Home
Archive

RECORDS
  Browse
  Search
  Summarize


Tables
Graphics
Literature Cited
Glossary

View Details:  Prev Record   Next Record

Clade
Subclade Archosauria: Crurotarsi to Crocodylia 

Taxon Feedback
Taxon Poposauridae 
Nominal Author Nopcsa 1923 
2° Nominal Author  
Taxon Status active
inactive
Comments

Poposauridae was coined by Nopcsa (1923) and initially thought by most to reside within Saurischia and possibly Theropoda. Steel (1970), for example, placed Poposauridae and its sole species Poposaurus gracilis in Carnosaria within Theropoda. Better specimens soon after linked Poposaurus and closest kin with crurotarsal archosaurs. Recent description and discovery of much more complete remains pertaining to Sillosuchus (Alcober and Parrish 1997) and Shuvosaurus (Nesbitt et al. 2005) will impact greatly on the understanding and placement of this clade within Suchia.

Parrish (1993:302) included four genera but did not define Poposuridae. The active definition is stem-based and uses the nominotypical Poposaurus gracilis as an internal specifier. Poposauridae, Paracrocodylomorpha and Crocodylomorpha form a conditional node-stem triplet.

 
Potential Synonomy  

Active Phylogenetic Definition Feedback
Active Definition The most inclusive clade containing Poposaurus gracilis Mehl 1915 but not Crocodylus niloticus (Laurenti 1768). 
Shorthand > Poposaurus gracilis but not Crocodylus niloticus
Definitional Author Sereno 2005 
Definition Status original
textual substitution
first-order revision
second-order revision
Definition Type node
stem
Node-Stem Triplet yes
no
Other Triplet Taxa Paracrocodylomorpha, Crocodylomorpha 
Specifiers
Specifier A Poposaurus gracilis 
Specifier(s) B  
Specifier(s) C Crocodylus niloticus 
Qualifiers
+Taxon  
-Taxon  
Datum  
Taxonomic Content stem (entirely extinct)
crown (extant-bounded)
mixed (extant/extinct-bounded)
Publication Year 2005 

Inactive Taxon Status Feedback
Rejection Criteria junior synonym
historically polyphyletic
incomplete definition
no definition
apomorphy-based
redundant
other 
Critique  
 

Current Age Range Feedback
Earliest Record Carnian (228 Ma) 
Latest Record Norian (204 Ma) 
Range (My) 24 
Basis for Range The earliest record are the poposaurids Poposaurus gracilis, Lythrosuchus langstoni, and Chatterjeea elegans from Carnian-age formations in western North America (Long and Murry 1995) and Sillosuchus longicervix (Alcober and Parrish 1997) from similar age beds in Argentina. The latest records are early Norian in age (Long and Murry 1995). Dates are rounded to the nearest million, the earliest from the beginning of the stage and the latest from the end of the stage (Gradstein et al. 2004).