Ranidae, Batsch, 1796
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publication ID |
https://doi.org/ 10.4202/app.2011.0063 |
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persistent identifier |
https://treatment.plazi.org/id/03D287C7-835A-FFD1-BC64-C526FD9FF928 |
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treatment provided by |
Felipe |
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scientific name |
Ranidae |
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Family “ Ranidae View in CoL ” Rafinesque, 1814
“ Ranidae ” indet.
Figs. 7 View Fig , 8 View Fig .
Material.—Eight nearly complete ilia: GU/RSR/VAS 5202 ( Fig. 7 View Fig ), GU/RSR/VAS 5203–5209); seven vertebrae: GU/ RSR/VAS 5210–5212 ( Fig. 8A–C View Fig ), GU/RSR/VAS 5213– 5216; and two urostyles: GU/RSR/VAS 5218 ( Fig. 8D View Fig ), GU/ RSR/VAS 5217.
Description.—In lateral view, the iliac shaft is cylindrical and is separated from a high dorsal crest by a well−marked groove ( Fig. 7A View Fig ). The tuber superius, a thickening of the proximal (= anterior) part of the dorsal crest, is ovoid and projects slightly laterally ( Fig. 7D View Fig ). The junction between the acetabular area and the shaft is constricted. A shallow, small, rounded supraacetabular fossa is present at the proximal (= anterior) base of the tuber superius. The angles between the tuber superius and the pars ascendens and between the shaft and the pars descendens are both close to 90°. The pars ascendens is short. The pars descendens is broken on GU/RSR/VAS 5202, but was likely short and flared. The acetabulum is rounded and its border is accentuated by a sharp rim. There is no subacetabular fossa. In medial view, there is no distinction between the tuber superius and the dorsal crest ( Fig. 7C View Fig ). Two ridges extend along the pars ascendens and pars descendens. Proximally (= anteriorly), the dorsal crest and the iliac shaft are separated by a groove. There is no interiliac tubercle. In dorsal view, the dorsal crest is posterolaterally to anteromedially oriented on the shaft ( Fig. 7D View Fig ).
The posterior part of the presacral region of the vertebral column can be reconstructed. The vertebrae are not imbricate. The presacral vertebrae, except the last one, are procoelous and rather short antero−posteriorly ( Fig. 8A View Fig ); the neural arch bears a strong medial ridge and presents a notch on its anterior border that is anteriorly widened. The last presacral vertebra is amphicoelous, presenting an anterior and a posterior cotyle ( Fig. 8B View Fig ). The sacral vertebra is biconvex with two posterior condyles ( Fig. 8C View Fig ). The sacral diapophyses are well separated from the prezygapophyses, are posteriorly directed and are cylindrical (not laterally or antero−posteriorly expanded). This vertebra is also characterized by a well−developed medial ridge on the neural arch, which is laterally bounded by two well−marked and posteriorly concave ridges. The urostyle is free and presents two anterior cotyles and a well−developed dorsal crest ( Fig. 8D View Fig ; see Table 1).
Discussion.—Some ilia of this taxon present a tuber superius that is more elongated and anterodorsally oriented. The supraacetabular fossa is also deeper on some specimens. These differences are interpreted as intraspecific variations.
The presence of a dorsal crest, the acute angle between the tuber superius and the pars ascendens, the tuber superius that is a thickening of the dorsal crest, and the absence of an interiliac tubercle ( Prasad and Rage 2004) indicate that these specimens belong to a ranoid frog. These characters are also present in the ilia of Ranoidea indet. (IITR/SB/VLM−LV/ 201–202) described from Vastan by Bajpai and Kapur (2008), and both probably represent the same taxon.
The bicondylar sacro−urostylar articulation is consistent with a ranoid affinity ( Rage and Hossini 2000). This group is considered here to include families “ Ranidae ”, Rhacophoridae , “ Hyperoliidae ” and Microhylidae and excludes Dendrobatidae (sensu Cannatella 2007) .
The ranoid from Vastan differs from the ranoid described by Prasad and Rage (2004) from the Upper Cretaceous intertrappean beds of Naskal, India, by having a more constricted junction between the acetabular area and the shaft, and by the presence of a supraacetabular fossa. It also differs from the Microhylidae and the Rhacophoridae (except Mantidactylus , Buergeria , Chiromantis , Polypedates ; Liem 1970) and is close to the “ Ranidae ” and “ Hyperoliidae ” in the presence of a diplasiocoelous assemblage of the vertebrae (all vertebrae are procoelous, except the last presacral vertebra which is amphicoelous and the sacral vertebra which is biconvex; Liem 1970; Rage and Hossini 2000; Rödel et al. 2009). Moreover, it differs from the rhacophorids Buergeria , Chiromantis , and Polypedates by a more developed tuber superius and by a more acute angle between the tuber superius and the pars ascendens. It differs also from the Microhylidae and “ Hyperoliidae ” by the presence of a well−developed dorsal crest on the iliac shaft ( Nokariya 1983a; Scott 2005). Finally, following Rage and Hossini (2000), non−imbricate vertebrae, cylindrical sacral diapophyses and a free urostyle with a well−developed dorsal crest are a typical character assemblage for the family “ Ranidae ”. The ilium and vertebrae described above from Vastan can thus be attributed to “ Ranidae ”. The posterior border of the dorsal crest sloping precipitously into the dorsal acetabular area and the acute angle between the tuber superius and the pars ascendens are similar in general morphology to the green frog Rana clamitans ( Holman 2003) .
It might seem that the quantity and quality of the specimens assembled here should allow us to create a new taxon. However, below the familial level, there are few diagnostic osteological characters of the different “ranid” genera, which are mainly distinguished on external morphological characters. It is thus premature to create a new taxon or to include this material in an already existing taxon until there is a detailed revision of the family “ Ranidae ” that identifies generically distinctive osteological traits.
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