Statistical parsimony networks and species assemblages in Cephalotrichid nemerteans (nemertea).
BACKGROUND
It has been suggested that statistical parsimony network analysis could be used to get an indication of species represented in a set of nucleotide data, and the approach has been used to discuss species boundaries in some taxa.


RESULTS
Based on 635 base pairs of the mitochondrial protein-coding gene cytochrome c oxidase I (COI), we analyzed 152 nemertean specimens using statistical parsimony network analysis with the connection probability set to 95%. The analysis revealed 15 distinct networks together with seven singletons. Statistical parsimony yielded three networks supporting the species status of Cephalothrix rufifrons, C. major and C. spiralis as they currently have been delineated by morphological characters and geographical location. Many other networks contained haplotypes from nearby geographical locations. Cladistic structure by maximum likelihood analysis overall supported the network analysis, but indicated a false positive result where subnetworks should have been connected into one network/species. This probably is caused by undersampling of the intraspecific haplotype diversity.


CONCLUSIONS
Statistical parsimony network analysis provides a rapid and useful tool for detecting possible undescribed/cryptic species among cephalotrichid nemerteans based on COI gene. It should be combined with phylogenetic analysis to get indications of false positive results, i.e., subnetworks that would have been connected with more extensive haplotype sampling.
Chen
Haixia
H
Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, China.
Strand
Malin
M
Norenburg
Jon L
JL
Sun
Shichun
S
Kajihara
Hiroshi
H
Chernyshev
Alexey V
AV
Maslakova
Svetlana A
SA
Sundberg
Per
P
D000818:Animals; D056808:Biostatistics / Q000379:methods*; D003576:Electron Transport Complex IV / Q000235:genetics; D056890:Eukaryota / Q000737:chemistry / Q000145:classification* / Q000201:enzymology / Q000235:genetics*; D006239:Haplotypes; D008969:Molecular Sequence Data; D010802:Phylogeny
D003576:Electron Transport Complex IV