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1
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On the morphology and evolution of the Cucullograptinae (Monograptidae, Graptolithina)

100%
Urbanek A.
Acta Palaeontologica Polonica
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1966
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tom 11
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nr 3-4
A description is given of the structure, astogenetic development and evolution of the Upper Silurian Cucullograptinae. It is based on the material contained in the core samples from the Mielnik on the Bug (Eastern Poland) deep-boring and from the Baltic drift. The graptolites were prepared by dissolving the limestone and marly matrix in hydrochloric acid. For detailed study the specimens were bleached. The stratigraphic position and significance of the fauna investigated are discussed. The main trend in the evolution of sicula consists in its simplification and is interpreted as due to foetalization. In contrast with sicula, the evolution of thecae displays progressive changes which primarily consist in the development of apertural apparatus, connected, in most lines, with the elaboration of its secondary asymmetry. The biological significance of this pattern of evolution of thecal characters is discussed. The Cucullograptinae supply convincing evidence for the distal introduction of phylogenetic novelties which makes up a prevailing mode of evolutionary changes of astogeny in this group of moriograptids. Problems, related to the mechanisms of evolution and organization of graptolite colonies are discussed. Using the data, now available, tentative phylogenetic relationships within the group are established. An attempt is made to show some implications of these data in the problem of origin of the Cucullograptinae. Fourteen representatives (species and subspecies) of the Cucullograptinae are described in the systematic part. Four species and two subspecies are new.
2
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Agastograptus, a synonym of Plectograptus [Retiolitidae, Graptolithina]

100%
Kozlowska-Dawidziuk A.
Acta Palaeontologica Polonica
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2002
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tom 47
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nr 3
Agastograptus robustus Obut and Zaslavskaya, 1983, the type species of the genus Agastograptusis herein recognized as a species of Plectograptus. Large proximal lateral orifices are one of the significant characters of Plectograptus. P. robustus differs from the type species, Plectograptus macilentus Törnquist, 1887, in possessing paired apertural processes. Other species of Agastograptus have been assigned to three different genera: Spinograptus, S. clathrospinosus (Eisenack, 1951), S. munchi (Eisenack, 1951), Neogothograptus, N. balticus (Eisenack, 1951), and Cometograptus, C. nevadensis (Berry and Murphy, 1975). The main diagnostic feature used for Agastograptus, the spinoreticular paired apertural processes, is recognized as a species feature, characteristic mostly for Spinograptus, whereas the generic features are the arrangement of the proximal end, ventral walls, and ancora sleeve of the rhabdosome. Therefore the genus Agastograptus is a synonym of Plectograptus.
3
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A new graptolite, intermediate between the Tuboidea and the Camaroidea

100%
Mierzejewski P.
Acta Palaeontologica Polonica
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2001
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tom 46
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nr 3
A new tuboid graptolite, Camarotubus graptocamaraeformis gen. et sp.n., is described from a calcareous erratic boulder of middle Ordovician (Caradoc?) age from Poland. This encrusting form combines characters of both the tuboid and the camaroid graptolites, and is regarded as a purely morphological intermediate between them. This finding supports Kozłowski's (1949) concept of a close phylogenetic relationship between the orders Tuboidea and Camaroidea.
4
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Discovery of Pterobranchia [Graptolithoidea] in the Permian

100%
Mierzejewski P., Kulicki C.
Acta Palaeontologica Polonica
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2002
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tom 47
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nr 1
The fossil remains of a hemichordate exoskeleton, recognized as fragments of the stolons and their cyst−like swellings connected with the fusellar zooidal tubes, were derived by chemical isolations from Late Permian (Kazanian) mudstones of the Svalis Dome (central Barents Sea, Norway). These fossils, referred to as Diplohydra szaniawskii sp. nov., are the first undoubted representatives of the class Graptolithoidea found in Permian deposits. The genus Diplohydra Kozłowski, 1959, known previously only from the Ordovician and originally established as a thecate hydroid taxon, is reinterpreted as an aberrant member of the order Rhabdopleuroidea. This strange hemichordate, characterized by fusellar tubes distinctly narrower than stolon−like tubes and their swellings, reveals a certain degree of dimorphism in the stolon system. D. szaniawskii sp. nov. also displays some peculiar morphological features common to the Ordovician rhabdopleuroid genus Rhabdopleurites Kozłowski and the stolonoid genus Stolonodendrum Kozłowski.
5
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Autothecal morphs and dormancy in the camaroid graptolite Xenotheka

100%
Mierzejewski P.
Acta Palaeontologica Polonica
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2003
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tom 48
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nr 1
The camaroid graptolite Xenotheka klinostoma Eisenack, 1937 is described from the lower Llanvirn limestones of Gilbergabrottet, northern Öland, Sweden. Two distinct autothecal morphs are recognized: (1) normal morph (described for the first time), i.e. an autotheca with an unsculptured outer surface, devoid of both an outer lining and autothecal occlusion, and inhabited by an active zooid; and (2) sealed morph, i.e. an autotheca coated and occluded, provided with a sculptured outer lining made of a unique verrucose fabric, and inhabited by an inactive or dormant zooid. In addition, the existence of a hypothetical (3) unsealed morph or re−opened autotheca, devoid of an autothecal occlusion but provided with an outer lining, and inhabited by a reactivated zooid, is predicted. The sealed morphs may represent an adaptation which allowed their inhabitants to survive adverse conditions. The outer lining of Xenotheka is compared with a peculiar outer membrane found in the modern hemichordate Rhabdopleura, from the intertidal zone of Fiji, and with camaroid extracamaral tissue.
6

Graptolite-bearing sites in Poland - concept of protection. Im memory of Professor Roman Kozlowski

80%
Gonera M., Miskiewicz K.
Nature Conservation
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2002
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tom 59
5-18
7
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The ultrastructure, development, and systematic position of the graptolite genus Mastigograptus

80%
Bates D. E. B., Urbanek A.
Acta Palaeontologica Polonica
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2002
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tom 47
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nr 3
Fragments of rhabdosomes isolated by chemical treatment from an erratic boulder of Baltic origin and ?Middle Ordovician age, provisionally assigned to Mastigograptus aff. tenuiramosus (Wallcott, 1881) were studied with SEM. Although exceptionally well preserved, remains lack the thin−walled free portions of thecae. Rhabdosomes are provided with a strongly developed basal disc, short stem and many branched stipes. The latter consist of heavily corticalized chains of stolothecae with alternately disposed thecal bases. Stolothecae display a morphological gradient and increase in size and change in shape distalwards. The stolon system studied with SEM on naturally and artificially broken specimens, as well as traced through open thecal bases, reveals a regular triad budding but no stolon inside the stolothecal cavity. We tentatively suggest that crassal lining, recognized earlier by TEM studies, corresponds to an unusually inflated stolonal stolon, filling the entire thecal cavity and adhering tightly to stolothecal wall. The systematic position of Mastigograptus, a matter of long debate, seems to be defined by a number of structural features which imply a distinct difference between genus in question and all known orders of sessile graptolites. The order Mastigograptida nov. and the family Mastigograptidae nov. are proposed.
8
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Kirkigraptus, a new retiolitid graptolite from Poland

80%
Kozlowska A., Bates D. E. B.
Acta Palaeontologica Polonica
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2008
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tom 53
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nr 1
The new retiolitid graptolite Kirkigraptus inexpectans gen. et sp. nov., from the Neodiversograptus nilssoni Biozone of the Bartoszyce borehole, Poland is described. It is unique among the retiolitids not having a preserved virgella or ancora. Instead the most proximal structures are two round proxi−lateral lists, joining the two genicular lists of the first thecae, connecting the two sides of the rhabdosome. The lists are interpreted as a possible homologue of the distal edge of the ancora umbrella in typical retiolitids. The size of rhabdosome with large proximal lateral orifices, and the ventral panels of thecae with mid−ventral lists, are similar to those of Plectograptus, whereas the two ancora sleeve panels consisting of spaced horizontal lists only, resemble those of Valentinagraptus. It is possible that the new retiolitid may represent a new pattern of development of the proximal end of the rhabdosome, different from that in all other retiolitids.
9
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Evolution of the retiolitid Neogothograptus [Graptolithina] and its new species from the upper Wenlock of Poland, Baltica

71%
Kozlowska A., Lenz A., Melchin M.
Acta Palaeontologica Polonica
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2009
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tom 54
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nr 3
423-434
Neogothograptus reticulatus sp. nov. from the upper Homerian Colonograptus praedeubeli Biozone, and N. thorsteinssoni and N. alatiformis from the Lobograptus progenitor Biozone, are described for the first time from three localities: borehole, Baltic erratic boulder of East European Platform and Holy Cross Mountains of Poland. N. reticulatus, presently the oldest known species of Neogothograptus, is also tentatively identified from upper Homerian strata of southeastern Australia. The two other species are previously known only from Arctic Canada, and possibly China. The morphology of the Neogothograptus reticulatus rhabdosome, its appendix, thecal profile, densely reticulated rhabdosome and genicular hoods suggest a close relationship to N. eximinassa from Colonograptus ludensis Biozone. N. reticulatus and N. eximinassa are most similar to Gothograptus nassa, the earliest−known retiolitid to appear immediately following the Cyrtograptus lundgreni extinction event. The biostratigraphic position of N. reticulatus suggests it might be considered as a potential ancestor to all younger (Ludlow) species of Neogothograptus. Cladistic analysis, however, provides no direct support for such an interpretation and, instead, suggests that Baculograptus batesi may be the ancestor. The occurrences of Neogothograptus, as well as G. nassa, from a number of Silurian terranes mostly from low paleolatitude regions, but also from high paleolatitudes, demonstrate their tolerance to a broad range of paleoenvironments.
10
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Phyletic evolution and iterative speciation in the persistent Pristiograptus dubius lineage

71%
Urbanek A., Radzevicius S., Kozlowska A., Teller L.
Acta Palaeontologica Polonica
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2012
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tom 57
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nr 3
The paper focuses on patterns of the evolution of the simplest and longest−ranging (approximately 18 Ma) Silurian graptolite Pristiograptus dubius. The Pristiograptus dubius species group consists of the P. dubius stem lineage represented by a sequence of a number of subspecies displaying only small morphological changes as well as derivative species produced from the stem lineage by means of iterative speciation. This long raging graptolite lineage is the only one, apart of one retiolitid, which survived the most severe environmental event for graptolites, the Cyrtograptus lundgreni Event. Based on three−dimensional, isolated material two P. dubius groups taxa are distinguished. One group has an obtuse angle between the thecal lip and the succeeding thecal wall, the second group has a right or acute angle. Other characters differentiating P. dubius forms are: the shape of the apertural lips, differences in rhabdosome shape and size, and a different number of sicular rings. Sixteen species and subspecies of Pristiograptus from the East European Platform, Poland and Lithuania are discussed. Five new subspecies P. dubius magnus, P. dubius paezerensis, P. dubius praelodenicensis, P. dubius postfrequens, and P. dubius postmagnus are proposed.
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