniclastic sandstone. Micritic limestone and breccia (45 cm thick) follow, then a 1.5 m thick bed of marlstone, and two more beds (20 cm and 25 cm thick) of breccia. -Limestone is dark grey to black, locally selectively silicified. Bed thickness is from 1 cm to 15 cm. Bivalve shells and radiolarians were recognised with a hand-lens. -Tuff and volcaniclastic sandstone is present in 1–15 cm thick beds. The colour is yellow, green, brownish green or greenish grey. -Marlstone is dark brown in colour and laminated. -Breccia is poorly sorted; the largest clasts from the top of the bed are 4 cm across. 8.2 m (logged in detail) Limestone: -calcimudstone; -radiolarian-filament wackestone/packstone; -bioclastic-intraclastic rudstone Clastics: -calcareous mudstone; -volcaniclastic sandstone; -mud-supported sandy breccia 3 Mostly covered. Marlstone dominates (90 %) over a few beds of volca- niclastic sandstone and black pelitic tuff. 9 m (estimated) Clastics: -calcareous mudstone; -volcaniclastic sandstone 4 Mostly covered. Marlstone. 6 m (2 m exposed, the rest estimated) / 5 Covered. ? (estimated 3 m) / 6 Black marly limestone, locally with chert. 1 m / 7 Covered. ? (estimated 3 m) / 8 Three beds of black micritic limestone. 1.5 m / 9 Mostly covered. Fragments of black micritic limestone are found over 75 % of this interval; the rest is probably grey dolostone and volcani- clastic sandstone. 18 m (estimated) / 10 Light grey dolostone, fractured and folded. Bedding is not clear. ? (estimated 5 m at most) Dolostone: -dolomitized intraclastic grainstone/rud- stone?; subhedral 11 Grey dolostone in 1.5–8 cm thick beds. ? (estimated 3 m) Dolostone: -dolomitized intraclastic grainstone/rud- stone?; subhedral 12 Covered. Fragments of volcaniclastic sandstone and dolostone. ? (estimated 2 m) / 13 Bedded dolomitized cherty limestone with cleavage. Beds are 0.5– 34.5 cm thick. They interchange with beds of volcaniclastic sandstone. 6 m Dolostone: -subhedral; locally with chert 14 Covered. Fragments of dolostone and volcaniclastic sandstone. ? (estimated 3 m) Clastics: -volcaniclastic sandstone; grains of volcanics, quartz, feldspar, microsparitic lithoclasts 15 V olcaniclastic sandstone. ? (estimated 1 m) Clastics: -sandstone with grains of poli- and monocrys- tal quartz, chloritized volcanics, feldspar; sericitic matrix and dolomitic cement 16 Covered. Fragments of dolostone and limestone. ? (estimated 2 m) Dolostone: - subhedral; 10% of terrigenous quartz, rare echinoderms are preserved 17 Dolomitized limestone in app. 5 cm thick beds. 1 m / 18 Covered. Fragments of dolostone and volcaniclastic sandstone. ? (estimated 1–3 m) / 19 Dolostone in 2–34 cm thick beds. Laterally pinching out and lateral amalgamation of beds suggest slumping. 2 m Dolostone: - subhedral; dolomitized grainstone or rud- stone (remains of echinoderms and intra- clasts) and packstone with filaments 20 Folded thin-bedded (0.5–2 cm) dolostone, subordinately limestone. 2 m Dolostone: -subhedral; chert nodules Limestone: -radiolarian-filament wackestone/packstone 21 Dark grey to black limestone in 3.5–12 cm thick beds. Parallel lamina- tion and silicification are locally present. Subordinate are thin marlstone interlayers. 7 m Limestone: -radiolarian-filament wackestone/packstone Table 1. Lithological composition of Middle Triassic beds between Mišji Dol and Poljane pri Primskovem. 112 Katja OSELJ, Tea KOLAR-JURKOVŠEK, Bogdan JURKOVŠEK & Luka GALE Sector Lithology Total thickness Microfacies 22 Dolostone in 5.5–19 cm thick beds. One bed shows cross-lamination. Subordinate are thin marly interlayers. Cleavage is present. 7 m Dolostone: -dolomitized filament packstone/grainstone and intraclastic rudstone; subhedral 23 Covered. Fragments of limestone and volcaniclastic sandstone. ? (estimated 1.5 m) Limestone: -peloid-bioclastic packstone/grainstone 24 Partly covered. Dolomitized limestone in 2–7.5 cm thick, folded beds. Large part of the succession covered by a concrete wall. 3 m + unknown + 3 m Dolostone: -subhedral; remains of brachiopods/bivalves and echinoderms; selective silicification 25 Thin beds of dolostone (1.5–13 cm), interchanging with volcaniclastic sandstone. 6 m Dolostone: -subhedral; remains of echinoderms, fila- ments; 5 % of terrigenous quartz 26 Dolostone in 4–22 cm thick beds. Nodules of chert and laminae are locally present. 7 m Dolostone: -subhedral; selective silicification 27 Dark grey to black limestone in 4–20 cm thick beds. Cross-lamination is locally present. 1.5 m (estimated) Limestone: -peloid-bioclastic packstone/grainstone 28 Mostly covered. Fragments of volcaniclastic sandstone and limestone. Exposed beds of limestone are 2–29 cm thick. Parallel lamination is locally visible. ? (estimated 5 m) Limestone: -peloid-bioclastic packstone/grainstone; -bioclastic-intraclastic-peloid grainstone with terrigenous admixture 29 V olcaniclastic sandstone in 0.5–10 cm thick beds. 1 m Clastics: -volcaniclastic sandstone 30 Covered. Variegated succession of tuff, volcaniclastic sandstone, lime- stone, dolostone. ? (estimated 50 m) Clastics: -volcaniclastic sandstone Microfacies Description Calcimudstone Texture is homogenous. Micritic matrix strongly predominates. Only 5 % of the area is occupied by grains (radiolarians). Radiolarian-filament wackestone/packstone Texture is heterogenous, locally bioturbated. Matrix represents 50–70 % of the area, grains 30–50 %. Grains are well sort- ed, supported by matrix or in point contacts. The average grain size is 0.4 mm. Among grains, bioclasts predominate (90 % of grains). These are mostly filaments and radiolarians, while ostracods and benthic foraminifera (Frondicularia wood- wardia Howchin, Lagenida) are rare. Peloid-filament-radio- larian packstone This microfacies interchanges with bioclastic-intraclastic grainstone in wide laminae. Texture is homogenous. Grains represent 85 % of the area, whereas matrix and spar represent 15 % of the area of thin section. Sorting is moderate. Grains are in point and long contacts, and they measure 0.03–1 mm in size. Spherical forms are the most common. Peloids and pellets represent 80 % of grains. Filaments (10 %) and radiolarians (7 %) are subordinate. Less abundant are echinoderms and foraminifera (Krikoumbilica sp.). Echinoderm plates are overgrown by syntaxial calcite cement. The calcite cement in intergranular space is fine-grained, locally drusy mosaic. Bioclastic-peloid pack- stone/grainstone Texture is homogenous. Grains form 80 % of the area, matrix and cement 20 %. Sorting is moderate. Grains are 0.11– 4.9 mm large. They are in point and long contacts. Geopetal structures are present within gastropod shells. Biogenic grains represent 40–50 % of the grains. Peloids (35–40 %), aggregate grains (5–10 %), and intraclasts (5–15 %) are also common- ly present. Less abundant are bivalves, echinoderms, foraminifera (sessile agglutinated foraminifera, Glomospirella sp., Pa- laeolituonella meridionalis (Luperto), Endoteba sp., Endotriadella sp., Variostoma sp., Duostominidae), microproblematica (Plexoramea cerebriformis Mello, Tubiphytes obscurus Maslov), gastropods (locally more common), brachiopods, Terebel- la tubes, and dasycladacean algae. Radiolarians are present where the micritic matrix is present. Terrigenous component is subordinate to allochems. Monocrystal quartz with uniform extinction is present in angular grains measuring 0.5–0.6 mm in size. Lithic grains of chert are locally also present. The cement is fine-grained and drusy mosaic calcite. Echinoderms are overgrown by syntaxial calcite. Bioclastic-intraclastic grainstone This microfacies interchanges with peloid-filament-radiolarian packstone in wide laminae. Texture is homogenous. Grains represent 80 % of the area; intergranular space is filled by fine-grained, locally drusy mosaic calcite cement. Sorting is poor. Grains are mostly in point or long contacts. Grains range from 0.06 to 1.55 mm in size. Filaments and radiolarians strongly predominate (80 % of grains). Intraclasts, peloids and pellets are subordinate (10 % and 8 %, respectively). Very rare are ostracods and problematic algae. Peloid-intraclastic-bio- clastic grainstone with terrigenous admixture Texture is homogenous. Grains form 50 % of the area. Of these, terrigenous grains represent 20 % and allochems 30 %. Grains range 0.15–1 mm in size. They are moderately sorted. Small intraclasts and peloids are the most abundant among allochems. Approximately 5 % of the allochems are small bioclasts, which are partly or completely micritized. Benthic foraminifera (Palaeolituonella meridionalis (Luperto)) and echinoderms are recognisable. Terrigenous grains comprise chert, rhyolite-like volcanics, monocrystal quartz and plagioclase, and carbonate lithoclasts. Terrigenous grains are angular to very angular, between 0.15 mm and 0.55 mm in size. Plagioclase grains are partly sericitizied. Echinoderm plates are overgrown by syntaxial calcite cement. Bioclastic-intraclastic rudstone Texture is homogenous. Grains form 80 % of the area. They are very poorly sorted and measure 1 mm to 18.5 mm in size [within the thin section; several cm large clasts were observed in the field]. Subrounded clasts dominate. Grains are in stylolitic contacts. Allochems are dominated by intraclasts (oolithic packstone, wackestone with radiolarians and filaments, peloidal-bioclastic packstone, mudstone). Subordinate are echinoderm plates, ooids, peloids, benthic foraminifera and bivalve shells. Lithic grains are represented by recrystallised limestone. Other terrigenous grains are monocrystal quartz, plagioclase, and chert. These grains are angular to subangular, up to 5 mm large. The intergranular space is filled with spar. Silicification is locally present. Table 2. Limestone microfacies types from Middle Triassic beds between Mišji Dol and Poljane pri Primskovem. 113 Microfossils from Middle Triassic beds near Mišji Dol, central Slovenia Fig. 4. Selected microfacies types and microfossils from Middle Triassic beds between Mišji Dol and Poljane pri Primskovem. a: Interchang - ing laminae of radiolarian-filament wackestone/packstone and peloid-filament-radiolarian packstone. Thin section 1758 (sample MD1A:B). b: Radiolarian-filament wackestone-packstone. Thin section 1790 (sample MD5A:A). c: Bioclastic-peloid grainstone. Thin section 1763 (sample MD1A:C). d: Peloid-intraclastic-bioclastic grainstone with terrigenous admixture. Note foraminifer Palaeolituonella meridionalis (Luperto) in the centre. Thin section 1796 (sample MD7F:B). e: Variostoma sp. (right) and Ophthalmidium sp. (left) in bioclastic-peloid grainstone. Thin section 1763 (sample MD1A:C). f: Volcaniclastic sandstone. Thin section 1766 (sample MD1C:B). g: Endotriadella sp. in bioclastic-peloid grainstone. Thin section 1763 (sample MD1A:C). h: Endoteba sp. in bioclastic-peloid grainstone. Thin section 1763 (sample MD1A:C). i: Plexoramea cerebriformis Mello in bioclastic-peloid grainstone. Thin section 1786 (sample MD8A:A). 114 Katja OSELJ, Tea KOLAR-JURKOVŠEK, Bogdan JURKOVŠEK & Luka GALE Carbonate microfacies The textures and composition of the limestone samples are described in more detail in Table 2. Selected microfacies types and microfossils from thin sections are shown in Figure 4. Microfossil assemblage The microfossil assemblage from the residue consists of conodonts, benthic foraminifera, gas- tropods, echinoderms, brachiopods, green algae, radiolarians, microproblematica, and ostracods. A total of 16 conodont taxa were determined (Fig. 5): Fig. 5. Conodont taxa from Middle Triassic beds between Mišji Dol and Poljane pri Primskovem. SEM images. 1 – Budurovignathus sp., juvenile specimen, sample MD 6B:A (GeoZS 6260). 2 – Budurovignathus sp., sample MD 7F:A (GeoZS 6263). 3 – Paragondolella excelsa Mosher, sample MD 1J (GeoZS 6251). 4 – Paragondolella sp., juvenile specimen, sample MD 1B komp 0–0.25 (GeoZS 6247). 5 – Neogon- dolella cornuta Budurov & Stefanov, sample MD 1B komp 0–0.25 (GeoZS 6247). 6 – Paragondolella ex gr. trammeri (Kozur), sample MD 1J (GeoZS 6251). 7–9 – Paragondolella trammeri (Kozur), sample MD 5B:B (GeoZS 6258). 10 – Paragondolella trammeri (Kozur), samples MD 6C:A and MD 6D:A (GeoZS 6261). 11 – Paragondolella ex gr. trammeri (Kozur), samples MD 7E:A and MD 7E:B (GeoZS 6262). 12 – Budurovignathus gabrielae Kozur, sample MD 6B:A (GeoZS 6260). 13, 15 – Paragondolella ex gr. excelsa Mosher, sample MD 5D:A (GeoZS 6259). 14 – Paragondolella liebermani (Kovacs & Kozur), sample MD 5B:B (GeoZS 6258). 16 – Neogondolella balkanica Budurov & Stefanov, sample MD 5D:A (GeoZS 6259). Scale bar: 200 µm; a – upper, b – lateral, c – lower, d – oblique lower views. 115 Microfossils from Middle Triassic beds near Mišji Dol, central Slovenia Budurovignathus gabrielae Kozur (Fig. 5.12), Bu- durovignathus sp. (Fig. 5.1–5.2), Cratognathodus kochi (Huckriede), Gladigondolella malayensis Nogami, G. tethydis Huckriede, Gladigondolella sp., Neogondolella balkanica Budurov & Stefanov (Fig. 5.16), N. cf. excentrica Budurov & Stefanov, N. constricta (Mosher & Clark), N. cornuta Bu- durov & Stefanov (Fig. 5.5), Neogondolella sp., Paragondolella excelsa Mosher and P. ex gr. excel- sa (Fig. 5.3, 5.13, 5.15), P. liebermani (Kovacs & Kozur) (Fig. 5.14), P. trammeri (Kozur) and P. ex gr. trammeri (Fig. 5.6–5.11), P. cf. alpina (Kozur & Mostler), and Paragondolella sp. (Fig. 5.4). Ju- veniles dominate, while adult specimens are most- ly fragmented. Conodont elements are black and have a Colour Alteration Index (CAI) of 5.5 (Ep - stein et al., 1977). The foraminiferal assemblage is relatively sparse, except for a high number of Nodobacular- ia? vujisici Urošević & Gaździcki recovered from the residue of dissolved limestone from the low- er part of the succession (sector 2; see Table 1). Ophthalmidium exiguum Koehn-Zaninetti and very rare Pseudonodosaria sp. were present in the same sample. Along with the mentioned spe- cies, foraminifera include sessile agglutinated foraminifera, Palaeolituonella meridionalis (Lu- perto), Glomospirella sp., Endoteba sp., Endotri- adella sp., Krikoumbilica sp., Variostoma sp., Duostominidae, and small Lagenida. All were determined from thin sections. A taxonomic de- scription of Nodobacularia? vujisici Urošević & Gaździcki, which is a rarely noted species, is given below. Fig. 6. Nodobacularia? vujisici Urošević & Gaździcki from Middle Triassic beds between Mišji Dol and Poljane pri Primskovem. a: The same specimen viewed in reflected light (a1), immersed in glyceryl (a2), under SEM (a3), and in thin section (a4). b–f: Different specimens showing variability in size and length of the chambers. g: Detail of the wall seen under SEM. All specimens are from sample MD1B (GeoZS 4268). 116 Katja OSELJ, Tea KOLAR-JURKOVŠEK, Bogdan JURKOVŠEK & Luka GALE Subphylum Foraminifera d’Orbigny, 1826 Class Tubothalamea Pawlowski et al., 2013 Order Miliolida (Delage & Hérouard, 1896), emend Pawlowski et al., 2013 Superfamily Cornuspiroidea Schultze, 1854 Family Nubeculariidae Jones in Griffith and Hen- frey, 1875 Subfamily Nodobaculariinae Cushman, 1927 Genus ?Nodobacularia Rhumbler, 1895 Nodobacularia? vujisici Urošević & Gaździcki, 1977 Fig. 6a–g 1977 Nodobacularia vujisići nov. sp., Urošević & Gaździcki, p. 97, pl. 1, fig. 1–6. 1980 Nodophthalmidium elenae n.sp., Gheorghi- an, p. 38, pl. 1, fig. 1–11; pl. 2, fig. 1–6; pl. 3, fig. 1–2. 1983 Nodobacularia vujisići Urošević et Gaźd- zicki, 1977 – Salaj et al., p. 113, pl. 141, fig.1–2. 1984 Nodophthalmidium vujisici (Urošević & Gazdzicki, 1977) – Kristan-Tollmann, p. 285, fig. 8.1–8.7; pl. 11, fig. 1–29; pl. 8, fig. 9. 1987 Nodobacularia vujisici Urošević et Gaźd. – Oravecz-Scheffer, pl. 31, fig. 4. 1988 Nodophthalmidium vujisici Urošević et Gaździcki – Salaj et al., pl. 3, fig. 25, 26, 34. 1991 Nodobacularia vujisici Urošević et Gaździcki – Kolar-Jurkovšek, pl. 2, fig. 3–4. 1993 Gheorghianina vujisici (Urošević & Gaźd - zicki, 1977) – Trifonova, p. 50, pl. 8, fig. 1–2. 1996 Gheorghianina vujisici (Urosevic et Gazd- zicki, 1977) – Bérczi-Makk, p. 435, pl. 1, fig. 6–7. Material: Approximately 500 isolated spec- imens from the residue of radiolarian-filament wackestone/packstone from the bottom of sector 2 (Sample MD1B; GeoZS 4268; see Table 1). Description: The foraminiferal test is free, un- attached, and very elongated. Ovoid proloculus (diameter 0.018 mm, length 0.032 mm) is followed by two (?) elongated tubular chambers. The first of these is one-half of the whorls long, and shaped like in Ophthalmidium. The second chamber leads to a rectilinear or curvilinear part of the test, which consists of up to four elongated chambers. These are pyriform or flask-like in shape, but with the largest constriction two-thirds of the way up the chamber, so that the chamber again gains in width towards the simple circular aperture. The third chamber in the uniserial part measures ap- proximately 0.041–0.054 mm in width and 0.135– 0.230 mm in length. Although both, the length and width of the chambers increase continuously, they do so at different and inconstant rates. How- ever, since the chambers are always much longer than they are wide, the test is always very elongat- ed and narrow. Specimens with three chambers in the linear part are between 0.39 and 0.63 mm long, whereas the specimens with four chambers in the linear part measure 0.40 to 0.695 mm in length. The largest length of the chamber is 0.31 mm. The widest (usually third or fourth) chamber in the lin- ear part is usually equal in width to the planispiral part. However, deviations are possible in both di- rections. The wall is silicified. Remarks: The first description of N. vujisi- ci was based on specimens in the thin sections, and was originally thought to have lived fixed to a substrate. It was also interpreted that the plani - spiral part, which follows the proloculus, consists of a single tubular chamber, which later straight- ens up to form the initial part of the linear series of chambers (Urošević & Gaździcki, 1977). The new species was placed in the genus Nodobacu- laria, which, however, is characterised by two chambers in the planispiral part, and has some agglutinated particles within its wall (Loeblich & Tappan, 1988). Gheorghian (1980) later intro- duced two new species from the Middle and Up- per Triassic of Romania, with both attributed to the genus Nodophthalmidium Macfayden, 1939; of these species, Nodophthalmidium elenae Gheo- rghian represents a junior synonym of N. vujisici, but Nodophthalmidium anae Gheorghian repre- sents a distinct species characterised by longitu- dinal costae. Gheorghian (1980, pl. 2) provided hand-drawings of the specimens, showing a tubu- lar second chamber, that completely envelops the proloculus and continues to the linear part of the test. These illustrations led Loeblich and Tappan (1986) to establish a new genus, Gheorghianina, that differs from Nodobacularia in the mentioned feature, and from Nodophthalmidium in having more elongated chambers and a simple circular aperture. Both valid species, Nodobacularia vuji- sici, and Nodophthalmidium anae were attributed to this genus. However, we believe that the micro- photograph in Gheorghian’s (1980) plate 3 shows two chambers in the planispiral part, and that the second chamber is only one-half of a whorl long. Trifonova (1993) also noted that there are two chambers in the planispiral part of Nodobacularia vujisici and Nodophthalmidium anae. Moreover, this observation can be confirmed in the speci- mens from Mišji Dol. Bérczi-Makk (1996) stat- ed that Gheorghianina possesses a long, tapered neck, which is absent in both Nodobacularia and 117 Microfossils from Middle Triassic beds near Mišji Dol, central Slovenia Nodophthalmidium. Bérczi-Makk (1996) still con- sidered Gheorghianina to have a planispiral part one-chamber long, and also stated that the plani- spiral part is much smaller in Gheorghianina than in the other two genera. Whatever the generic assignment, Gheorghi- anina has been reported from the literature quite rarely. This could also be due to its small size and the brittle nature of its test. Imperfect sections could lead to confusion with Earlandia amplimu- ralis (Pantić). Salaj et al. (1983) described another species, Nodobacularia cylindriformis Salaj, Borza & Samuel, from Anisian beds, which lacks costae but is otherwise similar to N. anae. On the same plate, they figured also Nodophthalmidium cylin- driformis n. sp. (perhaps a misnomer for Nodob- acularia cylindriformis), creating some confusion, as no description is given under this name. Nodo- bacularia? vujisici is often found in facies with daonellids or some undetermined thin-shelled bi- valves (Urošević & Gaździcki, 1977; Gheorghian, 1980; Kristan-Tollmann, 1984; Kolar-Jurkovšek, 1991). Stratigraphic range: Illyrian to upper Carni - an of Carpathians; Ladinian of Himalayas; Lad- inian of Transdanubian Range and the Alsó Hill in Hungary; lower Ladinian to Carnian of Balkan Mountains and Dobrogea; and upper Anisian and Ladinian of Slovenia. Discussion Biostratigraphy and comparison with other conodont assemblages All of the studied conodont samples are marked by P. excelsa that is present throughout the sam- pled succession. This species is accompanied by G. tethydis, N. cornuta and N. constricta that oc- cur in most samples, except in the three samples from the uppermost part of the succession. Para- gondolella excelsa ranges from the Illyrian to the Fassanian (Chen et al., 2015). The species N. con- stricta ( se ns u K o zur ) , ran g es in th e Ill yrian , an d possibly even in the Pelsonian; N. cornuta, with a distinct cusp fused with the posterior platform end, is also common in the Illyrian faunas (Kozur et al., 1994). The upper part of the section is marked by the first occurrence of G. malayensis. Moreover, a successive appearance of N. cf. excentrica, P. lieb- ermani, N. balkanica and P. cf. alpina is noted in this zone; all of these species range in the Illyrian and the Fassanian (Chen et al., 2015). Moreover, an introduction of budurovignathids is notewor- thy. They first appear in the sample MD6B:A, from which a single specimen of B. gabrielae is deter- mined. It reveals a slightly sigmoidal platform, bent, and a forward shifted basal cavity. This spe- cies was first described from the upper Fassanian of Karavanke, Southern Alps, and was interpreted to be the oldest Budurovignathus representative as it retained some features of Neogondolella, i.e., broadly rounded platform end and relatively sep- arated carina denticles (Kozur et al., 1994). The Budurovignathus specimens from the uppermost part of the section are more advanced, having typical high carina with fused denticles, as well as significant sigmoidal bending and thus a for- ward-shifted basal cavity. The specimens of P. trammeri predominate in the faunas of the upper part of the section. Juve- nile and intermediate forms prevail over adults. It should be noted here that some other taxa ( P. eotrammeri Krystyn, P. preaetrammeri (Kozur)) were described from the P. trammeri group, where only adult specimens can be distinguished among each other. For a long time, P. trammeri was one of the most important Ladinian markers found in open pelagic and more restricted settings of the Tethys. Based on the composition of the faunas, two conodont zones can be distinguished. The older is the constricta Zone that encompasses the interval from the sample MD1B to the sample MD2A:A. The zonal marker N. constricta is accompanied by C. kochi, G. tethydis, N. cornuta, P. excelsa, P. ex gr. trammeri (juvenile), and Paragondolella sp. The range of this zone in Slovenia is lower Illyrian (Kolar-Jurkovšek & Jurkovšek, 2019). Upward follows the trammeri Zone. It is char - acterized by the index species in association with some holdover species from the previous zone, which are G. tethydis, N. cornuta, N. constricta, and P. excelsa. The lower boundary of this zone is identified by the first appearance of G. malayensis in the sample MD2E:A. Other species that are in- troduced in this zone are: B. gabrielae, N. balkan- ica, N. cf. excentrica, P. liebermani, P. cf. alpina. The trammeri zone in Slovenia ranges from the upper Illyrian to the lower Fassanian (Kolar-Jurk - ovšek & Jurkovšek, 2019). The colour of the cono- dont elements suggests that the rocks were sub- jected to temperatures between 300 °C and 550 °C (Epstein et al., 1977). The conodont assemblage from the Mišji Dol section is similar to the assemblage recorded from Bagolino in the Southern A lps of the northern Italy, the GSSP for the Ladinian (Brack & Nicora, 1998; Brack et al., 2005). The similarity is especially 118 Katja OSELJ, Tea KOLAR-JURKOVŠEK, Bogdan JURKOVŠEK & Luka GALE Mišji Dol Topla Prisojnik Kamna Gorica Idrijske Krnice Šentjošt Hrastenice Šmarna gora Jagršče Rižnikar Rob & Ortnek Bučka Sremič Loke No. Budurovignathus sp. • • • 3 Budurovignathus gabrielae Kozur • 1 B. hungaricus Kozur • • 2 B. mirautae (Kovacs) • 1 B. mungoensis (Diebel) • 1 Cratognathodus kochi (Huckriede) • • 2 Gladigondolella malayensis Nogami • • 2 G. tethydis Nogami • • • • • 5 Gondolella hanbulogi (Sudar & Budurov) • 1 Neogondolella balkanica Budurov & Stefanov • • 2 N. bifurcata (Budurov & Stefanov) • 1 N. bulgarica (Budurov & Stefanov) • • 2 N. constricta (Mosher & Clark) • • • • • 5 N. cornuta Budurov & Stefanov • • • • • 5 N. excelsa (Mosher) • • • 3 N. excentrica Budurov & Stefanov • • • 3 N. mombergensis (Tatge) • • 2 N. transita (Kozur & Mostler) • • 2 Paragondolella alpina (Kozur & Mostler) • • • 3 P . excelsa Mosher • • • • • 5 P . liebermani (Kovacs & Kozur) • 1 P . navicula (Huckriede) • • 2 P. prealpina Ramovš & Goričan • • 2 P .? pridaensis posteroacuta Kozur, Krainer & Mostler • • 2 P . trammeri (Kozur) • • • • • • 6 P . praeszaboi bystricky Kovács et al. • 1 Total no. species at locality: 13 4 4 1 6 1 5 6 2 7 4 3 5 4 Table 3. Illyrian – Fassanian conodont assemblages from Slovenia (based on Kolar-Jurkovšek & Jurkovšek, 2019). Localities Slugovo and Rižnikar feature slightly younger, late Fassanian, and Fassanian – Longobardian assemblages, respectively. 119 Microfossils from Middle Triassic beds near Mišji Dol, central Slovenia evident for the elements belonging to the latest Anisian constricta zone, and in the presence of budurovignathids in the Ladinian part. Eight taxa are common to both sections: N. balkanica, N. constricta, N. cornuta, P. excelsa, P. liebermani, P. trammeri, P. ex gr. alpina, and G . malayensis . Their occurrence is similar in both sections. It should be noted here that different taxonomies have been used for the determination of some ne- ogondolellids, and in Bagolino some of them were determined at subspecies level: N. constricta cor- nuta Budurov & Stefanov, N. constricta postcor- nuta (Kovacs), N. constricta balkanica Budurov & Stefanov (Brack & Nicora, 1998). The lower part of the reitzi Zone in the Bagolino section yields N. constricta, N. cornuta and P. excelsa that can be compared to the lower part of the Mišji Dol section belonging to the constricta Zone. The upper part of the reitzi Zone and the secedensis Zone of the Bagolino section is marked by the appearance of G. malayensis and P. trammeri; this part is also characterized by the occurrence of the precursor of B. gabrielae, determined as N. sp. A, whereas ear- ly budurovignathids are represented by three taxa in the Ladinian part of the section. The difference between the composition of the faunas in the two sections is the earlier appearance of P. lieberma- ni in the Bagolino section, where P. ex gr. alpina is present in most of the Anisian part of the sec- tion and continues also in the curionii Zone; in the Mišji Dol section, P. ex gr. alpina is very rare and has been encountered only in the trammeri Zone. Based on the conodont faunas the age of the studied section thus is Illyrian-Fassanian. Exact position of the base of the trammeri zone cannot be determined based on the recovered material, but it is tentatively marked by the first occurrence of G. malayensis. The Anisian-Ladinian bound- ary could be therefore placed between samples MD2E:A and MD4A:A, most probably after the fa- cies change within the sector 18 (Fig. 3). The fau- na of the upper part of the trammeri zone reveals Ladinian character due to the presence of budu- rovignathids. In the studied Mišji Dol section they are first encountered approximately 20 m above the occurrence of G. malayensis, whereas in the Bagolino section budurovignathids (B. truempyi, B. hungaricus) occur in the layers corresponding the Ladinian level (Brack et al., 2005). Table 3 lists other localities from Slovenia with common conodont species from the Illyri - an – Fassanian interval (see Kolar-Jurkovšek and Jurkovšek, 2019 for an overview of the localities and existing references). These successions were deposited in different palaeogeographic situations Mišji Dol Topla Prisojnik Kamna Gorica Šentjošt Hrastenice Šmarna gora Jagršče Rižnikar Rob & Ortnek Bučka Sremič Loke Idrijske Krnice Mišji Dol 1 0.24 0.35 0.14 0 0.33 0.42 0.13 0.3 0.35 0.25 0.44 0.11 0.21 Topla 0.24 1 0 0 0 0.22 0.2 0 0 0 0 0.22 0.4 0.2 Prisojnik 0.35 0 1 0.4 0 0 0.4 0 0.18 0.25 0 0 0 0 Kamna Gorica 0.14 0 0.4 1 0 0 0.29 0 0.25 0.4 0 0 0 0 Šentjošt 0 0 0 0 1 0 0 0 0 0 0.5 0 0.29 0.29 Hrastenice 0.33 0.22 0 0 0 1 0.73 0 0.17 0 0.25 0.4 0.18 0 Šmarna gora 0.42 0.2 0.4 0.29 0 0.73 1 0 0.31 0.2 0.22 0.18 0.17 0 Jagršče 0.13 0 0 0 0 0 0 1 0.22 0 0.4 0 0 0.5 Rižnikar 0.3 0 0.18 0.25 0 0.17 0.31 0.22 1 0.36 0.2 0 0 0.15 Rob & Ortnek 0.35 0 0.25 0.4 0 0 0.2 0 0.36 1 0 0.44 0 0 Bučka 0.25 0 0 0 0.5 0.25 0.22 0.4 0.2 0 1 0 0.44 0.44 Sremič 0.44 0.22 0 0 0 0.4 0.18 0 0 0.44 0 1 0 0 Loke 0.11 0.4 0 0 0.29 0.18 0.17 0 0 0 0.44 0 1 0.17 Idrijske Krnice 0.21 0.2 0 0 0.29 0 0 0.5 0.15 0 0.44 0 0.17 1 Table 4. The Dice similarity index for different localities with latest Anisian – earliest Ladinian conodont assemblages in Slovenia (based on Kolar-Jurkovšek & Jurkovšek, 2019). 120 Katja OSELJ, Tea KOLAR-JURKOVŠEK, Bogdan JURKOVŠEK & Luka GALE Budurovig- nathus sp. B.mirautae B.gabrielae B.hungaricus B.mungoensis C.kochi G.malayensis Go.hanbulogi G.tethydis N.balkanica N.bifurcata N.bulgarica N.constricta N.cornuta N.excelsa N.excentrica N.mombergensis N.transita P .alpina P .excelsa P .liebermani P .navicula P .prealpina P .pridaensis P .trammeri P .praeszaboi Budurovig- nathus sp. 1 0 0.5 0.4 0 0.8 0.4 0 0.25 0.4 0 0 0.25 0.5 0 0.33 0 0.4 1 0.3 0.5 0 0 0 0.44 0 B.mirautae 0 1 0 0.67 1 0 0 0 0.33 0 0 0 0 0 0 0 0 0 0 0.4 0 0 0 0 0.29 1 B.gabrielae 0.5 0 1 0 0 .67 0.67 0 0.33 0.67 0 0 0.33 0.33 0 0.5 0 0 0.5 0.4 1 0 0 0 0.29 0 B.hungaricus 0.4 0.67 0 1 0.67 0 0 0 0.29 0 0 0 0 0 0 0 0 0 0.4 0.33 0 0 0 0 0.5 0.67 B.mungoensis 0 1 0 0.67 1 0 0 0 0.33 0 0 0 0 0 0 0 0 0 0 0.4 0 0 0 0 0.29 1 C.kochi 0.8 0 0.67 0 0 1 0.5 0 0.29 0.5 0 0 0.29 0.57 0 0.4 0 0.5 0.8 0.33 0.67 0 0 0 0.25 0 G.malayensis 0.4 0 0.67 0 0 0.5 1 0 0.29 1 0 0 0.29 0.29 0 0.4 0 0 0.4 0.33 0.67 0 0 0.5 0.5 0 Go.hanbulogi 0 0 0 0 0 0 0 1 0.33 0 1 0.67 0 0 0.4 0.5 0 0 0 0 0 0 0 0 0 0 G.tethydis 0.25 0.33 0.33 0.29 0.33 0.29 0.29 0.33 1 0.29 0.33 0.57 0.4 0.2 0.44 0.5 0 0 0.25 0.44 0.33 0 0 0 0.36 0.33 N.balkanica 0.4 0 0.67 0 0 0.5 1 0 0.29 1 0 0 0.29 0.29 0 0.4 0 0 0.4 0.33 0.67 0 0 0.5 0.5 0 N.bifurcata 0 0 0 0 0 0 0 1 0.33 0 1 0.67 0 0 0.4 0.5 0 0 0 0 0 0 0 0 0 0 N.bulgarica 0 0 0 0 0 0 0 0.67 0.57 0 0.67 1 0 0 0.33 0.4 0 0 0 0 0 0 0 0 0 0 N.constricta 0.25 0 0.33 0 0 0.29 0.29 0 0.4 0.29 0 0 1 0.6 0.44 0.25 0.29 0.29 0.25 0.67 0.33 0.29 0.57 0.29 0.36 0 N.cornuta 0.5 0 0.33 0 0 0.57 0.29 0 0.2 0.29 0 0 0.6 1 0 0.5 0.29 0.57 0.5 0.67 0.33 0.29 0.57 0.29 0.36 0 N.excelsa 0 0 0 0 0 0 0 0.4 0.44 0 0.4 0.33 0.44 0 1 0.29 0.33 0 0 0 0 0.33 0 0 0 0 N.excentrica 0.33 0 0.5 0 0 0.4 0.4 0.5 0.5 0.4 0.5 0.4 0.25 0.5 0.29 1 0.4 0 0.33 0.29 0.5 0.4 0 0 0.22 0 N.momber- gensis 0 0 0 0 0 0 0 0 0 0 0 0 0.29 0.29 0.33 0.4 1 0 0 0 0 1 0 0 0 0 N.transita 0.4 0 0 0 0 0.5 0 0 0 0 0 0 0.29 0.57 0 0 0 1 0.4 0.33 0 0 0.5 0 0 0 P .alpina 1 0 0.5 0.4 0 0.8 0.4 0 0.25 0.4 0 0 0.25 0.5 0 0.33 0 0.4 1 0.29 0.5 0 0 0 0.44 0 P .excelsa 0.29 0.4 0.4 0.33 0.4 0.33 0.33 0 0.44 0.33 0 0 0.67 0.67 0 0.29 0 0.33 0.29 1 0.4 0 0.67 0.33 0.6 0.4 P .liebermani 0.5 0 1 0 0 0.67 0.67 0 0.33 0.67 0 0 0.33 0.33 0 0.5 0 0 0.5 0.4 1 0 0 0 0.29 0 P .navicula 0 0 0 0 0 0 0 0 0 0 0 0 0.29 0.29 0.33 0.4 1 0 0 0 0 1 0 0 0 0 P .prealpina 0 0 0 0 0 0 0 0 0 0 0 0 0.57 0.57 0 0 0 0.5 0 0.67 0 0 1 0.5 0.25 0 P .pridaensis 0 0 0 0 0 0 0.5 0 0 0.5 0 0 0.29 0.29 0 0 0 0 0 0.33 0 0 0.5 1 0.5 0 P .trammeri 0.44 0.29 0.29 0.5 0.29 0.25 0.5 0 0.36 0.5 0 0 0.36 0.36 0 0.22 0 0 0.44 0.6 0.29 0 0.25 0.5 1 0.29 P .praeszaboi 0 1 0 0.67 1 0 0 0 0.33 0 0 0 0 0 0 0 0 0 0 0.4 0 0 0 0 0.29 1 Table 5. The Dice similarity index for the correlation among the determined conodont taxa. 121 Microfossils from Middle Triassic beds near Mišji Dol, central Slovenia and presently belong to different structural units. The conodont assemblage from Prisojnik, Šentjošt, Hrastenice, Šmarna gora, Sremič, Idrijske Krnice, and Bučka derive from red nodular limestone de - posited within smaller grabens on top of a drowned upper Anisian carbonate platform. Successions from Kamna Gorica, Jagršče, Rižnikar, Rob and Ortnek, and Loke are lithologically more similar to the succession at Mišji Dol, namely featuring grey hemipelagic limestone in association with volcan- iclastics and marlstone. The succession from Topla comprises bedded limestone with chert. It must be reminded that samples were (at least partly) col- lected by different authors, at different times, and that the size of the exposures and the number of collected samples vary as well. In addition, assem - blages from Hrastenice, Loke and Idrijske Krnice represent only one conodont zone (constricta), section at Kamna Gorica only spans Fassanian, whereas sections at Rižnikar, Rob and Ortnek contain elements from the trammeri, as well as the succeeding hungaricus zones. The diversity of the conodont assemblages from these localities is generally low to moderate (Kolar-Jurkovšek & Ju- rkovšek, 2019). The diversity and composition of the conodont assemblages seems unrelated to the lithological composition of the sampled sites. Based on the current data and without regard for the is- sues mentioned above, the assemblage from Mišji Dol has a notably more diverse range of conodonts (13 species) than other sampled assemblages. The beta diversity of the conodont assemblages seems rather large, since only five species are present in a significant number of sampling sites: out of 14, Paragondolella trammeri has been found at 6 localities, and Gladigondolella tethydis, Neogon- dolella constricta, N. cornuta and Paragondolella excelsa at 5 localities. Consequently, the similarity between localities is relatively low (Table 4). The largest similarity can be found between the local- ities of Šmarna gora and Hrastenice (Dice index 0.73), the first being late Anisian – early Ladini- an in age, the latter late Anisian. The assemblage from Mišji Dol is most similar to the assemblages from Sremič and Šmarna gora (Dice indices 0.44 and 0.42, respectively), both spanning the same, late Anisian – early Ladinian time interval. Table 5 shows correlation among species. Some of the species seem to associate (e.g., Paragon- dolella alpina and Budurovignathus sp., Paragon- dolella liebermani and Budurovignathus gabrielae, Neogondolella mombergensis and Paragondolella navicula; Table 5), which indicates that they had similar ecological preferences. However, said cor- relation would be more reliable if it were based on data obtained from samples of the same weight and collected in a similar density. The correlation also cannot be confirmed for the pairs of species that are listed in the Table 5 only once, for example Budurovignathus mungoensis, Budurovignathus mirautae and Paragondolella praeszaboi, Neogon- dolella balkanica and Neogondolella bifurcata. Depositional environment The investigated succession roughly consists of segments, in which there is a variable mixture of lithologies, namely the thin-bedded limestone, marlstone, tuff and volcaniclastic sandstone, and segments that are dominated by thin- to medi- um-thick beds of carbonates (limestone and/or do- lostone). The first are attributed to times of more intense volcanic activity and/or deposition in a more distal part of the basin, while the latter in- dicate periods of substantial platform production and export of the material down-slope to the more proximal parts of the basin, and/or periods of the quiescence of volcanic activity. The mudstone and radiolarian-filament wackestone-packstone pres- ent background hemipelagic/pelagic sedimenta- tion. Other microfacies types are interpreted as sediments of distal (in the case of rudstone also more proximal) turbidity currents, which brought some platform-derived material (biogenic grains with micritised margins, green algae) into the ba- sin and mixed it with components characteristic for open-marine waters (e.g., radiolarians, thin- shelled bivalves). The volcaniclastic sandstone also results from mass flow deposition, but the source of the material was volcanic rocks or tuff layers. The paleogeographic extent of the basin cannot be determined, but numerous smaller basins with a similar type of sedimentation can be envisioned for the late Anisian – early Ladinian for the Ex- ternal Dinarides (e.g., Kolar-Jurkovšek, 1983; Ju- rkovšek, 1983; Kolar-Jurkovšek, 1991; Demšar & Dozet, 2003; Čar, 2010; Kocjančič et al., 2022). Conclusions A succession of marlstone, tuff, volcaniclastic sandstone, and thin- to medium-bedded limestone and dolostone between Mišji Dol and Poljane pri Primskovem contains a relatively rich assemblage of conodonts of the lower Illyrian constricta Zone and the upper Illyrian to lower Fassanian tram- meri Zone. The associated foraminifera include numerous representatives of the species Nodoba- cularia? vujisici Urošević & Gaździcki. The cono - dont assemblage is similar to the assemblage re- corded from Bagolino in northern Italy. On the other hand, assemblages from other localities in 122 Katja OSELJ, Tea KOLAR-JURKOVŠEK, Bogdan JURKOVŠEK & Luka GALE Slovenia have few taxa in common, which is in ac- cordance with the presence of numerous smaller basins characterised by different conditions and communities. Acknowledgements The presented paper is the result of the master thesis written by the first author (K. Oselj). The thesis was defended at the Department of Geology, Faculty of Nat- ural Sciences and Engineering. Preparation of the ma- terial and the field work was financed by the Slovenian Research Agency (research core funding No. P1-0011; authors T. Kolar-Jurkovšek, B. Jurkovšek and L. Gale). Thin sections were prepared and the microfossils were photographed at the Geological Survey of Slovenia. We thank the reviewers for the thorough reading of the manuscript and constructive remarks. References Bérczi-Makk, A. 1996c: Foraminifera of the Tri- assic formations of Alsó Hill (Northern Hun- gary). Part 3: Foraminifer assemblage of the basinal facies. Acta Geol. Hungarica, 39/4: 413–459. Berra, F. & Carminati, E. 2010: Subsidence history from a backstripping analysis of the Permo- Mesozoic succession of the Central Suth- ern Alps (northern Italy). Basin Res., 22/6: 952–975. https://doi.org/10.1111/j.1365- 2117 .2009.00453.x Brack, P. & Nicora, A. 1998: Conodonts from the Anisian-Ladinian succession of Bagolino, Brescian Prealps (Brescia, Lombardy, North- ern Italy). Giornale Geol., 60/3: 314–325. Brack, P., Rieber, H., Nicora, A. & Mundil, R. 2005: The Global boundary Stratotype Section and Point (GSSP) of the Ladinian Stage (Middle Triassic) at Bagolino (Southern Alps, Northern Italy) and its implications for the Triassic time scale. Episodes, 28/4: 233–244. ht t p s://doi . org/10.18814/epiiugs/2005/v28i4/001 Budai, T. & Vörös, A. 2006: Middle triassic plat- form and basin evolution of the Southern Bakony mountains (Transdanubian Range, Hungary). Riv. Ital. Paleontol. Strat., 112/3: 359–371. https://doi.org/10.13130/2039- 4942/6346 Buser, S. 1969: Osnovna geološka karta SFRJ 1: 100 000. List Ribnica. Zvezni geološki zavod, Beograd. Buser, S. 1974: Osnovna geološka karta SFRJ 1: 100 000. Tolmač lista Ribnica. Zvezni geološki zavod, Beograd: 60 p. Buser, 1986: Osnovna geološka karta SFRJ 1: 100 000. Tolmač za lista Tolmin in Videm (Udine). Zvezni geološki zavod, Beograd: 103 p. Buser, S. 1989: Development of the Dinaric and the Julian carbonate platforms and of the in- termediate Slovenian Basin (NW Yugoslavia). Boll. Soc. Geol. Ital., 40: 313–320. Celarc, B., Goričan, Š. & Kolar-Jurkovšek, T. 2013: Middle Triassic carbonate-platform break- up and formation of small-scale half-grabens (Julian and Kamnik-Savinja Alps, Slovenia). Facies, 59: 583–610. https://doi.org/10.1007/ s10347-012-0326-0 Chen, Y.L., Krystyn, L., Orchard, M.J., Ali, X.L. & Richoz, S. 2015: A review of the evolution, biostratigraphy, provincialism and diversity of Middle and early Late Triassic conodonts. Pap. Palaeontol., 2/2: 235–263. ht t p s://doi . org/10.1002/spp2.1038 Cushman, J.A. 1927: An outline of a re-classi- fication of the foraminifera. Contributions from the Cushman Laboratory for Foram. Res., 3: 1–105. https://doi.org/10.1126/sci- ence.65.1689.473.b Čar, J. 2010: Geological structure of the Idrija – Cerkno hills: Explanatory book to the Geolog- ical map of the Idrija – Cerkljansko hills be - tween Stopnik and Rovte 1: 25 000. Geological Survey of Slovenia, Ljubljana: 127 p. Čar, J. 2013: Ladinian skonca beds of the Idrija Ore Deposit (W Slovenia). Geologija, 56/2: 151–174. https://doi.org/10.5474/geologi- ja.2013.010 Čar, J., Jež, J. & Milanič, B. 2021: Structural set - ting at the contact of the Southern Alps and Di- narides in western Cerkljansko region (western Slovenia). Geologija, 64/2: 189–203. ht t p s:// doi.org/10.5474/geologija.2021.011 Delage, Y. & Hérouard, E. 1896: Traité de Zool- ogie Concrète, Volume 1, La Cellule et les Protozoaires. Schleicher Frères, Paris: 584 p. https://doi.org/10.5962/bhl.title.11672 Demšar, M. & Dozet, S. 2003: Anisian and Lad- inian beds in the cross-section above Srednik Valley at Križna Gora, central Slovenia. Ge - ologija, 46/1: 41–48. https://doi.org/10.5474/ geologija.2003.002 Di Capua, A., De Rosa, R., Kereszturi, G., Le Pera, E., Rosi, M. & Watt, S.F.L. 2022: Volcanic- ally-derived deposits and sequences: a uni- fied terminological scheme for application in modern and ancient environments. Geol. Soc. London, Spec. Publ., 520: 11–27. ht t p s://doi . org/10.1144/SP520-2021-201 123 Microfossils from Middle Triassic beds near Mišji Dol, central Slovenia Dozet, S. 2006: Ladinian beds in the Obla Gorica area, central Slovenia. RMZ – Mater. Geoenvi- ron., 53/3: 367–383. Dozet, S. & Buser, S. 2009: Triassic. In: Pleničar, M., Ogorelec, B. & Novak, M. (eds.): Geology of Slovenia. Geological Survey of Slovenia, Lju- bljana: 161–214. Dunham, R.J. 1962: Classification of carbonate rocks according to depositional texture. In: Han, W.E. (ed.): Classification of carbonate rocks, A symposium. American Ass. Petrol. Geol. Mem., Tulsa: 108–121. Embry, A.F. & Klovan, J.E. 1972: Absolute water depth limits of late Devonian paleoecological zones. Geol. Rundschau, 61: 672–686. ht t p s:// doi.org/10.1007/BF01896340 Epstein, A.G., Epstein, J.B. & Harris, L.D. 1977: Conodont colour alteration – an index to or- ganic metamorphism. Geol. Survey Am. Prof. Paper, 995: 1–27. Gawlick, H.-J., Goričan, Š., Missoni, S. & Lein, R. 2012: Late Anisian platform drowning and radiolarite deposition as a consequence of the opening of the Neotethys ocean (High Karst nappe, Montenegro). Bull. Soc. géol. France, 183: 349–358. https://doi.org/10.2113/gssgf- bull.183.4.349 Germovšek, C. 1955: O geoloških razmerah na prehodu Posavskih gub v Dolenjski kras med Stično in Šentrupertom. Geologija, 3: 116–135. Gheorghian, D. 1980: Note concernant quelques espèces de Nodophthalmidium dans le Trias Moyen-Supérieur de Roumanie. Dări de Seamă ale Şedinţelor, Institutul de Geologie si Geofi - zica, Paleontologie, 65/3: 37–41. Gianolla, P., Caggiati, M. & Pecorari, M. 2019: Looking at the timing of Triassic magmatism in the Southern Alps. Geo.Alp, 16: 65–68. Goričan, Š. & Buser, S. 1990: Middle Triassic radi - olarians from Slovenia (Yugoslavia). Geologija, 31–32 (1988/1989): 133–197. Griffith, J.W. & Henfrey, A. 1875: The micrograph- ic dictionary: a guide to the examination and investigation of the structure and nature of mi- croscopic objects. Van Voorst, London. Haas, J. & Budai, T. 1999: Triassic sequence stra- tigraphy of the Transdanubian Range (Hunga- ry). Geol. Carpathica, 50/6: 459–475. Hammer, Ø., Harper, D.A.T. & Ryan, P.D. 2001: PAST: Paleontological statistics software pack- age for education and data analysis. Palaeon- tol. electronica, 4/1: 1–9. Jurkovšek, B. 1983: Fassanian beds with daonel- las in Slovenia. Geologija, 26/1: 29–70. Jurkovšek, B. 1984: Langobardian beds with daonellas and posidonias in Slovenia. Geologi- ja, 27/1: 41–95. Kocjančič, A., Rožič, B., Gale, L., Vodnik, P., Kolar-Jurkovšek, T. & Celarc, B. 2022: Facies analysis of Ladinian and Carnian beds in the area of Rute Plateau (External Dinarides, cen- tral Slovenia). In: Rožič, B. & Žvab Rožič, P. (eds): 15th Emile Argand Conference on Alpine Geological Studies: 12–14 September 2022, Ljubljana, Slovenia: abstract book & fieldtrip guide. Faculty of Natural Sciences and Engi- neering, Department of Geology, Ljubljana: 37. https://doi.org/10.5194/egusphere-alp- shop2022-37 Kolar-Jurkovšek, T. 1983: Middle Triassic cono- donts from Slovenia. Rudarsko-metalurški zbornik, 30/4: 323–364. Kolar-Jurkovšek, T. 1991: Microfauna of Middle and Upper Triassic in Slovenia and its biostrati- graphic significance. Geologija, 33/1: 21–170. https://doi.org/10.5474/geologija.1990.001 Kolar-Jurkovšek, T. & Jurkovšek, B. 2019: Cono- donts of Slovenia. Geological Survey of Slove- nia, Ljubljana: 259 p. Kovács, S., Sudar, M., Grădinaru, E., Gawlick, H.- J., Karamata, S., Haas, J., Péro, C., Gaetani, M., Mello, J., Polák, J., Aljinović, D., Ogorelec, B., Kolar-Jurkovšek, T., Jurkovšek, B. & Buser, S. 2011: Triassic evolution of the tectonostrati- graphic units of the Circum-Pannonian Re- gion. Jb. Geol. B.-A., 151: 199–280. Kozur, H., Krainer, K. & Mostler, H. 1994: Mid- dle Triassic Conodonts from the Southern Karawanken Mountains (Southern Alps) and Their Stratigraphic Importance. Geol.-Paläon - tol. Mitt. Innsbruck, 19: 165–200. Kristan-Tollmann, E. 1984: Trias-Foraminiferen von Kumaun im Himalaya. Mitt. Österr. Geol. Ges., 77: 263–329. Lipold, M. 1858: Bericht über die geologische Auf- nahmen in Unter-Krain im Jahnre 1857. Jb. Geol. Reichsanst., 9/2: 257–276. Loeblich, A.R.Jr. & Tappan, H. 1986: Some new and redefined genera and families of Textular- iina, Fusulinina, Involutinina, and Miliolina (Foraminiferida). J. Foram. Res., 16/4: 334– 346. https://doi.org/10.2113/gsjfr.16.4.334 Macfayden, W.A. 1939: On Ophthalmidium, and two new names for Recent foraminifera of the family Ophthalmidiidae. J. Royal Microscop. Soc., 59: 162–169. Oravecz-Scheffer, A. 1987: Triassic foraminifers of the Transdanubian Central Range. Geol. Hun- garica, 50: 3–134. 124 Katja OSELJ, Tea KOLAR-JURKOVŠEK, Bogdan JURKOVŠEK & Luka GALE Orbigny, A. d’ 1826: Tableau méthodique de la classe des Céphalopodes. Ann. Sci. Natur., 7: 245–314. Pawlowski, J., Holzmann, M. & Tyszka, J. 2013: New supraordinal classification of Foraminif- era: Molecules meet morphology. Marine Mi- cropal., 100: 1–10. https://doi.org/10.1016/j. marmicro.2013.04.002 Placer, L. 1998a: Structural meaning of Sava Folds. Geologija, 41/1: 191–221. ht t p s://doi . org/10.5474/geologija.1998.012 Placer, L. 1998b: Contribution to the macrotec- tonic subdivision of the border region be- tween Southern Alps and External Dinar- ides. Geologija, 41/1: 223–255. ht t p s://doi . org/10.5474/geologija.1998.013 Placer, L. 2008: Principles of the tectonic subdi- vision of Slovenia. Geologija, 51/2: 205–217. https://doi.org/10.5474/geologija.2008.021 Rakovec, I. 1950: Pseudozilian strata in Slovenia (NW Yugoslavia). Geogr. Vestnik, 22: 1–24. Ramovš, A. & Goričan, Š. 1995: Late Anisian – Early Ladinian radiolarians and conodonts from Šmarna gora near Ljubljana, Slovenia. Razprave IV. razreda SAZU, 36/9: 179–221. Rhumbler, L. 1895: Entwurf eines naturlichen Systems des Thalamophoren. Nachrichten Ge- sell. Wiss. Göttingen, Math.-Physik, 1: 51–98. Rožič, B., Kocjančič, A., Gale, L., Popit, T., Žvab Rožič, P., Vodnik, P., Zupančič, N., Kolar-Ju - rkovšek, T. & Celarc, B. 2021: Arhitektura in sedimentarni razvoj ladinijskega bazena na območju Rutarske planote. Geol. zbornik, 26: 111–116. Salaj, J., Borza, K. & Samuel, O. 1983: Triassic foraminifers of the West Carpathians. Geol. ústav Dionýsa Štúra: 213 p. Salaj, J., Trifonova, E., Gheorghian, D. & Corone- ou, V. 1988: The Triassic foraminifera microbi- ostratigraphy of the Carpathian – Balkan and Hellenic realm. Mineralia slov., 20/5: 387–415. Schmid, S. M., Bernoulli, D., Fügenschuh, B., Ma- tenco, L., Schefer, S., Schuster, R., Tischler, M. & Ustaszewski, K. 2008: The Alpine-Carpathi- an-Dinaridic orogenic system: correlation and evolution of tectonic units. Swiss J. Geosci. (Geol. Rundsch.), 101/1: 139–183. ht t p s://doi . org/10.1007 /s00015-008-1247-3 Schultze, M.S. 1854: Über den Organismus der Polythalamien (Foraminiferen), nebst Ber- merkungen über die Rhizopoden im Allgemei- nen. Wilhelm Engelmann, Leipzig: 68 p. Skaberne, D., Goričan, Š. & Čar, J. 2003: Kam - nine in fosili (radiolariji) iz kamnoloma Kam- na Gorica. Vigenjc, glasilo Kovaškega muzeja v Kropi, 3: 85–96. Smirčić, D., A ljinov ić, D., Bar ud žija, U. & Kolar- Ju - rkovšek, T. 2020: Middle Triassic syntectonic sedimentation and volcanic influence in the central part of the External Dinarides, Croatia (Velebit Mts.). Geol. Quarterly, 64/1: 220–239. https://doi.org/10.7306/gq.1528 Stefani, M., Furin, S. & Gianolla, P. 2010: The changing climate framework and deposition- al dynamics of Triassic carbonate platforms from the Dolomites. Palaeogeogr., Palaeocli- matol., Palaeoecol., 290: 43–57. ht t p s://doi . org/10.1016/j.palaeo.2010.02.018 Tomljenović, B. & Csontos, L. 2001: Neogene–Qua - ternary structures in the border zone between Alps, Dinarides and Pannonian Basin (Hrvat- sko zagorje and Karlovac Basins, Croatia). Int. J. Earth Sciences (Geol. Rundsch.), 90: 560– 578. https:/ /doi.org/10.1007 /s005310000176 Trifonova, E. 1993: Taxonomy of Bulgarian Tri- assic foraminifera. II. Families Endothyriidae to Ophthalmidiidae. Geol. Balcanica, 23/2: 19–66. Urošević, D. & Gaździcki, A. 1977: Nodobacular- ia vujisici nov. sp. ladinskog kata unutrašn- jeg-karpatskog pojasa (istočna Srbija). Bull. Mus. Hist. Natur., Ser. A, 32: 97–101. Velledits, F., Péró, C., Blau, J., Senowbari-Daryan, B., Kovács, S., Piros, O., Pocsai, T., Szügyi-Si- mon, H., Dumitrică, P. & Pálfy, J. 2011: The oldest Triassic platform margin reef from the Alpine-Carpathian region (Aggtelek, NE Hun- gary): platform evolution, reefal biota and biostratigraphic framework. Riv. Ital. Pale - ontol. Stratigr., 117/2: 221–268. ht t p s://doi . org/10.13130/2039-4942/5973 Vrabec, M. & Fodor, L. 2006: Late Cenozoic tec- tonics of Slovenia: Structural styles at the northeastern corner of the Adriatic microplate. In: Pinter, N., Grenerczy, G., Weber, J., Stein, S. & Medek, D. (eds.): The Adria microplate: GPS geodesy, tectonics and hazards. NATO Sci. Ser., IV, Earth Environ. Sci., 61: 151–168. Medak, D. & Stein, S. (eds.): The Adria Microplate: GPS geodesy, tectonics and hazards. Kluwer Academic Publ.: 151–168. Wright, V.P. 1992: A revised classification of lime- stones. Sed. Geology, 76: 177–185. ht t p s://doi . org/10.1016/0037-0738(92)90082-3