Evolutionary analyses of phylum Chaetognatha based on mitochondrial cytochrome oxidase I gene

Turkish journal of zoology

article

SAM PETER¹  MANOJKUMAR BHASKARAN NAIR³  DEVIKA PILLAI² 

[1] School of Ocean Studies and Technology, Kerala University of Fisheries and Ocean Studies;Department of Aquatic Animal Health Management, Kerala University of Fisheries and Ocean Studies;School of Fisheries Resource Management, Kerala University of Fisheries and Ocean Studies

关键词: Chaetognatha;    evolution;    phylogenetic analysis;    mitochondrial cytochrome oxidase I gene;    Bayesian inference;    maximum likelihood;   

DOI  :  10.3906/zoo-2004-18

学科分类：生物科学（综合）

来源: Scientific and Technical Research Council of Turkey - TUBITAK

【 摘 要 】

Chaetognaths (arrow worms) are an enigmatic group of transparent planktonic invertebrates and play an important role in the marine food web. Their morphological and developmental features have raised extensive debates since the discovery of the phylum in the 18th century. Uncertainty in the phylogenetic placement of certain chaetognath species still exists and is puzzling many scientists who have tried to clarify this task. Studies using a portion of both small subunit ribosomal ribonucleic acid (SSU rRNA) and large subunit ribosomal ribonucleic acid (LSU rRNA) genes when integrated with conventional taxonomy were contributed to resolve taxonomical issues in this group. Here we present the first phylogenetic study of Chaetognatha based on a portion of mitochondrial cytochrome oxidase I (COI) gene and compare our results with the earlier morphological and molecular evolutionary hypotheses. This study includes 16 extant species, representing 8 genera and 6 of which are among the 9 extant families. We recommend the following clade structure for the phylum: Aphragmophora comprising Sagittidae with Pterosagittidae and Krohnittidae included in the Sagittidae and Phragmophora comprising Eukrohniidae, Spadellidae, and Heterokrohniidae. Phylogenetic analyses also supported the division of Phragmophora into two monophyletic groups: the Monophragmophora and Biphragmophora. Moreover, Ctenodontina/ Flabellodontina and Syngonata/Chorismogonata suborders were not validated. Precise phylogenetic investigations using various molecular markers and specimens from diverse regions are definitely needed to provide an exact evolutionary concept on this phylum.

【 授权许可】

Unknown