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1
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Fossil chaetognaths from the Burgess Shale: A reply to Conway Morris [2009]

100%
Szaniawski H.
Acta Palaeontologica Polonica
|
2009
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tom 54
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nr 2
361-364
Walcott (1911) erected the new genus and species Oesia disjuncta and assigned them to the polychaete annelids, based on a small collection of similar fossils from the famous Middle Cambrian Burgess Shale. In 2002 I suggested that the species is “possibly related to chaetognaths” (Szaniawski 2002: 405). Later, after obtaining new photos of the specimens and making comparative investigations with the extant chaetognaths, I was able to describe many significant similarities, and came to the conclusion that O. disjuncta indeed is an ancestral chaetognath (Szaniawski 2005). This interpretation already has been accepted in several publications (Vannier et al. 2005; Ball and Miller 2006; Hu et al. 2007. Giribet 2008). Ball and Miller (2006: 594) confirmed not only its “... remarkable resemblance to modern chaetognaths” but also correctness of recognition of all its organs. They even reproduced a part of my illustration showing them (Ball and Miller 2006: fig. 2). Vannier et al. (2006: 629) combined the problem with the open question of the systematic position of another Burgess Shale fossil Amiskwia sagittiformis Walcott, 1911, and expressed their reservation based on “...the lack of clear evidence of a grasping apparatus...”. Only Conway Morris (2009) firmly disagreed with this diagnosis and even devoted a special “discussion” article addressing the issue. However, that article contains several ambiguities and misunderstandings which need clarification.
2
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Three new polychaete jaw apparatuses from the Upper Permian of Poland

100%
Szaniawski H.
Acta Palaeontologica Polonica
|
1968
|
tom 13
|
nr 2
Three new species of polychaete jaw apparatuses are described. They have been chemically prepared from Zechstein deposits, from bore holes in Northern Poland. The following systematic units have beien established: the monotypic family Kielanoprionidae n. fam. with Kielanoprion pomeranensis n. gen., n. sp., as well as Oxyprion compressus n.gen., n.sp. (Mochtyellidae Kielan-Jaworowska) and Atraktoprion eudoxus n. sp. (Atraktoprionidae Kielan-Jaw.). These apparatuses are compared with other apparatuses and fossil scolecodonts as well as with recent forms.
3
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Conodonts from the Tremadocian chalcedony beds, Holy Cross Mountains (Poland)

100%
Szaniawski H.
Acta Palaeontologica Polonica
|
1980
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tom 25
|
nr 1
Conodonts extracted by means of hydrofluoric acid from the Upper Tremadocian chalcedony beds of the Holy Cross Mts. are described. Two multielemental simple-cone apparatuses are recognized: Drepanoistodus deltifer pristinus (Viira) and Acodus? sp. Drepanoistodus deltijer (= Paltodus deltifer) Zone is subdivided into D. deltifer pristinus and D. deltifer deltifer Subzones. Correlation of the subzones over northern Europe, and approximate intercontinental correlation, are established. Possible differences in internal structure are recognized between the Tremadocian cordylodids and simple cones.
4
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Conodonts of the Upper Permian of Poland

100%
Szaniawski H.
Acta Palaeontologica Polonica
|
1969
|
tom 14
|
nr 2
Eight species of conodonts, assigned to five genera, are described from the Zechstein limestone horizon of the Werra cyclothem from Wejherowo I.G.-1 boring in Pomerania. Lonchodina vistulensis n.sp., Prioniodina lindstroemi n.sp. and Hibbardella baltica n.sp. have been erected as new species. The Zechstein conodonts have been compared with the conodonts being parts of so-called natural assemblages.
5
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The earliest known venomous animals recognized among conodonts

100%
Szaniawski H.
Acta Palaeontologica Polonica
|
2009
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tom 54
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nr 4
Conodonts, a large group of tiny extinct marine animals ranging in age from the Late Cambrian to Late Triassic (ca. 500 to 200 Mya), are usually considered as jawless vertebrates. Their only commonly occurring fossilized remains are minute, phosphatic, teeth−like elements of their feeding apparatuses. In most of the early conodonts the elements were conical and strongly elongated. Many of them are characterized by possession of a deep, longitudinal groove, usually associated with sharp edges or ridges. A comparative study of the grooved elements and venomous teeth and spines of living and extinct vertebrates strongly suggests that the groove in conodonts was also used for delivery of venom. Structural convergence of the conodont apparatus Panderodus with the grasping apparatus of chaetognaths, a group of extant, venomous invertebrate predators of similarly ancient origin, provides additional support for this conclusion.
6

Poznanie stanowiska systematycznego konodontow - wielkie odkrycie paleontologiczne XX wieku

100%
Szaniawski H.
Kosmos
|
1996
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tom 45
|
nr 4
645-656
7
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Some Mesozoic scolecodonts congeneric with Recent forms

100%
Szaniawski H.
Acta Palaeontologica Polonica
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1974
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tom 19
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nr 2
The principles of comparing the jaws of the fossil and Recent polychaetes are here discussed. A Jurassic jaw apparatus is described and assigned to the Recent genus Ophryotrocha. Other jaws of polychaetes not having composite apparatus are assigned to Recent genera Glycera and ?Goniada. It has been found that the Paranereites, a scolecodont genus common in the Mesozoic, is a synonym of the genus Glycera. Other scolecodonts, considered by some authors as ancestors of the Recent genera Nereis and Glycera, are not closely related to these polychaetes. The generic assignment of the Mesozoic scolecodonts, usually included in the genus Goniada, is not certain. It has also been found that the Mesozoic polychaetes are more closely related to the Recent rather than the Palaeozoic genera.
8
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Jaw apparatuses of the Ordovician and Silurian polychaetes from the Mielnik borehole

100%
Szaniawski H.
Acta Palaeontologica Polonica
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1970
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tom 15
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nr 4
Fifteen jaw apparatuses of polychaetes from the Ordovician and Silurian of the Mielnik boring on the Bug are described. They include eight known species, three species identified to the generic level and four new species; Mochtyella duplicidentata n. sp., M. fragilis n. sp.; M. multilamellata n. sp. and Skalenoprion bugensis n. sp. The Ordovician assemblage of polychaetes differs fundamentally from the Silurian one and is much richer. The genera Rhytiprion Kielan-Jaworowska, Polychaetura Kozłowski, Ramphoprion Kielan-Jaworowska, Kalloprion Kielan-Jaworowska, Leptoprion Kielan-Jaworowska and Pistoprion Kielan-Jaworowska are known from the Ordovician only, while Paulinites Lange is most common in the Silurian deposits.
9
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Siluro-Devonian of Podolia, Ukraine: Paleobiological, biostratigraphic, and geochemical aspects

100%
Szaniawski H.
Acta Palaeontologica Polonica
|
2012
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tom 57
|
nr 4
10
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New evidence for the protoconodont origin of chaetognaths

100%
Szaniawski H.
Acta Palaeontologica Polonica
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2002
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tom 47
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nr 3
An earlier hypothesis concerning the origin of chaetognaths from protoconodonts found additional support in new discoveries and in recent structural, chemical and molecular investigations. The new findings show that the head armature of protoconodonts was composed not only of grasping spines but also of much smaller spicules corresponding in size and shape to the chaetognath teeth. Grasping spines of protoconodonts were originally built mainly of an organic substance. Their original composition was changed by secondary phosphatisation. The thickest layer of the protoconodont spines was originally constructed of organic fibrils, similar to those in the corresponding layer of chaetognaths. Recent molecular investigations show that the chaetognath lineage separated in the early stage of metazoan radiation, which fits the presented hypothesis. Described are some previously unknown structural details of chaetognath grasping spines, including composition of the outer layer and the origin of their distinctive tips.
11
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Cambrian chaetognaths recognized in Burgess Shale fossils

100%
Szaniawski H.
Acta Palaeontologica Polonica
|
2005
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tom 50
|
nr 1
Oesia disjuncta, one of the species of the soft−bodied fauna collected and described by Walcott (1911) from the Middle Cambrian Phyllopod Bed (Burgess Shale, British Columbia, Canada) is recognized as a chaetognath. For anatomical comparisons many specimens of Recent chaetognaths were specially compressed and dried to obtain forms similar to the fossils preserved in shales. The most characteristic features shared by the fossil and Recent specimens include: strongly elongated, transversely striated and very flexible body, large size, and characteristically diversified shape of head, pronounced intestine and horizontally oriented caudal fin. Possible traces of other chaetognath structures—grasping apparatus, lateral fins, seminal vesicles, ventral ganglion, ovaries and anus—are also present but preserved in one specimen only. Among extant genera, those showing the closest similarity to Oesia Walcott, 1911 are the hyperbenthic Archeterokrohnia Casanova, 1986¹, and Heterokrohnia Ritter−Záhony, 1911, which are considered by some authors as evolutionarily most primitive.
12
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Polychaete jaw apparatuses and scolecodonts from the Upper Devonian of Poland

63%
Szaniawski H., Wrona R. M.
Acta Palaeontologica Polonica
|
1973
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tom 18
|
nr 3
From Frasnian strata pierced by the Opole Lubelskie borehole in the south-eastern Poland, 10 polychaete jaw apparatuses are described. For these apparatuses, 7 new species and 3 new genera are proposed: Multiprion opolensis n.gen., n.sp., Mochtyella kielanae n.sp., Xanioprion walliseri n.sp., Processoprion longiprocessus n.gen., n.sp., Polychaetaspis hindei n.sp., Kielanoprion elleri n.sp., and Hindeoprion basalaris n.gen., n.sp. Moreover, 4 new species and 3 new genera of isolated polychaete jaws are described: Langeites lublinensis n.sp., Trianguligenys n.gen., Uncinogenys uncinatus n.gen., n.sp., Serratula minutidentata n.gen., n.sp., and Serratula longidentata n.sp. The problems of taxonomy of fossil polychaetes are discussed and necessity of further application of two independent systematics, one for scolecodonts and other for jaw apparatuses, is emphasized.
13
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New ischnacanthiform jaw bones from the lower Devonian of Podolia, Ukraine

63%
Voichyshyn V., Szaniawski H.
Acta Palaeontologica Polonica
|
2018
|
tom 63
|
nr 2
Investigation of fish fauna assemblages obtained by dissolution of calcareous rock samples from Early Devonian marine deposits of Podolia revealed new material of ischnacanthiform jaw bones. One family Podoliacanthidae fam. nov. and two new genera and species, Drygantacanthus semirotunda gen. et sp. nov. and Kasperacanthus serratus gen. et sp. nov., are established. The new family is based on one main key feature, the presence of denticle groups of Podoliacanthus type situated on the lingual tooth row. The family comprises three genera, Podoliacanthus, Drygantacanthus gen. nov., and Kasperacanthus gen. nov., as well as one new form undetermined to generic level. Another new form described in open nomenclature displays the remains of the most powerful known jaws among Podolian ischnacanthids known to now. The new forms have diverse main teeth morphology, which probably reflect differentiated hunting methods.
14
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Lochkovian conodonts from Podolia, Ukraine, and their stratigraphic significance

63%
Drygant D., Szaniawski H.
Acta Palaeontologica Polonica
|
2012
|
tom 57
|
nr 4
In the Podolian Dniester Basin (southwestern Ukraine) the Lower Devonian marine deposits are represented by about 530 m thick continuous sequence of interlaminated carbonate and schale outcrops at several localities. Conodonts occur in most of the carbonate layers of the whole Lochkovian but are not abundant and their ramiform elements are mostly broken or lacking. Therefore, only the pectiniform, Pa elements of twenty five stratigraphically important conodont species occurring in the region are discussed and two new species, Caudicriodus schoenlaubi and Pandorinellina? parva are proposed. The hypothetical phyletic relationships within the main representatives of the icriodontid and spathognathodontid genera, Caudicriodus, Zieglerodina, and Pandorinellina? are traced. Comparison of the previously published and newly obtained data revealed discrepancies in the hitherto used interpretation of some of the conodont taxa and their stratigraphic ranges. Contrary to the earlier reports, Caudicriodus postwoschmidti does not occur in the lower Lochkovian but only in the middle part of the Chortkiv Formation, high above the Monograptus uniformis Zone. Based on new material and verification of the previous determinations, a modified scheme of the Lochkovian conodont zonation in Podolia is proposed. Conodont zones: Caudicriodus hesperius, C. transiens, C. postwoschmidti, C. serus, and ?Caudicriodus steinachensis are distinguished. The zones are correlated with conodont zonations in other regions—Barrandian, Cantabrian Mountains, Pyrenees, and Nevada. Biostratigraphy of the Siluro−Devonian transition and Lochkovian is integrated with the carbon isotope stratigraphy.
15
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Acanthodian jaw bones from Lower Devonian marine deposits of Podolia, Ukraine

63%
Voichyshyn V., Szaniawski H.
Acta Palaeontologica Polonica
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2012
|
tom 57
|
nr 4
Ischnacanthiform acanthodian dentigerous jaw bones from the Lower Devonian (Late Lochkovian) of Podolia are described for the first time. One new genus and one new species are established. Podoliacanthus gen. nov. is diagnosed as having small−sized jaw bones, the presence of specific accessory cusps/denticles on the medial side of teeth of the lateral tooth row, and groups of denticles forming the lingual tooth row. Podoliacanthus zychisp. nov. is distinguished in having elongated slender jaw bones and lateral teeth with one medial side denticle. Besides, three species are described in open nomenclature: Podoliacanthus sp. 1, while similar to Podoliacanthus zychi sp. nov., differs in having stronger posterior inclination of the teeth tips and presence of well developed flanges of the teeth, P. sp. 2 has quite robust jaw bones and teeth with two medial side denticles, and Podoliacanthus sp. 3 has small narrow jaw bones and teeth with three medial side denticles. Morphology of the lingual tooth row is considered to be a diagnostic feature of generic and higher taxonomic levels, while accessory medial cusps/denticles of the teeth are regarded as diagnostic features at species level. The new genus also occurs in Upper Silurian or Lower Devonian deposits of North Greenland. Preservation of the jaw bones possibly depends on their secondary mineralization.
16
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Hartmaniellidae - living fossils among polychaetes

63%
Szaniawski H., Imajima M.
Acta Palaeontologica Polonica
|
1996
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tom 41
|
nr 2
111-125
The jaw apparatus of the Recent eunicoid polychaete Hartmaniella erecta is closely similar to those of the Mesozoic species of Palurites. It is concluded that the family Hartmaniellidae originated in the late Palaeozoic from an ancestor close to the Paulinitidae and is qlosely related to Kielanoprionidae. The lineage shows an extremaly slow rate of evolution. Hartmaniellids have been abundant during the whole Mesozoic while its Recent representation is only a relic. Palurites jurassicus sp. n. is proposed.
17
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Early Devonian scolecodonts from Podolia, Ukraine

63%
Szaniawski H., Drygant D.
Acta Palaeontologica Polonica
|
2014
|
tom 59
|
nr 4
One of the most fossiliferous and thickest sections of the marine Lower Devonian deposits was, for the first time investigated for the content of polychaete jaws (= scolecodonts). They are represented by elements of five genera and at least nine species but are not abundant and mostly fractured. Only a fraction of the specimens are sufficiently well preserved to allow genus and species-level identification. However, in some of them even the microstructure of the jaw wall can be observed. Over 90% of the determinable specimens are represented by the jaws of paulinitids which mostly belong to three species known from the Silurian of the Baltic region. Additionally, mochtyellids, atraktoprionids, skalenoprionids and, in the lower part of the sequence, polychaetaspids have been recorded. Two new species are established—Polychaetaspis kozlowskii sp. nov. and Atraktoprion podolicus sp. nov. Status of the genera Oenonites Hinde, 1879 and Kettnerites is discussed. Lectotype of the first is not determinable to the species level, while holotype of the type species of the second is probably missing and not determinable after the original illustration.
18
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A reconstruction of three jurassic polychaete jaw apparatuses

63%
Szaniawski H., Gazdzicki A.
Acta Palaeontologica Polonica
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1978
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tom 23
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nr 1
From isolated scolecodonts three new species of jaw apparatuses of Jurassic polychaetes are reconstructed and described: Schistomeringos expectatus sp.n., Arabella diversimaxillata sp.n. and Notocirrus compositus sp.n. The reconstruction criteria are briefly discussed. The ultrastructures preserved on attachment surfaces of soft tissues of scolecodonts are described and shown to be very useful for the reconstruction of jaw apparatuses. Micromorphological comparison showed a striking similarity in structure between Jurassic and Recent jaws of the Schistomeringos Jumars.
19
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Conodonts from the Kapp Starostin Formation (Permian) of Spitsbergen

63%
Szaniawski H., Malkowski K.
Acta Palaeontologica Polonica
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1979
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tom 24
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nr 2
Sixteen morphologic forms of conodonts are described from four sections of Kapp Starostin Formation of Spitsbergen. One new genus and two new species are established (Sweetocrtstatus arcticus gen.n., sp.n., Neostreptognathodus svalbardensis sp.n.). The assemblage is considered to be stratigraphically corresponding to that one known from the Upper Leonardian and Lower Roadian of western United States. Affinity of Neostreptognathodus to Adetognathus and Idiognathodus is suggested and hypothetical multielement apparatus of the genus is presented. Two distinct conodont biofacies in Kapp Starostin Formation are defined and their depositional environment is discussed.
20

40 lat dzialalnosci Instytutu Paleobiologii im.Romana Kzlowskiego.

63%
Szaniawski H.
Przegląd Geologiczny
|
1994
|
tom 42
|
nr 01
43-48
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