A new look at the Cretaceous Lamprey Mesomyzon Chang, Zhang & Miao, 2006 from the Jehol Biota
نویسندگان
چکیده
Lampreys, one of the remaining two living jawless vertebrates, carry great weight in study vertebrate evolution. They have a long history dating back to Devonian but left scarce fossil record. So far, only five unequivocal lampreys been described, which four are Paleozoic. Mesomyzon Chang, Zhang & Miao, 2006, known Mesozoic lamprey bridging Paleozoic and extant relatives, was originally considered similar morphology life modern forms. Although being repeatedly referred early phylogeny, is far from adequately known. Based on extensive investigations numerous new well-preserved specimens, we present herein more details this lamprey, thereby releasing package information cranial nerves, some associated structures oral disc, naso-hypophysial complex, barely preserved previously lampreys. shows peculiarities having an extremely anterior dorsal fin ribbon-like preanal skin fold, hence restored distinct profile formerly claimed look. Additionally, it shares with Southern Hemispheric species widely separated fins, posteriorly positioned cloaca enlarged papillae. In light these data, feeding ecology tentatively discussed likely blood feeder, judging reinforcement attachment sensory periphery disc.
منابع مشابه
Under Cover at Pre-Angiosperm Times: A Cloaked Phasmatodean Insect from the Early Cretaceous Jehol Biota
BACKGROUND Fossil species that can be conclusively identified as stem-relatives of stick- and leaf-insects (Phasmatodea) are extremely rare, especially for the Mesozoic era. This dearth in the paleontological record makes assessments on the origin and age of the group problematic and impedes investigations of evolutionary key aspects, such as wing development, sexual size dimorphism and plant m...
متن کاملNew basal eutherian mammal from the Early Cretaceous Jehol biota, Liaoning, China.
A new genus and species of eutherian mammal, Acristatherium yanensis gen. et sp. nov., is described from the Early Cretaceous Jehol biota, China. The new taxon is based on a partial skull that is preserved in three dimensions from the Lujiatun bed of the Yixian Formation and dated 123.2+/-1.0 Ma. Its right upper and lower dentitions are nearly complete and it has a dental formula 4.1.5.3/3.1.5....
متن کاملThe first juvenile specimen of Manchurochelys manchoukuoensis from the Early Cretaceous Jehol Biota
A small juvenile turtle is described from the Early Cretaceous Jehol Biota, shedding light on the juvenile morphology and ontogeny of Manchurochelys manchoukuoensis. Several juvenile features are uncovered, such as a small and circular carapace (less than half of the adult), wide vertebral scales, and lateral carapacial fontanelles. In contrast to the adult morphology, which has an oval carapac...
متن کاملRods and cones in an enantiornithine bird eye from the Early Cretaceous Jehol Biota
Extant birds have an extensive spectral range of colour vision among vertebrates, but evidence of colour vision among extinct birds has hitherto been lacking. An exceptionally well-preserved extinct enantiornithine fossil bird from the Early Cretaceous Jiufotang Formation (120 Ma) of Liaoning, China, provides the first report of mineralised soft tissue of a bird eye. Cone cells are identified, ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Geodiversitas
سال: 2021
ISSN: ['1638-9395', '1280-9659']
DOI: https://doi.org/10.5252/geodiversitas2021v43a23