The chromosomes of the hystricomorphous family Ctenodactylidae (Rodentia: ?Sciuromorpha) and their bearing on the relationships of the four living genera

Abstract

Karyotype studies support the view that modern genera of the family Ctenodactylidae originated in Africa. Karyotype differences between the genera are less obvious than morphological differences but coincide in relating Massoutiera to Felovia and deriving this line from the Pectinator‐like ancestor which, in turn, was closely related to a Ctenodactylus ancestor. 43% of the chromosomes are standard throughout the family; 25% seem to be very susceptible to fragmentation, translocation and inversion. These changeable chromosomes are the only ones that show differences in their G‐band patterns. The ctenodactylid karyotype resembles caviomorph karyotypes in its NF, predominantly metacentric chromosomes and in its nucleolar organiser, or marker, chromosomes.

A comprehensive phylogeny of the gundis (Ctenodactylinae, Ctenodactylidae, Rodentia)

“…The very close relationship between Massoutiera and Felovia is unsurprising due to their similar morphology. This result is in agreement with the analyses carried out by George (1979George ( , 1985.…”

“…Wood (1977) suggested that Pectinator spekei seemed derivable from Africanomys and Metasayimys, an opinion with which we agree. As defended by some authors (Jaeger 1971;George 1979George , 1985, Pectinator spekei is the most basal of the living species of Ctenodactylinae. This taxon shares an exclusive common ancestor with the species of the Ihroudia clade and the more derived ctenodactylines.…”

“…The latter would in fact be closer to Ctenodactylus vali than to Pectinator spekei according to the George (1979) indices, but this last taxon was not included in the present analysis due to incomplete data. Massoutiera mzabi and Felovia vae are closer to one another than to the other two taxa.…”

“…Previous works George (1979). George (1979) tried to decipher the relationships within the extant ctenodactylids based on their karyotypes.…”

“…George (1979) tried to decipher the relationships within the extant ctenodactylids based on their karyotypes. With this end in view, she calculated an index of dissimilarity based on differences in chromosome length and centromere position.…”