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The fine structure of zooidal tubes in Sabelliditida and Pogonophora with reference to their affinity

100%

Urbanek A., Mierzejewska G.

Acta Palaeontologica Polonica

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1977

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tom 22

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nr 3

Organic tubes of Sabelliditidae are a characteristic element of Lower Cambrian faunas. They were commonly compared with tubes of sedentary polychaetes, until Sokolov (1965) suggested their close affinity with Recent pogonophores. The aim of the present paper is to verify the latter hypothesis through a better understanding of ultrastructural features of zooidal tubes in both groups considered. The ultrastructure of the tube in Sabelliditida recognized for the first time by Urbanek, 1976 (in press), reveals that the wall of the tube is composed of two almost homogenous layers - the outer one and the inner one, and of the middle distinctly laminar layer. Characteristic wrinkles on the outer surface of the tube are made solely of the outer layer which is almost homogenous or with faint traces of some lammiation. The tubes in all Pogonophora under study display an entirely laminar structure. Wrinkles observed on certain areas of the tube are due to foldings involving numerous layers of the tube wall. Earlier biochemical and ultrastructural data and results of our ultrahistochemical observations are indicative of the presence of chitin, proteins (probably sclerotins) and mucopolysaccharides in the pogonophore tubes. The above results contribute to a better knowledge of the organic skeleton in both groups in question, but the problem of sabelliditid/pogonophore affinities remains unresolved. The degree and specificity of resemblance recognized at the submicroscopic level is not sufficient to confirm or disprove the hypothesis on close relationship between both groups considered.

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Vestimenifera [Pogonophora] - zadziwiajace robakoksztaltne zwierzeta zyjace dzieki symbiozie z bakteriami chemoautotroficznymi

80%

Lesicki A.

Przegląd Zoologiczny

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1997

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tom 41

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nr 3-4

193-211

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Chaetopterid tubes from vent and seep sites: Implications for fossil record and evolutionary history of vent and seep annelids

70%

Kiel S., Dando P. R.

Acta Palaeontologica Polonica

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2009

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tom 54

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nr 3

443-448

Vestimentiferan tube worms living at deep−sea hydrothermal vents and cold seeps have been considered as a clade with a long and continuing evolutionary history in these ecosystems. Whereas the fossil record appears to support this view, molecular age estimates do not. The two main features that are used to identify vestimentiferan tubes in the fossil record are longitudinal ridges on the tube’s surface and a tube wall constructed of multiple layers. It is shown here that chaetopterid tubes from modern vents and seeps—as well as a number of fossil tubes from shallow−water environments—also show these two features. This calls for a more cautious interpretation of tubular fossils from ancient vent and seep deposits. We suggest that: current estimates for a relatively young evolutionary age based on molecular clock methods may be more reliable than the inferences of ancient “vestimentiferans” based on putative fossils of these worms; not all of these putative fossils actually belong to this group; and that tubes from fossil seeps should be investigated for chitinous remains to substantiate claims of their potential siboglinid affinities.

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Jak odżywiają się Pogonophora?

60%

Jura C.

Wszechświat

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1967

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nr 01

Ograniczanie wyników

2 Acta Palaeontologica Polonica

1 Przegląd Zoologiczny

1 Wszechświat

1 Dando P. R.

1 Jura C.

1 Kiel S.

1 Lesicki A.

1 Mierzejewska G.

1 Urbanek A.

1 2009

1 1997

1 1977

1 1967

The fine structure of zooidal tubes in Sabelliditida and Pogonophora with reference to their affinity

Vestimenifera [Pogonophora] - zadziwiajace robakoksztaltne zwierzeta zyjace dzieki symbiozie z bakteriami chemoautotroficznymi

Chaetopterid tubes from vent and seep sites: Implications for fossil record and evolutionary history of vent and seep annelids

Jak odżywiają się Pogonophora?