Ancient ontogenies: larval development of the Lower Cretaceous anuran Shomronella jordanica (Amphibia: Pipoidea)

Abstract

The Lower Cretaceous anuran Shomronella jordanica (Pipoidea) is represented by an assemblage of nearly 300 tadpoles of different ages. The size of the assemblage allows a reconstruction of the larval ontogeny of this species. We describe the ossification sequence and growth rates of S. jordanica and present reconstructions of tadpoles at different stages. The ontogeny of the species seems to be similar to that of extant pipids in many aspects. Larvae are similar in shape and size to those of Xenopus laevis but lack the anterior barbels that are typical for all extant pipids. The ossification sequence is closer to that of pipids than to that of other anurans. We present evidence that suggests that this species was terrestrial as an adult, and we discuss the implications of these data for the evolution of anuran development.

Cranial Osteogenesis and Suture Morphology in Xenopus laevis: A Unique Model System for Studying Craniofacial Development

“…Onset of ossification is evident at Stages 52–54 ( Figure 1, I, J ). Prior reports suggested that the parasphenoid ossified soon after;[15], [23] however, we found that the otic capsules and axial column were the next to ossify. Based on our μCTs, parashenoid ossification was not evident until stage 59 ( Figure 2, G′ ).…”

Exceptionally preserved tadpoles from the Miocene of Libros, Spain: ecomorphological reconstruction and the impact of ontogeny upon taphonomy

“…Despite the high abundance of specimens, the Libros tadpoles represent only certain developmental stages (Gosner stages 30–41). A bias towards specific developmental stages has been noted in other exceptionally preserved larval anuran faunas (Chipman & Tchernov 2002; Maus & Wuttke 2002; Roček 2003); tadpoles from Enspel (Maus & Wuttke 2002) exhibit bias towards developmental stages similar to that of the Libros specimens. Both the earliest (embryos and hatchlings) and metamorphic developmental stages are absent in the Libros material.…”

The Palaeozoic Ancestry of Salamanders, Frogs and Caecilians

“…, 2004), and that the condition seen in pipoids and some microhylids, which have simpler larval jaws (Orton, 1957; Starrett, 1973) is derived, rather than primitive. Fossil larvae, known as early as the Lower Cretaceous (Chipman & Tchernov, 2002), already exhibit the general form of modern tadpoles (Fig. 26).…”

“… Two larval stages of the Lower Jurassic pipoidea frog Shomronella jordanica from the Lower Cretaceous. Reproduced from Chipman & Tchernov (2002). …”