Table 4. Comparative rib material analyzed.

Systematic Position	Taxon	Abb.	Ecol.	Coll. Nb. & Reference
Squamata	Varanus rudicollis	Vru	ET	MNHN AC 1983–6
	Varanus varius	Vva	ET	MNHN AC 1910–12
	Carentonosaurus mineaui	Ca	PAS	MNHN IMD 51
	Dallasaurus turneri	D		TMM 43209-1, [31]
	Clidates sp. (juvenile)	Cj	AS	UCMP 34536, [60]
	Clidates sp. (subadult)	Csa	AS	RMM 1287, [61]
	Clidates sp.	Ca	AS	RMM 1788, [31]
	Tylosaurus sp. (early juvenile)	Tej	AS	RMM 5610, [60]
	Tylosaurus sp. (late juvenile)	Tlj	AS	UW 1501.5, [60]
	Platecarpus sp. (late juvenile)	Plj	AS	UCMP 34781, [60]
	Platecarpus sp. (subadult)	Psa	AS	AMNH 1645, [61]
	Platecarpus sp.	Pa	AS	AMNH 1543, [11]
Thalattosuchia	Metriorhynchid indet.	Me	AS	MHBR 208, [58]
Crocodilia	Crocodylus sp.	Cr	PAS	Unnb., [62]
Pinnipedia	Phoca vitulina	Ph	AS	IPB M 60
	Zalophus californianus	Za	AS	ZFMK 49.98
	Mirounga leonine	Mi	AS	ZFMK 62.105
Cetacea	Balaenoptera brydei	Ba	AS	NSM M 32599

Abbreviations are as in Table 2. AMNHN: American Museum of Natural History, New York, USA; IPB: Institute for Paleontology, University of Bonn, Germany; MHBR: Muséum d’Histoire Naturelle du Havre, France; NSM: National Science Museum, Tokyo, Japan; RMM: former Red Mountain Museum, Birmingham, Alabama, USA (the collection is currently housed at the McWane Science Center, Birmingham, Alabama, USA); TMM: Texas Memorial Museum, Dallas, Texas, USA; UW: University of Wisconsin, Madison, Wisconsin, USA. The ontogenetic stage is indicated for non-adult specimens.