RE: Fossil snake with legs

[John Scanlon <riversleigh@outbackatisa.com.au>]

Hi Mike,

I can answer that one, having spent part of today plugging it in (only 80.3%
missing data, somewhat worse than Eupodophis).

With the ?composite varanoid? outgroup there are 3 shortest trees; in 2 of
them it goes on the snake stem between Dinilysia and Scolecophidia; in the
other one it is a basal madtsoiid (Najash, (Yurlunggur, Wonambi)). 

The other variable taxon is Eupodophis, which pairs with Haasiophis in two,
just above it on the stem in the other. With the 4 varanoid taxa as outgroup
instead, there are five trees with the same sort of variation (but anilioids
group with scolecophidians in all of them!)  In short, an unresolved
polytomy with madtsoiids, Dinilysia, Najash and Serpentes - i.e. it?s one of
several basal lineages of terrestrial snakes, higher up than the
'pachyophiids'.

New Scientist (the website at least) has a decent photo of the sacral
region; other views of the braincase would help!  With better illustrations
I?ll be able to score more characters (e.g. I could now add ?tuber costae
present?), but I don?t think there?ll end up being a large gap between
Najash and Dinilysia (the ear region is nearly identical; the prootic is
shorter though, which is one of the characters pushing it up towards modern
snakes).

John
 
-----------------------------------------------
Dr John D. Scanlon
Palaeontologist, 
Riversleigh Fossil Centre, Outback at Isa
19 Marian Street / PO Box 1094
Mount Isa  QLD  4825
AUSTRALIA
Ph:   07 4749 1555
Fax: 07 4743 6296
Email: riversleigh@outbackatisa.com.au
http://tinyurl.com/f2rby


-----Original Message-----
From: Lee, Mike (SAM) [mailto:Lee.Mike@saugov.sa.gov.au] 
Sent: Thursday, April 20, 2006 5:09 PM
To: John Scanlon
Subject: Fossil snake with legs


 << File: nature04413.pdf >> 

Hi

You've probably been told about this already...

Now, if he'd plugged it into a decent matrix (yours) I wonder where it would
come out?

M.