Research Article |
Corresponding author: Uwe Kaulfuss ( uwe.kaulfuss@otago.ac.nz ) Academic editor: Allen Sanborn
© 2015 Uwe Kaulfuss, Max Moulds.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Kaulfuss U, Moulds M (2015) A new genus and species of tettigarctid cicada from the early Miocene of New Zealand: Paratettigarcta zealandica (Hemiptera, Auchenorrhyncha, Tettigarctidae). ZooKeys 484: 83-94. https://doi.org/10.3897/zookeys.484.8883
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A new genus and species of primitive cicada (Hemiptera: Tettigarctidae) is described from the early Miocene of southern New Zealand. Paratettigarcta zealandica gen. et sp. n. is the first cicada (Cicadoidea) fossil from New Zealand and exhibits wing venation patterns typical for the subfamily Tettigarctinae. It differs from other fossil taxa and the extant genus Tettigarcta in the early divergence of CuA2 from the nodal line in the forewing, its parallel-sided subcostal cell, the early bifurcation of vein M and long apical cells of the hindwing, and in wing pigmentation patterns.
Cicadoidea , Tettigarctidae , Miocene, New Zealand, Hindon Maar, Otago
Tettigarctidae (hairy cicadas) is the sister-group to singing cicadas (Cicadidae) from which they are distinguished by various morphological characters such as the greatly expanded pronotum (concealing much of the mesonotum), timbals present in both sexes, a completely developed forewing venation with the radial sector arising near the wing base and veins 1A and 2A separated, and a well-developed, conspicuous nodal line on the forewing (
The fossil record of family Tettigarctidae (summarised in
Here we describe Paratettigarcta zealandica gen. et sp. n. as the first cicada fossil from New Zealand and, as it is of early Miocene age, the youngest fossil record of Tettigarctidae. This new genus and species comes from a newly discovered paleontological site at Hindon Maar in southern New Zealand and a brief discussion is presented of the depositional setting and the age of the locality as it is currently known.
Hindon Maar is a new paleontological site in Otago, South Island, New Zealand, ~10 km N of Outram, near Dunedin (45°45.62'S; 170°15.88'E; Fig.
The circular topographic basin, coinciding with an aeromagnetic high and situated in a monogenetic volcanic field, as well as the bedded pyroclastic deposits at the basin margin are all features typically associated with partly eroded maar-diatreme volcanoes, while the fine-grained laminated, biogenic sediment argues for (but is not restricted to) deposition in a maar-lake. The geological and paleontological evidence that is currently available thus suggests that Hindon Maar is a maar-type fossil lagerstätte that may contribute significantly to our understanding of Neogene Australasian biodiversity in the future.
The early Miocene age of Hindon Maar is based on palynology of the lacustrine sediments and on radiometric ages previously published for Waipiata volcanic rocks. K-Ar and 40Ar/39Ar ages provided by
The studied fossil comprises overlapping fragments of a hind and forewing preserved as part and counterpart (Fig.
Photomicrographs were taken with a Canon T3 camera attached to a Nikon SMZ1000 stereomicroscope. Wetting the specimen with ethanol accentuated the visibility of venation patterns and outlines of the wings. Photomicrographs taken at several depths of field were stacked using Photoshop CS5.1 software (Adobe Systems Inc.). Our terminology of wing venation and cells follows that of
Paratettigarcta zealandica new species, designated herein (Figs
Paratettigarcta is most similar in hindwing venation to that of Eotettigarcta Zeuner, 1944 from the Paleocene of the United Kingdom (Eotettigarcta is known only from a partial hindwing) but differs in its more parallel-sided subcostal cell (the most anterior of the distal cells) where RA lies parallel to Sc for most of its length rather than gradually diverging, and in the branching of vein M where M1 branches before M3 (after in Eotettigarcta). There are also similarities in the forewing of Paratettigarcta with extant Tettigarcta from which Paratettigarcta differs in the early divergence of CuA2 from the nodal line in the forewing (late divergence in Tettigarcta). The hindwing of Paratettigarcta is quite different from that of Tettigarcta, especially in the apical cells that are much longer than those of Tettigarcta, in particular the anterior most cell (subcostal cell) that is wide and extended far beyond crossvein r (narrow and only a little extended beyond r in Tettigarcta). Further, Paratettigarcta has pigmented wing patterns not unlike those present in Eotettigarcta (and some other fossil Tettigarctidae) but such patterns are absent in extant Tettigarcta.
Forewing veins R and M branched close to base of forewing so that ulnar cells u1-u3 and medial cell are long and narrow; vein CuA strongly bowed before branching. Nodal line clearly defined and departing the extremity of vein CuA2. Crossvein r-m nearly straight, steeply angled to RP and M1; m gently bowed, almost perpendicular to M2 and M3; m-cu strongly bowed, meeting M4 nearly perpendicularly and meeting CuA1 at a steep angle. Hindwing apical cells tending long and narrow, a1 almost as long as a2 so that crossvein r meets RA within its proximal quarter; Sc and RA wide apart, almost as wide as width of apical cell 1.
The genus name is a combination of para (Latin from Greek, meaning “near”) and the extant genus-group name Tettigarcta.
Paratettigarcta zealandica sp. n. differs from other Tettigarctidae by the attributes discussed in the generic diagnosis above. In particular the forewing of Paratettigarcta zealandica, that is remarkably similar to extant T. crinita Distant, 1883 (Fig.
Tettigarcta crinita Distant, fore and hindwings; areas of the wings preserved in the new fossil species are indicated (modified from
Line drawings of Paratettigarcta zealandica gen. et sp. n., holotype OU45476 A overlapping fore and hindwing as preserved B forewing and C hindwing, pigmented areas shown as preserved. A apical cell av ambient vein C costal vein CuA cubitus anterior vein CuP cubitus posterior vein M median vein; medial crossvein mc medial cell m-cu mediocubital crossvein nl nodal line R radius r radial crossvein RA radius anterior r-m radiomedial crossvein RP radius posterior Sc subcostal vein. Scale bar: 5 mm.
Holotype. Forewing similar to extant Tettigarcta in size, shape and venation (compare Figs
Holotype OU45476, hind and forewing from lacustrine mudstones at Hindon Maar (early Miocene; I44/f0392 in the New Zealand Fossil Record File), Waipiata Volcanic Field, 10 km N of Outram, Otago, southern New Zealand; deposited in the Department of Geology, University of Otago.
The species name refers to New Zealand, where this species was distributed in the Miocene.
Paratettigarcta zealandica gen. et sp. n. appears closest to Eotettigarcta scotica based on the hindwing venation (the latter known only from a partial hindwing). In particular Sc and RA are widely separated, and it is likely that the apical cells are of similar length with a1 being almost as long as a2. If that is so then Paratettigarcta is best placed in the tribe Protabanini of the subfamily Tettigarctinae, family Tettigarctidae, following the classification of
The forewing venation of P. zealandica shows a clear affinity with that of extant species of Tettigarcta of which there are only two closely related species, T. crinita and T. tomentosa (
The discovery of a Paratettigarcta zealandica at Hindon Maar in southern New Zealand documents the presence of family Tettigarctidae in Australasia in the early Miocene. It thus partially fills the spatial and temporal gap that existed between the next youngest Tettigarctidae fossil from the mid-Eocene of Germany (
By the early Miocene, New Zealand had been an isolated island landmass for at least 57 My, following separation from Australia in the Late Cretaceous. Two biogeographical scenarios can consequently be hypothesised to explain the occurrence of Tettigarctidae at Hindon Maar: (1) colonization of New Zealand via trans-oceanic dispersal of members of this family in or before the early Miocene, for example from Australia or New Caledonia, as proposed for the Cicadidae (
We are deeply grateful to the Neehoff family for allowing access to their property and for making excavations at Hindon Maar possible. We thank Daphne Lee (Department of Geology, OU) for organizing these excavations and for improving the manuscript. Jennifer Bannister (Department of Botany, OU) and Dallas Mildenhall (GNS, Lower Hutt) kindly provided botanical and palynological information. The Otago Regional Council made available aeromagnetic data from the Glass Earth Survey. We would like to thank Dmitry Shcherbakov (Paleontological Institute RAS, Moscow) and an anonymous reviewer for valuable and constructive comments. Support for this study was provided by a University of Otago Research Grant, a Marsden Grant from the Royal Society of New Zealand, and by the National Science Foundation, grant number DEB 09-55849 (awarded to Chris Simon, University of Connecticut).