Ab strA ct Planktonic foraminifera were quantitatively analyzed across the Santonian succession and their boundaries at the Jebel Ennahli and Ettout sections, northern Tunisia. The continuous sedimentary succession is dominated by hemi- pelagic facies, allowing a good biostratigraphic correlation for this time interval. Fifty-fife planktonic foraminiferal species belonging to 13 genera have been identified. The distribution pattern of 17 heterohelicids and 38 trochospiral forms reveals the identification of 12 major bio-events and allows establishment of three zones based on heteroheli- cids and five zones based on trochospiral forms. Trochospiral based zones are from the base to the top: 1) Dicarinel­ la primitiva Interval Zone, 2) Dicarinella concavata Interval Zone, 3) Dicarinella asymetrica Total Range Zone, 4) Globotruncanita elevata/Globotruncana arca Concurrent Range Zone, and 5) Globotruncanita ventricosa Interval Zone. The heterohelicid planktonic foraminiferal zones are: 1) Pseudotextularia nuttalli Interval Zone, 2) Sigalia carpatica Interval Zone, and 3) Ventilabrella eggeri/Planoglobuliina manuelensis Concurrent Range Zone. The bio- events and planktonic foraminiferal zones were correlated with previously published works especially on Tunisia and other areas. The lowest occurrence (LO) of Dicarinella asymetrica is the only planktonic foraminiferal datum record- ed across the Coniacian/Santonian boundary (CSB). It occurs slightly below the LO of the inoceramid Platyceramus cycloides cycloides representing a good proxy for the CSB. The Santonian/Campanian boundary in the studied sec- tions is characterized by a major faunal turnover represented by the LO of Ventilabrella and Planoglobulina and the LO of Globotruncana and Globotruncanita slightly above. The boundary interval is also characterized by the high- est occurrence (HO) of Sigalia, Dicarinella, and Whiteinella. Keywords: Santonian, biostratigraphy, planktonic foraminiferal, bioevents, Globotruncanidae, Heterohelicidae, Tunisia. Geologia croatica 67/2 111–126 8 Figs. 1 Pl. Zagreb 2014 Santonian planktonic foraminiferal biostratigraphy of the northern Tunisia  1Zaineb Elamri, 2Sherif Farouk and 3Dalila Zaghbib-Turki 1 University of Kairouan, Institute of Arts and Crafts, Kasserine, 1200, Tunisia 2 Egyptian Petroleum Research Institute, Exploration Department, Nasr City, 11727, Egypt; (geo.sherif@hotmail.com) 3 University of Tunis-El Manar, Faculty of Sciences, Department of Geology, Campus universitaire 2092, Tunisia doi: 10.4154/gc.2014.08 ous papers deal with the planktonic foraminiferal biostratig- raphy of the Upper Cretaceous in Tunisia (e.g. PERVIN- QUIÈRE 1903, 1907; PINI, 1971; DALBIEZ, 1956; SALAJ, 1980; NEDERBRAGT, 1991; RAMI et al., 1997; RO- BASZYNSKI et al.; 2000; ROBASZYNSKI & MZOUGHI 2010; BEY et al., 2012). It is well-known that the Tethyan, or low latitude assemblages are characterized by abundant, highly diverse planktonic foraminiferal assemblages, whereas those from the Circum-Antarctic region are charac- terized by low diversity and usually long-ranging planktonic taxa of simple morphology (PETRIZZO, 2000). Many bio- 1. INtrODUctION Northern Tunisia corresponds to a fold thrust belt linking the North Africa Atlas and the Sicilian Apennine chains, called the peri-Mediterranean orogenic arc (COWARD & RIES, 2003). It was formed during the Cenozoic following the col- lision between the African and European plates. Upper Cre- taceous rocks in Tunisia are characterized by widely distrib- uted, deep marine facies, which are extremely rich in microfauna as well as macrofauna especially ammonites and inoceramids. Therefore a considerable number of previ- Geologia CroaticaGeologia Croatica Geologia croatica 67/2Geologia Croatica 112 stratigraphic studies have been conducted on the Santonian deposits and their boundaries to define the global stratotype section and point (GSSP) but Comparison of the Santonian planktonic foraminiferal bioevents noted in the Tethyan province with other provinces has revealed variations in the stratigraphic ranges (FAROUK & FARIS, 2012). The Olazagutia section (north Spain) was approved as the GSSP for the base of the Santonian by the Subcommis- sion on Cretaceous Stratigraphy, and submitted to the Inter- national Commission of Stratigraphy (ICS) in early 2012. The base of the Coniacian / Santonian boundary is placed at the lowest occurrence of the inoceramid bivalve Cladocera­ mus undulatoplicatus (LAMOLDA et al., 2007; LAMOL DA, 2013). This marker species has not been previously recorded in Tunisia. However, GRADSTEIN et al. (2012) noted that the Olazagutia section is not ideal the biostratigraphic record may be incomplete and the abandoned quarry wall might be unsuitable for future sampling. An alternative candidate is Ten Mile Creek, Dallas County, Texas (GALE et al., 2007), where portions of the record are composed of over lapping sections. Furthermore, the stratotype for the Santonian – Campanian (S/C) boundary is still in the process of ratifica- tion. The S/C transition interval has been studied in many sections in Tunisia (e.g., NEDERBRAGT, 1991, 1993; SALAJ, 1980; ARZ, 1996; ROBASZYNSKI, 1999; RO- BASZYNSKI et al., 2000; JARVIS et al., 2002). The geo- graphic applicability of biostatigraphic zonations is influenced by palaeolatitudinally controlled temperature gradients and the niche preferences of marker species (BRALO WER, 1995). Integration of trochospiral and heterohelicid bio- events in the present study allows a high-resolution biozo- nation, and increased ability to correlate between deep and shallower basins, owing to the different life strategies of the various families (e.g., LI & KELLER, 1998; ARZ & MO- LINA, 2002). The main objectives of the present study are: 1) to define the major planktonic foraminiferal events; 2) to establish a high resolution planktonic foraminiferal biostratigraphic zonation based on the integration of trochospiral and heterohelicid forms; 3) to compare the planktonic foraminiferal bioevents from different palaeolatitudes; 4) to define the Co nia cian- Santonian and Santonian-Campanian stage boundaries. Figure 1: A) Location map of the studied sections. B & C) Geologic map after http://www.erlm.tn/lithotheque/IMG/pdf/carte_geologique_500_000.pdf Elamri et al.: Santonian planktonic foraminiferal biostratigraphy of the northern Tunisia Geologia Croatica 113 2. MAtErIAL AND MEtHODs 151 rock samples were collected from the Kef Formation, sampled approximately every 50 cm from two exposed sec- tions (Fig. 1). The first section named the Ettout section is located on the south eastern flank of the Ellès syncline in central Tunisia (35°56’59“N and 9°6’2“E), while the second section named the Jebel Ennahli section, is located in north- eastern Tunisia in the Ariana area ~5 km from Tunis City towards the north (36° 54’ 46’’ N 10° 09’ 09’’ E). From both sections, the samples are washed following the classic mi- cropalaeontological method. About 200 g of dry rock sam- Figure 2: Stratigraphic correlation of the studied sections in the northern Tunisia, showing the (lowest and highest occurrence) of planktonic marker species. Geologia croatica 67/2Geologia Croatica 114 ta bl e 1: R el at iv e pe rc en t a bu nd an ce s a t E tt ou t s ec tio n se ct io n, c al cu la te d fo r t he > 6 3 µm fr ac tio n on 3 00 -5 00 sp ec im en s. Sa m pl e no . ET 58 ET 61 ET 60 E T6 7 ET 68 ET 69 ET 71 ET 73 ET 75 ET 77 ET 79 ET 82 ET 84 ET 85 ET 88 ET 90 ET 95 ET 97 ET 10 0 ET 10 8 ET 11 5 ET 12 8 ET 13 2 H et er oh el ix g lo bu lo sa 10 7 61 11 2 16 8 15 3 64 77 66 52 26 68 54 11 9 10 7 10 8 19 3 13 8 86 13 3 12 4 66 61 14 8 G lo bi ge rin el lo id es u ltr am ic ru s 31 16 54 30 50 64 87 43 52 17 6 45 69 72 75 12 6 44 56 63 37 45 33 31 88 H et er oh el ix g la br an s 8 7 8 2 35 39 18 4 9 8 19 21 17 21 9 37 20 17 24 10 8 15 21 H et er oh el ix re us si 42 35 74 25 17 13 5 9 10 5 10 9 4 8 8 18 12 13 12 23 11 7 25 H et er oh el ix p ul ch ra 46 90 41 51 36 49 19 2 16 3 87 25 10 4 81 89 66 60 59 91 10 5 61 70 42 22 10 5 Ar ch eo gl ob ig er in a cr et ac ea 6 3 0 1 4 10 2 7 2 0 7 1 0 4 6 7 1 2 5 7 8 13 6 Ar ch eo gl ob ig er in a bl ow i 5 7 8 7 16 37 10 13 14 3 5 2 11 5 28 8 18 5 8 22 8 8 21 G lo bo tr un ca na v en tr ic os a 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 H et er oh el ix ca rin at a 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 G lo bo tr un ca na b ul lo id es 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Co st el la ge rin a pi llu la 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 8 29 H ed be rg el la fl an dr in i 14 31 67 66 44 44 30 10 11 42 7 20 39 59 51 8 10 14 8 18 16 14 39 Co nt us ot ru nc an a fo rn ic at a 2 0 0 18 6 1 0 0 0 2 7 3 2 1 5 6 0 2 5 4 3 3 1 Si ga lia d efl ae ns is 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 6 38 7 10 4 1 4 G lo bo tr un ca na li nn ei an a 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 M ar gi no tr un ca na si nu os a 0 0 0 3 3 1 1 0 1 2 3 6 0 5 3 3 0 1 0 6 4 11 3 H et er oh el ix n av ar ro en sis 2 9 8 5 10 17 13 6 5 6 11 5 3 8 9 8 0 6 2 6 5 0 3 G lo bt ru na ca na a rc a 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 G lo bo tr un ca ni ta ro se tt a 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Si ga lia sp . 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 H et er oh el ix m or em an i 8 7 8 2 9 3 7 6 8 1 4 5 11 8 8 5 3 2 5 10 0 0 4 G lo bo tr un ca ni ta in sig ni s 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 G lo bo tr un ca na m ar ie i 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 G lo bo tr un ca na ca lic ifo rm is 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Ps eu do gl ob ul in a au st in an a 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 2 M ar gi no tr un ca na m ar gi na ta 1 0 3 3 10 6 0 1 1 1 2 1 0 6 9 7 7 14 4 4 4 1 1 D ic ar in el la co nc av at a 0 0 0 0 0 0 0 0 0 0 0 0 0 1 2 1 0 0 0 0 0 0 0 H ed be rg el la S im pl ex 0 0 3 4 22 9 6 0 1 5 0 3 5 8 17 7 2 2 0 10 2 1 6 M ar gi no tr un ca na u nd ul at a 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 2 0 0 0 3 2 3 0 Ve nt ila br el la g la br at a 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 M ar gi no tr un ca na co ro na ta 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 1 0 0 0 1 0 1 1 G lo bo tr un ca ni ta st ua rt ifo rm is 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Ve nt ila br el la e gg er i 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 G lo bo tr un ca na o rie nt al is 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 G lo bo tr un ca ni ta e le va ta 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Ps eu do te xt ul ar ia n ut ta lli 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Co nt us ot ru nc an a pa te lli fo rm is 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 H et er oh el ix st ria ta 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 G lo bo tr un ca ni ta su bs pi no sa 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Ve nt ila br el la a lp in a 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 M ar gi no tr un ca na ps eu do lin ne ia na 1 0 0 0 2 2 2 0 1 8 1 1 1 2 2 4 3 2 3 4 1 2 0 M ar gi no tr un ca na ta rfa ye ns is 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 3 2 1 0 M ar gi no tr un ca na re nz i 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 D ic ar in el la a sy m et ric a 0 0 0 0 0 0 0 0 0 0 1 0 1 1 2 0 1 0 0 3 0 1 0 M ar gi no tr un ca na sc hn ee ga ns i 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Si ga lia ca rp at ic a 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 M ar gi no tr un ca na pa ra co nc av at a 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 6 0 4 1 1 1 0 0 TO TA L 27 4 26 6 38 6 38 6 41 7 35 9 45 0 32 8 25 4 31 3 29 5 28 2 37 5 38 5 45 4 42 5 36 8 37 6 31 5 38 4 22 0 20 4 50 7 Elamri et al.: Santonian planktonic foraminiferal biostratigraphy of the northern Tunisia Geologia Croatica 115 ta bl e 1: c on tin ua tio n Sa m pl e no . ET 13 4 ET 13 9 ET 14 1 ET 14 5 ET 14 6 ET 14 7 ET 14 8 ET 14 9 ET 15 0 ET 15 1 ET 15 2 ET 15 5 ET 15 6 ET 15 7 ET 15 8 ET 15 9 ET 16 0 ET 16 1 ET 16 2 ET 16 3 ET 16 4 ET 16 6 H et er oh el ix g lo bu lo sa 76 13 1 86 35 10 5 17 1 84 70 12 9 27 83 46 24 28 75 50 58 98 88 42 67 56 G lo bi ge rin el lo id es u ltr am ic ru s 38 39 46 36 30 65 47 61 55 64 58 56 67 59 58 52 51 50 52 77 72 56 H et er oh el ix g la br an s 14 17 28 56 65 62 81 30 20 84 51 55 60 54 54 74 51 38 52 55 78 46 H et er oh el ix re us si 12 15 12 16 12 21 31 16 16 14 30 65 45 50 72 36 57 53 48 7 23 18 H et er oh el ix p ul ch ra 40 75 10 5 31 65 78 29 72 10 9 29 37 53 44 42 29 29 16 13 17 7 7 12 Ar ch eo gl ob ig er in a cr et ac ea 7 9 2 0 8 12 23 13 2 3 12 26 18 9 17 14 17 17 10 1 9 10 Ar ch eo gl ob ig er in a bl ow i 6 7 12 0 7 22 17 8 13 3 20 16 16 17 30 52 19 26 35 3 7 7 G lo bo tr un ca na v en tr ic os a 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 7 H et er oh el ix ca rin at a 0 0 0 0 0 0 0 0 0 0 0 5 36 38 19 43 26 24 16 16 13 5 G lo bo tr un ca na b ul lo id es 0 0 0 0 0 0 0 0 0 0 0 7 7 11 8 2 2 5 3 3 4 5 Co st el la ge rin a pi llu la 6 21 13 2 12 10 1 0 2 4 13 16 4 0 7 15 18 16 20 1 0 5 H ed be rg el la fl an dr in i 17 12 27 16 16 30 32 20 33 22 28 38 30 25 29 36 7 21 33 3 6 4 Co nt us ot ru nc an a fo rn ic at a 2 5 2 5 4 7 5 2 1 7 0 5 3 7 2 3 2 1 4 14 3 3 Si ga lia d efl ae ns is 3 4 4 2 16 9 36 22 11 11 9 20 11 15 1 2 6 5 3 5 6 3 G lo bo tr un ca na li nn ei an a 0 0 0 0 0 0 0 0 0 0 0 6 6 7 3 2 3 7 2 16 4 3 M ar gi no tr un ca na si nu os a 3 9 8 17 15 11 6 6 2 9 5 0 2 1 0 3 3 5 10 8 1 3 H et er oh el ix n av ar ro en sis 7 4 5 5 4 21 13 4 4 4 2 9 14 5 9 5 5 4 4 6 3 2 G lo bt ru na ca na a rc a 0 0 0 0 0 0 0 0 0 0 0 9 5 6 6 5 1 2 11 11 2 2 G lo bo tr un ca ni ta ro se tt a 0 0 0 0 0 0 0 0 0 0 0 4 3 1 0 0 1 0 2 17 1 2 Si ga lia sp . 0 0 0 0 0 0 0 0 0 0 0 0 16 2 1 4 0 1 0 1 0 2 H et er oh el ix m or em an i 5 10 1 0 5 4 1 4 2 1 0 8 0 0 1 5 9 10 6 1 0 1 G lo bo tr un ca ni ta in sig ni s 0 0 0 0 0 0 0 0 0 0 0 2 1 0 0 0 0 0 1 1 2 1 G lo bo tr un ca na m ar ie i 0 0 0 0 0 0 0 0 0 0 0 1 0 1 1 1 1 0 1 0 0 1 G lo bo tr un ca na ca lic ifo rm is 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 1 Ps eu do gl ob ul in a au st in an a 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 M ar gi no tr un ca na m ar gi na ta 5 4 1 28 9 11 17 17 5 10 2 1 0 0 0 0 0 1 3 1 4 0 D ic ar in el la co nc av at a 0 2 0 1 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 H ed be rg el la S im pl ex 2 0 3 3 2 3 0 3 1 3 1 0 4 2 0 6 1 2 0 0 0 0 M ar gi no tr un ca na u nd ul at a 4 1 1 2 2 2 1 1 0 1 1 0 0 0 0 0 0 0 0 0 0 0 Ve nt ila br el la g la br at a 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 M ar gi no tr un ca na co ro na ta 1 0 0 2 1 1 0 0 1 1 3 1 0 0 0 0 0 0 0 0 0 0 G lo bo tr un ca ni ta st ua rt ifo rm is 0 0 0 0 0 0 0 0 0 0 0 3 1 1 0 0 0 0 3 0 1 0 Ve nt ila br el la e gg er i 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0 G lo bo tr un ca na o rie nt al is 0 0 0 0 0 0 0 0 0 0 0 7 7 1 0 2 0 5 4 4 2 0 G lo bo tr un ca ni ta e le va ta 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 1 1 2 4 0 0 Ps eu do te xt ul ar ia n ut ta lli 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 1 1 2 5 0 0 0 Co nt us ot ru nc an a pa te lli fo rm is 0 0 0 0 0 0 0 0 0 0 0 0 2 1 0 0 0 0 1 0 0 0 H et er oh el ix st ria ta 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 G lo bo tr un ca ni ta su bs pi no sa 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 2 0 1 1 0 0 Ve nt ila br el la a lp in a 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 M ar gi no tr un ca na ps eu do lin ne ia na 6 8 8 19 6 3 1 6 3 5 12 0 0 0 0 0 0 0 0 0 0 0 M ar gi no tr un ca na ta rfa ye ns is 2 0 0 2 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 M ar gi no tr un ca na re nz i 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 D ic ar in el la a sy m et ric a 5 4 2 0 6 3 0 2 3 0 0 0 0 0 0 0 0 0 0 0 0 0 M ar gi no tr un ca na sc hn ee ga ns i 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Si ga lia ca rp at ic a 0 0 0 0 0 0 0 0 0 0 5 0 0 0 0 0 0 0 0 0 0 0 M ar gi no tr un ca na pa ra co nc av at a 1 0 0 3 1 0 0 3 0 1 0 0 0 0 0 0 0 0 0 0 0 0 TO TA L 26 2 37 7 36 6 28 1 39 1 54 6 42 5 36 1 41 2 30 3 37 3 46 5 42 6 38 3 42 2 44 9 35 8 40 8 43 7 30 7 31 5 25 5 Geologia croatica 67/2Geologia Croatica 116 ples were disaggregated were soaked in dilute hydrogen per- oxide (H2O2), washed through a 63 µm sieve, and then dried. Population counts are based on random splits of 300-500 specimens in the size fraction larger than 63 µm. All spe- cimens were picked, identified and mounted on micro slides for permanent record. Results of the quantitative analyses for the Santonian succession and their boundaries at the Et- tout section and the Santonian/ Campanian boundary at Jebel Ennahli section are listed in Tables 1 and 2 respecti vely. The most important foraminiferal specimens were digitally im- aged under the Phillips XL30 Scanning Electron Microscope (SEM) in the laboratories of the Egyptian Mineral Resources Authority (E.M.R.A.), having been sputtering coated for 8 min with gold at 20–30 mA°. In addition, several thin sec- tions were prepared of indurated carbonate samples to assist in microfacies analysis and foraminiferal species determina- tion. 3. LItHOstrAtIGrAPHY The present study deals mainly with the Kef Formation (FOURNIÉ, 1978) which overlies the Bahloul Formation and underlies the Abiod Formation. The age of the Kef For- mation is Late Turonian to Early Campanian (ROBASZYN- SKI et al.; 2000; ROBASZYNSKI & MZOUGHI 2010). It consists mainly of marl and limestone deposited in a pelagic or hemi-pelagic ramp setting. It is rich in inoceramids, e.g., Endocostea ghadamensis (TROGER & RÖHLICH) and in foraminifera, including Globotruncana and Globo­ truncanita representatives of Campanian age (BUROLLET, 1956; SALAJ, 1980; BELLIER, 1983; RAMI et al., 1997; ROBASZYNSKI et al., 2000). At the Ettout section, the lower part of the Kef Forma- tion (FOURNIÉ, 1978) is composed of marl with fossilifer- ous limestone and small pelecypods (Nucula sp.). The fre- quency of these limestone interbeds increases towards the middle part (SALAJ, 1980; BELLIER, 1983; MATMATI et al., 1991; RAMI et al., 1997; ELAMRI & ZAGHBIB-TUR- KI, 2005). The middle portion of the Kef Formation con- tains the inoceramid bivalve Platyceramus cycloides (WEG- NER) and ammonite Texanites texanus texanus (ROMER). Towards, the upper parts of the Kef Formation, limestone beds are less frequent with very scarce macrofossils represented only by the echinoid species Pleisaster peini (COQUAND) in the Ettout section, followed by the predominantly white limestones of the Abiod Formation (BU ROLLET, 1956). A similar succession is observed at the Jebel Ennahli section with an observed lack of megafossils in the whole measured section, suggesting that these variations in macrofaunal as- semblages may be environmentally controlled (Fig. 2). 4. bIOstrAtIGrAPHY The biostratigraphy of the Upper Coniacian – Lower Cam- panian succession in the study area is constructed with some modification based on the Heterohelicidae planktonic fora- miniferal zonal scheme of NEDERBRAGT (1990) and the scheme of ROBASZYNSKI et al., (2000) for trochospiral forms. Four Tethyan trochospiral forms and three Heterohe­ licidae planktonic foraminiferal zones are identified in this study, based on the lowest and highest occurrence, (LOs, HOs) of the marker species. The biostratigraphic ranges of the identified planktonic foraminiferal species are given in Figs. 3 and 4. The most important planktonic foraminiferal taxa are illustrated in Plate 1. The established planktonic fo- table 2: Relative percent abundances around the Santonian / Campanian at Jebel Ennahli section, calculated for the > 63 µm fraction on 300-500 spe- cimens. Constusotruncana fornicata 20 12 50 5 31 12 60 75 30 Marginotruncana undulata 5 11 0 3 5 0 0 0 0 Marginotruncana sigali 1 0 4 1 0 0 0 0 0 Heterohelix navarroensis 1 23 30 12 20 30 15 0 0 Ventilabrella decoratissima 0 2 30 14 10 0 0 12 0 Marginotruncana schneegansi 0 1 0 0 0 0 0 0 0 Ventilabrella eggeri 0 1 1 14 50 6 0 0 0 Globotruncana arca 0 0 0 0 15 2 0 0 1 Globotruncana linneiana 0 0 0 0 7 18 15 0 25 Globotruncana orientalis 0 0 0 0 6 24 14 6 14 Planoglobulina manuelenisis 0 0 0 0 10 0 0 0 0 Ventilabrella glabrata 0 0 0 0 0 12 0 0 0 Heterohelix carinata 0 0 0 0 0 36 6 0 62 Globotruncanita elevata 0 0 0 0 5 12 27 45 20 Pseudotextularia nuttalli 0 0 0 0 0 2 35 4 35 Globotruncana bulloides 0 0 0 0 0 0 6 5 16 Globotruncana mariei 0 0 0 0 0 0 0 20 30 Total 379 353 600 348 535 345 386 413 541 Elamri et al.: Santonian planktonic foraminiferal biostratigraphy of the northern Tunisia Geologia Croatica 117 Figure 3: Lithology of the Coniacian – Campanian at Jebel Ettout section, with sample positions, range of planktonic foraminifera, and biostratigraphic zone; for symbol key see Fig. 2. raminiferal bioevents and biozones arranged from older to younger are described below. 4.1. Globotruncanidae biozones 4.1.1. Dicarinella primitiva Zone Definition: this zone covers the interval from the LO of Dicarinella primitiva to the LO of Dicarinella concavata. Author: CARON (1978). Age: Late Turonian-Early Coniacian. The present study deals only with the upper part of this zone. Assemblage: The Globotruncanidae are predomi nan t- ly recorded in this zone represented by Dicarinella imbri­ ca ta, Marginotruncana paraconcavata, M. schneegansi, M. sigali, M. renzi, M. coronata, M. undulata, M. pseudo lin neia­ na in addition to the less common occurrence of Witheinella paradubia, Witheinella brittonensis and Preaglobo trun cana gibba. For the complete assemblage see Figs. 3 & 4. Geologia croatica 67/2Geologia Croatica 118 Figure 4: Lithology of the Coniacian – Campanian at Jebel Ennahli section, with sample positions, range of planktonic foraminifera, and biostratigra phic zone; for symbol key see Fig. 2. Dicarinella spp. The zone is similar to that of the underly- ing Dicarinella primitiva zone with the extinction of Mar­ ginotruncana marianosi (Figs. 3 and 4). Remarks: The LO of Dicarinella concavata is dated as Late Turonian (PREMOLI SILVA & VERGA, 2004; ARD- ESTANI et al., 2011), while other authors attributed it to the Late Coniacian (SIGAL, 1955; BELLIER, 1983; ROBA S ZYN- SKI et al., 1984; CARON, 1985; RAMI et al., 1997; RO- BASZYNSKI, 1998; ROBASZYNSKI & CARON, 1995; PREMOLI SILVA & SLITER, 1999; ÖZKAN-ALTINER & ÖZCAN, 1999; ROBASZYNSKI et al., 2000; SA RI, 2009; FAROUK AND FARIS, 2012; Figs 3 & 4). The present Di­ carinella concavata Zone is approximately equivalent to the upper part of the Dicarinella concavata Zone of GRADSTEIN et al. (2012) and HAQ (2014), and coincides with the Late Co- niacian CC14 nannofossil Zone (FAROUK & FARIS, 2012). 4.1.3 Dicarinella asymetrica Zone Definition: Total range zone of the nominated taxon. Age: Santonian Remarks: The stratigraphic range of Dicarinella prim­ itiva differs from the two studied sections. The HO of Di­ carinella primitiva at the Ettout section is placed at the C/S boundary directly below the LO of Dicarinella asymet­ rica. At Jebel Ennahli it is placed below the LO of Di­ carinella concavata within the Dicarinella primitiva Zone (Figs. 3 & 4). This zone is attributed by different authors to the Early Coniacian (e.g., WONDERS, 1980; Caron, 1985; RAMI, 1998; ABDEL-KIREEM et al., 1995; ELAMRI & ZAGHBIB-TURKI, 2005), while it is dated as Late Turonian by other authors (PREMOLI-SILVA & SLITER, 1999). This biozone is considered to be of Late Turonian-Early Conia- cian age in the Tunisian sections (NEDERBRAGHT, 1991). 4.1.2. Dicarinella concavata Zone Definition: This zone covers the interval from the LO of Dicarinella concavata to the LO of Dicarinella asymetrica.. Author: SIGAL (1955). Age: Late Coniacian Assemblage: In this interval the assemblages are highly abundant and contain well preserved Marginotruncana and Elamri et al.: Santonian planktonic foraminiferal biostratigraphy of the northern Tunisia Geologia Croatica 119 Author: POSTUMA (1971) Assemblage: This biozone in both sections is character- ized by the coexistence of predominant planktonic foraminif- eral species belonging to the Dicarinella and Marginotrun­ cana genera. The marginotruncanids diminish in abundance and size toward the top of the Dicarinella asymetrica Zone. In this Zone, the LO of the genus Sigalia was observed in addition to Ventilbrella decoratissima, Costellagerina pil­ Figure 5: Comparison of different marker species distribution across the Santonian / Campanian boundary in Tunisia. Figure 6: Bioevents observed from the Coniacian to Campanian and proposed planktonic foraminiferal zones. Geologia croatica 67/2Geologia Croatica 120 ula, Contusotruncana patelliformis and Globotruncana man­ aurensis; for the complete assemblage see Figs. 3 and 4. Remarks: The LO of Dicarinella asymetrica is more reliable for indicating the C/S boundary (e.g., MELINTE & LAMOLDA, 2002; GRADSTEIN et al., 2012). In Tunisian sections, according to ROBASZYNSKI et al., (2000), the LO of Dicarinella asymetrica indicates the lowest Santonian and occurs within the calcareous nannofossil CC15 Zone and is placed slightly below the LO of Platyceramus cycloides (Figs 3 and 4). At the Ettout section, the LO of Dicarinella asymetrica is observed at ~7m below the LO of Platycera­ mus cycloides. 4.1.4. Globotruncanita elevata/Globotruncana arca Zone Definition: Partial range zone from the HO of D. asy­ metrica to the LO of Globotruncana ventricosa. Author: modified after DALBIEZ (1955). Age: Early-Middle Campanian Assemblage: Planktonic foraminiferal abundance is ge- ne rally high and preservation is usually good. Common species include Hedbergella flandrini, Globigerinelloides ultra­ micrus, Archaeoglobigerina blowi, A. creta cea, Contuso­ truncana fornicata especially in the Ennahli section. Rare species include Hedbergella simplex, Globotruncana lin nei­ ana, Costellagerina pilula, Marginotruncana sinusoa and M. un dulata are also recorded (Figs 6 & 7). Remarks: The base of the Campanian is placed before the HO of Dicarinella asymetrica (considered to be a reli- able bioevent to define the base of the Campanian), (PE- TRIZ ZO, 2000; WAGREICH et al. 2010). It is easily recog- nizable and widely distributed in different palaeolatitudes. In the Tunisian sections, the HO of D. asymetrica occurs at the Santonian/ Campanian boundary (e.g., RAMI, 1998; RO- BASZYNSKI et al. 2000; Fig. 5). At the Santonian-Campa- nian transition, many events are observed 1) the extinction of Sigalia, Dicarinella and Whiteinella; 2) the marginotrun- canids suffered a gradual extinction; 3) an increase in the Figure 7: Relative abundance of the planktonic foraminiferal species correlates to the lithology and biozones at Jebel Ettout section; for symbol key see Fig. 2. Elamri et al.: Santonian planktonic foraminiferal biostratigraphy of the northern Tunisia Geologia Croatica 121 relative abundance of flat biserial and multiserial Heterohe- licids (Ventilabrella and Planoglobulina); 4) an increase in the relative abundance of Globotruncana and Globotruncanita genera (Figs. 7 & 8). The LO of Globotruncanita elevate and G. arca occurs slightly before the HO of D. asyme tri­ ca marker of the base of the Campanian stage (ROBAZSYN- SKI et al., 2000; Figs 5 and 6). According to WAGREICH et al. (2010), the base of the Campanian is placed after the FO of Globotruncanita elevata as recorded in Tunisian sec- tions. The upper part of the Globotruncanita elevata Zone is defined by the LO of Globotruncana ventricosa. Actually, this event is problematic as it shows considerable variation in the stratigraphic ranges between different latitudes (PE T- RIZZO, 2000; FAROUK & FARIS, 2012). On the north- western Australian margin, Globotruncana ventricosa ranges down into at least the Santonian Dicarinella asymetri ca Zone, and cannot be used to mark the upper boundary of the G. el­ evata Zone. The LO of G. ventricosa occurs in the middle Campanian in Tethyan zonations and also in the present stu dy (e.g., CARON, 1985; ROBASZYNSKI & CARON, 1995; ROBASZYNSKI et al., 2000; MANCINI & PUC- KETT, 2005; FAROUK & FARIS, 2012). 4.2. Heterohelicid biozones 4.2.1. Pseudotextularia nuttalli Zone Definition: Interval from the LO of Pseudotextularia nuttalli to the LO of Sigalia carpatica. Age: Coniacian – Early Santonian. Author: NEDERBRAGHT (1990) Assemblage: This interval is marked by a high diversity and abundance of heterohelicid foraminifera with good preser- vation (e.g., Heterohelix reussi, H. globulosa, H. glabrans, H. sphenoides, H. moremani, H. pulchra and H. navarroensis). Remarks: The LO of Pseudotextularia nuttalli is placed within the lowermost Coniacian by a sporadic occurrence (e.g., NEDERBRAGT, 1990; RAMI, 1998; LAMOLDA et al., 2007). According to NEDERBRAGT (1990), the Pseu­ dotextularia nuttalli Zone is attributed to the chronostrati- graphic interval from the Coniacian to the Santonian. In the present study, it is attributed to the Coniacian – Early San- tonian (Fig. 6). 4.2.2. Sigalia carpatica Zone Definition: Interval from the LO of Sigalia carpatica to the LO of Ventilabrella eggeri. Age: Late Santonian Author: SALAJ & SAMUEL (1966) Assemblage: This interval is marked by an abundance of Heterohelicids with good preservation (e.g. Heterohelix reussi, H. globulosa, H. glabrans, H. sphenoides, H. more­ mani, H. pulchra, H. navarroensis, Sigalia deflaensis, and Ventilabrella decoratissima). Rare large biserial and flat mul- tiserial heterohelicid morphogroup including Pseudotextu­ laria, Planoglobulina, Sigalia and Ventilabrella are observed in the middle and upper parts of the Santonian deposits. They do not exceed 10% at the Ettout section, increase to around 16% of the total assemblages at the Ennahli section. Remarks: In the Tunisian sections, there is an absence of flat heterohelicid species, with limbate sutures such as Si­ galia deflaensis, S. carpatica. Large multiserial heteroheli- cids Ventilabrella decoratissima are observed near the base of the Santonian which is also different (e.g., NEDER- BRAGT, 1991; RAMI et al., 1997; EL AMRI & ZAGHBIB- TURKI, 2005 and the present study). ROBASZYNSKI & CARON (1995) mentioned that Sigalia carpatica appears before the LO of Sigalia deflaensis. In the present study, the Figure 8: Relative abundance of the planktonic foraminiferal across the Santonian - Campanian boundary correlates to the lithology and biozones at the Ennahli section. Geologia croatica 67/2Geologia Croatica 122 LO of Sigalia deflaensis appears earlier than Sigalia carpat­ ica at the Ettout section while at the Jebel Ennahli section it appears together with Sigalia carpatica and Ventilabrella decoratissima. The LO of flat heterohelicids with limbate sutures such as Sigalia carpatica and Ventilabrella decora­ tissima is recorded above the LO of Dicarinella asymetrica. The LO of Sigalia carpatica is used as a second marker for the Coniacian/Santonian boundary in the proposed GSSP at the Olazagutia section (LAMOLDA, 2013). This event is problematic as it shows considerable variation in age due to it’s rarity and sporadic presence in Tunisian sections (RAMI et al., 1997), although it is easily recognized by its flat het- erohelicids with limbate sutures. Many authors suggested the LO of Dicarinella asymetrica and Sigalia carpatica co- occur together (Salaj, 1980; ROBASZYNSKI AND CARON, 1995). Other authors noticed that the LO of Sigalia carpat­ ica does not occur simultaneously with the LO of Dicarinella asymetri ca (e.g., NEDERBRAGT, 1991; RAMI et al., 1997; Robaszynski et al., 2000; EL AMRI & ZAGHBIB-TURKI, 2005). In the pre sent study, the LO of this taxon occurs higher in the Upper Santonian succession and does not co- incide with the LO of Dicarinella asymetrica (Fig. 6). At the Jebel Ennahli section, the LO of Sigalia deflaensis occurs simultaneously with the LO of Sigalia carpatica and Venti­ labrella decoratissima, while in the Ettout section, the LO of Sigalia carpatica appears higher, after the LO of Sigalia deflaensis. 4.2.3. Ventilabrella eggeri/Planoglobulina manuelenisis concurrent range Zone Definition: Interval from the HO of Sigalia carpatica to the LO of Gublerina acuta Age: early Campanian Author: modified after Nederbragt (1991) Assemblage: Ventilabrella aplina, V. eggeri, V. glabra ta, Planoglobulina manuelensis, and Heterohelix carinata are common in this zone, for the complete assemblage see Figs. 3 & 4. Remarks: The LO of Ventilabrella eggeri was used as a good marker for the Santonian and Campanian boundary (NEDERBRAGT, 1991; ROBASZYNSKI & CARON, 1995). It is associated with the HO of Sigalia spp. and Di­ carinella spp, which marks the base of the Campanian. The LO of Planoglobulina manuelensis appears together with Ventilabrella eggeri simultaneously at the base of the Globotruncanita elevata Zone (Figs. 3 and 4). However, Arz (1996) adopts the LO of Ventilabrella eggeri to mark the ter- minal Santonian as recorded at the Jebel Ettout section, while at the Ennahli section, it is recorded near the base of the Cam- panian (Figs. 3 & 4). NEDERBRAGT (1991) gave a Late Santonian – Early Campanian age for the V. eggeri Zone. In the present study, this zone is approximately equivalent to the lower part of the Globotruncanita elevata / Globotrun­ cana arca Zone. In both studied sections, only the lower part of the Ventilabrella eggeri/Planoglobulina manuelenisis Zo- ne was investigated. 5. PLANKtONIc FOrAMINIFErAL rELAtIVE AbUNDANcEs The distribution of planktonic foraminifers depends on sea surface water temperature and density. Diverse geometric tests were used to separate and distinguish the specimens found in particular depth ranges within the water column (ARDESTANI et al., 2013). Three groups of planktonic for- aminifera were identified on the basis of different depth zones (PETRIZZO, 2002; ARDESTANI et al., 2013): shal- low surface water forms (SWF), intermediate water foramin- ifera (IWF) and deep water forms (DWF) as follows: Surface water foraminifera: (SWF): This group is rep- resented by simple morphotypes (Heterohelix globulosa, H. moremani, and H. reussi) or the non-keeled trochospiral mor- photype group (Whiteinella paradubia and W. brittonensis). Intermediate water foraminifera (IWF): This group is represented by Preaglobotruncana gibba, Heterohelix pul­ chra, H. glabrans, H. carinata, Hedbergella delrieonsis, Hd. simplex, Globigerinelloides ultramicrus, Archaeoglobige­ rina blowi and Ar. cretacea. Deep water foraminifera (DWF): This group consists of ornamented and trochospiral forms of planktonic fora- Plate: 1-3 Dicarinella asymetrica; sample ET82. 4-6 Dicarinella concavata; sample ET69. 7 Hedbergella simplex; sample EN64. 8 Whiteinella paradubia; sample ET160. 9-10 Marginotruncana tarfayaensis; sample EN59. 11-12 Marginotruncana pseudolinneiana; sample EN64. 13-15 Marginotruncana sinuosa, sample EN64. 16-18 Globotruncanita elevata; sample ET160. 19-20 Contusotruncana fornicata; sample ET81. 21 Heterohelix pulchra; sample EN66. 22-23 Heterohelix striata; sample EN65. 24-25 Pseudotextularia nuttalli; sample EN56. 26 Sigalia carpatica; sample ET154. 27 Planoglobulina manuelensis; sample EN66. 28 Ventilabrella eggeri; sample EN66. (EN=Ennahli section; ET= Jebel Ettout section) Scale bar: 100µm Elamri et al.: Santonian planktonic foraminiferal biostratigraphy of the northern Tunisia Geologia Croatica 123 Geologia croatica 67/2Geologia Croatica 124 minifera including Pseudotextularia nuttalli, Marginotrun­ cana renzi, M. schneegansi, M. undulata, M. paraconcavata, M. coronata, M. tarfayaensis, M. sinusoa, M. marginata, M. pseudolinneiana, Contusotruncana fornicata, C. patelli­ formis, Globotruncanita elevata, Gt. insignis, Globotrun­ cana arca, G. orientalis, G. mariei, G. bulloides, Sigalia car­ patica, Ventilabrella decoratissima, V. eggeri, V. glabrata, V. alpina, Planoglobulina manuelensis. Dicarinella conca­ vata, D. primitiva and D. asymetrica. The planktonic foraminiferal assemblages are dominated by the small heterohelicid representatives mainly H. globu­ losa during the Coniacian of the Dicarinella primitiva Zone (Fig. 7). Other species of the Heterohelicidae group are less abundant and represented by Heterohelix navarroensis and H. moremani. Thus, at the Ettout section, the relative abundance of this species reaches 60 % of the total assemblage (Fig. 7). The Heterohelix spp. are associated with other cosmopolitan species belonging to Hedbergella, Globigerinelloides and Ar­ chaeoglobigerina genera that were considered as subsurface water dwellers. Their relative abundance does not exceed 30%. At the Coniacian / Santonian boundary, a decrease in the abundance of the simple morphotype Heterohelix globu­ losa from 60 % to 20 % is followed by an increase in the abundance of keeled trochospiral morphogroup belonging to the genus Marginotruncana. The latter is considered as the most abundant and the most diversified group (Fig. 7). This turnover is related to an increase in water depth during the Santonian. The relative abundance of the total planktonic foraminifera in the two studied sections reaches 20 % of the total assemblage (>100 µm size fraction). The dominance of the Santonian assemblages by heterohelicids and unkeeled morphotypes such as representatives of Globigerinelloi des, Hedbergella and Archaeoglobigerina and the presence of keeled trochospiral morphotypes belonging to Dicari nel la, Marginotruncana, Globotruncanita and Globotruncana gen- era, does not exceed 20 % of the planktonic foraminiferal assemblage. A major turnover in planktonic foraminifera occurred across the Santonian/Campanian (S/C) boundary associated with 1) the sharp extinction of Dicarinella and Sigalia; 2) the gradual extinction of Marginotruncana; and 3) an increase in the relative abundance of Globotruncanita and Globotrun- cana genera. This turnover could be related to an improve- ment in their ability for better adaptation to a deeper habitat of the photic water column (Figs. 7 & 8). 6. cONcLUsION – Fifty-fife planktonic foraminiferal taxa belonging to 17 he terohelicid and 38 trochospiral forms are identified with mo derate to good preservation and relatively high diversity. – These microfossil assemblages allowed subdivision of the studied sections based on two different zonation schemes (Heterohelicidae and Globotruncanidae) to produce a higher resolution biostratigraphy and better correlation between deep and shallower basins. – The base of the Santonian is marked by the LO of Di­ carinella asymetrica associated with a decrease of the sim- ple morphotypes and increase of keeled trochospiral mor- phogroup indicating a deepening phase. – A major turnover in planktonic foraminifera occurred at the Santonian-Campanian transition. 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Manuscript received December 02, 2013 Revised manuscript accepted May 28, 2014 Available online June 17, 2014 APPENDIX List of species identified in this work, arranged alphabeti- cally by genus with author attributions and dates. 1. Archaeoglobigerina blowi PESSAGNO, 1967 2. Archaeoglobigerina cretacea D’ORBIGNY, 1840 3. Contusotruncana fornicata (PLUMMER, 1931). 4. Contusotruncana patelliformis (GANDOLFI,1955) 5. Costellagerina pilula BELFORD, 1960 6. Dicarinella asymetrica (SIGAL, 1952) 7. Dicarinella concavata (BROTZEN, 1934) 8. Dicarinella imbricata (MORNOD, 1949) 9. Dicarinella primitiva (DALBIEZ, 1955) 10. Globotruncana arca (CUSHMAN, 1926) 11. Globotruncana mariei BANNER & BLOW, 1960 12. Globotruncana bulloides (VOGLER, 1941) 13. Globotruncana caliciformis DE LAPPARENT, 1918 14. Globotruncana linneiana (D’ORBIGNY, 1839) 15. Globotruncana manaurensis GANDOLFI, 1955 16. Globotruncana orientalis EL NAGGAR, 1966 17. Globotruncana rosetta (CARSEY, 1926) 18. Globotruncana ventricosa WHITE, 1928 19. Globotruncanita elevata (BROTZEN, 1934) 20. Globotruncanita insignis (GANDOLFI, 1955) 21. Globotruncanita stuartiformis (DALBIEZ, 1955) 22. Globigerinelloides ultramicra (SUBBOTINA, 1949) 23. Hedbergella delrioensis (CARSEY, 1926) 24. Hedbergella flandrini PORTHAULT, 1970 25. Hedbergella simplex (MORROW, 1934) 26. Heterohelix glabrans (CUSHMAN, 1938) 27. Heterohelix globulosa (EHERENBEG, 1840) 28. Heterohelix moremani (CUSHMAN, 1938) 29. Heterohelix navarroensis LOEBLICH, 1951 30. Heterohelix pulchra (BROTZEN, 1936) 31. Heterohelix reussi (CUSHMAN, 1938) 32. Heterohelix sphenoides MASTERS, 1976 33. Heterohelix carinata (CUSHMAN, 1938) 34. Marginotruncana coronata (BOLLI, 1945) 35. Marginotruncana marginata (REUSS, 1845) 36. Marginotruncana marianosi (DOUGLAS, 1969) 37. Marginotruncana paraconcavata PORTHAULT, 1970 38. Marginotruncana pseudolinneiana PESSAGNO, 1967 39. Marginotruncana schneegansi (SIGAL, 1952) 40. Marginotruncana sigali (REICHEL, 1949) 41. Marginotruncana sinuosa PORTHAULT, 1970 42. Marginotruncana tarfayaensis (LEHMANN, 1962) 43. Marginotruncana undulata (LEHMANN, 1963) 44. Praeglobotruncana gibba KLAUS, 1960 45. Planoglobulina manuelensis (MARTIN, 1972) 46. Pseudoplanoglobulina austinana LOEBLICH & TAP- PAN, 1987 47. Pseudotextularia nuttalli (VOORWIJK, 1937) 48. Sigalia carpatica SALAJ & SAMUEL, 1963 49. Sigalia deflaensis (SIGAL, 1952) 50. Ventilabrella alpina DE KLASZ, 1953 51. Ventilabrella decoratissima (DE KLASZ, 1953) 52. Ventilabrella eggeri CUSHMAN, 1928 53. Ventilabrella glabrata CUSHMAN, 1938 54. Whiteinella brittonensis (LOEBLICH & TAPPAN, 1961) 55. Whiteinella paradubia (SIGAL, 1952)