Portal of Graptolite and Pterobranch Hemichordates
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Graptolite Net | Graptolites & Graptoliters | Rhabdopleuroidea | Cephalodiscoidea | Crustoidea | Camaroidea | Tuboidea | Dendroidea | Graptoloidea
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-------Cephalodiscus graptolitoides was erected by P.N. Dilly (1993) as 17th Recent species of the genus
Cephalodiscus M'intosh, 1882 of the order Cephalodiscoidea (family Cephalodiscidae). The type specimens of this
form were colected in the region of the island of Lifou (New Caledonian Islands) in February 1989. They were found
encrusting the surface of the tubes of Vermiliopsis associated with Dendrophylia.
-------According to P.N. Dilly, "The specimens are orange in colour, consisting of a flattened crust of tissue containing
within it many separate sacs each containing a single adult zooid. The surface of the colony is remarkable for a
series of needle-like spines. These spines are up to 3.5 cm in length tapering from a maximum diameter about 0.5
mm at the base. They extend outwards at right angles to the surface of the encrusting coenecium and intercoenecial
tissue."
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P.N. Dilly's diagram suggesting the mechanism for the secretions of the spines by the zooids during excursions from
their coenecial tubes.
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ABSTRACT of P.N. Dilly's paper:
"A new species of pterobranch has been found that has
features that could resolve the longstanding arguments
by palaeontologists about how the fossil graptolites
produced their elaborate extra-corporeal homes. Many
complex and biologically highly unlikely solutions
previously proposed can be simplified. This animal is
probably classifiable as a graptolite and thus a living
fossil, representing a group thought to be extinct for
300 million years."
Dilly, P.N. 1993. Cephalodiscus graptolitoides sp.nov. a probable
extant graptolite. Journal of Zoology. London. 229, 69-78.
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P.N. Dilly's opinion on Cephalodiscus graptolitoides
was discussed in following papers:
Dilly, P.N. 1993. When is a graptolite not a graptolite? -
Lethaia 27:34.
Maletz, J. & Erdtmannn, B.-D. - Lebende Graptolithen? -
Leider nicht!. Paläontologie Aktuell 32: 50-51.
Mierzejewski, C. & Kulicki, C. 2002. Discovery of
Pterobranchia (Graptolithoidea) in Permian. - Acta
Palaeontologica Polonica 47, 169-175.
Rigby, S. 1993. Graptolites come to life. - Nature
362:209-210.
Svitil,K. 1993. It's alive, it's a graptolite. - Discover 14,
07.
Urbanek, A. 1994. Living non-graptolite. - Lethaia
27:18.Urbanek, A. 1994. When is a pterobranch a
graptolite ? - Lethaia 27:324.
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-------------P.N. Dilly's opinion on Cephalodiscus graptolitoides was discussed in following papers:
Dilly, P.N. 1993. When is a graptolite not a graptolite? - Lethaia 27:34.
Maletz, J. & Erdtmannn, B.-D. - Lebende Graptolithen? - Leider nicht!. Paläontologie Aktuell 32: 50-51.
Mierzejewski, C. & Kulicki, C. 2002. Discovery of Pterobranchia (Graptolithoidea) in Permian. - Acta Palaeontologica
Polonica 47, 169-175.
Rigby, S. 1993. Graptolites come to life. - Nature 362:209-210.
Svitil,K. 1993. It's alive, it's a graptolite. - Discover 14, 07.
Urbanek, A. 1994. Living non-graptolite. - Lethaia 27:18.Urbanek, A. 1994. When is a pterobranch a graptolite ? -
Lethaia 27:324.
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Graptolite Net web pages on Cephalodiscus and the Cephalodiscoidea
Classification of the fossil and Recent Cephalodiscoidea.
Cephalodiscus densus Anderson, 1907 - Recent form.
A "protective shell" around the larval cocoon of Cephalodiscus.
Cephalodiscus lutetianus Abrard et al. 1950 from the Tertiary of France
Cephalodiscus-like fibrils in Ordovician graptoblast fusellar tissue.
Pterobranchites Kozłowski, 1967 from the Ordovician of Poland.
Pterobranchites Kozlowski, 1967 - an aberrant graptolite ?
Melanostrophus Öpik, 1930 - an enigmatic hemichordate.
Ultrastructure of the Ordovician Cephalodiscus-like genus Melanostrophus.
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GRAPTOLITE NET
is edited and periodically updated by
Dr Piotr Mierzejewski
since 2002
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