taxonID	type	description	language	source
03FD879FFFC5FFF0FFA8B6EBC2E8F870.taxon	materials_examined	Type species: Cladodus occidentalis Leidy, 1859; upper Coal Measures of Manhattan, Kansas, Pennsylvanian. Etymology: In honour of the late Russian palaeontologist, Dr. Leonid Glikman, who thoroughly studied this genus and was the first to propose its ctenacanthiform affinity; the suffix − us indicates the masculine gen− der of the name. Referred species. — Glikmanius occidentalis (Leidy, 1859), G. myachkovensis (Lebedev, 2001). Diagnosis. — Sharks with cladodont teeth having a robust, triangular median cusp, strongly convex lingually and slightly convex or flattened labially, with a well developed depression in the basolabial part. There are usually from two to four pairs of lateral cusps, the outermost the largest. At least one pair of intermediate cusplets is not in line with the others, but positioned labially. The base is reniform, with two rounded, compact basolabial projections flanking the labial depression, and two widely spaced buttons on the oral−lingual side. Differential diagnosis. — Teeth of Glikmanius gen. nov. present a unique combination of features, most of them observed in other cladodont shark taxa. They share the shape of the tooth−crown with Cladodus Agassiz, 1843, and particularly with Cladodus bellifer St. John and Worthen, 1875, but differ clearly from the latter by a greater depth of the basolabial depression and the presence of two pairs of separate basal articulation devices (buttons and basolabial projections). Similar basal features are observed in the teeth of Heslerodus Ginter, 2002 (= Phoebodus heslerorum sensu Williams 1985) which, however, are characterised by a phoebodont−like crown with delicate, slender cusps. Prominent, labially flattened median cusp, typical of Glikmanius, occurs in Ctenacanthus Agassiz, 1838 (see Dean 1909) and Symmorium Cope, 1893, but in the latter two genera, as in the case of Cladodus, the articulation devices are in a form of an undivided orolingual ridge and a single basolabial shelf. Remarks on tooth histology. — The observations on the internal morphology of Glikmanius teeth made by Mertiniene (1995) and a new study in transmitted light of a tooth immersed in aniseed oil (Fig. 1 F – H) showed that the whole crown is covered by a thin, uniform layer of enameloid and pallial dentine (Fig. 1 G, H). The internal part of the median cusp (Mertiniene 1995: fig. 2) and larger lateral cusps (Fig. 1 H) is composed of osteodentine. The basal vascular system consists of a network of numerous, thin, and sinuous canals which occupy the whole interior of the base (Fig. 1 F). Between the buttons, usually about 2 – 4 larger labio−lingual canals occur. Stratigraphic range. — Carboniferous, Serpukhovian – Perm− ian, Wordian (= Kazanian).	en	Ginter, Michał, Ivanov, Alexander, Lebedev, Oleg (2005): The revision of “ Cladodus ” occidentalis, a late Palaeozoic ctenacanthiform shark. Acta Palaeontologica Polonica 50 (3): 623-631, DOI: 10.5281/zenodo.13620880
03FD879FFFC5FFF5FCE2B7ADC186FA35.taxon	description	Figs. 1 A, C – E, 2 A, B.	en	Ginter, Michał, Ivanov, Alexander, Lebedev, Oleg (2005): The revision of “ Cladodus ” occidentalis, a late Palaeozoic ctenacanthiform shark. Acta Palaeontologica Polonica 50 (3): 623-631, DOI: 10.5281/zenodo.13620880
03FD879FFFC5FFF5FCE2B7ADC186FA35.taxon	description	pl. 6: a, b, pl. 13: a – d. Cladodus occidentalis; Leidy 1873: 311 – 312, pl. 17: 4 – 6. Cladodus lamnoides Newberry and Worthen, 1866; Trautschold 1874: 286 – 288, text−fig.; cf. pl. 28: 3 c – e; non pl. 18: 3 a, b. Cladodus occidentalis; Woodward 1889: 24. Cladodus mortifer Newberry and Worthen, 1866; Newberry 1897: 285, pl. 22: 2. Cladodus girtyi sp. nov.; Hay 1900: 98 – 100, fig. 2. Cladodus girtyi Hay; Hay 1902: 268. Cladodus mortifer Newberry and Worthen, 1866; Hay 1902: 269. Cladodus occidentalis Leidy; Hay 1902: 269. Cladodus occidentalis Leidy; Eastman 1903: 168, pl. 2: 3, 8, 9. Cladodus sp.; Stukenberg 1905: 110, pl. 13: 24. Cladodus sp.; Pavlov 1914: 19, fig. 7. Cladodus occidentalis Leidy; Branson 1916: 652 – 653, pl. 2: 23, 24. Ctenacanthus occidentalis; Glikman 1964 a: pl. 1: 5. Ctenacanthus occidentalis (Leidy); Glikman 1964 b: pl. 3: 10 – 12. Cladodus occidentalis Leidy; Zidek 1973: fig. 2. Cladodus sp.; Case 1973: figs. 13 – 18. Symmorium reniforme Cope; Williams 1985: 107, pl. 7: 2 – 13. Symmorium reniforme; Mapes and Hansen 1984: fig. 2. cf. Symmorium sp. indet.; Goto et al. 1988: 292, fig. 2, pl. 1: 1. Symmorium reniforme; Hansen and Mapes 1990: fig. 171. Symmorium reniforme Cope; Zidek 1992: 152 – 153, fig. 7. cf. Symmorium reniforme Cope; Mertiniene 1995: 148, figs. 1, 2. Symmorium reniforme Cope; Hansen 1996: 291, fig. 21 − 5.1. Symmorium occidentalis [sic] (Leidy); Lebedev 1996: 394, fig. 7 A, B. Ctenacanthus volgensis A. Minikh, sp. nov.; Minikh and Minikh 1996: 262, pl. 5.4 − I: 1 a, b.? Symmorium lamnoides Newberry and Worthen, 1866; Lebedev 2001: pl. 41: 3. cf. Ctenacanthus artiensis Kozlov, sp. nov.; Kozlov 2000: 152 – 153, pl. 3: 4 [non fig. 5]. Symmorium reniforme Cope; Lucas and Estep 2000: 22 – 23, fig. 6 A – O. “ Symmorium ” occidentalis (Leidy); Malysheva et al. 2000: fig. 2 A – C. “ Cladodus ” occidentalis Leidy; Ginter 2002: fig. 1 D – F. “ Cladodus ” occidentalis; Elliott et al. 2004: 275 – 276, fig. 4 J – M. Original diagnosis (from Leidy 1859: 3). — “ Enameled crown, when perfect, about an inch in length, demi−conical; the outer convex side provided with narrow oblique folds. Lateral denticles two, the outer one the larger. Base of the tooth reniform, with a breadth of about an inch, and the short diameter about 5 lines; lateral extremities provided with a pair of large ovoid tubercles, one above the inner margin, the other below the outer margin. ” Description of the holotype, specimen ANSP 8394, from the upper Coal Measures of Manhattan, Kansas, by Leidy (1873: 311; see Fig. 1 A). — “ The specimen has lost one−half of its base, a large portion of its principal cusp, and the points of the lateral cusps, but sufficient remains to give us a correct idea of the form of the perfect tooth. The base of the tooth is oblong in outline, with the inner [= lingual] border somewhat angular and the outer [= labial] one concave. Its upper inner surface slopes from the cusps, and near its margin, a short distance from the extremities, supports a pair of oval tubercles. Similar protuberances occupy a position beneath the base externally. The median or principal cusp of the tooth is elongated demiconical, with acute lateral edges. The inner convex surface of the cusp at its base exhibits sharp, oblique folds or striae. The outer less convex or nearly flat surface is smooth, except a few vertical wrinkles at its base. The lateral denticles on each side of the principal cusp are two, of which the outer is the larger. In its perfect condition the tooth has approximated 1 1 / 4 inches in length and about 1 inch in breadth at base. ” Description based on additional material. — As evident from the literature and museum collections, numerous teeth of G. occidentalis were studied in Russia, USA, and England before and after the descriptions by Leidy (1859, 1873). Still more are yet unpublished. Based on all the material that was available to us, and especially, the specimens from the Moscovian of central Russia, from the Kazanian of the Uralian Foredeep, and from various Pennsylvanian formations of central and southwestern USA, we were able to add several details to the above characteristics of this species. The lingual rim of the base seems to be “ angular ” in the holotype only because of partial abrasion. In most other specimens the lingual torus is trapezoidal indeed, but with the angles definitely rounded. In the type specimen, the basolabial projections differ in shape and size from the buttons. The former are smaller, with almost flat basal surfaces, whereas the surface of the buttons is more rounded. However, it was noted from several specimens that the buttons and projections can be almost equal in diameter. The buttons are not always circular, but they can be oval; usually they are situated rather close to the lingual rim (Fig. 2 B 1). On the aboral surface, a mesio−distal furrow occurs lingually to the basolabial projections. The median cusp is relatively wide, with almost parallel lateral edges in the middle part (Fig. 1 C). The lingual face of the median cusp is considerably convex, covered with moderate, subparallel, vertical, only slightly curved cristae (Fig. 2 A). The labial face is deeply depressed basally, then becomes almost flat to slightly convex near the tip. The sculpture of the labial face is specific (see especially Glikman 1964 b: pl. 3: 10): the cristae which begin at the basal depression, close to the midline, first turn slightly outwards, but at the midpoint of the cusp they become vertical and then turn back inward, parallel to the edges of the narrowing cusp, and gradually fade. The cristae which start at the base but in more outward position, are almost vertical and intersect the lateral edges of the median cusp rather soon. The uppermost part of the cusp on both labial and lingual sides is smooth (Figs. 1 C, 2 A). The outer lateral cusps can be quite robust, but usually rather short. It appears that in all known specimens of this species, there is no more than one intermediate cusplet in the crown. A feature, characteristic of the whole genus, but particularly typical of G. occidentalis, must be emphasised here: because of the great depth of the basolabial indentation, framed by two projections, the intermediate cusplets are not in line with the median and outermost cusps, but are substantially displaced labially (Figs. 1 D, 2 B 1). Remarks. — The long synonymy list reflects the complex history of understanding this species, from the mid− 19 th century up to recent times. Probably the first specimen representing this species, from the Coal Measures of Coalbrook Dale in England, was illustrated by Prestwich (1840: pl. 41: 12), under the name of Hybodus. No description of the tooth is provided and the woodcut, although very good, is slightly simplified. The artist drew an undivided basolabial rim, without any sign of basolabial projections, therefore the tooth looks like Cladodus bellifer. However, the original which is available for investigation at The Natural History Museum, London (P. 7364), clearly shows an outline of a basolabial projection, typical of Glikmanius, on the preserved side of the base (Fig. 1 E). In 1859, Leidy’s brief, but clear description of the type specimen of Cladodus (now Glikmanius) occidentalis, was published in the Proceedings of the Academy of Natural Sciences of Philadelphia. However, because he did not illustrate his new species, Leidy’s note apparently went unnoticed both by J. S. Newberry and O. H. St. John. Therefore, the latter used Newberry and Worthen’s (1866) name, “ C. ” mortifer, for the specimens he presented in his reports on Carboniferous vertebrates from Nebraska (St. John 1870, 1872). To clarify the priority situation, Leidy (1873) gave a longer description and illustrated his type specimen, synonymising “ Cladodus ” mortifer sensu St. John with “ C. ” occidentalis. That does not necessarily mean that the holotype of “ C. ” mortifer sensu Newberry and Worthen belongs in Glikmanius occidentalis, because the tooth is apparently lost and its drawing (Newberry and Worthen 1866: pl. 1: 5) does not show diagnostic features. Meanwhile, Trautschold (1874), evidently unaware of the discussion among American palaeontologists in the early 1870 − s, described specimens of G. occidentalis from the vicinities of Moscow under another name from Newberry and Worthen’s (1866) paper, this time, “ Cladodus ” lamnoides (for photographic illustrations of Trautschold’s specimens, see Fig. 2 A and Ginter 2002: fig. 1 D – F). This mistake was noticed and corrected by Branson (1916: p. 653). From that time, until 1985, such forms were usually referred to as Cladodus occidentalis, with the exception of Glikman (1964 a, b) who proposed the ctenacanth affinity of this species. Williams (1985) applied Cope’s (1893) name Symmorium reniforme to such teeth from the Pennsylvanian Black Shales. This unfortunate decision influenced many later authors for more than a decade, but the revision of the type material of S. reniforme (Ginter 1998, 2002) definitely showed that teeth of the latter species are different in important aspects from those of G. occidentalis. They do have large median cusps and kidney−shaped bases, but such characters are insignificant, since they are typical of almost all cladodont sharks, with exception of Heslerodus and, perhaps, certain advanced stethacanthids. It should be noted that one of the best collections of G. occidentalis teeth, from the Council Grove Group (Lower Permian) of Wabaunsee County, Kansas, is presented at Michael Everhart’s web page, http: // www. oceansofkansas. com / Leidy 1859. html. Distribution. — Pennsylvanian – Lower Permian marine deposits of USA (New Mexico, Arizona, Kansas, Indiana, Illinois, Ohio, Colorado); Pennsylvanian, Moscovian – Permian, Wordian (= Kazanian) of Russia (central and eastern Russian Platform, the Urals); Middle Permian of Japan (?).	en	Ginter, Michał, Ivanov, Alexander, Lebedev, Oleg (2005): The revision of “ Cladodus ” occidentalis, a late Palaeozoic ctenacanthiform shark. Acta Palaeontologica Polonica 50 (3): 623-631, DOI: 10.5281/zenodo.13620880
03FD879FFFC0FFF6FFA8B29CC23DF952.taxon	description	Figs. 2 C, 3.	en	Ginter, Michał, Ivanov, Alexander, Lebedev, Oleg (2005): The revision of “ Cladodus ” occidentalis, a late Palaeozoic ctenacanthiform shark. Acta Palaeontologica Polonica 50 (3): 623-631, DOI: 10.5281/zenodo.13620880
03FD879FFFC0FFF6FFA8B29CC23DF952.taxon	materials_examined	Original material. — The original description was founded on about 50 teeth from the Moscovian and Kasimovian of the Moscow and Riazan Regions in Russia. The holotype, PIN 1704 / 180 (Lebedev 2001, pl. 41: 4 a), comes from the vicinities of the village of Myachkovo, Moscow Region; its stratigraphic position is uncertain: either Myachkovian Regional Stage, Moskovian, or Krevyakinian Regional Stage, Kasimovian. New material. — 28 teeth, CM 44549, from Peru, Nebraska, Indian Cave Sandstone, Onaga Formation, Upper Pennsylvanian; generally well preserved, with only slight traces of overall abrasion. Two teeth partly embedded in white limestone, MB. f. 9452.1 − 2, from the type locality at Myachkovo, probably Moscovian. Specimens belonging to the same species were described by Nekrylov (1997) as “ Cladodus ” sp. and Keltsiyan (2002) as “ Symmorium ” sp. Material studied by these two authors includes about 200 unnumbered teeth in the collection of the Geography Department of the Lugansk Pedagogical University (Lugansk, Ukraine) from the Gurkovaya Ravine close to Kalinovo village, Popasnya District, Lugansk Region, Ukraine. The age of the fossil−bearing layer is regarded as limestone M 7 1, Formation C 2 7 according to the local Donetsk Basin stratigraphical scheme (corresponding to the Podolskian – Myachkovian Regional Stages of the Russian Platform General unified scheme), Moscovian, Middle Carboniferous (Nekrylov 1997; Keltsiyan 2002). Material from this collection was examined by one of the authors of the present paper (O. L.) and is currently under description by V. Keltsiyan (Lugansk, Ukraine). Description. — This species of Glikmanius is characterised by small teeth with a relatively long and narrow median cusp and in most cases more than one, usually two to three, intermediate lateral cusplets on each side, smaller than the outermost ones. All the cusps in the crown are more in line than in G. occidentalis. The basolabial depression, projections, and rounded oral−lingual buttons are relatively weakly developed. The buttons are rather far from the lingual rim and can be connected by a thin and vague ridge. The part of the base lingual to the line connecting the buttons is folded downwards. The level of heterodonty in this species is rather low. However, several differences, particularly between smaller and larger teeth in the collection, can be pointed out. The smaller teeth (2 – 4 mm in the mesio−distal dimension) often have more than two intermediate cusplets on each side (up to four; Fig. 3 A); the larger ones (4 – 6 mm; Figs. 2 C, 3 C, F) have one or two such cusplets, and in the latter case the more lateral cusplet is the higher (Fig. 3 C 2, C 3, F 2). There are specimens, usually of intermediate size (3 – 4 mm), which possess more cusplets on one side than on the other, e. g., two and three or three and four (Fig. 3 B 2, E). Because the teeth are otherwise virtually symmetrical, it is impossible to say, whether the larger number of cusps is strictly side−related. The ornamentation of the median cusp is typical of Glikmanius, with only a few vertical cristae in the lower half and a smooth upper part of the labial side, whereas the lingual side is covered with 12 and more cristae, almost reaching the tip (Fig. 3 C 1, F 1). There is a single specimen in the collection from the Peru site, in all aspects of form resembling typical teeth of G. myachkovensis, but much larger than the rest. It is broken, but when complete must have measured well above 1 cm across the base. We think that it belonged to a particularly large individual of the same species. Comparisons. — The teeth of G. myachkovensis are consider− Some other teeth figured by Lund (1985: fig. 8) are also ably smaller than G. occidentalis, with a more slender, uni− similar to G. myachkovensis, but their possible relationship is formly narrowing median cusp throughout its length, and even less certain than in the case of that mentioned above. usually with a larger number of intermediate cusplets which The large tooth in Lund (1985: fig. 8 E) probably belongs to are more in line than in the other species. The basolabial de− “ Cladodus ” striatus Agassiz, 1843. pression is shallower in G. myachkovensis, the buttons are Distribution. — Upper Carboniferous, Pennsylvanian of the less prominent, situated further from the lingual rim, and of− Moscow Syneclise, Donetsk Basin, and Nebraska. ten connected with a low ridge; the latter feature is rather rare in G. occidentalis. Also the sloping lingual part of the base is a diagnostic feature of G. myachkovensis. Discussion Remarks. — This small form of Glikmanius was first noted by Ossian (1974) in the Peru site in Nebraska in his unpublished There are several taxa, whose tooth morphology is close to dissertation. He attributed an enormous number of such teeth Glikmanius gen. nov. Two of them, viz. Heslerodus diver− (1325), which he found at Peru, to the upper dentition of gens (Trautschold, 1879) (= Phoebodus heslerorum Wil− Cladodus occidentalis. He also decided to include consider− liams, 1985) and “ Ctenacanthus ” costellatus Traquair, 1884, ably different teeth (467), with three almost equal main cusps, share general basal features with Glikmanius, such as the in the same species, as representing its lower dentition. We deep median depression, two pad−like basolabial projections consider the “ upper teeth ” to represent G. myachkovensis and and two prominent buttons, but their crowns are considerably the “ lower teeth ” as belonging to Heslerodus divergens. It is a different. Heslerodus has gentle, thin, phoebodont−like main tempting idea to treat G. myachkovensis and H. divergens cusps, with the central cusp only slightly larger than the laterteeth as coming from the same fish, because indeed there are als; that was the reason why Williams (1985) attributed it to several similarities, particularly in the structure of the base the genus Phoebodus. In the holotype of “ C. ” costellatus, (two buttons and basolabial projections, and the median de− there is only one imperfect tooth (Traquair 1884: pl. 2: 6), but pression). However, there exist quite a few contradictory argu− the second specimen, described by Moy−Thomas (1936; see ments. Firstly, the semi−articulated specimens of H. divergens Ginter 2002: figs. 4 A, 5), provides much better material for described by Williams (1985, under the name of Phoebodus comparison. Its teeth can have up to three pairs of lateral heslerorum) from the Pennsylvanian Black Shales of Indiana cusps, which can be observed in Glikmanius myachkovensis, are associated with only one type of tooth. Secondly, teeth of but all the cusps are in line and very coarsely ornamented H. divergens are, on average, smaller than those of G. myach− with cristae converging at various heights. Moreover, the kovensis. It is also notable that the number of G. myachko− teeth of “ C. ” costellatus and Heslerodus are much smaller, vensis teeth, collected by Ossian, is more than twice as large as on average, than those of Glikmanius. that of H. divergens, and the numbers are so extreme, that this On the other hand, the size and the tooth−crown form are observation is evidently statistically significant. This ratio in shared features of Glikmanius occidentalis and the Lower Carthe sample studied by us, housed at the Carnegie Museum, is boniferous Cladodus sensu stricto (as noted above, the re−esless striking (28: 19), but also in favour of G. myachkovensis tablishment of this genus is under way, Duffin and Ginter in teeth. press). In particular, the crown of C. bellifer (St. John and It is probable that a tooth from the Namurian of Bear Worthen 1875: pl. 4: 10), with its large, gently striated central Gulch in Montana, illustrated by Lund (1985: fig. 8 A, B) as cusp, and intermediate cusplets moved labially off the line Stethacanthus sp., belongs to some species related to G. connecting the bases of the main cusps, resembles that of myachkovensis (see Fig. 1 B for a similar tooth from the same Glikmanius. However, in this case the basal articulation delocality). It has two intermediate cusplets on each side, and vices are different: in Cladodus, instead of two buttons there is the other features are typical of Glikmanius. However, a single, slightly curved ridge, and instead of two basolabial Lund’s figure suggests that the more median cusplet is the projections, there occurs a long, unbroken shelf or parapet. larger, which is opposite to the situation observed in the teeth There are two more cladodont genera which have a deep from Peru. The tooth from Montana is much larger than the median basolabial depression in their teeth, two basolabial average size of G. myachkovensis teeth (the width of the base projections, and may or may not have two buttons. These are reaches 1.5 cm), but does not exceed the size of the largest Cladoselache Dean, 1894, and Squatinactis Lund and Zanspecimen from Peru. It also ought to be remembered that gerl, 1974. Although their tooth−bases are superficially simi− Lund’s specimen was collected as a macrofossil and speci− lar to those of Glikmanius teeth, examination reveals that the mens from Peru come from processed conodont samples. nature of the basolabial projections is different. The projec− The latter method usually reveals smaller teeth. tions in Cladoselache (Ginter 2002: fig. 4 B) and Squatinactis Ą (Lund 1988: fig. 1; MG, personal observations), as well as in “ Symmorium ” glabrum Ginter, 1999 (whose real generic assessment is yet undetermined), are simply specifically formed parts of the labial rim of the base; in contrast, such projections in Glikmanius, Heslerodus, and “ Ctenacanthus ” costellatus appear to be independent entities. This suggests that in the mentioned two groups of taxa the overall appearance of tooth−bases developed convergently. Despite our belief that Glikmanius possessed ctenacanthiform spines, there is no direct evidence on that. Therefore, Glikman’s (1964 a, b) decision to assign G. occidentalis as Ctenacanthus appears to be premature. The type species of Ctenacanthus, C. major Agassiz, 1837, is based on a fin spine from the Lower Carboniferous Limestone of the British Isles. It is probable, considering the size of the spine, that one of the big tooth−based cladodont taxa from the same formation, such as Cladodus mirabilis, is conspecific with C. major. However, no such undoubted association, indicative of which particular tooth form it could be, has yet been found. Therefore, the only shark possessing true Ctenacanthus fin−spines (sensu Maisey 1981) and associated teeth is C. compressus Newberry, 1889 (= C. clarki Newberry, 1889; see Dean 1909, Williams 2001), from the late Famennian Cleveland Shale of Ohio. Its teeth, although definitely similar to those of Cladodus sensu stricto, are also distinctly different from those of Glikmanius, e. g., by lacking two buttons and two basolabial projections. We temporarily refrain from defining a new family for Glikmanius sp. nov., because some more comparative work on presumably related genera must be done. However, the above discussion suggests that, of all mentioned taxa, such a family should also include Heslerodus and “ Ctenacanthus ” costellatus. In this paper, we could confidently distinguish only two species of Glikmanius from the Permo−Carboniferous. However, future detailed studies, particularly on the material from the Serpukhovian of Montana and Moscow Syneclise, may show that more species deserve to be recognised. Several specimens, such as “ Cladodus girtyi ” (Hay 1900: fig. 2) and a part of “ Cladodus lamnoides ” teeth figured by Trautschold (1874: pl. 28: 3 c – e), also differ in certain aspects from the classic model of G. occidentalis. It seems an irony that such a well known tooth form is known only from isolated teeth and never even a partial dentition was recorded. This makes an account of probable ontogenetic and position−related heterodonty, and distinguishing it from an inter−specific variation, virtually impossible.	en	Ginter, Michał, Ivanov, Alexander, Lebedev, Oleg (2005): The revision of “ Cladodus ” occidentalis, a late Palaeozoic ctenacanthiform shark. Acta Palaeontologica Polonica 50 (3): 623-631, DOI: 10.5281/zenodo.13620880
