A new paper:
[Note that this specimen was found in Cretaceous amber from Myanmar, a subject of major controversy over the conditions under which amber thereÂcurrently is mined and sold. Some journals have decided not to publish research based on amber from Myanmar. According to press material, however, "Specimens were acquired following the ethical guidelines for the use of Burmese amber set forth by the Society for Vertebrate Paleontology."]
Yaksha perettii gen. et sp. nov.
Juan D. Daza, Edward L. Stanley, Arnau Bolet, Aaron M. Bauer, J. Salvador Arias, Andrej ÄerÅanskÃ, Joseph J. Bevitt, Philipp Wagner & Susan E. Evans (2020)
Enigmatic amphibians in mid-Cretaceous amber were chameleon-like ballistic feeders.
Science 370(6517): 687-691
DOI: 10.1126/science.abb6005
https://science.sciencemag.org/content/370/6517/687Ancient amphibians preserved in amber
Extant amphibians are represented by three fairly simple morphologies: the mostly hopping frogs and toads, the low-crawling salamanders, and the limbless caecilians. Until the early Pleistocene--and for more than 165 million years--there was another group, the albanerpetontids. We know little about this group because amphibian fossils are poorly preserved, and previous specimens from this group are both rare and mostly badly damaged. Daza et al. describe a set of fossils preserved in amber showing that this group was unusual both in their habitat use (they may been climbers) and their feeding mode, which appears to have been convergent with the ballistic feeding now seen in chameleons (see the Perspective by Wake).
Abstract
Albanerpetontids are tiny, enigmatic fossil amphibians with a distinctive suite of characteristics, including scales and specialized jaw and neck joints. Here we describe a new genus and species of albanerpetontid, represented by fully articulated and three-dimensional specimens preserved in amber. These specimens preserve skeletal and soft tissues, including an elongated median hyoid element, the tip of which remains embedded in a distal tongue pad. This arrangement is very similar to the long, rapidly projecting tongue of chameleons. Our results thus suggest that albanerpetontids were sit-and-wait ballistic tongue feeders, extending the record of this specialized feeding mode by around 100 million years.
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David B. Wake (2020)
A surprising fossil vertebrate.
Science 370(6517): 654-655
DOI: 10.1126/science.abe7826
https://science.sciencemag.org/content/370/6517/654Summary
The invasion of land by vertebrates initiated an explosion of new kinds of organisms--amphibians--whose diversity ballooned until the extinction event that ended the Paleozoic Era 252 million years ago (Ma) nearly wiped them out. Several early amphibians became specialized in morphology and life history, even including forms that lost limbs. Many had bizarre shapes, and they also varied greatly in size. Among them were the ancestors of the still-living salamanders, frogs, and caecilians, collectively known as lissamphibians. By the dawn of the Mesozoic Era, which followed the Paleozoic, only lissamphibians and one other group (trematosaurs) survived. The last trematosaurs disappeared in the late Mesozoic, 120 Ma. But paleontologists had overlooked one clade. On page 687 of this issue, Daza et al. (1) introduce an unusual fossil of the obscure and apparently extinct albanerpetontids.
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