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MARINE REPTILES GET THEIR DUE



Well, sort of. At long last, the much awaited and severely delayed volume
ANCIENT MARINE REPTILES has appeared. Shock of all shocks, we even have a copy
down at the National Oceanographic Library, surely the first useful thing
they've ever done.

CALLAWAY, J.M. and NICHOLLS, E.L. (eds) 1997. _Ancient Marine Reptiles_.
Academic Press, pp. 501. 

In its hardback form (I hope a softback will come it), it's very un-cheap:
nearly 45 quid here. There are sections on ichthyosaurs, sauropterygians,
turtles, marine crocs and mosasaurs, then trends, biostratigraphy,
macroevolution etc. I was very much looking forward to Mike Taylor's
contribution but was disappointed to find that he has 'only' written the forward
(I wanted a big treatise on rhomaleosaurs or something!). However, the forward
is a superb historical overview of the importance of marine reptiles. These
things are finally getting the attention they deserve.
 
In all, there are 17 papers in the volume. As I was not allowed to take the copy
out of the library (sucks doesn't it), I could only photocopy bits, and as I'm
rather disheartened at the thought of spending 25 pounds on photocopying (yes,
that's how much it would cost) the whole book, I've only got introduction pages
with me. Here are some highlights..

CALLAWAY, J.C. A new look at _Mixosaurus_.

Presumably a review of the morphology and phylogeny of this genus. I wonder if
the _Phalarodon_-_Mixosaurus_ situation has been sorted out: preliminaries were
published in a 1992 abstract by Callaway and Brinkman I recall.

MCGOWAN, C. A transitional ichthyosaur fauna.

In recent years, God Chris has been publishing on some Late Triassic ichthyosaur
from Williston Lake, B.C., that exemplify Jurassic, rather than traditional
Triassic, characters. Forefin and cranial material resulted in the description
of _Ichthyosaurus janiceps_ - extending the range of this genus back to the
Triassic. _I. janiceps_ reminds me of _I. breviceps_ and another McGowan
Williston Lake taxon, _Hudsonelpidia_ (say it out loud Pete). Are we looking at
phylogeny or ecology? Anyhow, this new paper reviews the lot. 

STORRS, G.W. Morphological and taxonomic clarification of the genus
_Plesiosaurus_.

Those of you in the know will already acknowledge that _Plesiosaurus_ is perhaps
the ultimate tetrapod scrap-basket. Glenn's work in this field is therefore of
extreme importance and everyone loves it - this time round, he finds that the
only taxon that should stay in _Plesiosaurus_ is _P. dolichodeirus_. Everything
else is either indet. or must be given a new name. Bakker (1993) had a bit of
a go at this and resurrected some old names like _Seeleyosaurus_ and created new
ones like _Attenborosaurus_. In _JVP_ 16 (1996), Glenn created _Thallasiodracon_
for _P. hawkinsi_. The plesiosaurids are climbing (or flying?) out of the scrap-
basket at last.

CARPENTER, K. Comparative cranial anatomy of two North American Cretaceous
plesiosaurs.

Ken revealed a while back that he had found that _Elasmosaurus morgani_ was
different enough from _Elasmosaurus_ s.s. to deserve a new genus: it's now been
called _Libonectes_. This paper is an essential look at plesiosaur phylogeny:
Ken argues (as he did in the _Neues Jahrbuch_ paper on _Trinacromerum_ etc. [new
genus of pliosaurid _Plesiopleuron_ created there]) that elasmosaurids are
closest to polycotylids (previously grouped with pliosaurids) and that both are
plesiosaurid derivatives and thus part of a Plesiosauroidea. Pliosaurids are the
out-group. This differs from Bakker's (1993) phylogeny where elasmosaurids +
polycotylids were derived from pliosaurids (I think). 

BELL, G.L.  A phylogenetic revision of North American and Adriatic
Mosasauroidea.

It's becoming difficult to keep up with mosasaur phylogenies. The Adriatic spin
is a new one though: should be fun.

DENTON, R.K., DOBIE, J.L. and PARRIS, D.C. The marine crocodilian _Hyposaurus_
in North America.

First (?) good review of this taxon (maybe excepting Mook 1925 but I haven't
read that yet - I only got it last Sunday).

GASPARINI, Z. and FERNANDEZ, M. Tithonian marine reptiles of the eastern
Pacific. 

As reported at the last SVP, South America is producing some nice ichthyosaur
faunas that upset conventional models of global ichthyosaur diversity
(especially for the Late Jurassic - elsewhere ichthyosaurs are severely low in
diversity at this time). The Cuban area (it may even be Cuba, I can't remember)
has produced cryptoclidids and metriorhynchids. This new paper reviews the
Pacific margin marine reptile situation - Middle Jurassic assemblages are richer
than Lias but the Tithonian is the most diverse. There were cryptoclidids and
a bunch of other taxa: groups long regarded as virtually entirely Northern
Hemisphere (__because__.... we have a topsy-turvy world view!).

COLLIN, R. and JANIS, C.M. Morphological constraints on tetrapod feeding
mechanisms: why were there no suspension-feeding marine reptiles?

Chris McGowan referred to this work (as 'in press') in a 1996 paper on giant
temnodontosaurs, so its appearance is a boon. I haven't read it, but the idea
is a little perplexing - after all, there *were* suspension-feeding marine
reptiles: mesosaurs, (possibly) hupehsuchians (Carroll and Dong, 1991, even
restored _Hupehsuchus_ with a sort of baleen), cryptoclidid plesiosaurs and
_Aristonectes_. OK, they're not as specialised as mysticetes but they are
behaving analogously, albeit under different morphological and ecological
constraints. 

This volume is essential if you are interested in, or work on, marine reptiles.
But for students with no money, like me, it is not available for purchase in the
hardback form. My birthday is September 26th if anyone wants to buy it for me.

"Can't get over how different we look"
"Must be the uniforms"

DARREN NAISH