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News from both congresses



The Second International Phylogenetic Nomenclature Meeting at Yale (top left corner of http://www.ohiou.edu/phylocode) was very small (not much more than half as many participants as the first meeting 2 years ago), but it has been very productive. Most likely there will soon be an article on how to emend failed definitions without having to appeal to the Committee, and an article on species names that will basically leave them to the existing rank-based codes. The proponents of the "crown-clade convention" and the "*Pan-* convention" are softening up.

The Second International Palaeontological Congress in Beijing (http://www.ipc-2006.ac.cn) was very large (well over 700 participants, maybe 1000) and also very interesting. News on Mesozoic amniotes that I haven't reported yet:

- There now is a partial phylogeny of *Psittacosaurus*:
--+--+--*P. mongoliensis*
 |  `--*P. neimongolensis*
 `--+--*P. meileyingensis*
    `--+--*P. sinensis*
       `--*P. xinjiangensis*

- The species mentioned above are all valid and differ in growth trajectories (that is, they all grow allometrically, but not in the same way).

- There is a new species of *Psittacosaurus* from the fluviatile part of the Yixian Fm. Its name was mentioned. The referred (adult) specimen of *Hongshanosaurus* belongs to this species (so I can keep it in the database used for my thesis -- phew); the holotype of *H.* is not diagnostic because it is so juvenile and so distorted, making *H.* a nomen dubium.

- There is not one adult bone in the *Falcarius* bonebed. So my use of it in my thesis was a mistake.

- There is now a partial segnosaur phylogeny:
--+--*Falcarius*
 `--+--*Beipiaosaurus*
    `--+--+--*Erliansaurus*
       |  `--the arm referred to *Alectrosaurus*
       `--+--+--*Nothronychus*
          |  `--*Erlikosaurus*
          `--+--*Neimongosaurus*
             |--*Therizinosaurus*
             `--*Segnosaurus*

I don't quite remember if *Alxasaurus* was included.

- Jane is a fascinating subadult *T. rex*, and so is the type of *Nanotyrannus*.

- *Hongshanornis* has a sister-group in the Jiufotang Fm. No name was mentioned.

- There is a nearly complete lonchodectid specimen from the Jiufotang Fm. Lonchodectidae, Azhdarchidae, *Tapejara* and *Tupuxuara* are closely related. No name was mentioned.

- Baby pterosaurs, even in the egg, have wing loadings within the range of adult pterosaurs. This, together with the isometric growth (I reported) of wing finger length : wingspan and hindlimb length : wingspan, suggests that pterosaurs (or most of them anyway) were able to fly very soon and then grew rather slowly through several ecological niches.

- *Uchkudukodon*, the new mammal published shortly after the congress, has a saber-toothed sister-group that looks scary (complete skull with lower jaw preserved) from Mongolia. (No size was mentioned, but I suppose it is standard Mesozoic mammal size.) It pulls Asioryctitheria and IIRC Zhelestidae into Placentalia, next to Carnivora... based on the epipubes and stuff, I wonder if this will hold up, for example if any tooth characters turn out to be correlated or suchlike...

I hope that's all. If you are interested, I can hunt down and retype the abstracts.