New Zealand is an archipelago that is both geographically and climatically diverse. Recently, it has been stated that the decline in biological diversity is New Zealand's most pervasive environmental issue. The impact of potential pressures such as micro-habitat loss and fragmentation on the liverwort flora have not been previously investigated. This is alarming because it is estimated that New Zealand has c. 10% of the world's liverwort species, and more importantly, has 48 of the 73 liverwort families. Because of these factors together with the high level of endemism, the liverwort flora of New Zealand is considered to be of worldwide significance. First, this study identified potential threats to the New Zealand liverwort flora, and second, developed a preliminary checklist of threatened liverworts to be considered as candidates for the World Red List. Selection of species was based on field studies spanning three decades, extensive herbarium records, and bibliographic references. Case studies illustrating the different categories of threat occurring in New Zealand include examples from a monotypic family and a monotypic genus. We conclude that research relating to the conservation biology of the New Zealand hepatic flora requires great urgency and recommend areas of priority.

Key words: conservation, liverworts, New Zealand, rare and threatened liverworts