The macrosemiiform fish companion of the Late Jurassic theropod Juravenator from Schamhaupten, Bavaria, Germany

Abstract

A new neopterygian fish, Voelklichthys comitatus n. gen. n. sp., is described. The fish was found during the preparation of the theropod Juravenator starki in the same rock. The fish possesses numerous autapomorphies. The combination of autapomorphies is unique among Jurassic fishes and makes its taxonomic assignment difficult. The following characters are few examples demonstrating some of the peculiarities of the fish: The fish is small, oblong-shaped and has a large triangular head that is deeper than long; deepest point is at the level of the postparietal bone [parietal of traditional terminology] and the ventral end of the cleithrum. The skull roof is almost vertically oriented, with a strongly ossified and developed anterodorsal orbital margin. Premaxilla and dentary possess very small conical teeth. The opercular apparatus is markedly narrow and deep. A clavicle is present. Both dorsal and ventral postcleithra are almost as deep as the maximum depth of the head; the dorsal postcleithrum is two times deeper than the ventral one. The vertebral centra are of arcocentral-type formed mainly by the development of the dorsal arcocentra. Pectoral and pelvic fins possess long rays that extend onto the pelvic and anal fins, respectively, whereas the rays of the dorsal and anal fins extend onto the caudal fin. The fish is interpreted as a macrosemiiform because it presents two of the three synapomorphies of the group (e.g., an incomplete circumorbital ring because the lateral edge of parietal bone [frontal of traditional terminology] makes up part of orbital margin and absence of a supramaxillary bone). The third macrosemiiform synapomorphy cannot be determined in the new fish because the coronoid bones and their dentition are not observed due to condition of preservation. The new fish shares a few characters with members of the families Macrosemiidae and the Uarbryichthyidae but lacks others so that presently, we place it in a family indeterminate within Macrosemiiformes. ). This small reptile "is one of the most complete non-avian theropod skeletons described to date for Europe, and a significant addition to the scant worldwide record of small-bodied Late Jurassic theropods" (Chiappe & Gaehlich 2010, p. 291).During the preparation of Juravenator starki, Mr. Vaelkl found a small fish among the discarded rock pieces, which he checked one by one, but he did not find any other fossil. The fish appeared to be something very unusual for someone like him familiar with the preparation of fishes of the Solnhofen limestones. He prepared the small specimen and presented it to G. Arratia during one of her frequent visits of the JuraMuseum Eichstått.Numerous fossils showing a broad diversity were recovered during the scientific excavations in Schamhaupten. These include plants, microfossils, sponges, corals, gastropods, bivalves, cephalopods, bryozoans, brachiopods, polychaetes, arthropods, echinoderms, fishes, marine reptiles, and Juravenator as single terrestrial reptile (Viohl & Zapp 2006). The fishes represent the...

Diversity of vertebrate remains from the Lower Gogolin Beds (Anisian) of southern Poland

“…Morphotype 1 has distinct vertices, a serration on one of the edges, and stair-like notches on the internal surface (Fig. 4A) similar to scales of macrosemiidae (Arratia and Schultze, 2012). Morphotype 2 is smooth with growth structures (similar to growth rings of cycloid scales) visible on the external surfaces (Fig.…”

Scale morphology and specialized dorsal scales of a new teleosteomorph fish from the Aptian of West Gondwana

“…However, these structures are common among holosteans, such as Semionotiformes, Lepisosteiformes (Bürgin, 2004;Lombardo and Tintori, 2008;Grande, 2010;Cavin et al, 2013), and Macrosemiiformes (Schultze, 1966;Bartram, 1977;Bravi, 1994;González-Rodríguez and Reynoso, 2004;González-Rodríguez et al, 2004;Arratia and Schultze, 2012). In this character, Teleosteomorpha n. sp.…”

“…There are amioid scales in the gular region of some species of macrosemiiforms and, furthermore, there are ganoid scales on the flanks of the same individual (e.g., Macrosemius rostratus, Propterus microstomus, and Notagogus denticulatus; Schultze, 1966;Bartram, 1977;Arratia and Schultze, 2012).…”

A New Large †Pachycormiform (Teleosteomorpha: †Pachycormiformes) from the Lower Jurassic of Germany, with Affinities to the Suspension-Feeding Clade, and Comments on the Gastrointestinal Anatomy of Pachycormid Fishes

“…Early works lumped material from Diversity 2022, 14, 1026 2 of 42 numerous localities and ages into these poorly diagnosed genera, broadening taxonomic diagnoses and stratigraphic ranges [7][8][9][10]. Many museum curators followed this flawed taxonomy, especially for Early Jurassic (Toarcian) materials based on taxa said to be present in Hauff and Hauff's [11] Das Holzmadenbuch [12][13][14][15]. A recent renaissance of interest in pachycormid research over the last few decades has made progressive steps toward resolving some of these issues, with many historic genera now better defined and several new taxa formally described [5,6,[13][14][15][16][17].…”

“…Many museum curators followed this flawed taxonomy, especially for Early Jurassic (Toarcian) materials based on taxa said to be present in Hauff and Hauff's [11] Das Holzmadenbuch [12][13][14][15]. A recent renaissance of interest in pachycormid research over the last few decades has made progressive steps toward resolving some of these issues, with many historic genera now better defined and several new taxa formally described [5,6,[13][14][15][16][17]. Nonetheless, the majority of these studies have focused on stratigraphically younger pachycormids, ranging from the Middle Jurassic to Late Cretaceous [5,6,[13][14][15][17][18][19][20][21], with little research attention directed towards Early Jurassic taxa [1,[22][23][24].…”