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ITALIAN LIMESTONE MEETING



Today I finished and bound AND handed in my thesis which means I 
should be really happy and busy down at the pub getting the beers in. 
Alas, I have too much other stuff to do and it just doesn't work like 
that. Have just borrowed a copy of a new symposium volume: Renesto, 
S. (ed) _Third International Symposium on Lithographic Limestones_, 
Revista del Museo Civico di Scienze Naturali "Enrico Caffi", 
Supplemento al Volume n. 20., pp. 136.

Results from a symposium that was held at Bergamo, Italy, from 1-5th 
September 1999. Most of the papers are concerned with inverts, styles 
and types of preservation and overviews of lagerstatten assemblages, 
but there are a handful of tetrapod papers, some of which are 
EXTREMELY interesting. 

AVANZINI, M. New Anisian vertebrae tracks from the Southern Alps (Val 
d'Adige and Valle di Non - Italy).

Describes and figures a bunch of trackways thought to pertain to 
lepidosaurs and archosauromorphs, including possible rhynchosaur 
tracks and some chirotheriids (an ichnofamily, possibly made by 
things like rauisuchians). What's fascinating is some of the tracks 
preserve skin impressions: for the chirotheriid prints I see that the 
impression is of pebbled, non-overlapping scales (which is what we 
generally expect for archosauromorph skin). Have just learnt that 
there is a _Chirotherium_ ichnospecies called _C. rex_ (Peabody 
1948). Another 'rex' for my list!

DAL SASSO, C. and RENESTO, S. Aquatic varanoid reptiles from the 
Cenomanian (Upper Cretaceous) lithographic limestones of Lebanon.

More information on the dolichosaurid _Aphanizocnemus_ (first 
monographed by Dal Sasso and Pinna in 1997) with comments on what it 
might say about the affinities of snakes - discusses the distribution 
of some of Lee's characters - as well as info on two new 
'ophiomorph' specimens that might be basal snakes. Also some 
discussion of _Pachyrhachis_ and hints that dolichosaurids, rather 
than mosasaurids, might be the closest relatives of snakes. One of 
the dolichosaur specimens apparently has skin preserved - would be 
interesting to compare this with mosasaur skin impressions and 
snakes.

NOSOTTI, S. New findings of _Tanystropheus longobardicus_ (Reptilia, 
Prolacertiformes) in the Middle Triassic of Besano (Lombardy, 
northern France).

New specimens, including complete juvenile skeleton and some 
spectacularly well-preserved hind limbs. Amongst several new findings 
regarded manus and pes structure, Nosotti emphasises that the 
tanystropheid pes is quite compact and there is little potential for 
abduction of digit V, as argued by Wild (1973). There are accessory 
bony structures in elbow and knee joints: epiphyses or sesamoids? 
Nosotti says probably epiphyses. _Tanystropheus_ is regarded as 
poorly adapted for aquatic life, and designed overall for a 
terrestrial existence. Maybe the constraints of the long neck 
resulted in the aquatic lifestyle... but don't apply this speculation 
to sauropods:)

And the most interesting paper for all you theropod nerds.....

PEREZ-MORENO, B. P. and SANZ, J. L. Theropod breathing mechanism: the 
osteological evidence.

Authors assert that the methodology of Ruben et al. is questionable 
and that their interpretations are doubtful: they point out that the 
model lacked backing from SEM and scanning microprobe analysis. Crocs 
and theropod have very different pelvic morphologies (they discuss 
the mobile croc pubis). The big news is that new prepping of 
_Pelecanimimus_ reveals new thoracic structures for this animal: an 
enclosed thoracic box with well ossified sternal ribs articulating 
with sides of sternum and thoracic ribs. The ginglymoid articulations 
of the sternal and thoracic ribs indicate high kinetic ability of the 
laterally flattened chest "probably associated to a costal breathing 
mechanism", and costal ventilation is probably primitive for 
tetrapods. "Some groups, as mammals or derived crocodilians, have 
developed a singular, autapomorphic diaphragmatic lung ventilation 
[sic]".

RENESTO, S., TINTORI, A., LOMBARDO, C. and MARAZZI, B. A complete 
phytosaur (Reptilia, Archosauria) from the Norian (Late Triassic) of 
Lombardy (northern Italy).

This specimen, which was also talked about at the last Secondary 
Adaptations to Life in Water conference (Copenhagen, September 1999), 
is 4 m long, gracile and something like _Mystriosuchus_ but with a 
proportionally shorter rostrum. Strange: lower jaw seems to be longer 
than upper one.The limbs appear quite slender and small; the distal 
end of the very long tail is poorly ossified while fan-shaped haemal 
arches and caudally bent neural spines would apparently have 
stiffened the end of the tail. These features indicate that this 
animal was quite aquatic.

REYNOSO, V-H. A new lizard from the Early Cretaceous lagerstatten of 
Tepexi de Rodriguez, Puebla.

Mentions _Huehuecuetzpalli_, a squamate whose bizarre name was 
recently commented on by Martill and Naish (1999 - in 
_Geoscientist_). The new specimen regarded as a basal scincoid: can't 
say more, have run out of time. 

DARREN NAISH 
PALAEOBIOLOGY RESEARCH GROUP
School of Earth, Environmental & Physical Sciences
UNIVERSITY OF PORTSMOUTH
Burnaby Building
Burnaby Road                           email: darren.naish@port.ac.uk
Portsmouth UK                          tel: 01703 446718
P01 3QL                               [COMING SOON: 
http://www.naish-zoology.com]