Phylogenetic inference of Priacanthidae from morphometric studies

Abstract

Phylogenetic relationship of eight different species of priacanthids around Taiwan were studied via morphometric measurements. These species are Pristigenys multifasciatus, P. niphonia, Cookeolus boops, Priacanthus cruentatus, P. tayenus, P. macracanthus, P. hamrur, and P. blochii. A total of twenty-three individuals (OTUs), two to seven individuals for each species, were analyzed simultaneously to evaluate various numerical taxonomic techniques in regard to the criterion that conspecific taxa should be clustered near each other. It is shown that the measurements of truss method tend to give better results compared to that of using traditional methods. Among phenetic methods, Bray-Curtis dissimilarity coefficient performs the best among a total of seven resemblance coefficients under test, and UPGMA gives better phenograms than the other three clustering methods. For cladistic analysis Wagner distance using the parsimony principle and Fitch-Margoliash method were applied to construct cladograms which, in general, agree with the geneological relationship of priacanthids inferred from various phenetic classifications. The phylogeny of Priacanthidae contains three convex groups which are exactly in correspondence to three different genera. Pristigenys multifasciatus and P. niphonia are grouped with each other. Cookeolus boops in intermediate between both genera of Pristogenys and Priacanthus. Within the genus of Priacanthus, P. tayenus is the one which is more related to C. boops than the other four congeneric species. P. brochii and P. harmur are sister groups but their relationship with P. macracanthus and P. cruentatus is not clear. This paper also gives a demonstration of how to use morphometric data to infer the fish phylogeny.