New polybranchiaspiform fishes (Agnatha: Galeaspida) from the Middle Palaeozoic of China and their ecomorphological implications Gai, Zhikun ; Lu, Liwu ; Zhao, Wenjin ; Zhu, Min Abstract Publication: PLoS ONE Pub Date: September 2018 DOI: 10.1371/journal.pone.0202217 Bibcode: 2018PLoSO..1302217G