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Re: New Jeholornis specimen



David Marjanovic wrote-

> I fear this, and most other sternal characters, is so strongly related to
> ossification, and therefore ontogenetic and/or individual variation, that
> I've thrown the presence and shape of the lateral processes out of my
> little analysis which was once based on the matrix in chapter 11 of
> Mesozoic Birds (now 40 taxa, 50 characters, and growing). *Eoalulavis*
> looks a lot more ordinary now. :-)

The amount of ossification is a valid kind of character too.  Eoalulavis has
a largely unossified sternum, but was adult.  I think sternal shape is quite
useful for basal bird phylogenetics, as it seems to vary between standard
clades in obvious ways and is one of the few characters that's easy to see
in line drawings.

> > I also cannot determine
> > the condition in Otogornis,
>
> >From the photo and drawing in Mesozoic Birds it's not possible... I think
> it's somewhere in the archives that Kurochkin found it to have the
> euornithine condition. But so far I haven't been able to find similarities
> between it and *Ambiortus* (though I don't have a good pic of the latter
> either, let alone a description...); e. g. *A.* has a procoracoid process,
> *O.* does not...

Kurochkin, 1999. The relationships of the Early Cretaceous Ambiortus and
Otogornis (Aves: Ambiortiformes). Smithsonian Contributions to Paleobiology.
89: 275-284.
I can get this from the UW library, but haven't yet.

> While I am at it, I found out that it doesn't say anywhere what that of
> *Longipteryx* looks like.

"There is a marked dorsal process near the proximal end of the coracoid."
This would be the convex scapular facet.

> > > While I am at it, what should I choose as an outgroup for an analysis
> > > of the above problem, without having to make a 500-character
> > > coelurosaur analysis out of it?
>
> I should have mentioned what the ingroup is... Archie, *Rahonavis*,
> *Shenzhouraptor/Jeholornis*, *Hulsanpes*, *Yandangornis* (neither of the
> latter two is redundant) and Avebrevicauda (without most Ornithurae,
> *Nanantius*, and probably I'll have to throw *Alexornis* out because I
> can't find information about it; it appears to be very incomplete anyway).

Alexornis' material really sucks, and it was described as a neoavian anyway.
Holotype- (LACM 33213) distal humerus
Paratype- (LACM 33213) distal humerus
Referred- (LACM 33213) proximal scapula, proximal coracoid, proximal ulna,
distal femur, proximal tibiotarsus, fragments
I could code Alexornis for your matrix if you want.

> While I am at it, there is a famous paper that I can't get soon: Sanz,
> Chiappe & Buscalioni: The osteology of *Concornis lacustris* (Aves:
> Enantiornithes) from the Lower Cretaceous of Spain, and a reexamination of
> its phylogenetic relationships, American Museum Novitates 3133, 1 -- 23
> (1995). It is famous because it found an Avisauridae consisting of
>
> +--*Concornis*
> `--+--*Neuquenornis*
>    `--+--*Soroavisaurus*
>       `--*Avisaurus* (both species)
>
> although at one more step it collapsed. This topology has never been found
> again, leading me to suspect that the (only pedal) characters that were
> used either have a more chaotic distribution or have somehow been ignored
> in later works. Therefore, could someone retype me the matrix or at least
> the character list?

1. metatarsal IV considerably smaller [than what?].
2. medial rim of metatarsal III's trochlea with strong posterior projection.
3. posterior surface of tarsometatarsus excavated.
4. tubercle on anterior face of metatarsal II.
5. metatarsal I J-shaped.
6. metatarsal IV's trochlea medially concave.
7. proximal articular surface anteriorly inclined.
8. dorsal surface of metatarsal III's midshaft strongly convex transversely.
9. distal end of metatarsal II strongly curved medially.
10. metatarsal II's trochlea broader than trochleas of metatarsals III and
IV.

Mononyku 00000 00000
Patagopt 00100 00000
Yungavol 1001? ?0001
Lectavis 1?11? ?00??
Avisa.ar 1111? 11111
Soroavis 11111 01111
Neuqueno 111?1 ??101
Avisa.gl 1101? 11111
Concorni 1???0 00101

Mickey Mortimer