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© β01γ International Society of Zoological Sciences, Institute of Zoology/
Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd
Integrative Zoology 2014; 9: 121–140 doi: 10.1111/1749-4877.12052
ORIGINAL ARTICLE
Early–Middle Ordovician brachiopod dispersal patterns in South
China
Renbin ZHAN
1
and Jisuo JIN
2
1
State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of
Sciences, Nanjing, China and
2
Department of Earth Sciences, Western University, London, Ontario, Canada
Abstract
Paleobiogeographic patterns of the brachiopod faunas before and during the irst radiation of the Great Ordovi-
cian Biodiversiication Event (GOBE) in South China at 6 different localities from the upper Jiangnan Slope to
the vast area of the Upper Yangtze Platform show several interesting features. First, the initial brachiopod diver-
sity acme was accompanied by both high origination and extinction rates. Second, no signiicant changes took
place in the taxonomic composition and paleobiogeographic pattern of the brachiopod fauna during the radia-
tion at 5 of the 6 localities studied except the near shore locality, where the irst brachiopod radiation was much
later than at other localities and was marked by a dramatic increase in endemic constituents. Third, orthides
were the predominant brachiopod group during the radiation, and regional brachiopod taxa played a signiicant
role in deining the paleobiogeographic pattern of the radiation. Fourth, the irst brachiopod radiation was asso-
ciated with γ major pulses of onshore migration from the upper Jiangnan Slope through the central Upper Yang-
tze Platform to the near shore settings of the platform, with the middle pulse being the most signiicant. Finally,
paleogeographic dispersal took place in both onshore and offshore directions, although the onshore expansion
was more prominent; several key brachiopods, such as Paralenorthis, Nocturnellia, Protoskenidioides, Nere-
idella, Euorthisina and Yangtzeella, irst appeared on the upper Jiangnan Slope and later formed distinct, and
taxonomically diverse, communities on the Upper Yangtze Platform. The paleogeographic dispersal of brachio-
pods is considered to be closely related to the tectonic evolution of the Qianzhong Arch.
Key words: biotic radiation, brachiopod fauna, China, Ordovician, paleogeography
Correspondence: Renbin Zhan, State Key Laboratory of
Palaeobiology and Stratigraphy, Nanjing Institute of Geology
and Palaeontology, Chinese Academy of Sciences, Nanjing
β10008, China.
Email: rbzhan@nigpas.ac.cn
INTRODUCTION
The Great Ordovician Biodiversification Event
(GOBE) has been intensively investigated in South Chi-
na since β000, in conjunction with the IGCP projects
410 (1997–β00β), 50γ (β004–β009) and 591 (β011–
β015). This has involved systematic studies of more
than 40 Ordovician sections in South China, ranging
from the Upper and the Lower Yangtze Platform to the
Jiangnan Slope, and a series of case studies of various
taxonomic groups. Six classical Lower to Middle Ordo-
vician sections were carefully measured and intensive-
ly collected mainly on the Upper Yangtze Platform (Fig.
1). Taxonomic revisions and faunal analyses on the fos-