Chromosome Polymorphism in Archey's Frog (Leiopelma archeyi) from New Zealand
The most primitive frogs in which a sex chromosome system has been determined are members of the endemic New Zealand genus Leiopelma. Two species, Leiopelma pakeka and Leiopelma hochstetteri, have female heterogamety of the ZW/ZZ and 0W/00 types, respectively. Despite its great karyotypic similarity to L. pakeka, a third species, Leiopelma archeyi, has not been know previously to possess heteromorphic sex chromosomes. Herein a highly differentiated putative W chromosome characterized by the addition of a completely heterochromatic short arm is reported from a female L.archeyi from the Whareorino forest of the North Island of New Zealand.Abstract
C-banded chromosomes from a female Leiopelma archeyi (DMG 5136) from Whareorino. The heteromorphic putative sex chromosome pair No. 9 (Z and W) are indicated (thick arrows and box). An interstitial C-band appears of one homolougue of chromosome No. 7 (small arrows) and a block of heterochromatin is variably expressed at the centromere of chromosome No. 6 (asterisks)