Extensive Robertsonian rearrangement: implications for the radiation and biogeography of Planipapillus Reid (Onychophora: Peripatopsidae)

摘要: The remarkable diversity in chromosome number within Planipapillus Reid 1996, the most speciose genus of peripatopsid onychophorans, centred alpine region south-eastern Australia is documented. Robertsonian, whole-arm rearrangements account for twofold range diploid numbers Planipapillus. Ooperipatellus Ruhberg 1985, another clade oviparous shows a very different pattern, with no karyotypic among species from and New Zealand. Rate constancy chromosomal evolution genera would indicate an ancient radiation Planipapillus, extant representing relictual survivors more recent Pleistocene climatic upheavals. Conversely, if are result rapid restructuring, may be attributed to population fragmentation isolation resulting repeated glaciation warming cycles rather than stemming radiation. Data other animal groups support model accelerated rates Robertsonian centric fusions concordant Karyotype change important factor generation maintenance diversity.