This article appeared in a journal published by Elsevier. The attachedcopy is furnished to the author for internal non-commercial researchand education use, including for instruction at the authors institution

and sharing with colleagues.

Other uses, including reproduction and distribution, or selling orlicensing copies, or posting to personal, institutional or third party

websites are prohibited.

In most cases authors are permitted to post their version of thearticle (e.g. in Word or Tex form) to their personal website orinstitutional repository. Authors requiring further information

regarding Elsevier’s archiving and manuscript policies areencouraged to visit:

http://www.elsevier.com/copyright

Author's personal copy

Palynology of the Lower Triassic succession of Tulong, South Tibet — Evidence forearly recovery of gymnosperms

Elke Schneebeli-Hermann a,⁎, Peter A. Hochuli a, Hugo Bucher a, Nicolas Goudemand a,Thomas Brühwiler b, Thomas Galfetti c

a Institute and Museum of Palaeontology, University of Zurich, Karl Schmid-Str. 4, CH-8006 Zurich, Switzerlandb Bachtelstrasse 18, CH-8400 Winterthur, Switzerlandc Holcim Group Support Ltd. Materials Technology, Im Schachen, CH-5113 Holderbank, Switzerland

a b s t r a c ta r t i c l e i n f o

Article history:Received 8 November 2011Received in revised form 27 March 2012Accepted 10 April 2012Available online 18 April 2012

Keywords:Early TriassicPalynologyRecoveryPalaeoclimateTulong FormationSouth Tibet

The thermally altered but otherwise well preserved Early Triassic palynomorphs from the Tulong area (SouthTibet) allowed for qualitative and quantitative analyses and the differentiation of two distinct palynofloras, aSmithian lycopod-dominated flora and a Spathian gymnosperm-dominated flora. This suggests that gymno-sperm vegetation recovered about 2 Ma after the end-Permian event on the subtropical North Indian Margin.Together with previously described successions from Pakistan, Australia, and Norway the new palynofloralrecord suggests an earlier establishment of diverse, gymnosperm-rich plant communities after the end-Permian event than previously proposed. The observed change in the ratio of the two major plant groups(pteridophytes/gymnosperms) in these two assemblages supports the global extent of a major climatechange near the Smithian–Spathian boundary. The observed palynofloral patterns are closely related to thechanges in the carbon isotope record, which suggests that the floral recovery dynamics were linked to envi-ronmental conditions.

© 2012 Elsevier B.V. All rights reserved.

1. Introduction

Following the end-Permian mass extinction the Early Triassic wasmarked by major faunal and floral reorganisation and recovery (e.g.Orchard, 2007; Brayard et al., 2009; Hochuli et al., 2010a,b;Hautmann et al., 2011; Hermann et al., 2011a). Numerous floral re-cords show a turnover in Late Permian assemblages initiating the fad-ing of Permian floral province distinctness and the establishment ofcosmopolitan flora in the earliest Triassic (see e.g. Retallack, 1995;Foster et al.;, 1997; Hochuli et al., 2010a, and references therein). Inthe semi-arid tropical Central Europe, conifer forests disappearedduring the Early Triassic and were replaced by lycopod-vegetation,dominated by Pleuromeia (Looy et al., 1999), whereas in the humidtropical areas of South China rich and diverse fern assemblageswere successively replaced by gymnosperms (Lunatisporites) associ-ated with lycopod taxa (Lundbladispora, Aratrisporites) typical for nu-merous Lower Triassic successions worldwide (Hochuli et al., 1989;Hankel, 1991; Looy et al., 1999; Peng et al., 2006; Kürschner andHerngreen, 2010). At least for Central Europe it has been proposedthat gymnosperm forests did not recover until the Middle Triassic(Looy et al., 1999).

On the North Indian Margin (NIM) (Maheshwari, 1982), welldated and well preserved Early Triassic palynofloral records aregenerally scarce due to extensive thermal alteration during theHimalayan orogeny (e.g. Tiwari et al., 1996). In the Tulong areaEarly Triassic marine fauna and palaeoenvironments have been stud-ied in detail by several authors (Liu and Einsele, 1994; Garzanti et al.,1998; Brühwiler et al., 2009; Forel et al., 2011) and a robust ammo-noid biostratigraphic framework exists (Brühwiler et al., 2009,2010). However, palynological studies from this area are rare or stra-tigraphically restricted. At Qubu, east of Tulong, abundant pteridophytespores and acritarchs of Late Permian age were mentioned from theuppermost part of the Qubuerga Formation (Nimaluoshenza Member)(Shen et al., 2006). Concentrating on the Permian–Triassic boundaryinterval in the Tulong area Rao and Zhang (1985) observed threepalynological assemblages from the Upper Permian NimaluoshenzaMember. The oldest assemblages include gymnosperm generasuch as Falcisporites, Lueckisporites, Striatites (probably corre-sponds to Protohaploxypinus) Vitreisporites, Platysaccus, andVesicaspora. Pteridophytes are represented by Maculatasporites,Polypodiisporites, Didecitriletes, Granulatisporites, Densoisporites,Punctatisporites, Retusotriletes, and Acanthotriletes. In the two over-lying assemblages the diversity of spores decreases and gymno-sperms seem to be absent in the middle assemblage. New generaare Leiotriletes, Cyclogranisporites, Dictyophyllidites, and in theyoungest assemblage Aratrisporites. Acritarchs are present in allthree assemblages (Rao and Zhang, 1985). Mesozoic assemblages

Palaeogeography, Palaeoclimatology, Palaeoecology 339–341 (2012) 12–24

⁎ Corresponding author at: Palaeoecology, Department of Physical Geography, UtrechtUniversity, Budapestlaan 4, 3584 CD Utrecht, The Netherlands. Tel.: +31 30 253 26 47;fax: +31 30 253 50 96.

E-mail address: ElkeSchneebeli@gmx.net (E. Schneebeli-Hermann).

0031-0182/$ – see front matter © 2012 Elsevier B.V. All rights reserved.doi:10.1016/j.palaeo.2012.04.010

Contents lists available at SciVerse ScienceDirect

Palaeogeography, Palaeoclimatology, Palaeoecology

j ourna l homepage: www.e lsev ie r .com/ locate /pa laeo

Author's personal copy

of ?Middle Jurassic to Cretaceous age have been described from theTanggula Mountains and Gangdise Mountains, North of Tulong (Liand Batten, 2004; Li et al.;, 2008), but so far, no Early Triassic assem-blages have been documented from South Tibet. The Niti area innorthern India, is the only nearby locality from where Permian andTriassic palynofloras have been described. There, the poor preserva-tion of brown to black sporomorphs allowed for a qualitative analy-sis and the differentiation of Late Permian and Early Triassicpalynomorph assemblages (Tiwari et al., 1996). Late Permian assem-blages are marked by diverse gymnosperm pollen such as Sulcatisporites(Scheuringipollenites), Striatopodocarpites, Klausipollenites, Cordaitina,Faunipollenites (Protohaploxypinus), Alisporites and several typical Indiantaxa such as Satsangisaccites, Crescentipollenites, and Verticipollenites.Spores are rare and include Horriditriletes, Verrucosisporites, Leiotriletes,and Lundbladispora. Spore assemblage changes significantly near thePermian–Triassic boundary Cyathidites, Densoisporites, Kraeuselisporites,andConvolutispora appear in Early Triassic assemblages,while Leiotriletesand Verrucosisporites disappear (Tiwari et al., 1996).

Here Early Triassic palynofloras from the Tulong area in SouthTibet are described and illustrated for the first time that allows recon-struction and timing of the recovery of Early Triassic gymnospermson the subtropical North Indian Margin. The studied palynoflorashows a distinct floral change from the Smithian to the Spathianreflecting the recovery of gymnosperms in this region prior to thegymnosperm recovery in Central Europe as previously proposed(Looy et al., 1999).

2. Palaeogeography and lithology of the study site

During the Early Triassic the Tulong area was located about 40°Son the southern Tethyan shelf. Together with other sections such asSpiti in North India and the Salt Range in Pakistan, the Tulong arearepresents an important Lower Triassic sedimentary archive of theNorth Indian Margin of Gondwana (Fig. 1a) (Ogg and von Rad, 1994).

Palynological samples have been collected from the four sectionsTulong (Tu), Nazapuo (Na), Tong La West A (TWA), and Tong La WestB (TWB) (Fig. 1b). These sections have been combined in the compositeLower Triassic section of the Tulong area (Brühwiler et al., 2009). De-tailed sedimentological, ammonoid and conodont biostratigraphic, aswell as carbon isotope data were presented by Brühwiler et al. (2009).The sedimentary succession spans the time interval between the LatePermian and the early Middle Triassic. The Upper Permian dark shales

with phosphoritic nodules (Nimaluoshenza Member) resemble theKuling Shales as described from Spiti (Brühwiler et al., 2009). TheUpper Permian is unconformably overlain by the Lower TriassicTulong Formation. The six lithological units of Early to Middle Tri-assic age are characterised either by siliciclastic dominated sedi-ments (Units II, IV, Figs. 2, 3) or by a predominance of, for themost part, fossil-rich carbonate deposits (Units I, III, V, and VI).

3. Methods

A total of 29 fine-grained siliciclastic samples have been cleaned,crushed and weighed (13–18 g) and subsequently treated with hydro-chloric and hydrofluoric acid according to standard palynological prep-aration techniques (Traverse, 2007). Oxidation was performed usingSchulze's reagent (Traverse, 2007). Some samples have been first oxi-dised with nitric acid and subsequently with Schulze's reagent. The res-idues were sieved over an 11 μmmesh screen. For quantitative analysisa minimum of 250 spores and pollen per sample were counted fromstrew mounts. For qualitative data, the slides have been subsequentlyscreened for rare elements. 13 out of 29 samples were productive. Afew samples, marked as virtually barren in Fig. 3, contained poorly pre-served and undeterminable remains of palynomorphs.

4. Results

4.1. Preservation and composition of the particulate organic matter

The depositional setting of the Tulong Formation on the shelf isreflected in the particulate organic matter (POM) composition bythe mixture of marine palynomorphs with a significant contributionof terrestrial organic particles derived from the NIM, which accountfor 60 to 100% of the assemblages. Terrestrial phytoclasts are mostlyopaque; on average translucent phytoclasts amount to 15% of thePOM content. Particles of marine origin are represented by acritarchs,which occur in variable numbers, reaching up to 48% of the POM as-semblage (Fig. 2).

Palynomorphs are dark brown to almost opaque indicating avalue of 6–7 on the thermal alteration scale (TAS) of Batten(1996), which corresponds to a temperature exposure between170 and 200 °C. Amorphous organic matter (AOM), which hasbeen observed in greater amount in sample TWB3-P, is heavily de-graded and black in colour.

a b

Fig. 1. a) Reconstructed palaeogeographic position of the studied site, modified after Smith et al. (1994) and Ogg and von Rad (1994); b) Geological sketch map (modified afterBurg, 1983 and Brühwiler et al., 2009) Tu: section near the village of Tulong; Na: Nazapuo section; TWA: Tong La West A section; TWB: Tong La West B section.

13E. Schneebeli-Hermann et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 339–341 (2012) 12–24

Author's personal copy

4.2. Palynology

The sporomorphs from the Lower Triassic Tulong Formation haveonly been subjected to minor mechanical disintegration whichallowed for a qualitative as well as a quantitative analysis of thesamples. Two different palynofloras are distinguished, a Smithian

palynoflora and a Spathian one (Fig. 3). All identified taxa are listedin Appendix 1.

In the Smithian palynoflora sporomorphs account for 33% to 69%of the total palynomorph assemblage (Fig. 3). The terrestrial palyno-flora is dominated by Densoisporites spp. (including D. playfordi) andLundbladispora spp. (including L. brevicula and L. obsoleta) with rare

Fig. 2. Particulate organic matter content of the composite Tulong section. Ammonoid biostratigraphy and simplified lithology after Brühwiler et al. (2009, 2010). See Fig. 3 forabbreviations of ammonoids. N. Mmb. = Nimaluoshenza Member.

14 E. Schneebeli-Hermann et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 339–341 (2012) 12–24

Author's personal copy

Fig.

3.Re

lative

abun

danc

eof

sporom

orph

taxa

atTu

long

andratios

ofterrestrialtomarinepa

lyno

morph

s.Ammon

oidbiostratigraph

y,simplified

litho

logy

,and

carbon

isotop

esafterBrüh

wile

ret

al.(20

09,2

010)

.Kashm

irites

sp.ind

et.h

asbe

enfoun

das

floa

tin

theup

perpa

rtof

UnitIIindicating

anea

rlySm

ithian

age(B

rühw

ileret

al.,20

10).N.M

mb.

=Nim

aluo

shen

zaMem

ber.

15E. Schneebeli-Hermann et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 339–341 (2012) 12–24

Author's personal copy

occurrences of Aratrisporites spp. (A. scabratus). The poor preservationof some cavate trilete spores made the assignment to either of thementioned genera impossible. Bisaccate pollen grains (includingLunatisporites spp.) are aminor component of the Smithian assemblages.

The dominance of lycopod spores (with Densoisporites spp.,Lundbladispora spp., including L. brevicula and L. obsoleta) and thepresence of Lunatisporites spp. are similar to the assemblages ofthe PTr 2 Zone in Pakistan (Hermann et al., 2012b) (Fig. 4). Highabundances of Micrhystridium and Veryhachium are also a commonfeature of Smithian assemblages from Tulong and Pakistan (Sarjeant,1973; Hermann et al., 2012b). The Indian Klausipollenites schaubergeriAssemblage (Tiwari and Tripathi, 1992) ismarked bydiverse and cavatecingulate–zonate spores occurring together with taeniate bisaccate pol-len resembling the composition of assemblages of PTr 2.Marker speciesin the K. schaubergeri Assemblage are L. pellucidus and L. brevicula,which are also present in the Smithian Assemblage of Tibet (Fig. 4).The first stratigraphic occurrence ofAratrisporites spp. and the increased

abundance of taeniate bisaccate pollen compared to underlying assem-blages are characteristic features of the East Australian APT 102 Zone(Price, 1997) and the Protohaploxypinus samoilovichii Zone (Foster,1982; Helby et al., 1987). APT 102 Zone is overlain by the APT 2 Zone;its base is defined by the FO of Aratrisporites wollariensis (Price, 1997).APT 102 and the basal APT 2 correspond to the Protohaploxypinussamoilovichii Zone (Foster, 1982; Helby et al., 1987; Price, 1997).Aratisporites spp. and taeniate bisaccate pollen are not very abundantin the Smithian assemblage of Tibet but occur regularly which suggestsa correlation with APT 102 and Protohaploxypinus samoilovichii Zone inE-Australia, respectively. TheKraeuselisporites saeptatus Zone inWesternAustralia is marked by lycopod spores (Lundbladispora, Densoisporites,and Kraeuselisporites) and Lunatisporites together with high abundancesof acritarchs (Balme, 1963; Dolby and Balme, 1976). However, in Tibetthe first occurrence of Aratrisporites wollariensis has been documentedin the basal Spathian only whereas A. wollariensis is documented in thebasal Protohaploxypinus samoilovichii Zone (and corresponding basal

Fig. 4. Correlation of the Smithian and Spathian palynological assemblages from Tibet with the palynostratigrapic schemes of Pakistan, India, and Australia.

Plate I. Illustration of main floral elements. Taxon name is followed by the PIMUZ repository number, the sample number (bold), slide number (brackets) and stage coordinates foran Olympus BX 51 microscope. Scale bar is 20 μm on all photomicrographs.1. Inaperturopollenites sp., A/VI 4, Tu-P4 (b), 11.6/127.22. Alisporites tenuicorpus, A/VI 4, Tu-P7 (b), 6.1/116.43. Alisporites tenuicorpus A/VI 4, Tu-P4 (b), 20.4/119.84. ?monosaccate/ ?bisaccate pollen grain, A/VI 4, Tu-P5 (b), 19.5/147.35. ?Bhardwajispora sp., A/VI 4, Tu-P5 (b)m, 3.5/138.96. ?Striatopodocarpites/?Platysaccus, A/VI 4, Tu-P3 (a),10.8/120.17. Sulcatisporites sp., A/VI 4, Tu-P8 (b), 8.6/146.48. Chordasporites sp., A/VI 4, Tu-P5 (b), 11.7/146.39. Trisaccate pollen grain, A/VI 4, Tu-P3 (a), 11.7/129.510. Alisporites landianus?, A/VI 4, Tu-P7 (b), 20.0/117.611. Falcisporites sp., A/VI 4, Tu-P4 (b), 18.7/120.212. Platysaccus sp., A/VI 4, Tu-P5 (b), 21.4/128.013. Lunatisporites pellucidus, A/VI 4, Tu-P4 (b), 20.5/123.414. Striatopodocarpites sp., A/VI 4 Tu-P4 (b), 20.8/142.315. Ephedripites sp., A/VI 4, Tu-P2 (a), 18.7/120.216. ?Striatoabieites sp., A/VI 4, Tu-P3 (a), 9.6/136.917. Monosaccate pollen grain, A/VI 4, Tu-P4 (b), 9.6/136.918. Monosaccate pollen grain, A/VI 4, Tu-P4 (b), 9.6/136.919. Protohaploxypinus sp., A/VI 4, Tu-P3 (a), 9.4/125.0

16 E. Schneebeli-Hermann et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 339–341 (2012) 12–24

Author's personal copy

APT2), which are of Dienerian–Smithian age (Foster, 1982). Thereforethe position of the APT 102-APT 2 boundary with respect to the Tibetansamples is unclear.

In the Spathian palynoflora sporomorphs account for between 54%and 76% of the total palynomorph content, but in contrast to theSmithian palynoflora, the Spathian one is dominated by bisaccate pol-len. Unfortunately the corpi of numerous pollen grains are opaque so thatit is impossible to differentiate between taeniate and non-taeniate forms(e.g. ?Striatopodocarpites/?Platysaccus Plate I, 6). However, taxa thatcould be determined to genus or species level include Lunatisporitespellucidus, L. noviaulensis, ?Crustaesporites sp., Alisporites spp. (including

A. landianus, A. tenuicorpus), Chordasporites sp., Falcisporites spp. (includ-ing F. australis), Platysaccus spp., Potonieisporites sp., ?Bhardwajispora sp.,and ?Florinites sp. Potonieisporites and Florinites are typical Palaeozoicgenera. Due to the over-all high thermal maturity of the samples itis difficult to judge whether these forms are in situ or reworked.Spores are more diverse than in the Smithian palynoflora. Especiallythe Aratrisporites group diversifies with first occurrences of A. scabratus,A. wollariensis, A. tenuispinosus, and an intermediate morphotype A.wollariensis-tenuispinosus (de Jersey, 1982), as well as rare A. paenulatus.

The regular and abundant occurrence of Aratrisporites spp. andFalcisporites spp. is a common characteristic of the Spathian

17E. Schneebeli-Hermann et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 339–341 (2012) 12–24

Author's personal copy

assemblage of Tibet, PTr 5 in Pakistan and the E-Australian zones APT212 (Price, 1997) and Aratrisporites tenuispinosus Zone (Helby et al.,1987), as well as the Tigrisporites playfordii (now Triplexisporitesplayfordii) Assemblage of Western Australia (Dolby and Balme,1976). The correlation of the Spathian assemblages with Indian paly-nostratigraphic schemes is ambiguous. The base of the Playfordiasporacancellosa Assemblage (Tiwari and Tripathi, 1992) is defined by thecommon occurrence of Lunatisporites pellucidus, Lundbladispora andDensoisporites. Decreasing abundance of taeniate bisaccate pollen isdocumented within this zone, which is also observed in Pakistan fromPTr 4 to PTr 5. However, for the Indian Playfordiaspora cancellosaAssem-blage an acme of Lunatisporites is mentioned (Tiwari and Tripathi,1992), which would rather correspond to PTr 4 (Fig. 4) (Hermann etal., 2012b).

Marine palynomorphs occur throughout the succession and includeMicrhystridium spp., Veryhachium spp., Peltacystia sp., Cymatiosphaeraspp., foraminiferal test linings (Fig. 4), and rare occurrences ofDorsennidium spp. Micrhystridium spp. and Veryhachium spp. arethe most abundant marine palynomorphs (Fig. 5). However, theirrelative abundances change throughout the section. Veryhachiumis very abundant in the topmost Smithian sample and towardsthe top of the Spathian productive samples. Foraminifera test lin-ings have been observed in almost every palynological sample,particularly in TWB8m-P and the basal Spathian samples. In thelatter samples Cymatiosphaera spp. occurs regularly (Fig. 5). Scole-codonts have been observed as accessory components. In sampleTWB8m-P, the dominant marine palynomorph is an acritarch,which is atypical for Triassic assemblages (accounting for 70% ofthe marine palynomorph assemblage). Preliminarily, these acri-tarchs have been assigned to the genus Tongzia spp., based onthe morphology of the processes, which are bifurcated (Plate II,28). The processes show a distal weak enlargement of the processtrunk from which the arched pinnae arise. With a vesicle diameterof 22–29 μm the specimens from Tibet are smaller than the genusholotype T. meitana (vesicle diameter of 44 to 56 μm) (Li, 1987).Smaller acritarchs assigned to Tongzia have been reported as Tong-zia sp. 1 (Yin et al., 1998; vesicle size: 30.2–49.9 μm). So far this

genus is known only from the Ordovician (Arenig; Li, 1987). Better pre-servedmaterial will be necessary to confirm or revise the assignment ofthese acritarch specimens to Tongzia.

5. Implications for marine palaeoenvironment, palaeoclimate, andfloral recovery

5.1. Marine palaeoenvironment

Variations in the composition of the POM are known to mirrorchanges in the depositional environment (Tyson, 1995). The compo-sition of the POM in the Smithian interval of the Lower Triassic TulongFormation shows similarities with the Lower Triassic Mianwali For-mation of Pakistan (Hermann et al., 2011b). Due to the heavy degrada-tion of amorphous organic matter in the Upper Permian samples apreservation bias with respect to the marine/terrestrial ratio of the POMcannot be excluded for the entire succession. However, a strong marineinfluence is suggested by the high relative abundance of acritarchs inthe early Smithian POM composition, followed by a shoaling trend to-wards the Smithian–Spathian boundary (Fig. 2). This shoaling trend isreflected in the increasing relative abundance of terrestrial organic parti-cles such as phytoclasts and sporomorphs. The same trend of increasingterrestrial derived particles in the POMcomposition suggesting a shoalingof the depositional environment has been observed in the Mianwali For-mation in the same stratigraphic interval (Hermann et al., 2011b). Simi-larities between the lithological successions of the Tulong Formation,the Mianwali Formation, and the Mikin Formation in Spiti have beennoted earlier (Brühwiler et al., 2009).

The occurrence of the Ordovician acritarch genus Tongzia spp. inthe early Smithian of the Tulong area is cryptic. Acritarch diversitydeclined during the late Devonian and remained low during latePalaeozoic and Early Triassic times. This “Late Palaeozoic phyto-plankton blackout” has been proposed to be marked by low phyto-plankton productivity and diversity with occasional blooms of afew acritarch species (Riegel, 2008). Early Triassic acritarch assem-blages are usually poor in diversity and consist essentially of the gen-era Micrhystridium, Veryhachium, and Baltisphaeridium (e.g. Payne

Plate II. Illustration of main floral elements. Taxon name is followed by the PIMUZ repository number, the sample number (bold), slide number (brackets) and stage coordinates foran Olympus BX 51 microscope. Scale bar is 20 μm on all photomicrographs.1. ?Punctatosporites/Laevigatosporites sp. A/VI 4, Tu-P5 (b), 7.6/143.52. Aratrisporites scabratus, A/VI 4, Tu-P7 (b), 10.5/135.33. Aratrisporites wollariensis, A/VI 4, Tu-P2 (a), 6.3/145.84. Aratrisporites tenuispinosus A/VI 4, Tu-P7 (b), 10.1/132.95. Aratrisporites tenuispinosus, A/VI 4, Tu-P7 (b), 8.5/143.96. Aratrisporites paenulatus, A/VI 4, Tu-P3 (a), 9.5/112.87. Punctatisporites sp., A/VI 4, Tu-P8 (b), 10.5/146.78. Leiotriletes sp., A/VI 4, Tu-P5 (b), 10.5/146.79. Annulispora/Limatulasporites, A/VI 5, TWB51-P (a), 15.3/134.510. Calamospora tener, A/VI 5, TWB51-P (a), 9.8/124.611. Osmundacidites sp., A/VI 4, Tu-P3 (a), 13.3/123.512. Densoisporites sp. A/VI 5, TWB50-P (a), 6.7/119.013. Lundbladispora obsoleta, A/VI 5, TWB53-P (a), 12.6/129.214. Exospore Playfordiaspora crenulata, A/VI 4, Tu-P3 (a), 10.8/127.015. Lundbladispora brevicula, A/VI 5, TWB53-P (a), 10.2/121.316. Lundbladispora brevicula, A/VI 5 TWB50-P (a), 12.5/122.317. foraminiferal test lining, A/VI 4, Tu-P7 (b), 9.9/112.3;18. Scolecodont A/VI 4, Tu-P3 (b), 10.7/113.519. ?Peltacystia sp., A/VI 5, TWB51-P (a), 11.7/149.720. Micrhystridium sp., A/VI 4, Tu-P7 (b), 10.0/145.921. Scolecodont, A/VI 4, Tu-P4 (b), 8.5/108.722. Veryhachium sp., A/VI 4, Tu-P4 (b), 17.2/149.423. Dorsennidium sp. A/VI 4, Tu-P5 (a), 12.9/111.824. Dorsennidium sp. A/VI 4, Tu-P5 (b), 12.3/136.425. Dorsennidium sp., A/VI 4, Tu-P5 (b),19.5/147.326. Micrhystridium sp., A/VI 4, Tu-P4 (b),12.0/130.427. Tongzia sp., A/VI 4, TWB8m (a), 20.1/112.428. Tongzia sp., A/VI 4, TWB8m (b), 9.5/26.0, showing bifurcation of processes29. Tongzia sp., A/VI 4, TWB8m (a), 16.0/127.430. Cymatiosphaera sp., A/VI 4, Tu-P4 (b), 16.3/112.831. Cymatiosphaera sp., A/VI 4, Tu-P4 (b), 16.0/121.8

18 E. Schneebeli-Hermann et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 339–341 (2012) 12–24

Author's personal copy

19E. Schneebeli-Hermann et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 339–341 (2012) 12–24

Author's personal copy

and van de Schootbrugge, 2007). At Tulong acritarchs are present inmoderate to high numbers (25–75% of palynomorph assemblage)throughout the studied interval and comprise besides Micrhystridiumspp. and Veryhachium spp. also Peltacystia sp., Cymatiosphaera spp.,Dorsennidium spp. and Tongzia spp. in one sample. To explain the abun-dant occurrence of Tongzia spp. reworking of Ordovician sediments can-not be completely excluded. However, the sample material has beenchecked for extraclasts, which would indicate reworking and could ex-plain the Ordovician acritarch genus within an otherwise Early Triassicassemblage, but there is no sedimentological evidence for reworking ona macroscopical scale. The sample consists of homogenous siltstone,and no other typical Ordovician palynomorphs have been found. Fur-thermore, the preservation of Tongzia spp. does not differ from the co-occurringMicrhystridium spp. and Veryhachium spp. and the abundanceof Tongzia spp. in a single sample (TWB8m-P) is striking. It would implya source sediment with a monogeneric Ordovician acritarch assem-blage. However, compared to Early Triassic assemblages Ordovicianpalynomorph assemblages are known to be highly diverse (e.g.Strother, 1996).

5.2. Palaeoclimate

Pteridophytes are generally known to proliferate predominantly inhumid environments (e.g. Van Konijnenburg-Van Cittert, 2002), whereasgymnosperms growpreferably under drier conditions (e.g. Kustatscher etal., 2010). For the early Mesozoic, the ratio between these two groups,expressed in the spore/pollen ratios have been used to describe relativechanges of humidity (e.g. Hochuli et al., 2010a). At Tulong the palynolog-ical assemblages shift from lycopod spore-dominated humid conditionsin the Smithian to gymnosperm-dominated drier conditions in theSpathian. In Pakistan a similar change has also been documented tooccur across the upper Smithian Wasatchites distractus beds towards theSpathian (Hermann et al., 2012a). In Australia the Tigrisporites playfordiiZone and the Aratrisporites tenuicorpus Zone are dominated by non-taeniate bisaccate pollen (mostly Falcisporites australis) compared to theunderlying spore-dominated assemblages (Dolby and Balme, 1976;Helby et al., 1987). Ammonoids of Smithian or Spathian age have notbeen documented in Australia; therefore the correlation of the assem-blage change in Australia is based only on palynology (Fig. 4). After theend-Permian mass extinction, ammonoids and conodonts recoveredvery quickly, whereas benthic organisms were initially thought to haverecovered very slowly (Erwin, 1996). Ammonoids and conodonts didnot recover continuously, but suffered from extinctions in the EarlyTriassic, of which the late Smithian one was the most severe. This extinc-tion event, about 2 Ma after the end-Permianmass extinction, is reflectedin the Wasatchites beds. They are marked by cosmopolitan ammonoidand conodont fauna (Brayard et al., 2006; Orchard, 2007; Goudemand,personal observation). The Norwegian Smithian–Spathian succession isthe only ammonoid-calibrated palynological record in the Northernhemisphere so far. There the quantitative palynological data show a sim-ilar change from spore-dominated Smithian assemblages below theWasatchites beds to bisaccate pollen-dominated Spathian assemblagesabove theWasatchites beds (Galfetti et al., 2007b). A similar composition-al change has been documented in the quantitative palynological data inthe continental Buntsandstein series of Western Poland. While theassemblages of the Middle Buntsandstein are dominated by spores(Densoisporites nejburgii Zone, probably lower Scythian), bisaccate pol-len are dominant in the Voltziaceaesporites heteromorpha Zone (proba-bly Spathian) of the Upper Buntsandstein of Orłowska-Zwolińska(1984). Age determinations of these assemblages are based on cor-relation with other palynological records and only tentative(Orłowska-Zwolińska, 1984). The climate change as indicated bythe sporomorph record from Tibet has been recorded from differ-ent climatic zones and latitudes. Although, the middle Smithian,just below the Wasatchites distractus beds, has not been sampledbecause of the unsuitable lithology in Tibet, the distinct

palynofloral change from the Smithian assemblages to theSpathian assemblages is apparent and confirms the global signifi-cance of the climate change close to the late Smithian ammonoidand conodont extinction event (Fig. 3).

5.3. Floral recovery

After the floral turnover of the Late Permian, lycopods thrived inwidespread areas from 70°N to low palaeolatitudes (e.g. Looy et al.,1999; Krassilov and Karasev, 2009) and were the dominant constitu-ent of the Early Triassic vegetation across floral and climatic provinces(Retallack, 1995; Foster et al., 1997). The abundance of lycopods hasbeen interpreted to represent the pioneer vegetation after destruc-tion of terrestrial ecosystems (Looy et al., 1999; Grauvogel-Stammand Ash, 2005). Another explanation of the abundance of pterido-phytes during times of major environmental perturbations is basedon the plant physiological features of pteridophytes. Pteridophytespossess an array of mechanisms to cope with adverse environmentalconditions (Page, 2002). Hence, it has been suggested that the domi-nance of pteridophytes during short time intervals in Earth history(so-called spore-spikes) reflects adaptations of plant communitiesto environments inhospitable for other plants (van de Schootbruggeet al., 2009; Hochuli et al., 2010a; Hermann et al., 2011a).

In East Greenland (Stemmerik et al., 2001) and Norway (Hochuli etal., 2010a), the end-Permian floral turnover is marked by a prominentspore spike that occurs in the uppermost Permian sediments. InNorway, this spore spike corresponds to a short interval dominated bylycopod spores occurring during the negative carbon isotope excursion,and gymnosperms recovered immediately after this spore spike (Fig. 6).Correlation of the Norwegian sectionwith the geochronologically dated(Mundil et al., 2001, 2004) Permian–Triassic stratotype section inMeishan (South China, Yin et al., 2001) suggests that the change fromlycopod dominated flora to recovered gymnosperm flora occurredwithin some 10 ka (Hochuli et al., 2010a), prior to the Permian–Triassicboundary as defined by the first occurrence of the conodont speciesHindeodus parvus (Yin et al., 2001).

The Lower Triassic successions in the Salt Range and SurgharRange (Pakistan) are exceptional for the NIM. The well preservedpalynofloral succession is combined with a detailed ammonoidbiostratigraphy. There the stratigraphy of the floral turnover nearthe Permian–Triassic boundary is less clear compared to Norwayand East Greenland due to hiatuses in the latest Permian and dia-chronism of the boundaries between Permian and Triassic formations(Hermann et al., 2011b). However, lycopod abundance increase fromthe Late Permian up-section towards the Early Triassic and high lyco-pod concentrations are reached in the Dienerian. Assemblages ofearly Smithian age suggest a return of more diverse floras with mod-erate numbers of gymnosperms. This diversification was interruptedonce more by a pronounced spore spike in the middle Smithian, butfrom the late Smithian onward gymnosperms re-established progres-sively (Hermann et al., 2011a).

In the Tulong area, the abundance of cavate trilete spores in theSmithian assemblage indicates that lycopods were the dominantcomponent of the vegetation during this time interval. As in early–middle Smithian assemblages of Pakistan gymnosperms (conifersand pteridosperms), represented by bisaccate pollen, played a subor-dinate role. The floral composition had changed significantly bySpathian times. The Spathian shows proliferating gymnosperms andthe abundance of lycopod spores is reduced. Ferns, represented byGranulatisporites, Osmundacidites, and Convolutispora are new compo-nents of the vegetation. Thus, in contrast to the long delay of resur-gence of the Central European conifer forests (4–5 Ma, Looy et al.,1999), the vegetation on the NIM is marked by proliferating conifersand pteridosperms already ca. 2 Ma after the end-Permian floral turn-over (dating after Ovtcharova et al., 2006; Galfetti et al., 2007a). InAustralia, the abundance of Falcisporites spp. in the Tigrisporites

20 E. Schneebeli-Hermann et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 339–341 (2012) 12–24

Author's personal copy

playfordii Zone (Western Australia) and the Aratrisporites tenuicorpusZone (E-Australia) indicates the proliferation of the seed fernDicroidium.Both assemblages have been correlatedwith Spathian assemblages fromTibet and Pakistan (see Section 4.2.). Biomarker studies on the Lower Tri-assic succession of tropical Chaohu area (SouthChina) indicate also a clearchange from herbaceous lycopods and bryophytes in the Griesbachian–Smithian, and the dominance of woody conifers in the Spathian (Saitoet al., 2011). In mid latitudes of the northern hemisphere gymnospermsbecame prominent again in early Spathian palynofloral assemblages(e.g. Barents Seas area, Svalis Dome: Hochuli and Vigran, 2010).

In several regions gymnosperms recovered early in the Spathian(southern subtropics: Pakistan, Tibet, Australia the temperate zoneof the northern hemispheres: Norway, and the tropics of SouthChina) (Fig. 6) compared with the apparently late recovery in the

Central European tropics. What favoured the early recovery in theseregions?

Climate models have suggested a strong monsoonal circulation forthe Triassic period predicting summer rainfall maxima on the NIMand all-year humid conditions for the northern mid-latitudes, whileyear-round arid conditions were predicted for the tropics except forthe eastern coast of Pangea and the eastern Tethys (i.e. South China)(e.g. Kutzbach and Gallimore, 1989; Kutzbach and Ziegler, 1993).With-in this basic climatic framework, there is growing evidence that envi-ronmental perturbations had a determinant impact on the EarlyTriassic recovery patterns of marine faunas (e.g. Brayard et al., 2011).Evidence for recurrent environmental changes during the Early Triassicis the multiple and large scale perturbations of the global carbon cycle(Galfetti et al., 2007a; Whiteside and Ward, 2011). Ecosystems after

Fig. 5. Relative abundance of marine palynomorphs. Note the different scales in the columns Cymatiosphaera, Peltacystia, and foraminifera test lining. See Figs. 2 and 3 for lithologicallegend and abbreviations.

21E. Schneebeli-Hermann et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 339–341 (2012) 12–24

Author's personal copy

mass extinctions are sensitive to minor environmental changes, whichcould be intrinsic reasons, climate changes or volcanic eruption causingtrophic collapses and chaotic behaviour of the carbon cycle (Whitesideand Ward, 2011). A possible area of recurrent volcanic activity duringthe Early Triassic is the Siberian Traps large igneous province (Payneand Kump, 2007). During the emplacement of the Siberian Traps notonly the greenhouse gas CO2 but also SO2 and halocarbons were re-leased, which besides climatic impact, had other environmental conse-quences such as acid rain or ozone layer depletion. (Svensen et al.,2009; van de Schootbrugge et al., 2009). The Early Triassic carbon iso-tope record has been used as an indicator for environmental stress caus-ing extinction and delayed recovery (Payne et al., 2004; Payne andKump, 2007). Compared to the lower part of the Early Triassic the fre-quency of carbon isotope fluctuations slowed during the Spathian.Whiteside and Ward (2011) interpreted intervals of stable carbon iso-tope values during the Triassic to represent times of stable environmentsand biotic recovery.

The nearly cosmopolitan distribution of Pleuromeia, a prominentEarly Triassic lycopod indicates high CO2 concentrations (Krassilovand Karasev, 2009). Pleuromeiacean have been adapted to varioushabitats including saline coastal environments (Retallack, 1975), flu-vial environments or desert oases (e.g. Grauvogel-Stamm, 1999), orareas with seasonally wet climate (Cantrill and Webb, 1998). In Cen-tral Europe, Pleuromeiacean-dominated vegetation persisted untilthe Middle Triassic mirroring the long recovery time that has beenproposed for marine biota (e.g. Erwin, 1996). The Early Triassic vege-tation in relatively humid areas (northern temperate zones, southernsubtropics, South Chinese tropics) seems to have benefited first fromthe improved and more stable environmental conditions in theSpathian, whereas vegetation growing under the climatic conditionsof the semi-arid/arid tropics might have remained more vulnerable.However, for the marine realm, recent data show that high diversitybenthic communities established early (Griesbachian ichnologicaldata, Werfen Formation, Italy: Hofmann et al., 2011; mollusc fauna,South China: Hautmann et al., 2011). Additionally, the Early Triassic

metazoan reef gap has to be considered as an artefact of preservationbias, since metazoan-rich reefs have been described to occur about1.5 million years after the end-Permian extinction (Brayard et al.,2011). And regarding the nekton, ammonoids and conodonts thrivedshortly after the end-Permian extinction (Brayard et al., 2006; Orchard,2007). Since many European Upper Permian to Lower Triassic succes-sions are non-marine or themarine biostratigraphic resolution is insuffi-cient (e.g. Utting and Piasecki, 1995), early changes in the vegetation ofthe tropical continental areas might have been missed in a similar way,most probably due to preservation bias, incomplete archives or uncertainage assignment (e.g. Orłowska-Zwolińska, 1984).

6. Conclusion

The thermally altered but fairly well preserved palynological as-semblages from Tulong (South Tibet) allow the description of twodiscrete palynological assemblages: (1) a Smithian lycopod sporedominated flora (samples TWB8m-P to Na12/13-P2 to in Fig. 3) and(2) a gymnosperm pollen dominated flora of Spathian age (samplesTu-P2 to Tu-P8 in Fig. 3). The documented shift from lycopod-dominated vegetation to gymnosperm-dominated vegetation nearthe Smithian–Spathian boundary in the Tulong area (South Tibet),and similar trends in successions in Pakistan, Australia, Norway, andSouth China suggest that in these areas the Early Triassic recoveryof forests started about 2 Ma after the end-Permian. This floral shiftrepresents the third and most successful attempt to restore gymno-sperm vegetation after the early floral recoveries in the latest Permianof Norway and the early Smithian of Pakistan (Fig. 6). Environmentalamelioration probably favoured an early recovery in the relativelyhumid regions of the southern subtropics, the northern mid latitudes,and South China. In Central Europe, environmental conditions wereless favourable for the recovery of gymnosperms during the Early Trias-sic. However, biostratigraphic uncertainties may have hampered thediscovery of a Spathian gymnosperm recovery as well. The describedpalynofloral patterns coincide with and are probably related to the

Fig. 6. Comparison of the floral recovery in Central Europe (modified after Looy et al., 1999) and floral recovery pulses as recorded in Lower Triassic successions from the northernmid latitudes (Norway) and the southern subtropics (Pakistan, Tibet). U/Pb ages after 1) Galfetti et al., 2007a; 2) Mundil et al., 2004; 3) Ovtcharova et al., 2006. Schematic bulkorganic carbon isotopes after Hermann et al., 2010 (latest Permian, Norway) and Hermann et al., 2011b, (Early Triassic, Pakistan).

22 E. Schneebeli-Hermann et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 339–341 (2012) 12–24

Author's personal copy

changes in the carbon isotope record suggesting that the floral recov-ery dynamics were linked to the environmental perturbations. Thepalynological succession in Tulong demonstrates that the end-Permian floral turnover was followed by several attempts of recov-ery of gymnosperm vegetation, and provides further evidence forthe existence of gymnosperm dominated floras prior to the MiddleTriassic.

Acknowledgements

We acknowledge financial support from the Swiss National Sci-ence Foundation project 200020‐113554 (to H. B.) and PBZHP2-135955 (to E. S.-H.). We also thank Thomas Servais for discussionon acritarchs. For insightful comments that helped to improve an ear-lier version of this paper significantly, we thank John Backhouse andan anonymous reviewer.

Appendix 1

List of identified palynomorphs:

Spores

Aratrisporites paenulatus Playford & Dettmann 1965Aratrisporites scabratus Klaus 1960Aratrisporites spp. (Leschik) Playford & DettmannAratrisporites tenuispinosus Playford 1965Aratrisporites wollariensis Helby 1967Aratrisporites wollariensis-tenuispinosus sensu de Jersey, 1982Calamospora landiana Balme 1970Calamospora tener (Leschik) de Jersey 1962Cavate spores undifferentiatedConcavisporites sp. Pflug in Thomson & Pflug 1953Convolutispora sp. 1 sensu Hermann et al., 2012bDensoisporites nejburgii (Schulz) Balme 1970Densoisporites playfordi (Balme) Dettmann 1963Densoisporites spp. (Weyland & Krieger) Dettmann 1963Endosporites papillatus Jansonius 1962Exospore of Playfordiaspora crenulataGranulatisporites spp. (Ibrahim) Schopf, Wilson & Bentall 1944Kraeuselisporites spp. (Leschik) Jansonius 1962Leiotriletes sp. (Naumova) ex Potonié & Kremp 1954Lundbladispora brevicula Balme, 1963Lundbladispora obsoleta Balme 1970Lundbladispora spp. (Balme) Playford 1965Osmundacidites spp. Couper 1953Punctatisporites spp. (Ibrahim) Potonié & Kremp 1954Undifferentiated sporesUndifferentiated monolete sporesVerrucosisporites spp. (Ibrahim) Smith & Butterworth 1967

Pollen

Alisporites landianus Balme 1970Alisporites spp. (Daugherty) Jansonius 1971Alisporites tenuicorpus Balme 1970?Bhardwajispora sp. Jansonius 1962Chordasporites sp. Klaus 1960?Crustaesporites Leschik 1956Ephedripites sp. (Bolkhovitina) ex Potonié 1985Falcisporites australis (de Jersey) Steiner 1981Falcisporites spp. (Leschik) Klaus 1963

?Florinites sp. Schopf, Wilson & Bentall 1944Inaperturopollenites sp. (Thomson & Pflug) Potonié 1958Lunatisporites noviaulensis (Leschik) Foster 1979Lunatisporites pellucidus Goubin (Helby 1972)Lunatisporites spp. Leschik 1956Monosaccate pollen grainPlatysaccus spp. Naumova ex Potonié & Klaus 1954Protohaploxypinus sp. (Samoilovich) Hart 1964Striatoabieites sp. Sedova 1956Striatopodocarpites sp. (Zoricheva & Sedova ex Sedova) Hart 1964Sulcatisporites sp. (Leschik) Nilsson 1958Undifferentiated bisaccate pollenUndifferentiated non taeniate bisaccate pollenUndifferentiated taeniate bisaccate pollen

Aquatic palynomorphs

Cymatiosphaera spp. Wetzel ex Deflandre 1954Foraminiferal test liningsMicrhystridium spp. (Deflandre) Sarjeant 1967Peltacystia venosa Balme & Segroves 1966Dorsennidium spp. (Wicander) Sarjeant and Stancliffe 1994Tongzia spp. (Li) Yin, Di Milia & Tongiorgi 1998Veryhachium spp. Deunff ex Downie 1959

References

Balme, B.E., 1963. Plant microfossils from the Lower Triassic of Western Australia.Palaeontology 6, 12–44.

Batten, D.J., 1996. Palynofacies and petroleum potential. In: Jansonius, J., McGregor,D.C. (Eds.), Palynology: Principles and Applications, 3. American Association ofStratigraphic Palynologists Foundation, Dallas, TX, pp. 1065–1084.

Brayard, A., Bucher, H., Escarguel, G., Fluteau, F., Bourquin, S., Galfetti, T., 2006. TheEarly Triassic ammonoid recovery: paleoclimatic significance of diversity gradi-ents. Palaeogeography, Palaeoclimatology, Palaeoecology 239, 374–395.

Brayard, A., Escarguel, G., Bucher, H., Monnet, C., Brühwiler, T., Goudemand, N., Galfetti,T., Guex, J., 2009. Good genes and good luck: ammonoid diversity and the end-Permian mass extinction. Science 325, 1118–1121.

Brayard, A., Vennin, E., Olivier, N., Bylund, K.G., Jenks, J., Stephen, D.A., Bucher, H.,Hofmann, R., Goudemand, N., Escarguel, G., 2011. Transient metazoan reefs in theaftermath of the end-Permian mass extinction. Nature Geoscience 4, 693–697.

Brühwiler, T., Goudemand, N., Galfetti, T., Bucher, H., Baud, A., Ware, D., Hermann, E.,Hochuli, P.A., Martini, R., 2009. The Lower Triassic sedimentary and carbon isotoperecords from Tulong (South Tibet) and their significance for Tethyan palaeoceano-graphy. Sedimentary Geology 222, 314–332.

Brühwiler, T., Bucher, H., Goudemand, N., 2010. Smithian (Early Triassic) ammonoidsfrom Tulong, South Tibet. Geobios 43, 403–431.

Burg, J.P., 1983. Carte géologique du sud du Tibet/Ministère de la Géologie – Pékin(République Populaire de Chine); Contours synth. par J.P. Burg. China. Ministry ofGeology and Mineral Resources, Paris.

Cantrill, D.J., Webb, J.A., 1998. Permineralized pleuromeid lycopsid remains from theEarly Triassic Arcadia Formation, Queensland, Australia. Review of Palaeobotanyand Palynology 102, 189–211.

de Jersey, N.J., 1982. An evolutionary sequence in Aratrisporites miospores from theTriassic of Queensland, Australia. Palaeontology 25, 668–672.

Dolby, J.H., Balme, B.E., 1976. Triassic palynology of the Carnarvon Basin, WesternAustralia. Review of Palaeobotany and Palynology 22, 105–168.

Erwin, D.H., 1996. The mother of mass extinction. Scientific American 1996, 72–78 (July).Forel, M.B., Crasquin, S., Brühwiler, T., Goudemand, N., Bucher, H., Baud, A., Randon, C., 2011.

Ostracod recovery after Permian–Triassic boundarymass-extinction: the south Tibet re-cord. Palaeogeography, Palaeoclimatology, Palaeoecology 308, 160–170.

Foster, C.B., 1982. Spore-pollen assemblages of the Bowen Basin, Queensland (Australia):their relationship to the Permian/Triassic boundary. Review of Palaeobotany andPalynology 36, 165–183.

Foster, C.B., Logan, G.A., Summons, R.E., Gorter, J.D., Edwards, D.S., 1997. Carbon iso-topes, kerogen types and the Permian–Triassic boundary in Australia: implicationsfor exploration. APPEA Journal 37, 472–489.

Galfetti, T., Bucher, H., Ovtcharova, M., Schaltegger, U., Brayard, A., Brühwiler, T.,Goudemand, N., Weissert, H., Hochuli, P.A., Cordey, F., Guodon, K., 2007a. Timingof the Early Triassic carbon cycle perturbations inferred from new U–Pb ages andammonoid biochronozones. Earth and Planetary Science Letters 258, 593–604.

Galfetti, T., Hochuli, P.A., Brayard, A., Bucher, H., Weissert, H., Vigran, J.O., 2007b.Smithian–Spathian boundary event: evidence for global climatic change in thewake of the end-Permian biotic crisis. Geology 35 (4), 291–294.

23E. Schneebeli-Hermann et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 339–341 (2012) 12–24

Author's personal copy

Garzanti, E., Nicora, A., Rettori, R., 1998. Permo–Triassic boundary and lower to middleTriassic in South Tibet. Journal of Asian Earth Sciences 16, 143–157.

Grauvogel-Stamm, L., 1999. Pleuromeia sternberii (Münster) Corda, eine charakterischePflanze des deutschen Buntsandsteins. In: Hauschke, N., Wilde, V. (Eds.), Trias, eineganz andere Welt. Verlag Dr. Friedrich Pfeil, München, pp. 271–282.

Grauvogel-Stamm, L., Ash, S.R., 2005. Recovery of the Triassic land flora from the end-Permian life crisis. Comptes Rendus Palevol 4, 593–608.

Hankel, O., 1991. Early Triassic plantmicrofossils from the Kavee Quarry section of the LowerMariakani Formation, Kenya. Review of Palaeobotany and Palynology 68, 127–145.

Hautmann, M., Bucher, H., Brühwiler, T., Goudemand, N., Kaim, A., Nützel, A., 2011. An un-usually diversemollusc fauna from the earliest Triassic of South China and its implica-tion for benthic recovery after the end-Permian biotic crisis. Geobios 44, 71–85.

Helby, R., Morgan, R., Partridge, A.D., 1987. A palynological zonation of the AustralianMesozoic. In: Jell, P.A. (Ed.), Studies in Australian Mesozoic Palynology, 4. Associa-tion of Australasian Palaeontologists, Sydney, pp. 1–94.

Hermann, E., Hochuli, P.A., Bucher, H., Vigran, J.O., Weissert, H., Bernasconi, S.M., 2010.A close-up view of the Permian–Triassic boundary based on expanded organic car-bon isotope records from Norway (Trøndelag and Finnmark Platform). Global andPlanetary Change 74, 156–167.

Hermann, E., Hochuli, P.A., Bucher, H., Brühwiler, T., Hautmann, M., Ware, D., Roohi, G.,2011a. Terrestrial ecosystems on North Gondwana following the end-Permianmass extinction. Gondwana Research 20, 630–637.

Hermann, E., Hochuli, P.A., Méhay, S., Bucher, H., Brühwiler, T., Hautmann, M., Ware, D.,Roohi, G., ur-Rehman, K., Yaseen, A., 2011b. Organic matter and palaeoenviron-mental signals during the Early Triassic biotic recovery: the Salt Range and SurgharRange records. Sedimentary Geology 234, 19–41.

Hermann, E., Hochuli, P.A., Bucher, H., Roohi, G., 2012a. Early Triassic palynology of the SaltRange and Surghar Range, Pakistan. Review of Palaeobotany and Palynology 169, 61–95.

Hermann, E., Hochuli, P.A., Bucher, H., Brühwiler, T., Hautmann, M., Ware, D., Weissert,H., Roohi, G., Yasseen, A., ur-Rehman, K., 2012b. Climatic oscillations at the onset ofthe Mesozoic inferred from palynological records from the North Indian Margin.Journal of the Geological Society of London 169, 227–237.

Hochuli, P.A., Vigran, J.O., 2010. Climate variations in the Boreal Triassic—inferred frompalynological records from the Barents Sea. Palaeogeography, Palaeoclimatology,Palaeoecology 290, 20–42.

Hochuli, P.A., Collin, J.P., Vigran, J.O., 1989. Triassic biostratigraphy of the Barents Seaarea. In: Collinson, J.D. (Ed.), Correlation in Hydrocarbon Exploration, NorwegianPetroleum Society (NPF). Graham &Trotman Ltd., Norwell, MA, pp. 131–153.

Hochuli, P.A., Hermann, E., Vigran, J.O., Bucher, H., Weissert, H., 2010a. Rapid demiseand recovery of plant ecosystems across the end-Permian extinction event. Globaland Planetary Change 74, 144–155.

Hochuli, P.A., Vigran, J.O., Hermann, E., Bucher, H., 2010b. Multiple climatic changesaround the Permian–Triassic boundary event revealed by an expanded palynolog-ical record frommid-Norway. Geological Society of America Bulletin 122, 884–896.

Hofmann, R., Goudemand, N.,Wasmer,M., Bucher, H., Hautmann,M., 2011. New trace fos-sil evidence for an early recovery signal in the aftermath of the end-Permianmass ex-tinction. Palaeogeography, Palaeoclimatology, Palaeoecology 310, 216–226.

Krassilov, V.A., Karasev, E., 2009. Paleofloristic evidence of climate change near and be-yond the Permian–Triassic boundary. Palaeogeography, Palaeoclimatology, Palaeo-ecology 284, 326–336.

Kürschner, W.M., Herngreen, G.F.W., 2010. Triassic palynology of central and north-western Europe: a review of palynoflora diversity patterns and biostratigraphicsubdivisions. Geological Society London, Special Publications 334, 263–283.

Kustatscher, E., van Konijnenburg-van Cittert, J.H.A., Roghi, G., 2010.Macrofloras and palyno-morphs as possible proxies for palaeoclimatic and palaeoecological studies: a case studyfrom the Pelsonian (Middle Triassic) of Kühwiesenkopf/Monte Prà della Vacca (OlangDolomites, N-Italy). Palaeogeography, Palaeoclimatology, Palaeoecology 290, 71–80.

Kutzbach, J.E., Gallimore, R.G., 1989. Pangaean climates: megamonsoons of the mega-continent. Journal of Geophysical Research 94, 3341–3357.

Kutzbach, J.E., Ziegler, A.M., 1993. Simulation of Late Permian climate and biomes withan atmosphere–oceanmodel: comparisonswith observations. Philosophical Transac-tions of the Royal Society of London. Series B 341, 327–340.

Li, J., 1987. Ordovician acritarchs from the Meitan Formation of Guizhou Province,South-west China. Palaeontology 30 (3), 613–634.

Li, J., Batten, D.J., 2004. Early Cretaceous palynofloras from the Tanggula Mountains of thenorthern Qinghai-Xizang (Tibet) Plateau, China. Cretaceous Research 25, 531–542.

Li, J., Batten, D.J., Yiyong, Z., 2008. Palynological indications of environmental changesduring the Late Cretaceous–Eocene on the southern continental margin of Laurasia,Xizang (Tibet). Palaeogeography, Palaeoclimatology, Palaeoecology 265, 78–86.

Liu, G., Einsele, G., 1994. Sedimentary history of the Tethyan basin in the TibetanHimalayas. Geologische Rundschau 83, 32–61.

Looy, C.V., Brugman, W.A., Dilcher, D.L., Visscher, H., 1999. The delayed resurgence ofequatorial forests after the Permian–Triassic ecologic crisis. Proceedings of the Na-tional Academy of Sciences of the United States of America 96, 13857–13862.

Maheshwari, H.K., 1982. Mesozoic plant fossils from the Himalayas: a critique. ThePalaeobotanist 30 (3), 242–253.

Mundil, R., Metcalfe, I., Ludwig, K.R., Renne, P.R., Oberli, F., Nicoll, R.S., 2001. Timing ofthe Permian–Triassic biotic crisis: implications from new zircon U/Pb age data (andtheir limitations). Earth and Planetary Science Letters 187, 131–145.

Mundil, R., Ludwig, K.R., Metcalfe, I., Renne, P.R., 2004. Age and timing of the Permianmass extinctions: U/Pb dating of closed-system zircons. Science 305, 1760–1763.

Ogg, J.G., von Rad, U., 1994. The Triassic of the Thakkola (Nepal). II: paleolatitudes andcomparison with other Eastern Tethyan Margins of Gondwana. GeologischeRundschau 83, 107–129.

Orchard, M.J., 2007. Conodont diversity and evolution through the latest Permian and EarlyTriassic upheavals. Palaeogeography, Palaeoclimatology, Palaeoecology 252, 93–117.

Orłowska-Zwolińska, T., 1984. Palynostratigraphy of the Buntsandstein in sections ofwestern Poland. Palaeontologia Polonica 29, 161–194.

Ovtcharova, M., Bucher, H., Schaltegger, U., Galfetti, T., Brayard, A., Guex, J., 2006. NewEarly to Middle Triassic U–Pb ages from South China: calibration with ammonoidbiochronozones and implications for the timing of the Triassic biotic recovery.Earth and Planetary Science Letters 243, 463–475.

Page, C.N., 2002. Ecological strategies in fern evolution: a neopteridological overview.Review of Palaeobotany and Palynology 119, 1–33.

Payne, J.L., Kump, L.R., 2007. Evidence for recurrent Early Triassic massive volcanismfrom quantitative interpretation of carbon isotope fluctuations. Earth and Plane-tary Science Letters 256, 264–277.

Payne, J.L., van de Schootbrugge, B., 2007. Life in Triassic oceans: links between planktonicand benthic recovery and radiation. In: Falkowski, P.G., Knoll, A.H. (Eds.), Evolution ofPrimary Producers in the Sea. Elsevier Academic Press, Burlington, pp. 165–189.

Payne, J.L., Lehrmann, D.J., Wei, J., Orchard, M.J., Schrag, D.P., Knoll, A.H., 2004. Largeperturbations of the carbon cycle during recovery from the end-Permian extinc-tion. Science 305, 506–509.

Peng, Y., Yu, J., Gao, Y., Yang, F., 2006. Palynological assemblages of non-marine rocks atthe Permian–Triassic boundary, western Guizhou and eastern Yunnan, SouthChina. Journal of Asian Earth Sciences 28, 291–305.

Price, P.L., 1997. Permian to Jurassic palynostratigraphic nomenclature. In: Green, P.M.(Ed.), The Surat and Bowen Basins. Queensland Department of Mines and Energy,South-east Queensland Brisbane, pp. 137–178.

Rao, R.B., Zhang, Z.G., 1985. A discovery of Permo–Triassic transitional fauna in theQomolangma Feng area: its implications for the Permo–Triassic boundary. XizangGeology 1, 19–31.

Retallack, G.J., 1975. The life and times of a Triassic lycopod. Alcheringa 1, 3–29.Retallack, G.J., 1995. Permian–Triassic life crisis on land. Science 267, 77–80.Riegel, W., 2008. The Late Palaeozoic phytoplankton blackout — artefact or evidence of

global change? Review of Palaeobotany and Palynology 148, 73–90.Saito, R., Kaiho, K., Oba, M., Takahashi, S., Chen, Z.Q., 2011. A terrestrial vegetation turn-

over in the middle of the Early Triassic. In: Håkansson, E., Trotter, J.A. (Eds.), Pro-gramme & Abstracts: The XVII International Congress on the Carboniferous andPermian: Geological Survey of Western Australia Record 2011/20, 108.

Sarjeant, W.A.S., 1973. Acritarchs and Tamanitids from the Mianwali and Tredian For-mations (Triassic) of the Salt and Surghar Ranges, West Pakistan. In: Logan, A.,Hills, L.V. (Eds.), The Permian and Triassic Systems and Their Mutual Boundary: Ca-nadian Society of Petroleum Geology, Memoir, 2, pp. 35–73.

Shen, S.Z., Cao, C.Q., Henderson, C.M., Wang, X.D., Shi, G.R., Wang, Y., Wang, W., 2006.End-Permian mass extinction pattern in the northern peri-Gondwanan region.Palaeoworld 15, 3–30.

Smith, A.G., Smith, D.G., Funnell, B.M., 1994. Atlas of Mesozoic and Cenozoic Coastlines.Cambridge University Press, Cambridge.

Stemmerik, L., Bendix-Almgreen, S.E., Piasecki, S., 2001. The Permian–Triassic bound-ary in central East Greenland: past and present views. Bulletin of the Geological So-ciety of Denmark 48, 159–167.

Strother, P.K., 1996. Acritarchs. In: Jansonius, J., McGregor, D.C. (Eds.), Palynology: Prin-ciples and Applications. American Association of Stratigraphic Palynologists Foun-dation, Norwell, MA, pp. 81–106.

Svensen, H., Planke, S., Polozov, A.G., Schmidbauer, N., Corfu, F., Podladchikov, Y.Y.,Jamtveit, B., 2009. Siberian gas venting and the end-Permian environmental crisis.Earth and Planetary Science Letters 277, 490–500.

Tiwari, R.S., Tripathi, A., 1992.MarkerAssemblage-Zones of spores andpollen species throughGondwana Palaezoic and Mesozoic sequence in India. The Palaeobotanist 40, 194–236.

Tiwari, R.S., Vijaya, Mamgain, V.D., Misra, R.S., 1996. Palynological studies on a latePalaeozoic–Mesozoic Tethyan sequence in the Niti area of the Central Himalaya,Uttar Pradesh, India. Review of Palaeobotany and Palynology 94, 169–196.

Traverse, A., 2007. Paleopalynology. Springer, Dordrecht.Tyson, R.V., 1995. Sedimentary Organic Matter — Organic Facies and Palynofacies.

Chapman & Hall, London.Utting, J., Piasecki, S., 1995. Palynology of the Permian of northern continents: a re-

view. In: Scholle, P.A., Peryt, T.M., Ulmer-Scholle, D.S. (Eds.), The Permian ofNorthern Pangea. : Paleogeography, Paleoclimates, Stratigraphy, 1. Springer,New York, pp. 236–261.

van de Schootbrugge, B., Quan, T.M., Lindström, S., Püttmann, W., Heunisch, C., Pross, J.,Fiebig, J., Petschick, R., Röhling, H.-G., Richoz, S., Rosenthal, Y., Falkowski, P.G.,2009. Floral changes across the Triassic/Jurassic boundary linked to flood basaltvolcanism. Nature Geoscience 2, 589–594.

Van Konijnenburg-Van Cittert, J.H.A., 2002. Ecology of some Late Triassic to Early Cre-taceous ferns in Eurasia. Review of Palaeobotany and Palynology 119, 113–124.

Whiteside, J.H., Ward, P.D., 2011. Ammonoid diversity and disparity track episodes ofchaotic carbon cycling during the early Mesozoic. Geology 39, 99–102.

Yin, L., Di Milia, A., Tongiorgi, M., 1998. New and emended acritarch taxa from thelower Dawan Formation (lower Arenig, Huanghuachang Section, South China). Re-view of Palaeobotany and Palynology 102, 223–248.

Yin, H., Zhang, K., Tong, J., Yang, Z., Wu, S., 2001. The Global Stratotype Section andPoint (GSSP) of the Permian–Triassic Boundary. Episodes 24 (2), 102–114.

24 E. Schneebeli-Hermann et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 339–341 (2012) 12–24