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1

Avian cranial kinesis revisited

100%

Bock W. J.

Acta Ornithologica

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1999

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tom 34

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nr 2

115-122

An integrated, holistic analysis of the avian jaw apparatus within the system of avian cranial kinesis shows a complex series of movements of the two jaws, rather than just a simple opening and closing of both jaws. Because of the complex arrangement of the jaw muscles, birds have achieved different adaptive configurations of these muscles for various movement combinations. Specialization of the several jaw muscles are correlated, nevertheless, with independent movements of each jaw, such as the evolution of the M. ethmomandibularis in parrots for independent raising of the lower jaw and the M. pterygoideus retractor in several avian groups for independent lowering of the upper jaw.

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Late Viruan [Caradoc] polychaete jaws from North Estonia and the St.Petersburg region

67%

Hints O.

Acta Palaeontologica Polonica

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1998

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tom 43

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nr 3

471-516

An abundant, diverse and well-preserved fauna of jaw-bearing polychaetes (Annelida, Polychaeta, Eunicida) was recovered from the late Viruan (Caradoc) of eight borehole sections in North Estonia and the St. Petersburg region. Altogether 46 species are encountered. Two new genera, Incisipnon with type species I. incisus (Kielan-Jaworowska, 1966) and Estonioprion with type species E. maennili sp. n., and five new species (Incisiprion edentulus, Polychaetura kielanae, Ramphoprion bialatus, Ramphoprion peterburgensis, Estonioprion maennili) are introduced. In addition 17 new species are described under open nomenclature. The taxonomy is based on jaw apparatuses, fused or reconstructed ones. Many species found in Estonia have been previously described from the erratic boulders of Poland. The studied polychaete fauna was confined to the North Estonian Confacies, a shallow-water carbonate shelf, which constituted favourable habitats for Ordovician polychaete worms. The stratigraphical ranges of many prevalent polychaete species exceed the interval studied. However, a few species seem to be restricted to particular horizons and may be useful for stratigraphy. Polychaete assemblages of certain time intervals, characterized by very steady species composition and relative frequencies of different taxa, were spatially widespread within the North Estonian Confacies. Based on the changes in the assemblages, some stratigraphical levels, like the boundary beds of the Idavere and Jõhvi stages, can be traced within the study area. The jawed polychaete faunas of Baltica and Laurentia probably had several species in common during the Caradoc.

3

Burgess Shale-type fossils in Cambrian sandstones of the Holy Cross Mountains

67%

Masiak M., Zylinska A.

Acta Palaeontologica Polonica

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1994

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tom 39

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nr 4

329-340

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Hartmaniellidae - living fossils among polychaetes

67%

Szaniawski H., Imajima M.

Acta Palaeontologica Polonica

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1996

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tom 41

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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.

Ograniczanie wyników

3 Acta Palaeontologica Polonica

1 Acta Ornithologica

1 Bock W. J.

1 Hints O.

1 Imajima M.

1 Masiak M.

1 Szaniawski H.

1 Zylinska A.

1 1999

1 1998

1 1996

1 1994

Avian cranial kinesis revisited

Late Viruan [Caradoc] polychaete jaws from North Estonia and the St.Petersburg region

Burgess Shale-type fossils in Cambrian sandstones of the Holy Cross Mountains

Hartmaniellidae - living fossils among polychaetes