The purpose of the present study is to examine the genetic and morphological variation found in narrow-range endemic terrestrial invertebrate species at different geographic scales, and the ramifications of this for their systematics, management and conservation. The listed endangered land snail Meridolum corneovirens and several related forms are restricted to the Sydney region, and were used to address the above issues. Morphological, anatomical, allozyme and DNA data were obtained for a total of 77 populations from across the known range of Meridolum. A particular emphasis was placed on the forms found across the Sydney region. The analysis of the different datasets, both individually and in combination indicate at least 35 taxa mostly parapatric and seven genera were represented. This includes several previously unrecognised taxa. The analysis supports the conclusion that Meridolum corneovirens belongs to a new genus. This includes several species found from eastern Sydney south along the coast to Nowra. A total of six new species and five new genera are described. The conservation and management of narrow-range endemics such as Meridolum corneovirens provide a number of challenges to conservation managers. The alternative of listing a gene pool rather than listing species separately is proposed and explore / Doctor of Philosophy (PhD)

The purpose of the present study is to examine the genetic and morphological variation found in narrow-range endemic terrestrial invertebrate species at different geographic scales, and the ramifications of this for their systematics, management and conservation. The listed endangered land snail Meridolum corneovirens and several related forms are restricted to the Sydney region, and were used to address the above issues. Morphological, anatomical, allozyme and DNA data were obtained for a total of 77 populations from across the known range of Meridolum. A particular emphasis was placed on the forms found across the Sydney region. The analysis of the different datasets, both individually and in combination indicate at least 35 taxa mostly parapatric and seven genera were represented. This includes several previously unrecognised taxa. The analysis supports the conclusion that Meridolum corneovirens belongs to a new genus. This includes several species found from eastern Sydney south along the coast to Nowra. A total of six new species and five new genera are described. The conservation and management of narrow-range endemics such as Meridolum corneovirens provide a number of challenges to conservation managers. The alternative of listing a gene pool rather than listing species separately is proposed and explore / Doctor of Philosophy (PhD)