کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
6448369 | 1642085 | 2012 | 8 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
A large halecomorph fish (Actinopterygii: Holostei) from the Valanginian (Early Cretaceous) of southeast France
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موضوعات مرتبط
مهندسی و علوم پایه
علوم زمین و سیارات
فسیل شناسی
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چکیده انگلیسی
A new species of the halecomorph fish â Tomognathus, â T. gigeri, is described on the basis of an isolated piece of a snout found in the Valanginian in the vicinity of Toulon, southeast France. Although very fragmentary, the specimen shows several of the very specialized characters of â Tomognathus, such as fused premaxillae with a posterior ventral process that sutures with an unpaired vomer, a blunt stout, a compound ethmoid ossification with no distinct lateral ethmoid and pre-ethmoid, as well as large, hollow teeth with a thin wall. Several characters, however, clearly indicate that the specimen represents a new species, which is 40 million years older than the type species (Valanginian and Cenomanian respectively). â Tomognathus had a debated systematic status for more than a century, and its placement within the halecomorphs is recent. Characters of the new species confirm this assignment, in particular the carinate shape of the acrodine tips of its teeth, which differs from those of the type species, but is similar to the teeth of the halecomorph superfamily Caturoidea.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Cretaceous Research - Volume 37, October 2012, Pages 201-208
Journal: Cretaceous Research - Volume 37, October 2012, Pages 201-208
نویسندگان
Lionel Cavin, Stephen Giner,