Saturday, February 07, 2009

It Has Palpebral HORNS!


This is not something you see every day. Notice that they are not postorbital horns--the little bastard has those, too. So it has six horns: Jugal, postorbital, and palpebral. That is one mean little parrot lizard. Also, I know I've been doling out short, "fun-size" posts lately. It's not like I don't have anything to post about. Specifically, I need to get on the Maiacetus bandwagon. Cthulhu and Einiosaurus have been taking up a lot of my time.
Also, Coraline is the best movie I've seen all year. It's also the only movie I've seen this year. But trust me, it's a magical film.

6 comments:

Sean Craven said...

You're teasing me, right? Sorry, man, I've got to go with a species with some accessible material dealing with the postcranial remains.

(Maybe I could do just a face...)

Coraline was swell, wasn't it? The missus dragged me to see it and I liked it more than she did. It pushed the envelope for a kid's movie -- which I dug.

I've got the book chasing around somewhere...

220mya said...

Why aren't they lacrimal horns? It is suspicious that Averianov et al (2006) state that no lacrimal was present among the isolated elements, and that they could not distinguish it on any of the articulated material.

Averianov, A.O., A.V. Voronkevich, S.V. Leshchinskiy, and A.V. Fayngertz. 2006. A ceratopsian dinosaur Psittacosaurus sibiricus from the Early Cretaceous of west Siberia, Russia and its phylogenetic relationships. Journal of Systematic Palaeontology 4(4):359-395.

Zach said...

Yeah, I guess it could be the lacrimal...

Raptor Lewis said...

I remember reading an article once, where Dr. Horner went to Monglia looking for these cute and primitive ceratopsians.

Christopher said...

They're not lachrymal horns because cearatopsian skulls aren't constructed like theropod skulls!

In Psittacosaurus, the lachrymal creates the anterior border of the orbit, but is entirely bordered dorsally by the prefrontal. The prefrontal creates the anteriodorsal corner of the orbit and is where the palpebral attaches. Theres no place for a lachrymal horn like you see in theropods. That quote from Averianov et al (2006)likely refers to the state of fusion, ie the sutures have been obliterated because ceratopsians like to do that, and the lachrymal cannot be distinguished separately.

220mya said...

Christopher - thanks for that explanation. Other than the fact that a palpebral is a great place to put a horn (i.e., it is a dermal epiossification, and most horns/spikes on ceratopsians are epiossifications), what is the evidence that these aren't prefrontal horns?