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.

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ژورنال

عنوان ژورنال: Geodiversitas

سال: 2021

ISSN: ['1638-9395', '1280-9659']

DOI: https://doi.org/10.5252/geodiversitas2021v43a23