Triunia robusta, which until recently was thought to be
extinct, is now classified nationally as endangered. It is an understorey
species restricted to the subcoastal rainforests in a small region of the
Sunshine Coast, Queensland. The project involved sampling the genetic
variation and measuring the population size and size distribution of
T. robusta and its geographically closest congener
T. youngiana, which occurs further south and has a wider
geographic distribution. A total of 877 T. robusta
plants were recorded across the 11 populations, approximately half
(56.8%) of these were juveniles less than 1 m tall, whereas in
T. youngiana only about 36.4% of a population was
composed of juveniles. Genetic diversity was similar but significantly higher
for T. robusta than T. youngiana
if the very small T. robusta populations (2 or 3 plants)
were excluded from analysis (P < 0.05). The mean
percentage of polymorphic loci among populations was high for both species.
Triunia robusta is not, on average, more inbred than the more common
T. youngiana. There was more differentiation between the
T. robusta populations, which were in close proximity,
than between the more geographically separated
T. youngiana populations. Thus, there is evidence of
more gene flow between populations of T. youngiana than
between those of T. robusta. However, there was no
geographic relationship between genetic similarity and geographic proximity in
T. robusta
Conservation Genetics of Crested Newt Species Triturus cristatus and T. carnifex within a Contact Zone in Central Europe: Impact of Interspecific Introgression and Gene Flow
