Search the Community
Showing results for tags 'placodermi'.
-
This is the prep I just finished of Bothriolepis canadensis (Placodermi; Upper Devonian). The concretion was collected in 1966 and never prepped. Because there was not much surrounding matrix, I prepped the whole thing (dorsal and ventral surfaces). I made a formed cradle out of paleosculp for prep and for storage, as the skull is compressed and potentially susceptible to breakage while handling. This is how the concretion looked prior to prep (left is dorsal, right is ventral): I started prepping the ventral side first (I didn't know when I started which side was which). Here is a series of photos showing the prep of the ventral side: Here is a series of photos showing the prep of the dorsal side. A portion of the left pectoral fin, complete with marginal spines, is present. The anterior part of the orbital is intact. I think the large raised piece toward the rear of the skull is the nucal plate that has been dislodged. If one were to spin that around and place it towards the front of the skull, it would make up the posterior of the orbital. I think the mouth opening is also intact on the ventral side. Here is a composite photo showing before and after prep of both sides.
- 27 replies
-
- 20
-
- bothriolepis
- placodermi
-
(and 2 more)
Tagged with:
-
Red Hill is a site I first went to 10 years ago with my son, Ian who was 10 at the time. It is a very deep road cut into the uppermost part of the Catskill Formation representing a late Fammenian river system that was draining the Acadian mountains to the east and emptying into the inland sea in western PA and OH. It is one of a handful of sites in the world where Devonian tetrapods have been found. The site has fossil layers in both channel margin (red layers) and flood plain (gray-green layers) facies. While it is an active research site and groups go there under the understanding that anything of scientific importance will be donated to the museum, there is a lot there that is redundant in the collections and we've been able to retain. In 2014, Ian found an exceptionally preserved moderately large osteolepiform, Hyneria (Tristichopteridae). Some of the material went into the re-description of Hyneria, much we have been allowed to take home. Since then the project has expanded to a search for more tetrapod material using the jackhammer and generator the museum purchased. This may require multiple posts. I'll start with the jaws recovered over 2014/15 seasons. This lens containing most of the head from apparently a single individual. Here Ian is working with Ted Daeschler and Doug Rowe (site manager) of the Academy Of Natural Sciences in Philadelphia. Here are some images of the jaw material after removal and after prep by Fred Mullison of the ANSP. Lower left jaw after removal. This is the lower right jaw (right) and the vomer and very impressive fang. Amazingly, in 2016, we went back. I was leading a trip for DVPS. Ian found this amazing but poorly prepped jaw (I did this one). Here are a pair of cleithrums, about 29 cm long. The attachments for the scapulocoracoid are clearly visible between 17 and 21 cm. Here is part of the parietal shield. More to follow.
- 26 replies
-
- 15
-
- acanthodii
- actinopterygii
- (and 8 more)
-
Postcranial anatomy of arthrodira like Dunkleosteus?
Mahnmut posted a topic in General Fossil Discussion
Hello dear people, I wonder where to find information and reference-images on the postcranial skeleton of dunkleosteus or related species. You find images of their iconically armoured skulls everywhere, but not a hint of the "fishbones". Is there so little fossil record? I hope someone can give me a hint. Thanks, J- 2 replies
-
- dunkleosteus
- placodermi
-
(and 2 more)
Tagged with: