Biodiv Sci ›› 2001, Vol. 09 ›› Issue (4): 336-344.  DOI: 10.17520/biods.2001050

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Fish fauna and zoogeographical analysis of Shi Wan Da Shan Mountains, Guangxi, China

ZHAO Ya-Hui, ZHANG Chun-Guang   

  1. Institute of Zoology , Chinese Academy of Sciences , Beijing 100080
  • Received:2001-03-20 Revised:2001-09-11 Online:2001-11-20 Published:2001-11-20
  • Contact: ZHAO YaHui

Abstract: The Shi Wan Da Shan Mountains (literally“a hundred thousand gigantic mountains”) are located in the southwestern part of the Guangxi Zhuang Autonomous Region , China. The st reams on the northern side of the Shi Wan Da Shan Mountains are mainly the upst ream tributaries of the southern side of the Mingjiang River basin , belonging to the Pearl River system. There are many substantive river st reams on the southern side and the st reams are near to each other but discharge independently into the Beibu Gulf . Due to the complicated geographical conditions in the Shi Wan Da Shan Mountains , the species diversity of fish is very abundant . We collected 84 species and subspecies in the area during the spring of 1998 and the fall of 1999 , and another 18 species and subspecies were recorded in past references.Altogether 102 species and subspecies are found in the Shi Wan Da Shan Mountains. All the fish belong to six orders , 18 families and 65 genera. Among them , 97 species and subspecies are pure f reshwater fishes , belonging to four orders , 16 families and 61 genera. There are 63 species and subspecies in Cypriniformes which account for 64. 95 % of the total f reshwater fish in the area ; 18 species belong to Perciformes which account for 18. 56 %of the total , 15 species are in the Siluriformes which account for 15. 46 % of the total , one species in the Synbranchiformes which accounts for 1. 03 % of the total.Apparently , Cypriniformes constitute the main component of the fish fauna in the Shi Wan Da Shan Mountains. The analysis of average faunal resemblance (AFR) among the different river systems indicates that great differences of the fish fauna exist between the southern side and northern side. Sixty species and subspecies are dist ributed on the northern side , and 78 species and subspecies are on the south side , 40 species and subspecies are shared on both sides , and the AFR between both sides is 59. 6 %.Comparing the fish of the south side to the fish on Hainan Island sixty species and subspecies are shared and the AFR between areas is 67. 8 %. The above analyses indicate that the fish fauna of the south side of the Shi Wan Da Shan Mountains has a much closer relationship to the fish fauna of Hainan Island than to the north side of the same mountains. It is suggested that the similarity of fish fauna between the south side of the Shi Wan Da Shan Mountians and Hainan Island is related to the change of environment during the Quaternary Ice Age. According to the literature , the level of sea descended about 150 meters during that period and the Beibu Gulf might have been a low continental bridge allowing the fishfauna between the two sides to exchang with each other. Regionally , the whole fish fauna of the Shi Wan Da Shan Mountains belongs to the South China Region (SCR) of the great Oritental Region , but the fish fauna of the south side belongs to the Hainan Subregion of SCR and the fish fauna of the northern side belongs to the Pearl River Subregion (SCR) .