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Tse T, Pittman M, Chang M.2014. 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. PeerJ PrePrints2:e725v1https://doi.org/10.7287/peerj.preprints.725v1
We identify an osteoglossoid teleost fish - Paralycoptera - from Late Jurassic volcaniclastic mudstones from the Lai Chi Chong Formation of Hong Kong, China. This partially preserved postcranial skeleton represents the first Mesozoic fish from Hong Kong and the most southerly Paralycoptera to date. A radiometric date for the Lai Chi Chong Formation of ~146 Ma implies a temporal range expansion for Paralycoptera of approximately 40 million years back from the Early Cretaceous (~110Ma). 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 precise and accurate radiometric 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.
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Supplemental tables including phylogenetic data matrices and character lists
Supplemental Tables (S1-S6): S1, Specimens used for comparative studies with SHGM L275; S2-S5, Phylogenetic data matrices and character lists; S6, Spore taxa found in the Lai Chi Chong Formation.
I think you can be reasonably confident of the LCC Fm's age (~146 Ma). Also, the unit is overlain by the Long Harbour Fm, which is dated at about 142 Ma. Actually, you might want to check the basis for the ages of the fish-fossil bearing deposits in Mainland China. They must be dated either directly or indirectly using radiometric ages. I doubt they are better quality than the HK dates because the HK Geol Survey really did go to town in terms of establishing a detailed stratigraphic scheme for the SAR's volcanic succession, and liaised with some of the top labs in the world.