- Tytuł:
- A new type of colony in Silurian (upper Wenlock) retiolitid graptolite Spinograptus from Poland
- Autorzy:
-
Kozlowska, A.
Dobrowolska, K.
Bates, D.E.B. - Powiązania:
- https://bibliotekanauki.pl/articles/22266.pdf
- Data publikacji:
- 2013
- Wydawca:
- Polska Akademia Nauk. Instytut Paleobiologii PAN
- Tematy:
-
new type
colony
Silurian
retiolitid graptolite
Spinograptus
Graptoloidea
Retiolitidae
Polska
paleontology - Opis:
- The new retiolitid species, Spinograptus tubothecalis, is described from the Colonograptus praedeubeli and C. deubeli biozones from two localities in Poland: a borehole on the East European Platform and the Holy Cross Mountains. This was a recovery phase after the severe Silurian Cyrtograptus lundgreni Event. The new species has a unique, previously undescribed form of finite rhabdosome. Unlike the species Spinograptus reticulolawsoni and S. lawsoni, in which the fi− nite rhabdosomes taper distally, its rhabdosome is parallel−sided with the two distal thecae developed as isolated tubes without genicular processes, with a small appendix between them. The new species also has preserved membranes of the sicula, thecae and ancora sleeve, similar to a few species of Spinograptus from the lower Homerian. Spinograptus tubothecalis, like Spinograptus clathrospinosus and S. spinosus, has paired reticulofusellar genicular processes on the pre−thecal ventral orifices, similar to but shorter than thecal processes. Transverse rods, a rare character in post−Cyrto− graptus lundgreni Event retiolitids occur in the new species in rudimentary form.
- Źródło:
-
Acta Palaeontologica Polonica; 2013, 58, 1
0567-7920 - Pojawia się w:
- Acta Palaeontologica Polonica
- Dostawca treści:
- Biblioteka Nauki
Artykuł