Vertebrate Palaeontology Laboratory, Life and Planetary Evolution Research Group, Department of Earth Sciences, The University of Hong Kong , Pokfulam, Hong Kong , China.
Key Laboratory of Vertebrate Evolution and Human Origin of Chinese Academy of Sciences, Institute of Vertebrate Paleontology & Paleoanthropology, Chinese Academy of Sciences , Beijing , China.
PeerJ. 2015 Mar 26;3:e865. doi: 10.7717/peerj.865. eCollection 2015.
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.
我们基于从中国香港鲤鱼门组火山碎屑泥岩中采集的后躯骨骼，描述了一种中生代鱼类 Paralycoptera sp.（硬骨鱼纲：骨舌鱼目）。这一新发现代表了该市的首例中生代鱼类，将 Paralycoptera 的地理分布范围从中国大陆东部扩展到香港，表明该属的分布范围比以前认为的要广。鲤鱼门组的放射性测年结果为 146.6±0.2 Ma，这意味着 Paralycoptera 的时间范围扩展了大约 4000 万年，回到了早白垩世（约 1.1 亿年前）。然而，在该组中发现的孢子表明其年代为早白垩世，与现有的 Paralycoptera 年代分配一致。我们认为，所提出的时间范围扩展是真实的，因为它基于最近的高精度放射性测年数据，但鉴于与生物地层年代的差异，需要进一步调查来证实这一点。本研究为揭示香港中生代脊椎动物群及其与中国内地研究充分的脊椎动物群的关系提供了重要的一步。
