Coleoid beaks from the Nusplingen Lithographic Limestone (Upper Kimmeridgian, SW Germany)
Coleoid beaks from the Nusplingen Lithographic Limestone (Upper Kimmeridgian, SW Germany)
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来自努斯普林根平版石灰岩的鞘喙鸟（德国西南部上启默里阶）
DOI：
10.1080/00241160510013303
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发表时间：
2005
期刊：
影响因子：
1.5
通讯作者：
D. Fuchs
中科院分区：
文献类型：
--
作者：
C. Klug;G. Schweigert;G. Dietl;D. Fuchs
在努斯普林根石印石灰岩（德国西南部，上侏罗纪，基梅里吉纪晚期，乌尔芒斯亚带，贝克尔里带）中发现了20多个鞘翅虫喙的标本。根据它们的形态，可以区分出四种形式的下喙和三种形式的上喙。两个gladii的Trachyteuthis hastiformis与一个完整的喙，因此使分类分配的两个喙的形式。在两个标本中的一个，喙仍然铰接。第三个标本在一块板上显示了另一种形式的上下喙，这被初步解释为Plesioteuthis prisca的喙元件。最大类型的上喙可能属于Leptotheuthis基于其稀缺性和大小。其余两种形式是不确定的分类从属关系。Trachyteuthis的下喙类似于现代章鱼，因此表明与腕足动物有密切的系统发育关系，因为Vampyroteuthis的下喙具有不同的形态。这些最初部分为几丁质的结构是在努斯普林根的化石岩中发现的，因为沥青沉积物中仍然含有大量的原始有机物。这可能是由于各地层的低渗透性造成的。否则，如果没有颜色对比，这些微妙的结构将很难在碳酸盐基质中辨别出来。
Over twenty specimens of coleoid beaks were recovered from the Nusplingen Lithographic Limestone (Upper Jurassic, Late Kimmeridgian, Beckeri Zone, Ulmense Subzone; SW Germany). Based on their morphology, four forms of lower beaks and three forms of upper beaks can be distinguished among the finds. Two gladii of Trachyteuthis hastiformis are associated with a complete beak and hence enable taxonomic assignment of two beak forms. In one of the two specimens, the beaks are still articulated. A third specimen shows another form of upper and lower beak on one slab, which is tentatively interpreted as the beak elements of Plesioteuthis prisca. The largest type of upper beak probably belongs to Leptotheuthis based on its scarcity and size. The remaining two forms are of uncertain taxonomic affiliation. The lower beak of Trachyteuthis resembles that of Recent Octopus and thus suggests a close phylogenetic relation to the Octopoda, as the lower beak of Vampyroteuthis has a different morphology. These originally partially chitinous structures were discovered in the Fossillagerstatte of Nusplingen because the bituminous sediments still contain a significant portion of the original organic matter. This might be the case because of a low permeability of the respective strata. Otherwise, without the color contrast, these delicate structures would hardly be discernible against the carbonate matrix.