Rose Makae, Harris Jerald D, Milner Andrew R C
Department of Biology, Dixie State University, St. George, UT, USA.
Department of Physical Sciences, Dixie State University, St. George, UT, USA.
PeerJ. 2021 Jan 26;9:e10640. doi: 10.7717/peerj.10640. eCollection 2021.
New invertebrate trace fossils from the Lower Jurassic Moenave Formation at the St. George Dinosaur Discovery Site at Johnson Farm (SGDS) continue to expand the ichnofauna at the site. A previously unstudied arthropod locomotory trace, SGDS 1290, comprises two widely spaced, thick, gently undulating paramedial impressions flanked externally by small, tapered to elongate tracks with a staggered to alternating arrangement. The specimen is not a variant of any existing ichnospecies, but bears a striking resemblance to modern, experimentally generated crayfish walking traces, suggesting a crayfish or crayfish-like maker for the fossil. Because of its uniqueness, we place it in a new ichnospecies, . It is the first fossil crayfish or crayfish-like locomotion trace ever recorded.
来自约翰逊农场圣乔治恐龙发现地（SGDS）下侏罗统莫纳夫组的新型无脊椎动物遗迹化石不断丰富着该地点的遗迹化石群。一种此前未被研究过的节肢动物运动遗迹SGDS 1290，由两条间隔很宽、较粗、微微起伏的中轴旁压痕组成，其外部两侧是小的、逐渐变细至拉长的足迹，呈交错至交替排列。该标本不是任何现有遗迹种的变体，但与现代实验产生的小龙虾行走痕迹惊人地相似，这表明该化石的制造者是小龙虾或类似小龙虾的生物。由于其独特性，我们将其归入一个新的遗迹种。它是有记录以来首个化石小龙虾或类似小龙虾的运动痕迹。
