Remarkable teleostean fishes from the Late Jurassic of southern Germany and their phylogenetic relationships
Bibliographic record
Abstract
Complete descriptions, as preservation permits, are provided for new Late Jurassic taxa (e.g., †<i>Ascalabothrissops voelkli</i> n. gen. and n. sp., †<i>Anaethalion zapporum</i> n. sp., and †<i>Elopsomolos frickhingeri</i> n. gen. and n. sp.); the phylogenetic positions of these taxa are given, as well as an evaluation of the European teleosts during the Late Jurassic. <br><br> The relationships among certain fossil and extant teleosts are evaluated based on 191 unweighted morphological characters by using cladistic principles. The results suggest that †<i>Ascalabothrissops</i> n. gen. from the Kimmeridgian of Schamhaupten is the sister-taxon of †<i>Pachythrissops</i> from the Tithonian of Bavaria, and consequently is an ichthyodectiform. †<i>Anaethalion zapporum</i> n. sp., an elopiform, stands in an unresolved polytomy with †<i>A. angustus, †A. knorri</i>, and a clade formed by †<i>A. angustissimus</i> and more advanced elopiforms. The new results confirm Arratia (1997) that †<i>Anaethalion</i>, as presently understood, is a paraphyletic taxon. †<i>Elopsomolos frickhingeri</i> n. gen. and n. sp. forms a polytomy with †<i>Elopsomolos</i> sp. 1 and 3, and [<i>Elops + Megalops</i>]. Monophyly of the Kimmeridgian and Tithonian genus †<i>Elopsomolos</i> is not certain. <br><br> Following the new phylogenetic hypothesis, that includes new taxa and new characters, the elopomorphs stand as the primitive sister-group of osteoglossomorphs and more advanced teleosts. The new information does not affect the phylogenetic position of the main extant teleostean clades and confirms previous results by Arratia (1991, 1996, 1997, 1999). <br><br> The analysis of the elopiforms through time shows that the group had an important radiation during the Late Jurassic, to be replaced by new genera and species during the Cretaceous, and again during the Cenozoic. From numerous genera living in the past, elopiforms are represented now by two genera, <i>Elops</i> and <i>Megalops</i>. <br><br> Soweit es die Erhaltung zulässt, werden vollständige Beschreibungen der drei neuen spätjurassischen Taxa †<i>Ascalabothrissops voelkli</i> n. gen. et n. sp., †<i>Anaethalion zapporum</i> n. sp., und †<i>Elopsomolos frickhingeri</i> n. gen. et n. sp. gegeben. Die phylogenetische Stellung dieser Taxa als auch anderer spätjurassischer europäischer Teleosteer ist analysiert. <br><br> Die Verwandtschaftsbeziehungen innerhalb einiger fossiler und rezenter Teleosteer wurden auf der Basis von 191 nicht gewichteten morphologischen Merkmalen mit Hilfe der kladistischen Methode evaluiert. Als Ergebnis zeigt sich, dass †<i>Ascalabothrissops</i> n. gen. aus dem Kimmeridgium von Schamhaupten das Schwestertaxon von †<i>Pachythrissops</i> und damit ein Ichthyodectiformer ist. †<i>Anaethalion zapporum</i> n. sp., ein Elopiformer, steht in einer nicht auflösbaren Polytomie mit †<i>A. angustus, †A, knorri</i>, und einer Gruppe gebildet aus †<i>A. angustissimus</i> und weiter fortgeschrittenen Elopiformen. Die neuen Ergebnisse bestätigen Arratia (1997), dass †<i>Anaethalion</i>, wie zur Zeit umgrenzt, ein paraphylethisches Taxon darstellt. †<i>Elopsomolos frickhingeri</i> n. gen. et n. sp. bildet eine Polytomie mit †<i>Elopsomolos</i> sp. 1 und 3, und [<i>Elops + Megalops</i>]. Die Monophylie der Gattung †<i>Elopsomolos</i> aus dem Kimmeridgium und Tithonium ist nicht gesichert. <br><br> Nach der neuen phylogenetischen Hypothese, die neue Taxa und neue Merkmale einbezieht, sind die Elopomorphen die primitive Schwestergruppe der Osteoglossomorphen und weiter fortgeschrittener Teleosteer. Die neuen Ergebnisse beeinflussen die phylogenetische Stellung der rezenten Hauptgruppen der Teleosteer nicht und bestätigen frühere Ergebnisse von Arratia (1991, 1996, 1997, 1999). <br><br> Die Analyse der Elopiformen zeigt, dass die Gruppe eine bedeutende Radiation im Spätjura erlebte; neue Gattungen und Arten traten in der Kreide auf und dann wieder im Känozoikum. Im Gegensatz zu den zahlreichen fossilen Gattungen sind die Elopiformen heute nur durch zwei Gattungen vertreten, <i>Elops</i> und <i>Megalops</i>. <br><br> doi:<a href="http://dx.doi.org/10.1002/mmng.20000030108" target="_blank">10.1002/mmng.20000030108</a>
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.003 | 0.003 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.005 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".