Dataset Information

Investigation of the validity of species status of Ixodes dammini (Acari: Ixodidae) using rDNA.

ABSTRACT: The two internal transcribed spacers (ITS1 and ITS2) of rDNA of three members of the Ixodes ricinus "complex" (Acari: Ixodidae) were sequenced. Sequence variation was assessed for the North American species I. scapularis, I. dammini, and I. pacificus at three levels: within individual/population, between individuals of different geographic origin within a species, and between species. Both spacers are highly variable, particularly with regard to small deletions and additions which may arise via replication slippage. Homogenization of rDNA multigene arrays for particular sequence variants appears to occur at a relatively rapid rate, since I. pacificus sequences differ from the others at numerous invariant sites, facilitating the use of these sequences to assess sibling species relationships. Based on maximum parsimony and two distance methods (unweighted pair-group with arithmetic means and neighbor-joining), sequence variation in ITS1 and ITS2 suggests that I. scapularis and I. dammini are not distinct species and that even individuals from geographically isolated locations are very similar. Individuals from geographically separated populations of I. pacificus appear to be relatively less closely related to each other but distinct from those of I. scapularis/dammini. In I. scapularis/dammini, diversity within and between individuals from geographic populations contributed equally to total sequence diversity.

SUBMITTER: Wesson DM

PROVIDER: S-EPMC47746 | biostudies-other | 1993 Nov

REPOSITORIES: biostudies-other

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Investigation of the validity of species status of Ixodes dammini (Acari: Ixodidae) using rDNA.

Wesson D M DM McLain D K DK Oliver J H JH Piesman J J Collins F H FH

Proceedings of the National Academy of Sciences of the United States of America 19931101 21

The two internal transcribed spacers (ITS1 and ITS2) of rDNA of three members of the Ixodes ricinus "complex" (Acari: Ixodidae) were sequenced. Sequence variation was assessed for the North American species I. scapularis, I. dammini, and I. pacificus at three levels: within individual/population, between individuals of different geographic origin within a species, and between species. Both spacers are highly variable, particularly with regard to small deletions and additions which may arise via ...[more]

PMID: 8234280

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Dataset Information

Investigation of the validity of species status of Ixodes dammini (Acari: Ixodidae) using rDNA.

Publications

Investigation of the validity of species status of Ixodes dammini (Acari: Ixodidae) using rDNA.

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