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Alcheringa: An Australasian Journal of Palaeontology ISSN: 0311-5518 (Print) 1752-0754 (Online) Journal homepage: http://www.tandfonline.com/loi/talc20 Protodammara reimatamoriori, a new species of conifer (Cupressaceae) from the Upper Cretaceous Tupuangi Formation, Chatham Islands, Zealandia Chris Mays & David J. Cantrill To cite this article: Chris Mays & David J. Cantrill (2018): Protodammara reimatamoriori, a new species of conifer (Cupressaceae) from the Upper Cretaceous Tupuangi Formation, Chatham Islands, Zealandia, Alcheringa: An Australasian Journal of Palaeontology, DOI: 10.1080/03115518.2017.1417478 To link to this article: https://doi.org/10.1080/03115518.2017.1417478 Published online: 04 Jan 2018. Submit your article to this journal View related articles View Crossmark data Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=talc20 Download by: [Naturhistoriska Riksmuseum] Date: 05 January 2018, At: 02:26 Protodammara reimatamoriori, a new species of conifer (Cupressaceae) from the Upper Cretaceous Tupuangi Formation, Chatham Islands, Zealandia CHRIS MAYS and DAVID J. CANTRILL Mays, C. & Cantrill, D.J., January 2018. Protodammara reimatamoriori, a new species of conifer (Cupressaceae) from the Upper Cretaceous Tupuangi Formation, Chatham Islands, Zealandia. Alcheringa XXX,X–X. ISSN 0311-5518. Isolated conifer female reproductive structures are common fossil elements from Cenomanian (ca 99–94 Ma) charcoal- and resin-rich beds of the Tupuangi Formation, Chatham Islands, southwest Pacific Ocean. Recent findings have proposed that these are the oldest fossil evidence of serotiny, a highly successful fire-adaptive reproductive strategy common among tree species living in fire-prone areas today. Herein, we systematically describe the external morphological and anatomical features of these fossils, by employing a combination of manual extraction and neutron tomogra- phy techniques. We propose a new species of conifer, Protodammara reimatamoriori, and a re-examination of fossil material of the Protodammara type species facilitated an emendation of the genus. Protodammara shares numerous features with extant Cunninghamia, Taiwania, Athrotaxis, and several extinct taxa of Cupressaceae, and is interpreted as an extinct lineage of the early-divergent ‘taxodioid Cupressaceae’ stem group. Chris Mays [[email protected]] Department of Palaeobiology, Swedish Museum of Natural History, Frescativägen 40, Stockholm 114 18, Sweden; School of Earth, Atmosphere and Environment, Monash University, 9 Rainforest Walk, Clayton, VIC 3800, Australia; David J. Cantrill [[email protected]] Royal Botanic Gardens Victoria, Private Bag 2000, South Yarra, VIC 3141, Australia; School of BioSciences, University of Melbourne, Parkville, VIC 3010, Australia. Received 17.9.2017; revised 7.12.2017; accepted 12.12.2017. Key words: Palaeobotany, ovuliferous complex, Cenomanian, fire ecology, polar forest, taxonomy. THE TUPUANGI FORMATION flora of the Chatham Brown et al. 2012). This study seeks to establish a new Islands is characterized by a low diversity of ferns, species designation encompassing these organically pre- lycophytes and non-vascular plants, a high abundance served conifer fossil specimens. Comparable fossils and diversity of Gondwanan conifers (Araucariaceae, have been described for over 130 years from the Cupressaceae and Podocarpaceae), and subsidiary Northern Hemisphere (Heer 1882), but this is the first Ginkgoales and angiosperms (Pole & Philippe 2010, such record from the Southern Hemisphere. Mays et al. 2015a, 2015b, 2017b). One form of fossil conifer ‘seed cone scale’ (ovuliferous complex or ‘OC’ herein; see ‘materials and methods’ section) was found Geological setting to be particularly common in layers with high charcoal Downloaded by [Naturhistoriska Riksmuseum] at 02:26 05 January 2018 The Tupuangi Formation is expressed in outcrops of the and fossil resin (amber) content. Both conventional Chatham Islands, southwest Pacific, an archipelago near manual preparation and non-destructive neutron tomog- the eastern margin of the largely submerged continent, raphy were employed to study the fossils, the latter Zealandia (Fig. 1). This continent, which also includes technique revealing the resin canals’ anatomy based on New Zealand, Lord Howe Island, New Caledonia and the anomalously high neutron attenuation of the in situ Campbell Island, is almost entirely under water today resin compared with the surrounding organic fossil (Mortimer et al. 2017), but was largely emergent remains and matrix. This constellation of evidence during the deposition of the Tupuangi Formation revealed an adaptive function of the resin in response to (Campbell et al. 1993). The Tupuangi Formation has regular fire during the mid-Cretaceous (Mays et al. been biostratigraphically correlated to the Ngaterian– 2017a). This interval likely had the highest proportions Mangaotanean New Zealand Chronostratigraphic stages of atmospheric oxygen since the late Palaeozoic (Mildenhall 1994, Mays & Stilwell 2013); these corre- (Bergman et al. 2004, Glasspool & Scott 2010), which spond to the Cenomanian–Turonian Global Chronos- would have promoted the frequency and intensity of tratigraphic stages (ca 99–90 Ma, Raine et al. 2015). wildfires around the globe (Belcher et al. 2010, The unit was deposited in a vast riverine-deltaic system (Campbell et al. 1993) within the south polar circle (75–80°S; Markwick et al. 2000). © 2018 Geological Society of Australia Inc., Australasian Palaeontologists https://doi.org/10.1080/03115518.2017.1417478 2 CHRIS MAYS AND DAVID J. CANTRILL ALCHERINGA Downloaded by [Naturhistoriska Riksmuseum] at 02:26 05 January 2018 Fig. 1. A, Map of eastern Zealandia, boxed area in Fig. 1B, grey areas = emergent, grey outline = 2000 m isobath. B, Map of the Chatham Islands region, boxed areas in Fig. 1C, D, grey areas = emergent. C, D, Generalized geological maps with fossil localities recorded in this study, all local- ity numbers have the locality prefix ‘CH/f’ as outlined in the text; C, Waihere Bay area, northwest Pitt Island; D, Tupuangi Beach area, northeast Pitt Island. Modified from Mays et al. (2015b) with permission. Materials and methods outcrop succession at southern Tupuangi Beach Localities have GNS Fossil Record File numbers (prefix (Fig. 1). Stratigraphic heights of the localities corre- ‘CH/f’), and all (except CH/f0815) are from the spond to the outcrop successions illustrated by Mays & Waihere Bay outcrop succession; CH/f0815 is from an Stilwell (2013, Fig. 4 therein). Fossil material was ALCHERINGA PROTODAMMARA REIMATAMORIORI 3 collected by C.M., D.J.C., P. Viegas, and T. Ziegler dur- Order CUPRESSALES Link, 1831 ing January–February, 2016. All fossil materials are Family CUPRESSACEAE Gray, 1821 housed at GNS Science, Lower Hutt, New Zealand. Hand samples have been assigned unique sample regis- Protodammara Hollick & Jeffrey, 1906 emend. tration (‘GNS reg.’) numbers (prefixed ‘PL’), and Type species. Protodammara speciosa Hollick & Jeffrey, labelled with field numbers (prefixed ‘TPF’). In cases 1906. Lectotype (designated herein): 52818-1A where more than one fossil specimen was found associ- (Harvard University Herbaria); plate 1, Fig. 5 of Hollick ated with a hand sample, these specimens are provided & Jeffrey (1906). with letter codes (Table 1). Type locality. Kreischerville, Staten Island NY, Raritan Fifty-four fossil specimens (excluding seven speci- Formation, ca Turonian. men counterparts) are reported herein. These are pre- served on or within 33 hand samples (PL1228–60); all Emended generic diagnosis. Ovuliferous cone scale specimens, except one, PL1235 (and its counterpart, complexes. Lignified, resinous. Spatulate in outline, PL1236A), can be ascribed to the newly erected species, pedicellate base, flattened, thickening distally. Bracts Protodammara reimatamoriori. All specimens are from have transverse ridge(s) subparallel to distal margin on strata of the Ngaterian and Arowhanan New Zealand one or both of the abaxial and adaxial surfaces. Ovulif- chronostratigraphic stages (Mays & Stilwell 2013), erous scale entirely fused with bract or otherwise indis- corresponding to the Cenomanian global chronostrati- tinct. Three seeds/ovules aligned in a single straight or graphic stage (ca 99–94 Ma, Raine et al. 2015). curved transverse row on the adaxial surface. Three or All except two compression and impression fossils more resin canals occur at the base of the ovuliferous were at least partly exposed by manual extraction; spec- complex; additional canals originate de novo or by imens PL1231G, PL1231H have no surface expressions, bifurcation. Variously developed apical process ener- and remain entirely encapsulated within sedimentary vated by a medial abaxial resin canal. matrix. Eight specimens were examined with neutron tomography (NT) from two hand samples (PL1231, Remarks. It was considered prudent to emend the gen- PL1244), using the experimental setup outlined by eric diagnosis slightly to accommodate the newly Mays et al. (2017b); the specific NT scan parameters described species, P. reimatamoriori, rather than erect a were presented by Mays et al. (2017a, table DR3 new genus for specimens of such close morphological therein). Resin volume estimates are based on the digi- and anatomical similarity to the type species. For a dis- tal reconstructions of these eight specimens; the details cussion of these similarities, see the Discussion section. of estimating