Article: Reconstruction of an apparatus of Neostrachanognathus tahoensis from Oritate, Japan and species of Neostrachanognathus from Oman

The apparatus of an Early Triassic conodont Neostrachanognathus tahoensisKoike, 1998 from Oritate, Kumamoto Prefecture, Japan, and a species of Neostrachanognathus from Oman were reconstructed. On the basis of five natural assemblages from the Oritate area, the three-dimensional apparatus model of N. tahoensis is interpreted as bilaterally symmetrical and composed of 14 elements consisting of pairs of P1, P2, P3, S1, S2, S3, and S4 elements. The P1 and P2 elements are coniform elements, the P3 elements are digyrate forms, and the S elements are bipennate ramiforms. The S elements are arranged rostrally in the apparatus and the pairs of the P1, P2, and P3 elements are subvertically arranged caudally and ventrally to the S array. One of the natural assemblages was formed by rostrocaudal collapse of the apparatus on the sea floor, whereas the other assemblages indicate that conodont animals came to rest nearly parallel with the substrate prior to burial. A collection of isolated elements from Jabal Safra, Oman, includes a second species of Neostrachanognathus with a comparable apparatus. KEYWORDS Apparatus • conodont • Japan • natural assemblage • Oman • Triassic