An unusual 100-million-year old holometabolan larva with a piercing mouth cone

PeerJ

article

Joachim T. Haug¹  Mario Schädel¹  Viktor A. Baranov¹  Carolin Haug¹ 

[1] Department of Biology II, Ludwig-Maximilians-Universität München;GeoBio-Center at LMU

关键词: Holometabola;    Insecta;    Evolution;    Mouth parts;    Convergence;   

DOI  :  10.7717/peerj.8661

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Holometabola is a hyperdiverse group characterised by a strong morphological differentiation between early post-embryonic stages (= larvae) and adults. Adult forms of Holometabola, such as wasps, bees, beetles, butterflies, mosquitoes or flies, are strongly differentiated concerning their mouth parts. The larvae most often seem to retain rather plesiomorphic-appearing cutting-grinding mouth parts. Here we report a new unusual larva preserved in Burmese amber. Its mouth parts appear beak-like, forming a distinct piercing mouth cone. Such a morphology is extremely rare among larval forms, restricted to those of some beetles and lacewings. The mouth parts of the new fossil are forward oriented (prognathous). Additionally, the larva has distinct subdivisions of tergites and sternites into several sclerites. Also, the abdomen segments bear prominent protrusions. We discuss this unusual combination of characters in comparison to the many different types of holometabolan larvae. The here reported larva is a new addition to the ‘unusual zoo’ of the Cretaceous fauna including numerous, very unusual appearing forms that have gone extinct at the Cretaceous–Palaeogene boundary.

【 授权许可】

CC BY