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Fungal abundance spike and the Permian–Triassic boundary in the Karoo Supergroup (South Africa)

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Fungal abundance spike and the Permian–Triassic boundary in the Karoo Supergroup (South Africa)

Abstract and Figures

The most severe mass extinction of marine species and terrestrial vertebrates and plants is associated with the Permian–Triassic boundary (∼251 Ma). The extinction interval is also marked by the disappearance of most Late Permian gymnosperm palynomorphs at a layer containing solely the abundant remains of fungi. This ‘fungal spike’ apparently represents widespread devastation of arboreous vegetation. Stratigraphic and palynological study of the Carlton Heights section in the southern Karoo Basin of South Africa revealed a 1-m-thick fungal spike zone that occurs simultaneously with the last appearance of typically Late Permian gymnosperm pollen. The plant extinction and fungal spike zone are found above the last occurrence of Late Permian mammal-like reptiles of the Dicynodont Zone at other Karoo sections. Using the fungal event as a time line in marine and non-marine sections allows placement of the marine extinctions and the extinction of terrestrial plants and reptiles within a brief crisis interval of less than about 40 000 years at the end of the Permian.
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Fungal abundance spike and the Permian^Triassic boundary
in the Karoo Supergroup (South Africa)
Maureen B. Steiner a, Yoram Eshet b;c, Michael R. Rampino d;e;,
Dylan M. Schwindt d
aDepartment of Geology and Geophysics, University of Wyoming, Laramie, WY 82071, USA
bGeological Survey of Israel, Jerusalem 95501, Israel
cTel Hai Academic College, Tel Hai 12210, Israel
dEarth and Environmental Science Program, New York University, New York, NY 10003, USA
eNASA, Goddard Institute for Space Studies, New York, NY 10025, USA
Received 22 March 2002; accepted 31 December 2002
Abstract
The most severe mass extinction of marine species and terrestrial vertebrates and plants is associated with the
Permian^Triassic boundary (V251 Ma). The extinction interval is also marked by the disappearance of most Late
Permian gymnosperm palynomorphs at a layer containing solely the abundant remains of fungi. This ‘fungal spike’
apparently represents widespread devastation of arboreous vegetation. Stratigraphic and palynological study of the
Carlton Heights section in the southern Karoo Basin of South Africa revealed a 1-m-thick fungal spike zone that
occurs simultaneously with the last appearance of typically Late Permian gymnosperm pollen. The plant extinction
and fungal spike zone are found above the last occurrence of Late Permian mammal-like reptiles of the Dicynodont
Zone at other Karoo sections. Using the fungal event as a time line in marine and non-marine sections allows
placement of the marine extinctions and the extinction of terrestrial plants and reptiles within a brief crisis interval of
less than about 40 000 years at the end of the Permian.
 2003 Elsevier Science B.V. All rights reserved.
Keywords: Permian^Triassic boundary; extinction; fungal spike; vertebrates ; South Africa
1. Introduction
The end-Permian mass extinction eliminated
more than 90% of marine species (Raup, 1979 ;
Jin et al., 2000). Terrestrial biota also su¡ered
dramatically: an estimated 70% of terrestrial ver-
tebrate families were eradicated (Maxwell, 1992),
insects su¡ered a major loss of taxa (Labandiera
and Sepkoski, 1993), and more than 90% of Late
Permian gymnosperm species died out (Retallack,
1995; Visscher et al., 1996; Looy et al., 1999).
The plant extinction is evidenced by the disap-
pearance of almost all Late Permian gymnosperm
pollen at a horizon containing only fungal re-
mains and woody debris (Visscher et al., 1996).
This fungal abundance event was followed by ap-
pearance of an Early Triassic palyno£ora domi-
nated by lycopod spores and bisaccate gymno-
0031-0182 / 03 / $ ^ see front matter 2003 Elsevier Science B.V. All rights reserved.
doi: 10.1016/S0031-0182(03)00230-X
* Corresponding author. Fax: +1-212-995-4015.
E-mail address: mrr1@nyu.edu (M.R. Rampino).
PALAEO 3036 28-4-03
Palaeogeography, Palaeoclimatology, Palaeoecology 194 (2003) 405^414
www.elsevier.com/locate/palaeo
sperm pollen (Eshet et al., 1995; Visscher et al.,
1996). The widespread plant extinction and sub-
sequent £ood of fungal remains has been inter-
preted as indicating destruction of terrestrial veg-
etation and accumulation of decaying organic
debris (Ouyang and Utting, 1990; Eshet et al.,
1995; Visscher et al., 1996; Poort et al., 1997).
This fungal proliferation event has been ob-
served both in terrestrial and shallow marine se-
quences. In marine sections, the brief interval rich
in fungal remains is found close to the level
marked by the mass extinction of marine organ-
isms (Visscher and Brugman, 1986; Visscher et
al., 1996; Twitchett et al., 2001). An abrupt neg-
ative shift in carbon isotopes in the oceans also
occurs close to the time of the reduction in gym-
nosperms (Looy et al., 2000), and the zone
marked exclusively by abundant fungal spores
(Visscher et al., 1996; Wignall et al., 1996). In
some Permian^Triassic sections enrichment in
fungal remains occur at other levels (commonly
the tops of regressive subtidal cycles; Cirilli et
al., 1998), but these are not associated with the
major disappearance of Late Permian pollen, and
the concentration of fungal remains does not
reach the V100% levels seen in the end-Permian
abundance spike.
The widespread end-Permian fungal spike could
provide a timeline for correlating the marine and
non-marine records. A good place to establish this
correlation is the Upper Permian and Lower Tri-
assic Beaufort Group of the Karoo Supergroup of
South Africa, which is well known for its record
of the succession of mammal-like reptiles across
the Permian^Triassic (P^T) boundary (Kitching,
1977; Rubidge, 1995). The demise of the herbiv-
orous dicynodonts of the Dicynodon assemblage
zone, and their replacement by the Lystrosaurus
assemblage fauna has served in the past as the
approximate de¢nition of the P^T boundary in
the Karoo, although the ¢rst occurrence of Ly-
strosaurus is now known to precede the last oc-
currence of Dicynodon (e.g. Smith, 1990, 1995;
Smith and Ward, 2001).
The Beaufort Group consists of an apparently
uninterrupted succession of alluvial sedimentation
(Catuneanu and Elango, 2001). Sediments shed
from the Cape Fold Belt region produced a £uvial
network which prograded across the Karoo Basin
during Late Permian time. Lacustrine mudstones,
£uvial overbank mudstones and channel sand-
stones make up a sedimentary sequence up to
6 km thick in the Karoo Basin in South Africa.
A change from predominantly green mudstone
and sandstone deposited by high sinuosity river
systems to multistoried channel and sheet sand-
stones intercalated with maroon mudstones, typi-
cal of deposition by braided streams, occurs close
to the P^T boundary (as de¢ned by the vertebrate
assemblages) (Smith, 1990, 1995; Ward et al.,
2000; Smith and Ward, 2001).
We studied the stratigraphy and palynology of
the well-exposed Carlton Heights section, located
along the Graa¡-Reinet^Colesburg highway be-
tween Middleburg and Neupoort, South Africa
(Fig. 1). Samples were collected in gullies to the
southeast and below the main highway (on the
B.P. Erasmus farm, ‘Beskuitfontein’), and along
the main highway itself (the road is at the 57 m
level in our section) about 500 m north of the
Carlton Heights railway stop (GPS : 31‡13.03PS,
24‡56.96PE).
2. Stratigraphy of the Carlton Heights
section
At the Carlton Heights locality (Fig. 2), £at
lying, predominantly greenish mudstone, siltstone
and thin tabular sandstones dominate the lower
part of the section. These were previously mapped
as Upper Permian (Balfour Formation) (Keyser,
1977) based on lithology and stratigraphic posi-
tion relative to the subsequent widespread change
from mudstone to dominantly sandstone facies. A
Late Permian age for these deposits is also sug-
gested by our discovery of a large hip bone and
other skeletal elements possibly belonging to Di-
cynodon sp. in the lower part of the section (be-
tween 2.8 and 10.5 m above the base of the sec-
tion) (Fig. 2).
At about 33.5 m above the base of the Carlton
Heights section, the green mudstone/sandstone se-
quence is overlain by V15 m of laminated to
massive maroon mudstone with occasional thin
sands (Fig. 3; well-exposed in the railroad cut
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M.B. Steiner et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 194 (2003) 405^414406
just to the south of our section), capped by a 4^
5 m-thick grayish^green sand unit. Lystrosaurus
¢rst occurs in our section at 38 m above the
base. Based on lithology and stratigraphic posi-
tion, we correlate this laminated maroon mud-
stone with a similar unit recently identi¢ed by
Smith and Ward (2001) at the Bethulie and Loots-
berg Pass sections in the Karoo. An increased
number of Lystrosaurus fossils were noted near
the top of this unit at Carlton Heights (V51 m
above the base of the section).
At V56 m above the base of the Carlton
Heights section, the maroon mudstone and sand-
stone unit grades upward into thin-bedded alter-
nating green and red siltstones and ¢ne sand-
stones showing abundant sub-horizontal cylindri-
cal burrows (Fig. 4). The thin-bedded burrowed
unit is overlain (at 58.5 m above the base of the
section) by a thin (V5-cm-thick), very ¢ne-
grained clay-rich layer. This laterally continuous
(on outcrop scale) layer is heavily burrowed, and
is marked by red and yellow^brown alteration
products (Fig. 4). Clay-mineral analysis by stan-
dard semi-quantitative X-ray di¡raction methods
(Brindley and Brown, 1980) shows that the layer
is composed predominantly of illite and illite^
smectite. The layer also contains quartz, low al-
bite, gypsum, chlorite, mica, and jarosite, and
thus has a heavily weathered detrital signature.
About 0.5 m above this marker layer (at 59 m
above the base of the section), the ¢rst laterally
widespread multistoried sandstone with an ero-
sional base containing lenses of mud-pebble and
carbonate-nodule conglomerates (identi¢ed with
the base of the Katberg Formation) is encoun-
tered (Figs. 2 and 4).
The Katberg Formation at Carlton Heights
(s270 m in total thickness) is represented by a
facies dominated by gray and white ¢ne- to
coarse-grained sandstone that is typically multi-
storied and laterally extensive (Fig. 4). The sands
commonly show scoured bases with lenses of in-
tra-formational mud-pebble and pedogenic car-
bonate-nodule conglomerates, horizontal strati¢-
cation, and large-scale trough cross strati¢cation
(Smith, 1995). The thick multistoried sands are
interbedded with thin red mudstone units showing
desiccation features, such as sand-¢lled mud-
cracks.
3. Palynology
We sampled a total of 73 m at 0.5^3-m intervals
Fig. 1. Location map showing the Carlton Heights locality, Karoo Basin, South Africa.
PALAEO 3036 28-4-03
M.B. Steiner et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 194 (2003) 405^414 407
(Fig. 2). Palynological slides were prepared for
microscopic study using standard procedures
(Doher, 1980). Out of the 29 samples that were
analyzed for palynomorphs, only seven were bar-
ren. The palynomorph species distribution within
the sampled section is shown in Fig. 5. Three
palynological assemblage zones were identi¢ed in
the Carlton Heights section:
Fig. 2. Stratigraphic section across the P^T boundary in Karoo Supergroup strata at Carlton Heights, South Africa. The upper-
most 11 m in the Katberg Formation sandstones studied are not shown, as they were barren of palynofossils. Asterisks indicate
samples analyzed for pollen and spores. Dicynodon sp.? indicates skeletal material possibly belong to Dicynodon sp.
PALAEO 3036 28-4-03
M.B. Steiner et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 194 (2003) 405^414408
(1) The Late Permian Klausipollenites schauber-
geri Zone, dominated by taxa of the form genera
Protohaploxypinus and Falcisporites.
(2) An interval composed almost entirely of
fungal cell remains (Reduviasporonites or its junior
synonyms Chordecystia or Tympanicysta)(Vis-
scher et al., 1996) and abundant recycled woody
material ^ the fungal spike zone (Fig. 5). The fungal
spike interval is only V1 m thick (57.6^58.6 m
above the base of the section) (Fig. 2). (We note
that some researchers have interpreted Tympani-
cysta as a green alga (Afronin et al., 2001), but
most workers agree on the fungal interpretation
(Visscher et al., 1996.)
(3) The fungal spike is followed by the Early
Triassic Kraeuselisporites^Lunatisporites Zone,
dominated by species of the lycopod Kraeuseli-
sporites and the bisaccate pollen Lunatisporites
and Platysaccus.
The interval from V49 m to 51.2 m in the
section was found to be barren of palynomorphs,
and eight of the 17 Late Permian palynomorph
taxa that we identi¢ed last occur at or below
this barren zone. The other nine Late Permian
taxa have last occurrences at or just below the
base of the fungal spike zone (Fig. 5). The last
occurrences just prior to the lower barren zone
could represent an initial decrease in plant diver-
sity as part of a crisis period extending over some
tens of thousands of years. On the other hand, the
Fig. 3. Laminated to massive maroon mudstone with thin siltstone interbeds along the railway cut northeast of the Carlton
Heights railway stop (person for scale) (see Fig. 2). This lithologic unit is believed to be correlative with the P^T event beds of
Smith and Ward (2001) described from the Bethulie and Lootsberg Pass sections in the Karoo.
PALAEO 3036 28-4-03
M.B. Steiner et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 194 (2003) 405^414 409
reduction in palynomorphs could be the result of
poor preservation of pollen and spores in sandy
deposits.
4. The fungal spike and the end-Permian mass
extinction
The characterization of the P^T boundary in-
terval by a severe land-plant extinction and an
abrupt, short-lived £ood of fungal remains is
now apparent from numerous studies around
the world (Visscher and Brugman, 1986; Eshet
et al., 1995; Visscher et al., 1996). Previous stud-
ies of Karoo Supergroup rocks produced a paly-
nozonation scheme for this time span that showed
evidence of a major turnover or extinction of
palynomorphs at or near the P^T boundary (as
de¢ned by the vertebrate assemblages) (Anderson,
1977; Stapleton, 1978; Utting, 1979; Nyambe and
Utting, 1997). In sub-Equatorial Africa, a fungal
abundance spike has been reported in sections
spanning the P^T boundary from Kenya (Hankel,
1992) and Madagascar (Wright and Askin, 1987).
The widespread fungal proliferation near the
P^T boundary has been interpreted by a number
of workers as re£ecting loss of arboreous vegeta-
tion on a large scale, a major decrease in standing
biomass, and the build-up of decaying vegetation
on land (Visscher and Brugman, 1986; Visscher et
al., 1996). In the same interval, the plant macro-
fossil record shows the extinction of the Glosso-
pteris £ora across Gondwana, and the disappear-
ance of related Vertebraria root traces (Retallack,
1995). Recovery from the extinction and renewed
diversi¢cation in land-plants were relatively slow,
taking about 4 Myr (Eshet et al., 1995 ; Looy et
al., 1999).
The £ood of fungal remains was apparently a
short-lived event. In the Carlton Heights se-
quence, the zone marked exclusively by fungal
remains spans only V1 m of the sedimentary rec-
KATBERG
SANDSTONE
clay-rich layer
Fungal Spike
BALFOUR
FORMATION
Fig. 4. The fungal spike zone just below the base of the Katberg Formation on the Graa¡-Reinet^Colesburg highway at Carlton
Heights. The fungal spike zone, showing thin-bedded strati¢cation and sub-horizontal burrowing, is V1 m thick (from 57.5 to
58.5 m in the section). The fungal spike zone is capped by a clay-rich layer with red to yellow^brown alteration. The one meter
white bar is for scale.
PALAEO 3036 28-4-03
M.B. Steiner et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 194 (2003) 405^414410
ord (Figs. 2 and 5). At minimum estimated accu-
mulation rates for the sediments of the Balfour
Formation, this would mean 92000 years dura-
tion for the episode, with burrowing and the
mixed depositional regimes probably making this
an upper limit. Sedimentologic evidence of the
dramatic loss of terrestrial vegetation ^ the
marked lithologic change to the ¢rst thick, multi-
storied channel and sheet sandstones typical of
braided streams (Katberg Formation) (Ward et
al., 2000) ^ occurs about 50 cm (estimated as
91000 years) above the fungal spike zone at
Carlton Heights (Fig. 4).
The results of several recent studies allow us to
compare the timing of the extinction of terrestrial
plants and reptiles with the marine extinctions.
Twitchett et al. (2001) studied a marine section
in Greenland that contained abundant and well-
preserved marine fauna as well as terrestrial paly-
nomorphs. The sediments also recorded the neg-
ative excursion in N13C in marine carbonate and
organic carbon. Based on estimated sedimentation
rates, Twitchett et al. (2001) concluded that the
marine and terrestrial ecosystem collapse occurred
over the same stratigraphic interval and took just
a few tens of thousands of years. The faunal and
£oral extinctions were apparently coeval with the
initial negative shift in N13C. The rapid N13C shift
could be a result of the rapid loss of primary
productivity in the oceans and on land (Caldeira
and Rampino, 1993), and the enhanced delivery
of light carbon (including terrestrial plant debris)
to the ocean £oor (Broecker and Peacock, 1999 ;
Sephton et al., 2002).
Woody debris
Densoisporites complicatus
Densoisporites playfordii
Falcisporites stabilis
Falcisporites zapfei
Klausipollenites schaubergeri
Protohaploxypinus limpidus
Protohaploxypinus microcorpus
Protohaploxypinus richteri
Protohaploxypinus samoilovichii
Punctatosporites sp.
Reticuloidosporites warchianus
Triplexisporites playfordii
Guthoerlisporites cancellosus
Protohaploxypinus varius
Vittatina ovalis
Laevigatosporites callosus
Protohaploxypinus jacobii
Lueckisporites singhii
Limitisporites sp.
Fungal cells
Lunatisporites noviaulensis
Kraeuselisporites cuspidus
Kraeuselisporites sp.
Lunatisporites pellucidus
Lunatisporites transversundatus
Platysaccus leschickii
Platysaccus quenslandi
Platysaccus papilionis
Lundbladispora brevicula
Lunatisporites sp.
72.3
71.9
59.5
59.04
59 ||
58.95 || | |
58.8 ||||
58.75 |||
58.7 |
58.64
58.59
58.3
58.2
58.1
57.6
55.5
54.34 | |
52.64 | | | |
51.2 | | | | | | | | |
50.7 | | | | | | | | |
50.3 | | | | | | | | |
49 | | | | | | | | |
48.5 | | | | | | | |
38.3 | | | | | |
33.35 | |||| | | | |
26.6 | | | |||| | ||
23.6 | || | | ||||||
10.6 | | | | | | | |
0.35
0 || |||||
Sample Depth (m)
Zone
Age
Kraeuselisporites-
Lunatisporites spp.
Fungal
Spike
Klausipollenites
schaubergeri
Early Triassic
P-T
Boundary
Z
one
Late Permian
BARREN (sandstone)
BARREN
1.0
Fungal Spike Zone
Thickness (m)
72.3
Fig. 5. Distribution chart (not to scale) of palynomorphs identi¢ed in the Carlton Heights stratigraphic section. The fungal spike
interval, marked exclusively by fungal remains and woody debris, is V1 m in thickness.
PALAEO 3036 28-4-03
M.B. Steiner et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 194 (2003) 405^414 411
A similarly negative N13C isotope shift has been
reported from some terrestrial sections (Morante,
1996; Krull and Retallack, 2000), and from mo-
lecular fossils in land-plant leaf cuticles deposited
in marine sediments (Sephton et al., 2002), most
likely re£ecting a synchronous atmospheric car-
bon isotope shift. Recently, a negative excursion
in carbon isotope ratios has been reported from
carbonate soil nodules and bone material from
the Bethulie section in the Karoo Basin (MacLeod
et al., 2000). Thus, based on the results of Twitch-
ett et al. (2001), the negative excursion in N13Cin
the Karoo section should be very close to the time
of the marine extinction and the devastation of
terrestrial ecosystems.
At Bethulie, the initiation of the N13C excursion
at about 45 m in the section coincides with the
local ¢rst appearance of Lystrosaurus; the N13 C
values begin to return to their former levels after
the last appearance of Dicynodon at 57 m (Mac-
Leod et al., 2000). The carbon isotope anomaly
corresponds to the base of the laminated maroon
mudstone event beds in which Smith and Ward
(2001) place the P^T boundary. At average sedi-
mentation rates for Karoo deposits (50 cm/1000
years) the interval of the laminated event beds
and the overlap of Dicynodont sp. and Lystrosau-
rus would be about 25 000 years.
At the Carlton Heights locality, the base of the
fungal spike zone is about 20 m above the base of
the maroon mudstone event beds (Fig. 2). At
average sedimentation rates for Karoo deposits,
the base of the P^T event beds could be about
40 000 years prior to the fungal spike but these
calculations are somewhat uncertain.
5. Conclusions
Palynological study at Carlton Heights identi-
¢ed a 1-m-thick zone containing only abundant
fungal remains and woody debris coincident
with the last appearance of typically Late Permian
gymnosperm palynomorphs. The zone apparently
represents proliferation of fungi upon large vol-
umes of decaying plant matter. This fungal spike
occurs just below the ¢rst Katberg Sandstone,
which signi¢es a basin-wide change to braided
stream patterns, probably related to the wide-
spread loss of vegetation (Ward et al., 2000).
The latest Permian £ood of fungal remains
might serve as a widespread marker bed of brief
duration in marine and non-marine deposits. In
marine sections, the fungal spike has been esti-
mated to be coeval with the marine extinction
and the negative shift in carbon isotopes that oc-
curred at the end of the Permian (Twitchett et al.,
2001). The discovery of the fungal spike in the
classic fossiliferous Karoo sequence, within the
interval of dramatic faunal turnover in terrestrial
vertebrates and land-plants, allows correlation of
the terrestrial and marine mass extinctions at the
P^T boundary.
The stratigraphy at Carlton Heights, when
combined with the recent work of Smith and
Ward (2001) on other Karoo sections, suggests
that the disappearance of typically Late Permian
vertebrates in the Karoo Basin and the ¢nal gym-
nosperm plant extinction and fungal spike zone
took place over an interval of less than 40 000
years.
Acknowledgements
We thank John Hancox, Isabel Montanez, and
Neil Tabor for help in the ¢eld, Robert C. Rey-
nolds at Dartmouth College for X-ray di¡raction
mineral analyses, Henk Brinkhuis, Roger M.H.
Smith and Peter D. Ward for helpful discussions
and information, and Simonetta Cirilli and Eve-
lyn Krull for critical reviews. M.R.R. was sup-
ported in part by a New York University Re-
search Challenge Grant. We are grateful to the
B.P. Erasmus and G. Van Zyl families for permis-
sions and assistance in the Karoo.
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... An abundance of Reduviasporonites (¼Tympanicystia ¼ Chordecystia), an environment-dependent taxon, cannot be used as a chronostratigraphic marker because it can be recognized outside the P-T boundary according to Foster et al. (2002) and Spina et al. (2015). Reduviasporonites has been reported from latest Permian successions such as in Israel, the Southern Alps, South Africa, and South China (Ouyang and Utting 1990;Eshet et al. 1995;Steiner et al. 2003;Bercovici et al. 2015;Bercovici and Vajda 2016). However, the species is also recorded in Early Triassic deposits by Schneebeli- Hermann and Bucher (2015) throughout the P-T Amb succession in Salt Range, Pakistan and Mays et al. (2021) in the uppermost Lopingian to Lower Triassic of the Sydney Basin (Australia). ...
... In South Africa, the Early Triassic Kraeuselisporites-Lunatisporites Biozone (Steiner et al. 2003) is similar to the floras described here by the presence of cavate spores (Kraeuselisporites spp., and Lundbladispora brevicula) and Lunatisporites noviaulensis, L. transversundatus, and Platysaccus spp. pollen. ...
... Late Permian assemblages similar to the oldest APP6 assemblages are those from the McKinnon Member of the Prince Charles Mountains, Antarctica (Lindström and McLoughlin, 2007), and at the base of the Buckley Formation, Graphite Peak, Antarctica (Collinson et al., 2006). The Klausipollenites schaubergeri Zone recognised by Steiner et al. (2003) at the Carleton Heights section, southern Karoo Basin, is correlative with younger assemblages in the P. microcorpus and the APP6 zones. The base of the APP6 zone has been correlated to the upper Chhidru Formation in the Salt Range, Pakistan, which has independently been dated as early Changhsingian (Foster et al., 1997). ...
... Anderson and Anderson (1985) described Pleuromeia-like stems (Gregicaulis dubius (Seward) Anderson and Anderson) from the Burgersdorp Formation. Steiner et al. (2003) recorded a dominance of lycopsid spores in their Early Triassic Kraeuselisporites-Lunatisporites spp. assemblage from the Carleton Heights section, southern Karoo Basin. ...
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... There are additional evidence for microbial proliferation following the EPE and this comes in several forms: (1) Proliferation of algal cysts in both marine [60] and freshwaters [61]. (2) Proliferation of fungi in both marine and freshwaters [62][63][64][65]. (3) Spikes in microbially generated amorphous organic matter (AOM) in palynological residues [66,67]. ...
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... The stratigraphic record of the Karoo Basin provides highresolution data on the terrestrial end-Permian mass extinction among land vertebrates and potentially reflects the nature of the terrestrial extinction event on wider geographic scales or globally. Studies of the marine fossil record in South China (Meishan) identify a rapid extinction and fluctuating negative δ 13 C excursions (31,32,35,42,43,60,61) occurring prior to and coincident with the Permo-Triassic Boundary (PTB) at 251.902 ± 0.024 Ma. The Karoo fossil record has been used as a benchmark for the continental extinction (e.g., 38-40, 51, 56). ...
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Earth’s largest biotic crisis occurred during the Permo–Triassic Transition (PTT). On land, this event witnessed a turnover from synapsid- to archosauromorph-dominated assemblages and a restructuring of terrestrial ecosystems. However, understanding extinction patterns has been limited by a lack of high-precision fossil occurrence data to resolve events on submillion-year timescales. We analyzed a unique database of 588 fossil tetrapod specimens from South Africa’s Karoo Basin, spanning ∼4 My, and 13 stratigraphic bin intervals averaging 300,000 y each. Using samplestandardized methods, we characterized faunal assemblage dynamics during the PTT. High regional extinction rates occurred through a protracted interval of ∼1 Ma, initially co-occurring with low origination rates. This resulted in declining diversity up to the acme of extinction near the Daptocephalus–Lystrosaurus declivis Assemblage Zone boundary. Regional origination rates increased abruptly above this boundary, co-occurring with high extinction rates to drive rapid turnover and an assemblage of short-lived species symptomatic of ecosystem instability. The “disaster taxon” Lystrosaurus shows a long-term trend of increasing abundance initiated in the latest Permian. Lystrosaurus comprised 54% of all specimens by the onset of mass extinction and 70% in the extinction aftermath. This early Lystrosaurus abundance suggests its expansion was facilitated by environmental changes rather than by ecological opportunity following the extinctions of other species as commonly assumed for disaster taxa. Our findings conservatively place the Karoo extinction interval closer in time, but not coeval with, the more rapid marine event and reveal key differences between the PTT extinctions on land and in the oceans.
... The stratigraphic record of the Karoo Basin provides highresolution data on the terrestrial end-Permian mass extinction among land vertebrates and potentially reflects the nature of the terrestrial extinction event on wider geographic scales or globally. Studies of the marine fossil record in South China (Meishan) identify a rapid extinction and fluctuating negative δ 13 C excursions (31,32,35,42,43,60,61) occurring prior to and coincident with the Permo-Triassic Boundary (PTB) at 251.902 ± 0.024 Ma. The Karoo fossil record has been used as a benchmark for the continental extinction (e.g., 38-40, 51, 56). ...
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Significance Mass extinctions permanently altered life’s evolutionary trajectory five times in Earth’s history, and the end-Permian extinction was the greatest of these biotic crises. South Africa’s unparalleled fossil record provides a window into mass extinction dynamics on land. We analyze a unique dataset comprising hundreds of precisely positioned tetrapod fossils, identifying a protracted (∼1 Ma) extinction. This contrasts with the rapid marine extinction, demonstrating that the effects of biotic crises vary prominently among Earth’s surface environments. We also identify the blooming of “disaster taxa” before the main extinction rather than in its aftermath as assumed previously. These changes contributed to breaking the incumbency of previously dominant mammal relatives (synapsids) after the extinction and to the Triassic rise of crocodile- and dinosaur-line archosaurs.
... splendens, Densoisporites sp., Kraeuselisporites sp. and Reduviasporonites chalastus. This incertae sedis organic microfossil relatively long range from Capitanian (late Guadalupian) to early Triassic and widespread occur in different countries as well as Australia, Greenland, South China (Meishan, GSSP of Permian-Triassic boundary), Russian Platform, UK, Austria, USA, South Africa and other (e.g., [91][92][93][94][95]). In the Guadalupian of Northern Gondwana regions (e.g., Turkey; Oman, Saudi Arabia, Iran, Pakistan) R. chalastus was documented in assemblage with Thymospora opaqua, Distriatites insolitus, Hamiapollenites spp., Kraeuselisporites sp. ...
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... The drop in diversity and abundance of pollen grains is mainly observed for the peat-forming glossopterids, peltasperms and Cordaites plants (Mishra et al., 2017). The decline of peatforming vegetation, presence of abnormal pollen grains, spore clusters and acritarch spike accompanied with the dominance of lycopsid spores Balme, 1970;Utting, 1978;Nyambe and Utting, 1997;Aitken, 1998;Steiner et al., 2003;Lindström and McLoughlin, 2007;Prevec et al., 2010;Dawit, 2014;Pereira et al., 2016 Striatopodocarpites -Crescentipollenites MCP-7 Lopingian Balme, 1970;Kyle, 1977;Foster, 1982;Farabee et al., 1991;Hankel, 1992;Backhouse, 1993;Playford and Dino, 2005;Souza and Marques-Toigo, 2005;Lindström and McLoughlin, 2007;Jan et al., 2009;Gutiérrez et al., 2011;Awatar et al., 2014;Schneebeli-Hermann et al., 2011a -Densipollenites MCP-7, MCP-8 Falcon, 1975;Goubin, 1985;Backhouse, 1991;Mory and Backhouse, 1997;Nyambe and Utting, 1997;Souza, 2006;Lindström and McLoughlin, 2007;Prevec et al., 2009;Barbolini et al., 2016Faunipollenites -Striasulcites MCP-8 Guadalupian Falcon, 1975Utting, 1976;Falcon et al., 1984;Backhouse, 1991;Mory and Backhouse, 1997;Nyambe and Utting, 1997;Aitken, 1998;Modie and Le Hérissé, 2009;Gutiérrez et al., 2010;Götz and Ruckweid, 2014;Barbolini et al., 2016 points to deteriorating climatic conditions (increased aridity) from the late Permian to Early Triassic. ...
Article
The Permian–Triassic Mass Extinction (PTME) event was the largest bio crisis to date, adversely affecting life on land and sea. The PTME event is evidenced in India by the destruction of glossopterids with immense loss of peat-forming vegetation, its replacement by stress-tolerant lycopsids, Lilliput Effect and the presence of numerous acritarchs and abnormal pollen grains. However, there are no reports for algal or acritarch spikes. We document, for the first time, an acritarch spike in the Indian subcontinent from the uppermost Permian to Lower Triassic sequence from the Pranhita–Godavari (P-G) Basin. Lithostratigraphically, the late Permian and Early Triassic aged deposits in the P-G basin are designated as the Kamthi Formation. The formation has a very rich and diverse assemblage of pollen grains, spores and acritarchs. Based on a palynological study, an abundance of Leiosphaeridia dessicata comb. nov. emend. has been identified from sediment samples from the two bore cores (MCP-7 and MCP-8) of the Chintalapudi sub-basin, P-G basin. The acritarch appearance and abundance occurred in synchronization with the floral shift. The acritarch appears along with the stress-tolerant lycopsid spores in the uppermost Permian assemblage and increases in accordance with lycopsid spores in the Lower Triassic assemblages. The morphology of Leiosphaeridia dessicata comb. nov. emend. relates its close affinity with an extant marine algal cyst of Acetabularia acetabulum. Moreover, the presence of gammacerane and methylate chromans in the host sediment indicates the hypersaline water column during the deposition. Thus, based on the presence of marine and hypersaline biomarkers and affinity of L. dessicata comb. nov. emend. with marine alga (probably Prasinophyceae or Chlorophyceae) infer that the deposition during the uppermost Permian and Lower Triassic occurred under shallow marine conditions, contradictory to the earlier belief that Indian Upper Permian and Triassic deposits are entirely terrestrial. The possible marine incursion in the P-G basin may have occurred from the eastern continental margin along western Australia or through a passage between the Indian southern margin and the west margin of Antarctica.
... Correlations with the well-studied Karoo Basin succession, South Africa, are hampered by scarce radiogenic-isotope ages and conflicting interpretations concerning the placements of the EPE and PTB (Smith and Ward, 2001;Gastaldo et al., 2005;Ward et al., 2005;Gastaldo et al., 2015;Neveling et al., 2016;Gastaldo et al., 2018;Gastaldo et al., 2020). Although mudrockdominated intervals rich in fungal/algal fossils and vertebrate burrows are known from close to the EPE in the Karoo Basin (Retallack et al., 2003;Steiner et al., 2003;Gastaldo and Rolerson, 2008), precise correlation with the FBM is confounded by repetition of these mudrock facies through the Karoo Basin Permian-Triassic transition. Further north, laminated lacustrine fish beds (c. ...
Article
Full-text available
The newly defined Frazer Beach Member of the Moon Island Beach Formation is identified widely across the Sydney Basin in both outcrop and exploration wells. This thin unit was deposited immediately after extinction of the Glossopteris flora (defining the terrestrial end-Permian extinction event). The unit rests conformably on the uppermost Permian coal seam in most places. A distinctive granule-microbreccia bed is locally represented at the base of the member. The unit otherwise consists of dark gray to black siltstone, shale, mudstone and, locally, thin lenses of fine-grained sandstone and tuff. The member represents the topmost unit of the Newcastle Coal Measures and is overlain gradationally by the Dooralong Shale or with a scoured (disconformable) contact by coarse-grained sandstones to conglomerates of the Coal Cliff Sandstone, Munmorah Conglomerate and laterally equivalent units. The member is characterized by a palynological “dead zone” represented by a high proportion of degraded wood fragments, charcoal, amorphous organic matter and fungal spores. Abundant freshwater algal remains and the initial stages of a terrestrial vascular plant recovery flora are represented by low-diversity spore-pollen suites in the upper part of the unit in some areas. These assemblages are referable to the Playfordiaspora crenulata Palynozone interpreted as latest Permian in age on the basis of high precision Chemical Abrasion Isotope Dilution Thermal Ionization Mass Spectrometry (CA-IDTIMS) dating of thin volcanic ash beds within and stratigraphically bracketing the unit. Plant macrofossils recovered from the upper Frazer Beach Member and immediately succeeding strata are dominated by Lepidopteris (Peltaspermaceae) and Voltziopsis (Voltziales) with subsidiary pleuromeian lycopsids, sphenophytes, and ferns. Sparse vertebrate and invertebrate ichnofossils are also represented in the Frazer Beach Member or in beds immediately overlying this unit. The Frazer Beach Member is correlative, in part, with a thin interval of organic-rich mudrocks, commonly known as the “marker mudstone” capping the Permian succession further to the north in the Bowen, Galilee and Cooper basins. The broad geographic distribution of this generally <5-m-thick mudrock unit highlights the development in eastern Gondwana of extensive, short-lived, shallow lacustrine systems with impoverished biotas in alluvial plain settings in the immediate aftermath of the end-Permian biotic crisis.
... splendens, Densoisporites sp., Kraeuselisporites sp. and Reduviasporonites chalastus. This incertae sedis organic microfossil relatively long range from Capitanian (late Guadalupian) to early Triassic and widespread occur in different countries as well as Australia, Greenland, South China (Meishan, GSSP of Permian-Triassic boundary), Russian Platform, UK, Austria, USA, South Africa and other (e.g., [91][92][93][94][95]). In the Guadalupian of Northern Gondwana regions (e.g., Turkey; Oman, Saudi Arabia, Iran, Pakistan) R. chalastus was documented in assemblage with Thymospora opaqua, Distriatites insolitus, Hamiapollenites spp., Kraeuselisporites sp. ...
Preprint
We review and refine the geological setting of an area located nearby the Tyrrhenian seacoast, in the inner zone of the Northern Apennines (southern Tuscany), where a Neogene monzogranite body (estimated in about 3 km long, 1.5 km wide, and 0.7 km thick) emplaced during early Pliocene. This magmatic intrusion, known as the Gavorrano pluton, is partially exposed in a ridge bounded by regional faults delimiting broad structural depressions. A widespread circulation of geothermal fluids accompanied the cooling of the magmatic body and gave rise to an extensive Fe-ore deposit (mainly pyrite) exploited during the past century. The tectonic setting which favoured the emplacement and exhumation of the Gavorrano pluton is strongly debated with fallouts on the comprehension of the Neogene evolution of this sector of the inner Northern Apennines. Data from a new fieldwork dataset, integrated with information from the mining activity, have been integrated to refine the geological setting of the whole crustal sector where the Gavorrano monzogranite was emplaced and exhumed. Our review, implemented by new palynological, petrological and structural data pointed out that: i) the age of the Palaeozoic phyllite (hosting rocks) is middle-late Permian, thus resulting younger than previously described (i.e. pre-Carboniferous); ii) the P-T conditions at which the metamorphic aureole developed are estimated at about 660 °C and at a maximum depth of c. 5 km; iii) the tectonic evolution which determined the emplacement and exhumation of the monzogranite is constrained in a transfer zone, in the frame of the extensional tectonics affecting the area continuously since Miocene.
Article
Full-text available
This study reviews plant species richness and abundance change from the End Permian to Middle Triassic in South China and examines the co-evolutionary relationship between the flora and the environment through this critical interval in the history of terrestrial biotas. A normalized macro-fossil plant record, that considers only one taxon per whole plant, is produced. This identifies four broad phases of plant evolution. Phase 1 is marked by pre-extinction floras that demonstrate a long-term decline of species richness beginning in the Late Permian (lower Changhsingian) that culminates in the distinct End Permian Plant Crisis (EPPC) at the end of the Changhsingian. Other evidence for the health of the flora, including palynology, biomarkers, wildfire proxies, soil erosion and weathering proxies show a drastic loss of plant abundance (biomass) and increase of wildfire frequency (suggestive of increasing seasonal aridity) during the EPPC. A Phase 2 survival interval, during the Changhsingian–Griesbachian transition, has a severely impoverished plant assemblage consisting of opportunistic lycopods and a short-lived holdover flora. Phase 3 (Late Griesbachian–Smithian) saw the modest recovery of species richness as several groups began to radiate, notably conifers and ferns. Diversity increases substantially and persistently during the succeeding Phase 4 and sees the dominant lycopods/herbaceous bryophytes of Phase 3 replaced by conifer-dominated floras. Plant abundance recovery began earlier than the resumption of coal formation which only initiated in the Anisian following its disappearance during the EPPC. Only in the Late Triassic did the flora recover to a level comparable to that seen in the Permian. The flora of South China thus took ~15 million years to completely recover from the profound environmental and climatic effects of the Permo-Triassic mass extinction.
Article
Full-text available
Filamentous microfossils Tympanicysta Balme, formerly interpreted as conidia of ascomycetes, are similar to zygnemataceous algae Spirogyra Link in the gen-eral morphology, folding of transverse septa, chloroplasts and akinetes. Their rise at about the Permian-Triassic boundary is, therefore, unrelated to the boundary "fungal event", but is rather a consequence of a Permian-Triassic widespread ponding and swamping of river systems at the initial stage of the end Permian transgression. RÉSUMÉ Épanouissement des algues vertes Tympanicysta Balme à la limite du Permien et du Trias. Le microfossile filamenteux Tympanicysta Balme, jadis interprété comme un champignon ascomycète, est plutôt à rapprocher de Spirogyra Link (algues vertes Zygnemataceae), dont il possède la morphologie, le plissement des septa transversaux, les chloroplastes et les akinètes. Son épanouissement à la limite du Permien et du Trias n'est donc pas lié à un « événement fungique » mais à une grande transgression marine.
Article
The non-marine tetrapods of the Permian and Early Triassic experienced four significant episodes of extinction during a time of relatively high turnover at the family level. The Artinskian, Ufimian, and Scythian extinctions appear genuine, but the Tatarian extinction is compromised by spurious data. The quality of the Tatarian data is considered in the light of the poor stratigraphical record for the Late Permian and Permian-Triassic boundary. Various extinction mechanisms are considered, bearing in mind that the radiation of the mammal-like reptiles forms a large portion of the diversity data. The most likely hypothesis is that non-marine tetrapods were subjected to environmental stress as climates fluctuated, at first in association with glaciation, and then with continental warming. -Author
Article
Surface and subsurface rock samples contain plant microfossils which locate the Permian-Triassic boundary within the Sakamena Group of southern Madagascar. Upper Permian rocks in Madagascar are unique because unusually high proportions of Guttulapollenites and Weylandites pollen are found together with occasional specimens of Lunatisporites pellucidus, a species elsewhere considered diagnostic of the Triassic. The lower most Triassic strata in Madagascar, however, contain a more characteristic Gondwana assemblage including trilete cavate spores (Densoisporites, Lundbladispora and Kraeuselisporites spp.), other diagnostic spores, and taeniate bisaccate pollen (Lunatisporites spp.). Organic-walled microphytoplankton from some horizons in the lower half of the Middle Sakamena Group record the extensive marine transgression recognized worldwide for the earliest Triassic. We believe that the Lower Middle Sakamena succession corresponds to that of the upper Chhidru to Kathwai-Mittiwali sequence of the Salt Range, Pakistan, with the Permian-Triassic boundary approximating the Lower-Middle Sakamena transition.