Revision of Cyprinus maomingensis Liu 1957 and the first discovery of Procypris-like cyprinid (Teleostei, Pisces) from the late Eocene of South China

Fossil cyprinids from the upper part of the upper Eocene Youganwo Formation of Maoming, Guangdong, China were first studied in 1957 by Liu, who referred the only specimen to the genus Cyprinus as a new species, C. maomingensis. And this was suggested as one of the earliest records for fossil cyprinids. Unfortunately, this specimen is poorly preserved and reveals no more morphological information than its serrated last unbranched dorsal and anal fin rays. Recently, some new specimens were unearthed from the same locality, where C. maomingensis was discovered. In addition to the serrated dorsal and anal fin rays, these new materials also show that the pattern and shape of their pharyngeal teeth obviously differ from that of Cyprinus but resemble that of Procypris. However, its number of the branched dorsal fin rays and number of vertebrae are much less than that in Procypris. Morphologically, these specimens are closer to Procypris than to Cyprinus. This is the first report of fossil Procypris-like fish, and it implies that Procypris-like fish is an early member of the Tribe Cyprinini sensu stricto (sensu Yang et al., 2010) and the origin of this group can be traced back at least to the late Eocene

<i>Diabolepis</i> et sa signification quant aux relations de parenté entre les Porolépiformes et les Dipneustes

Cette étude révèle de nouveaux caractères morphologiques de Diabolepis, sur la base de nouveaux spécimens et la préparation d&#39;ancien matériel. Les caractères crâniens sont énumérés et analysés de manière à fournir une base à la discussion des relations de parenté de Diabolepis. Le crâne de Diabolepis présente nombre de caractères primitifs de Sarcoptérygiens, qui sont à l&#39;origine de l&#39;hésitation à placer Diabolepis parmi les Dipneustes. Chez Diabolepis, les plaques ptérygoïdiennes et la amandibule présentent plus de caractères de Dipneustes que le crâne. Bien que ces caractères des plaques ptérygoïdiennes et de la mandibule soient typiques des Dipneustes, l&#39;incertitude sur leur appartenance au même animal était la principale raison pour ne pas reconnaître Diabolepis comme un Dipneuste. Cette étude confirme que le crâne, les mandibules et les ptérygoïdes appartiennent à la même forme. Par exemple, les processus du bord mésial de la face dorsale du palatocarré correspondent bien aux fosses de la face ventrale de l&#39;endocrâne. Ceci est corroboré par une disposition similaire des os dermiques, la morphologie dentaire et les surfaces d&#39;usure sur le palais et la face linguale de la mandibule. Ces caractères, ainsi que d&#39;autres, qui sont uniques aux Dipneustes renforcent l&#39;hypothèse d&#39;une relation étroite entre Diabolepis et ce groupe. La signification de Diabolepis et sa portée quant à la relation entre les Dipneustes et les Porolépiformes (incluant Powichthys et Youngolepis) sont discutées.This study reveals new morphological features of Diabolepis based on new specimens and further preparation of previously available materials. Cranial characters are summarized and analyzed in order to provide a basis for discussing the relationships of Diabolepis. The cranium of Diabolepis shows a number of primitive sarcopterygian characters. Previous hesitation in placing Diabolepis in the Dipnoi mainly arose from these primitive sarcopterygian features. In Diabolepis, the pterygoid plate and lower jaw bear more dipnoan characters than the cranium. Although these features in the pterygoid plate and lower jaw are typical of the dipnoan condition, uncertainty as to whether the lower jaw, pterygoids and cranium belong to the same animal was used as the main reason for not accepting Diabolepis as a dipnoan. The present study reveals further evidence that the lower jaw, pterygoids and the cranium belong to the same form. For example, the processes along the median margin of the dorsal surface of the palatoquadrate fit well into the corresponding fossae on the ventral side of the neurocranium. This is corroborated by similar disposition of dermal bones, tooth morphology and wear patterns shown on the palate and lingual face of the lower jaw. These and other uniquely shared features lend further support to a close relationship between Diabolepis and dipnoans. The significance of the Diabolepis and its bearing on the close relationship between dipnoans and porolepiforms (including Powichthys and Youngolepis) are further discussed.</p

Guiclupea superstes, gen. et sp. nov., the youngest ellimmichthyiform (clupeomorph) fish to date from the Oligocene of South China

A new ellimmichthyiform, Guiclupea superstes, gen. et sp. nov., from the Oligocene Ningming Formation of Ningming Basin, Guangxi Zhuang Autonomous Region, South China is described herein. With relatively large body size, parietals meeting at the midline, anterior ceratohyal with a beryciform foramen in the center, a complete predorsal scutes series of very high number and about equally-size scutes with radiating ridges on dorsal surface, first preural centrum unfused with first uroneural but fused with the parhypural, and first ural centrum of roughly the same size as the preural centrum, Guiclupea superstes cannot be assigned to the order Clupeiformes. The phylogenetic analyses using parsimony and Bayesian inference methods with Chanos/Elops as outgroup respectively suggests that the new form is closer to ellimmichthyiform genus Diplomystus than to any other fishes, although there are some discrepancies between the two criteria and different outgroups used. It shares with Diplomystus the high supraoccipital crest, pelvic-fin insertion in advance of dorsal fin origin, and the number of predorsal scutes more than 20. The new form represents the youngest ellimmichthyiform fish record in the world. Its discovery indicates that the members of the Ellimmichthyiformes had a wider distribution range and a longer evolutional history than previously known

A specimen of Paralycoptera Chang & Chou 1977 (Teleostei: Osteoglossoidei) from Hong Kong (China) with a potential Late Jurassic age that extends the temporal and geographical range of the genus

We describe a Mesozoic fish Paralycoptera sp. (Teleostei: Osteoglossoidei), on the basis of a postcranial skeleton collected from the volcaniclastic mudstones of the Lai Chi Chong Formation of Hong Kong, China. The new finding—representing the city’s first Mesozoic fish—extends the geographical distribution of Paralycoptera from eastern mainland China into Hong Kong, demonstrating a wider distribution than previously appreciated for this genus. A radiometric age for the Lai Chi Chong Formation of 146.6 ± 0.2 Ma implies a temporal range expansion for Paralycoptera of approximately 40 million years back from the Early Cretaceous (∼110 Ma). However, spores found in the Formation suggest an Early Cretaceous age that is consistent with the existing age assignment to Paralycoptera. We argue that the proposed temporal range extension is genuine because it is based on recent high precision radiometric age data, but given the discrepancies with the biostratigraphic ages further investigation is needed to confirm this. This study provides an important step towards revealing Hong Kong’s Mesozoic vertebrate fauna and understanding its relationship to well-studied mainland Chinese ones