Palæos:		Unit 160: Temnospondyli
The Vertebrates		200: Limnarchia

Temnospondyli: Limnarchia

TETRAPODA
|--+--LEPOSPONDYLI
|  `--REPTILOMORPHA
|
Temnospondyli 
|--Edopoidea 
`--+--Euskelia 
   `--Limnarchia 
      |--Dvinosauria 
      `--Stereospondylomorpha 
         |--Archegosauroidea 
         `--Stereospondyli 
            |--Lapillopsidae 
            `--+--Rhinesuchidae 
               `--+--Capitosauria 
                  `--Trematosauria 
                     |--Trematosauroidea 
                     `--+--Metoposauroidea 
                        `--+--Plagiosauroidea 
                           `--+--Rhytidosteidae 
                              `--Brachyopoidea 

1. Archegosauroidea X
2. Dvinosauria X
3. Lapillopsidae X
4. Limnarchia X
5. Stereospondyli X
6. Stereospondylomorpha X

Descriptions

Limnarchia: 

Range: Permian to middle Cretaceous.

Phylogeny: Temnospondyli::: Euskelia + *: Dvinosauria + Stereospondylomorpha.

Characters: $ paraquadrate foramen on occipital face of quadratojugual; $ perforated anterior palatal fossa; $ ectopterygoid toothrow; $ pterygoid with conical recess dorsal to pterygoid - parasphenoid articulation; $ maxilla sutured to vomer; vomer denticles absent; $ discrete postglenoid area on mandible; relatively elongate interclavicle.

Links: Limnarchia after Yates & Warren, 2000; Phylogeny and Apomorphies of Temnospondyls; 

References: Yates & Warren (2000). 020414.

Range: Permian & Triassic

Phylogeny: Limnarchia: Stereospondylomorpha + *. 

Characters: $ otic notch reduced to shallow embayment; $ pterygoid, palatine ramus, postero-lateral flange absent; $ 28+ presacral vertebrae.

Links: Dvinosauria Yates & Warren, 2000; Phylogeny and Apomorphies of Temnospondyls. 

Notes: This is a diverse and interesting group, the smaller of the two temnospondyl clades which survived the Permian and radiated into the Triassic. 020414.

Stereospondylomorpha: The stereospondylomorphs are the more significant of the two temnospondyl groups which survived the Permian.  The name refers to the structure of the vertebrae, in which the intercentrum was the dominant or only component of the centrum (i.e. the pleurocentrum was absent).

Range: Early Permian to middle Cretaceous.

Phylogeny: Limnarchia: Dvinosauria + *: Archegosauroidea + Stereospondyli. 

Characters: $ Jugal extends anterior to orbit; $ prefrontal sutured to jugual; $ maxilla-nasal suture; $ "arcadian groove" on the postglenoid area of the mandible. 020414.

Range: Assellian - Wuchiapingian

Introduction: These are a diverse assemblage of mostly large to very large crocodile-like semi-aquatic Permian forms.  The constitute a transitional grade between the basal, rhachitomous temnospondyls and the more specialised aquatic families (Stereopondyls) which dominated the Triassic waterways.  

Characters: premaxilla without triangular process projecting posteriorly, medial to the naris; premaxilla with rugose, medial tubercle between anterior palatal fossae.  

Image: (skull) Platyposaurus from Gondwana Studios

Links:  Phylogeny and Apomorphies of Temnospondyls; PaleoNET | Библиотека (new Melosaurus species and revision of related taxa);    ATW030927.

Stereospondyli: 

Range: Late Permian to middle Cretaceous.

Phylogeny: Stereospondylomorpha: Archegosauroidea + *: Lapillopsidae + (Rhinesuchidae + (Capitosauria + Trematosauria))).

Characters: $ Lacrimals excluded from both orbit & nares [Y99]; $ pterygoid, palatine ramus posteriorly retracted; $ pterygoid with flat, broad internal process articulating with most of lateral edge of parasphenoid plate; $ pterygoid sutured to parasphenoid early in ontogeny; [Y99] $ pterygoid ornamentated on ventral surface; $ mandible with distinct post-glenoid region [Y99].

Links: Stereospondyli; Phylogeny and Apomorphies of Temnospondyls; The Lapillopsidae; Axial Skeleton; Untitled Document. 

References: Yates (1999) [Y99]. 

Lapillopsidae: Lapillopsis, Rotaurisaurus

Range: Early Triassic of Australia. 

Phylogeny: Stereospondyli: (Rhinesuchidae + (Capitosauria + Trematosauria))) + *.

Characters: small, semi-terrestrial; $ narrow pterygoid-parasphenoid articulation.

References: Yates (1999) [Y99] ATW030112. 

checked ATW060327