Comment on: The ichnogenus Lumbricaria Münster from the Upper Jurassic of Germany interpreted as faecal strings of ammonites

KIETZMANN, DIEGO A.; BRESSAN, GRACIELA S.

Papers in Palaeontology

Blackwell Publishing Ltd

Lugar: Hoboken; Año: 2021

IN their contribution, Knaust & Hoffmann (2021) discussedthe interpretation of the genus Lumbricaria usingseveral specimens from different collections. Lumbricariais a coprolite first described by M?unster (in Goldfuss1831) from the Upper Jurassic lithographic limestonesof Germany. It is characterized by a contorted, wormlikeform of calcitic composition. Until now, for all theknown records of the accepted ichnospecies of Lumbricaria(L. intestinum and L. colon), these remains consist3 of saccocomid ossicles. Various origins and producershave been attributed to Lumbricaria (see Janicke 1970).4 So far specimens that undoubtedly fulfil this definitionhave been reported only from Germany, where theywere attributed to ammonite faeces (e.g. Janicke 1970;Schweigert 2001) and Argentina, where various lines ofevidence point to a possible holothuroid producer(Kietzmann & Bressan 2019). On the other hand, Haude(2019) reported a coprolite composed of holothuriansclerites from the Early Jurassic of Germany, which wasincluded as Lumbricaria by Knaust & Hoffmann (2021).Haude (2019) interpreted these coprolites as havingbeen produced by a worm-like predator.We acknowledge that the data presented by Knaust &Hoffmann (2021) are important for the interpretation ofthe producer of this coprolite, and particularly those fromGermany. When comparing with the material fromArgentina, however, the authors misreported our paper.The aim of this comment is to correct some of the reinterpretationsmade by Knaust & Hoffmann (2021)...