TAXONOMIC STATUS OF THE FISHES OF ACROSSOCHEILUS-FORMOSANUS AND A-LABIATUS (CYPRINIDAE, BARBINAE) FROM TAIWAN BASED ON ISOZYME ELECTROPHORESIS

Taxonomic statuts of the fishes of Acrossocheilus formosanus and A. la biatus (Cyprinidae: Barbinae) from Taiwan based on isozyme electrophor esis. Bull. inst. Zool., Academia Sinica 32(2):127-139. A total of 362 specimens of Acrossocheilus formosanus (AF) and A. labiatus (AL) from five collection sites in Taiwan were analyzed using horizontal starch -gel electrophoresis to clarify their taxonomic status and investigate their genetic variation. A total of 23 loci with 35 alleles were scor ed for 14 enzymes. The short genetic distance between AF and AL (D les s-than-or-equal-to 0.0005) indicates that they are identical species, therefore enabling these two morhpological types to be merged as the s ingle species Acrossocheilus paradox (Steindachner 1892) due to its se niority in the nomenclature. The analyzed samples have genetic distanc es (D) ranging from 0.002-0.046, polymorphic loci (P) from 0.087-0.261 , and mean heterozygosity (HBAR) from 0.005-0.037, indicating that the genetic relationships among them are very close. We offer a possible explanation that the small geographic size of Taiwan and similar water conditions of its rivers may have diminished allozyme variation.