September 2, 2012 | 20
I’ve been drawing crocodylomorphs. Lots of them. Crocodylomorpha, as if you need reminding, is the archosaur clade that essentially includes all archosaurs traditionally dubbed ‘crocodilians’: the living crocodiles, alligators and gharials and all their fossil relatives. These animals were hugely diverse in the past, and hopefully you can get some idea of that diversity (by which I mean: morphological disparity) here…
I could talk about the nomenclatural issues concerning this group a whole lot – I mean, as goes the differences between the names crocodylomorph, crocodyliform, crocodilian and crocodylian (for previous discussion, see the article on dwarf crocodile anatomy), but that’s not why we’re here. We’re here because this illustration – and we’ll be seeing a lot more of it later on – depicts most (but not all) of the diversity present in Crocodylomorpha: that is, representatives of most lineages are shown here. In much simplified, approximate order (heading crown-wards in the cladogram), we’re talking about sphenosuchians, protosuchians, gobiosuchids, notosuchians, peirosaurids, tethysuchians, thalattosuchians, atoposaurids, goniopholidids, gavialoids, crocodyloids and alligatoroids (e.g., Bronzati et al. 2012).
The plan, then, is to discuss these animals – err, all of them – here in time. As every human surely knows, there just aren’t enough reviews of crocodylomorph and/or crocodyliform diversity out there in the literature: there’s Steel (1973), Russell & Wu (1998) and Naish (2001), but none are up-to-date, or comprehensive. Anyway, for now, I thought I should share one version of the picture I’ve done. And because the whole illustration, as used above, is too small to be of use for anything, here are enlarged versions of the different sections…
More soon! And due credit to Henry Peihong Tsai for the title of this article. For some previous Tet Zoo coverage of crocodylomorphs (wholly crocodyliforms, and mostly crocodylians), see…
Refs – -
Mario Bronzati, M., Montefeltro, F. C. & Langer, M. C. 2012. A species-level supertree of Crocodyliformes. Historical Biology DOI: 10.1080/08912963.2012.662680
Naish, D. 2001. Fossils explained 34: Crocodilians. Geology Today 17 (2), 71-77.
Russell, A. P. & Wu, X.-C. 1998. The Crocodylomorpha at and between geological boundaries: the Baden-Powell approach to change? Zoology 100, 164-182.
Steel, R. 1973. Handbuch der Paläoherpetologie. Part 16. Crocodylia. Gustav Fischer Verlag (Stuttgart).