New Zealand broke away from the Australian and Antarctic sections of the ancient supercontinent of Gondwana roughly 130 million years ago, and has developed a unique flora and fauna made up of the descendants of animals and plants that were present at the time of this split, plus the decedents of a few species that have managed to reach the landmass since. Prior to the arrival of the first Humans on the islands 800 years ago, there were only three Mammal species present throughout the whole of New Zealand, all of them Bats. Of these, one species,
Chalinolobus tuberculatus, has close relatives in Australia, and is thought to have reached New Zealand less than two million years ago. The other two species,
Mystacina tuberculata and
Mystacina robusta, are placed in their own family, the Mystacinidae, also known as Burrowing Bats, due to the large amounts of time they spend on the ground foraging under leaf litter. These Bats are found nowhere other than New Zealand today, though fossil specimens are known from the Oligocene and Miocene of Australia and the Miocene of New Zealand. Burrowing Bats are considered to be members of the Noctilionoidea, the Bat superfamily that also includes the American groups Phyllostomidae (Leaf Nosed Bats), Noctilionidae (Bulldog Bats), Mormoopidae (Moustached Bats), Furipteridae (Smokey and Thumbless Bats), and Thyropteridae (Disk-winged Bats), and possibly the Madagascan Myzopodidae (Sucker-footed Bats).
In a
paper published in the journal
Scientific Reports on 10 January 2018,
Suzanne Hand of the
PANGEA Research Centre at the
University of New South Wales,
Robin Beck of the
School of Environment and Life Sciences at the
University of Salford,
Michael Archer, also of the PANGEA Research Centre at the University of New South Wales,
Nancy Simmons of the
Department of Mammalogy at the
American Museum of Natural History, Gregg Gunnell of the
Division of Fossil Primates at the
Duke University Lemur Center,
Paul Scofield of the
Canterbury Museum,
Alan Tennyson of the
Museum of New Zealand Te Papa Tongarewa, Vanesa De Pietri, also of the Canterbury Museum,
Steven Salisbury of the
School of Biological Sciences at
The University of Queensland, and
Trevor Worthy of
Biological Sciences at
Flinders University, describe a new species of Burrowing Bat from the Early Miocene St Bathans fossil assemblage of the Otago Region of South Island, New Zealand.
The new species is named
Vulcanops jennyworthyae, where '
Vulcanops' means 'Vulcan Bat' in reference to the volcanic nature of much of New Zealand, and the Vulcan Hotel in St Bathans, and '
jennyworthyae' honours Jennifer Worthy of the
School of Biological, Earth and Environmental Sciences at the University of New South Wales, for her work on the fauna of the St Bathans fossil assemblage. The species is described from a single fragment of left dentary (jawbone) with two molar teeth, plus a series of detached teeth.
Vulcanops jennyworthyae, Bannockburn Formation, St Bathans, Central Otago, New Zealand. Lower dentition. Left dentary fragment containing m2-3. (a) Buccal view; (b–b’) stereopair, occlusal view; (c) lingual view m2-3. Right molar (d–d’) Stereopair, oblique occlusal view; (e) buccal view; (f) occlusal view. Abbreviations: cld, cingulid; co, cristid obliqua; end, entoconid; ecd, entocristid; hyd, hypoconid; hyl, hypoconulid; med, metaconid; pacd, paracristid; pad, paraconid; pcd, postcristid; prcd, protocristid; prd, protoconid; tal, talonid; trig, trigonid. Scale bars are 2 mm. Hand et al. (2018).
Vulcanops jennyworthyae appears to have been fairly large for a Bat, with an estimated mass of 40 g. The dentition of this species suggests that it was omnivorous, as is the case with modern Burrowing Bats, which eat a range of Arthropods and plant matter, though the larger size of the specimen the presence of a large hypocone on its upper molars, suggests that it might have been capable of taking larger prey than its modern relatives, possibly including small Vertebrates.
A phylogenetic analysis of the Noctilionoidea including
Vulcanops jennyworthyae did not support the idea that the Madagascan Myzopodidae are members of this group, or even closely related to it, though it did suggest that some fossil Bats from the Eocene of Egypt may be closely related to the group. This is consistent with a model in which the ancestors of the Noctilionoidea split from their closest ancestors in Africa during the Eocene, and spread across South America, Antarctica and Australia to New Zealand during the Oligocene and Miocene, when Australia, Antarctica and South America were all connected and New Zealand, though already an island, was still much closer to Australia and Antarctica. At this time Antarctica was still largely covered by forest (the preferred habitat of most Bats), with tropical forests covering much of the continent about 50 million years ago, which was replaced by temperate forests by 15 million years ago.
See also...
