Analyses of the mitochondrial genome of Leiopelma hochstetteri argues against the full drowning of New Zealand

Abstract

Aim We used endemic frogs to test the hypothesis that New Zealand was fully submerged during the Oligocene marine transgression (c. 25-35 Ma, the Oligocene drowning) and that all the land biota subsequently arrived by dispersalincluding the poorly dispersing frogs.Location New Zealand. MethodsThe complete mitochondrial genome of the New Zealand native frog Leiopelma hochstetteri was sequenced, assembled and analysed, and compared with that of L. archeyi.Results Using many phylogenetic analyses we examined the evolutionary relationships of the two species of Leiopelma, both for the deepest divergence within New Zealand and relative to other frogs. Our results give estimates of well over 65 Ma for the first divergence of leiopelmatid frogs within New Zealand, and over 150 Ma for the divergence of Leiopelma from its closest relative, the North American tailed frog Ascaphus truei. Main conclusionsThe identification of such a deep divergence among the extant Leiopelma species provides some of the strongest support yet for a mixed-age model for the origin of New Zealand's terrestrial biota, where some elements are of vicariant origin and others have arisen by long-distance dispersal. This contradicts a full drowning model and supports the view that there must have been some continuous land through the Oligocene.

Metapopulation vicariance explains old endemics on young volcanic islands

“…However, metapopulations also have a biogeographical and geological context, and they may persist for tens of millions of years. For example, in molecular clock studies the frog Leiopelma hochstetteri , endemic to the New Zealand archipelago, has been dated as Cretaceous (67 Ma; Carr et al., ).…”

The enigmatic pattern of long‐distance dispersal of minute freshwater gastropods (Caenogastropoda, Truncatelloidea, Tateidae) across the South Pacific

“…Also Vanuatu with its complex history of repeated sea level changes would have been colonized more than a million years earlier than assumed by Zielske & Haase (2014a), which is hard to match with the geological evidence (Taylor, 1992;Robin et al, 1993). Similarly, the onset of the radiation in NZ would predate the re-emergence of all or at least much of NZ by several millions of years (Trewick et al, 2007; but see Mildenhall et al, 2014;Carr et al, 2015). Therefore, we base the following discussion on the age estimates of the Rapa Iti/COI rate calibration if not otherwise stated.…”

“…However, although intensely debated, NZ and NC may also be considered oceanic regarding the evolution of their biota as both have probably experienced long phases of significant submergence until the late Eocene and late Oligocene respectively (Waters & Craw, 2006;Murienne, 2009;Carr et al, 2015). The dominant sources of terrestrial and freshwater biota for colonization of the SP islands are Malesia and South-east Asia, as well as Australia.…”

History Repeats: Large Scale Synchronous Biological Turnover in Avifauna From the Plio-Pleistocene and Late Holocene of New Zealand

“…Zealandia is therefore best thought of not as a coherent terrestrial entity, but rather as a region of the ocean where diverse geological processes have created a scatter of archipelagos and ephemeral islands (Grandcolas, 2017). While a complete submergence of the New Zealand region has been suggested (Landis et al, 2008), recent geological, palaeontological (e.g., Conran et al, 2014;Scott et al, 2014;Worthy et al, 2017) and genetic research (e.g., Carr et al, 2015; Wallis and Jorge, 2018) strongly favors a small emergent archipelago at that time. Wallis and Jorge (2018) synthesized previous evolutionary genetic studies and found around 75% of 248 New Zealand lineages survived the marine transgression in situ, the majority non-volant terrestrial and freshwater taxa, and trees.…”