Turbellarian taxonomic database

Abstract / Notes

Table of size and nos. of chromosomes including all known determinations in Turbellaria. The size varies
inversely with the number. The chromosomes of the Microstomidae resemble those of the Catenulidae more than
they do those of the Macrostomidae, so that the 1st and 3d families seem not as closely related as usually
supposed. The members of 1 genus usually have the same chromosome number but exceptions occur in
Macrostomum,
Paravortex, Mesostoma, Dendrocoelum, and Planaria (sensu lato). In 11 ssp. of Dalyellia, 2n=4. The 2 genera
Polycystis and Acrorhynchus, belonging to the same family, diverge widely as regards chromosome number. The
rhabdocoele groups Typhloplanoida and Kalyptorhynchia appear closely related. The few Alloeocoela for which
data are available diverge considerably. Similarities in chromosome number occur between triclads and
polyclads. The small size of the chromosomes of Temnocephala may indicate some affinity to the Dalyelliidae. 

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