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Cratopipa novaolindensis nov. gen. et sp.Â
Ismar de Souza Carvalho, Federico Agnolin, Mauro A. Aranciaga Rolando, Fernando E. Novas & Josà Artur Ferreira Gomes de Andrade (2019)
A new genus of pipimorph frog (anura) from the Early Cretaceous Crato Formation (Aptian) and the evolution of South American tongueless frogs
Journal of South American Earth Sciences (advance online publication)
Highlights
We describe a new genus and species of Pipimorpha from the Crato Formation (Aptian, Early Cretaceous), Araripe Basin, Brazil.
Cratopipa novaolindensis nov. gen. et sp. is the oldest pipimorph fossil from South America.
Phylogenetic analysis resulted in the nesting of the new taxon within a previously unrecognized endemic South American clade.
The analysis sustains dispersal of pipimorphs between Africa and South America through an island chain or continental bridge across the Atlantic Ocean.
Abstract
Pipimorpha is a clade of tongueless anurans with a wide fossil record. Furthermore, the oldest South American fossils come from the Late Cretaceous (Cenomanian) of Patagonia, Argentina. The aim of the present contribution is to describe a new genus and species of Pipimorpha from the Crato Formation (Aptian, Early Cretaceous), Araripe Basin, Brazil. The new specimen consists of a nearly complete skeleton that shows several anatomical similarities with other fossils from South America. Phylogenetic analysis resulted in the nesting of the new taxon within a previously unrecognized endemic South American clade. Further, some traditional groupings within Pipimorpha were not recognized. The new phylogenetic analysis reinforces previous biogeographical hypotheses sustaining dispersal of pipimorph between Africa and South America through an island chain or continental bridge across the Atlantic Ocean.
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Only an abstract for now:
RaÃl O. GÃmez and ÂCeleste M. PÃrez-Ben (2019)
Fossils reveal long-term continuous and parallel innovation in the sacro-caudo-pelvic complex of the highly aquatic pipid frogs.
Frontiers in Earth Science (abstract only)
doi: 10.3389/feart.2019.00056
Within the already peculiar Bauplan of anurans, pipid frogs have evolved an array of bizarre features that are commonly linked to their highly aquatic lifestyle. Among the latter, there are several distinctive sacro-caudo-pelvic features shared by extant pipids, which have been regarded as evolutionary novelties taking part of a specialized fore-aft-sliding ilio-sacral joint. Pipids and their kin (pipimorphs) have a rich fossil record documenting 130 million years of uninterrupted evolution in aquatic environments, which, along with our current understanding of their phylogeny and recently available musculoskeletal data, allows us to inquire on the patterns and processes that have led to their distinctive sacro-caudo-pelvic system with a deep-time perspective. Here, we take a phylomorphospace approach based on discrete character matrices and a scaffold tree derived from recent studies, making comparisons of morphospace occupation between pipids and other anurans, and morphospace occupation, disparity, levels of homoplasy, and shared evolving characters between different groups and/or over time across pipimorphs. In doing so, we focus on trends of morphological diversification and discuss the potential role that ecological and developmental constraints might have had in driving the evolution of the sacro-caudo-pelvic complex of pipid frogs. Our main findings reveal a pattern of continuous and parallel innovation early in the history of pipids followed by arrested evolution of novel morphologies towards the Recent. The latter, in turn, is mirrored by rampant homoplasy in the ilio-sacral sliding joint among extant pipid frogs. This study highlights the importance of fossils in revealing macroevolutionary patterns that will be otherwise veiled based on neontological data alone.
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