Tanner, L.H., Spielmann, J.A. and Lucas, S.G., eds., 2013, The Triassic System. New Mexico Museum of Natural History and Science, Bulletin 61.
296
A SYNTHESIS OF THE RICH GONDWANA TRIASSIC
MEGAFOSSIL FLORA FROM NYMBOIDA, AUSTRALIA
W.B. KEITH HOLMES1 AND H.M. ANDERSON2
1
Hon. Research Fellow, University of New England, Armidale, 46 Kurrajong Street, Dorrigo, NSW, Australia 2453, email: [email protected];
2
Hon. Palaeobotanist, BPI Palaeontology, University of Witwatersrand, Johannesburg, South Africa, email: [email protected]
Abstract—This synthesis of the Nymboida megafossil flora, based on a series of nine descriptive taxonomic
papers, provides the first comprehensive account of a Triassic fossil flora in Australia in the twenty-first century.
From a fossil flora perspective the Nymboida Coal Measures, located southwest of the city of Grafton in northern
New South Wales, are highly significant as they are the source of the oldest commercial coal seams in the world
following the "coal gap" after the disastrous Permian-Triassic extinction events. Similarity of the Nymboida flora
to the Kaihikuan floras of New Zealand suggests a Ladinian age. The previously active Coal Mine and Reserve
Quarries, which lie in the Basin Creek Formation, have yielded over many years a very rich and diverse Triassic
flora. To date a total of 58 genera, 105 species and another 28 forms that have insufficient detail preserved for
specific identification have been described. Due to a tectonic heating event during the Cretaceous, cuticles are not
preserved. The flora is particularly diverse in ferns (14 species) and fern-like fronds (23 species), whereas
bryophytes and sphenophytes are rare. The Ginkgoopsida, which includes the so called seed-ferns and ginkgo-like
leaves, are rare (e.g., Rochipteris) to being among the dominant elements (e.g., Dicroidium, Sphenobaiera,
Lepidopteris, Ginkgoites and Kurztiana) of the flora. Cycadophyta are very rare to rare with one species of
Pseudoctenis being common. The Voltzialean conifer Heidiphyllum may occur in monotypic assemblages, as a codominant with the other common conifer Rissikia or with other common species. Among the leaves of uncertain
classification are Taeniopteris, with one common species, and other genera – Nilssonia, Linguifolium, Gontriglossa
and Scoresbya – being rare to very rare.
INTRODUCTION
From a fossil flora perspective the Nymboida Coal Measures are
highly significant as they are the source of the oldest commercial coal
seams in the world following the "coal gap" after the disastrous PermianTriassic extinction events (Retallack et al., 2010). They are also important in having yielded over many years from two previously active
quarries a very rich and diverse Triassic flora. A synthesis of the complete Nymboida megafossil flora is presented here for the first time.
GEOLOGICAL SETTING
The Nymboida Coal Measures (located south-west of the city of
Grafton, in northern New South Wales, Australia) were described and
mapped during a study of the Clarence-Moreton Basin by McElroy
(1963). They are now included in the Nymboida Subbasin (Fig. 1), which
lies unconformably below the Triassic to Late Cretaceous nonmarine
sediments of the Clarence-Moreton Basin (O’Brien et al., 1994). The
Dalmally Basalt, which lies below the Basin Creek Formation and above
the Cloughers Creek Formation, has been radiometrically dated at 237 ±
0.4 Ma (Retallack et al., 1993). Identical megafossil floras lie both above
and below the Dalmally Basalt, thus indicating no significant time interval between the deposition of the two formations (Retallack et al., 1977).
Using the recent time scale presented by Gradstein et al (2012), the age
of the Nymboida Flora falls on the Ladinian-Carnian boundary. Because
the Nymboida flora exhibits closer similarity to the Kaihikuan floras of
New Zealand (Retallack, 1987) rather than the typical Carnian floras of
the Molteno (Anderson and Anderson, 2003) it is best assigned a Ladinian
age.
LOCALITY INFORMATION AND PALAEOGEOGRAPHY
Almost all the described fossil plants of the Nymboida Flora have
been collected from two quarries, which, although 5.3 km apart, are
believed to have had a contemporaneous deposition (Holmes, 2000).
FIGURE 1. Map showing the Nymboida Subbasin as the inferred southernmost
extension of the Esk Trough and the Nymboida District with location of
the fossil-bearing quarries.
297
The sedimentary sequences displayed at both the Coal Mine Quarry
(Fig. 2) and the Reserve Quarry (Fig. 3) represent overbank flooding
events by a large meandering river on an alluvial floodplain with open
stagnant lakes and swamplands. Spring-time flooding from snowmelt on
the highlands of the New England Fold Belt to the west would have
transported large quantities of sediment to the Nymboida Subbasin,
which McElroy (1963) regarded as a ponded environment. The finely
laminated shales in the quarries are an indication of seasonal flooding
events. The irregular layers of coarse sandstone represent either high
water flooding or migration of the main stream across the floodplain. The
various types of preservation of plant material in the sediments indicate
autochthonous to allochthonous deposits. The reconstruction (Fig. 4) of
the Middle Triassic Nymboida flood plain as provided by Retallack
(1977) suggests a wide range of habitats to support a very diverse flora.
Thick beds of gray shales often contain numerous plant roots in situ,
thus indicating fossil soil horizons. The presence of charcoal fragments
in some sandstone beds indicates the occurrence of occasional fires in
upland areas. Analysis of the paleopole position from paleomagnetic
data (Anderson and Anderson, 1983; Scotese, 1994) indicates that the
Nymboida Subbasin was located at ca. 60° S. The proximity of the
Paleo-Pacific Ocean would have had an ameliorating effect on daily and
seasonal temperature fluctuations, thus creating a cool temperate climate, with moisture not a limiting factor. Banks of fossil leaves that
occur on numerous horizons suggest that at least some of the vegetation
FIGURE 2. Coal Mine Quarry, Nymboida. Northeastern face showing
overlying massive sheet sandstone and crevasse splay deeply incised into
thinly bedded gray shales, siltstones, thin coal seams and fossil soil horizons.
FIGURE 3. Reserve Quarry, Nymboida. Northern face with sheet sandstone
overlying thin cyclic beds of sandstone, siltstone and coaly shales.
was deciduous as an adaptation for coping with the low angle of sunlight
and a long period of winter darkness.
THE NYMBOIDA MEGAFOSSIL FLORA
The presence of fossils plants in the Nymboida Coal Measures
was first noted by de Jersey (1958) with later descriptions based on
limited collections by Flint and Gould (1975), Retallack (1977), Retallack
et al. (1977), Herbst (1977), Webb (1983, 2001) and Holmes (1987,
1992).
Since 1966, the senior author and his family have made many
collecting trips to the Nymboida quarries. By 2013, their private collection numbered over 2600 selected slabs with many displaying two or
more fossil plants. This is the most extensive and comprehensive collection derived from two separate but contemporaneous Triassic localities
in Australia. The large quantity of material collected allows for a greater
understanding of the range of variation within a “species” and more
chance of identifying the very rare elements in the flora. However, so
much variation also introduces problems of identifying those fossil species that often show overlapping ranges with previously described species. Another extensive collection of plants from the Gondwana Triassic
is from the Molteno Formation in South Africa by Anderson and Anderson (1983, 1989, 2003, 2008), where they were the first to use paleogamma taxonomy and introduced the term “palaeodeme.” In brief, a
“palaeodeme” is an assemblage of plant remains showing a normal distribution of variation, derived from a single assemblage and from a discrete
lithological unit. Unfortunately this approach is not applicable to the
present Nymboida collections as the fossils have been derived from a
miscellaneous collection of loose blocks dislodged from various horizons
on the working quarry faces. However, the traditional alpha taxonomy,
which works well for small limited collections of fossils, does not suit
large collections showing much diversity in size and form of similar
leaves. As a result leaf forms that show a wide range of variation are here
referred to as “species complexes,” basing the name on a previouslydescribed species that represents the core of the complex.
The descriptive taxonomy of the Holmes collections was commenced with the publication of Part 1 in 2000, which described the
Bryophyta and Sphenophyta (Holmes, 2000) and was followed by eight
other parts describing various sections of the flora (Holmes, 2001a,
2003; Holmes and Anderson, 2005a, b, 2007, 2008, 2010, 2013). Unfortunately, due to a tectonic heating event during the Cretaceous (Russell,
1994), cuticles are not preserved. Descriptions therefore are based on the
gross morphology of the plant material, which is often exquisitely preserved. Research for the above publications has revealed the presence in
the preserved flora of 58 genera, 105 species and another 28 forms that
have insufficient detail preserved for specific identification. Still to be
298
FIGURE 4. Reconstruction of the floodplain of the Nymboida Subbasin during mid Triassic time. From Retallack (1977).
described from the Nymboida collection are a few dispersed ovules and
plant stems showing evidence of seasonal growth. A notable feature in
the Nymboida Flora is the absence of insect leaf damage. A single
undescribed beetle wing is the only evidence of the presence of insects.
A brief review of the Flora is given below, and two slabs showing
typical fossil plants are shown in Figures 5 and 6. A classified list of all
the taxa is provided in Appendix 1 for the two quarries. The classification follows broadly that of Anderson and Anderson (2007). Taxa with
one or two collected specimens are listed as “very rare;” three to ten as
“rare;” and those comprising ca. 1% or more of the collection are regarded
as “common.”
All Type, illustrated and mentioned specimens previously described from the Nymboida collection are housed in the Australian Museum, Sydney, New South Wales.
Bryophyta
Colonies of in situ thalloid plants occur rarely on some bedding
planes. They are most likely liverworts with a simple thallus and radiating branches. In the absence of diagnostic characters, they are listed as
“Thalloid fossil” sp. A and sp. B (Holmes, 2000).
Sphenophyta
Sphenophytes are rare. Horsetail swamp-like deposits, which
occur in many Early and Late Triassic assemblages, are absent in the
Nymboida Flora. Characters observed on occasional leaf-bearing stems
and nodal diaphragms that have been collected have been placed in the
genera Zonulamites and Townroviamites to reflect significant differences
that separate Gondwana and northern hemisphere Middle Triassic
equisetalean genera (Holmes, 2000, 2001b). A unique scrambling or float-
ing sphenophyte Nymbolaria tenuicaulis, with pseudo-verticals of elliptic leaves radiating as bi-symmetrical pairs from slender ribbed stems
was recovered from a thin mud smear below a thick sandstone horizon.
Sphenophyte fertile organs include strobili assigned to cf.
Neocalamostachys sp. A and Nymbotheca verticillata, a stout axis bearing regularly spaced, stem-encircling discs bearing sessile sporangia on
the surface of each disc (Holmes, 2000).
Filicophyta
Fronds and frond fragments of ferns and fern-like plants comprise
ca 25% of the Nymboida collections and are among the most diverse
elements of the flora. Leaf length ranges from a few centimeters
(Micronymbopteris repens) to fronds over three meters long (Rhinipteris
walkomii) and similar to those of some extant tree ferns. Where sporangia-bearing material has been collected the ferns have been described in
genera in the Orders Marattiales with eight species; Filicales with four
species and Osmundales with two species (Holmes, 2001). For some
species, e.g., Osmundopsis scalaris, their morphology is known from
almost complete plants with both fertile and sterile fronds.
Twenty-three morphospecies have been described for forms without attached sporangia or associated fertile structures (Holmes, 2003).
These are regarded as “fern-like foliage.” The largest genera are
Cladophlebis with six species; Nymbiella five species and Nymbopteris
three species. The remaining nine genera are all represented by a single
species.
Umkomasiaceae
At Nymboida the fragmentary or complete forked leaves attributed to Dicroidium in the Family Umkomasiaceae are among the most
299
FIGURE 5. A fossil slab from Coal Mine Quarry showing numerous long leaves of Heidiphyllum elongatum and near the upper right two forked leaves of
Dicroidium odontopteroides. Scale bar is 5 cm long.
FIGURE 6. A fossil slab from Coal Mine Quarry showing one large leaf (beyond the fork) of Dicroidium zuberi, a Sphenobaiera schenkii (upper right) and
a few conifer-like leaves of Rissikia media. Scale bar is 5 cm long.
300
commonly occurring plant remains. The extensive Nymboida collections
reveal a range of intergrading forms that link the morphological characters
attributed to past described “species.” As in modern plants there are
varying degrees of morphological variation within a single species. The
designated “type” may not necessarily represent the midpoint in its
range of variation. The problem is exacerbated in paleobotany where
most taxa are described from dispersed plant organs. Following the taxonomic works on Dicroidium by Retallack (1977), Anderson and Anderson (1983) and others, we endeavored to place well-preserved leaves
into previously published species while acknowledging the intergrading
forms linking each “species.” Thus, in the Nymboida flora most material
of Dicroidium has been placed in five “species complexes” (Holmes and
Anderson, 2005a). The single leaf of D. elongatum has probably been
transported from a drier environment as observed in the Benolong Flora
(Holmes, 1982). It is closely similar in form to the specimens of attached
leaves from the Upper Triassic Ipswich Coal Measures (Anderson et al.,
2008). A problematical frond has been described as ?D. nymboidensis.
The affiliated fertile organs of the Dicroidium foliage are two species of
complete female strobili, Umkomasia distans and U. sessilis (Holmes,
1987), together with dispersed ovules. Also present are incomplete male
strobili and dispersed microsporophylls of Pteruchus.
Peltaspermaceae
Lepidopteris leaves and fragments comprise ca. 3% of plants on
catalogued slabs. They show a great range of variation and have been
described in three “species complexes” with two distinct leaf forms as
new species (Holmes and Anderson, 2005b). The affiliated female
Peltaspermum and male Antevsia are each known only from two incomplete strobili.
Kannaskoppiaceae
Although representatives of this family are rare, six new species
of Rochipteris have been described (Holmes and Anderson, 2005b). The
preservation of two species indicates the foliage is inserted on the stem
either as a close spiral or terminal whorl. The fertile organs Kannaskoppia
(female) and Kannaskoppianthus (male), as occur in the Molteno (Anderson and Anderson, 2003), have not yet been found at Nymboida.
Incertae sedis
Leaves of Kurtziana represent ca. 2% of the catalogued slabs and
are sometimes found as the dominant leaf type on some bedding planes.
They have been placed in two “species complexes” with “K. cacheutensis
complex” being the more common (Holmes and Anderson, 2005b). The
affiliated fertile organs of these leaves are as yet unknown in Gondwana.
Ginkgoaceae
Ginkgoites leaves with four species form ca 2.5% of the Nymboida
collection (Holmes and Anderson, 2007). Leaves of the “Ginkgoites
denmarkensis complex” are very common and variable.
Hamshawviaceae
Sphenobaiera with seven species comprises ca 7.5% of the
Nymboida collection (Holmes and Anderson, 2007). Three of the
Sphenobaiera species are common, with “S. schenkii complex” being
dominant on certain bedding planes. Two pairs of female strobili,
Hamshawvia distichos, affiliated with Sphenobaiera are preserved on
one slab. Two species of the male strobili Stachyopitys are described.
Cycadopsida
True cycad leaves in the Order Cycadales comprise ca 4% of the
total collection (Holmes and Anderson, 2008). The majority of the leaves
are placed in ten species in the genus Pseudoctenis and are very rare to
rare with one species being common. Others are placed in two species of
Ctenis and a form with serrate pinnae in Moltenia sparsispinosa. No
fertile material has been found.
Bennettitopsida
A bennettiatalean form is placed in Halleyoctenis brachypinnata
(Holmes and Anderson, 2008). It is possible that some of the genera
placed in incertae sedis may belong here.
Incertae sedis
Due to the absence of cuticular details or affiliated fertile organs
the taxonomic position of the following material is uncertain. Strap-like
leaves with parallel lateral venation have been placed in two species each
in the genera Nilssonia and Taeniopteris and spatulate forms in two
species of Linguifolium (Holmes et al, 2010). Leaves with variously
anastomosing lateral venation have been placed in four species of the
genus Gontriglossa. An outstanding specimen of G. grandis shows a
terminal branch bearing 10 leaves in a whorl or close spiral (Holmes,
1992; Holmes et al., 2010). A large leaf bifurcating into irregular lobes
was described as a new species (Holmes et al, 2010) in the genus
Scoresbya, whose species were known previously mainly from the Jurassic of the Northern Hemisphere.
Pinopsida
Fragments and complete leaves of the Voltzialean conifer
Heidiphyllum elongatum form ca 1% of the preserved Nymboida flora
and are often found associated with Dicroidium and other commonly
occurring species. However, it also is preserved as monotypic assemblages. During working operations at the Reserve Quarry one such bedding plane of over 300 square meters was exposed, suggesting the autumn leaf fall from a mono-specific deciduous forest. Foliage shoots of
the podocarp Rissikia media are common, often in association with
leaves of Heidiphyllum elongatum. A few Rissikianthus (male) and
Rissikistrobus (female) cones are associated with the foliage shoots but
are lacking in details for specific identification (Holmes and Anderson,
2013).
Gnetopsida
One possible species of Yabeiella has been recorded. However,
probably some of the leaves now placed in incertae sedis, e.g., in the
genus Taeniopteris, will prove to belong here.
CONCLUSIONS
The Nymboida Flora is comparable with the megafloras from the
Middle Triassic Toogoolawah Group of the Esk Trough in the northern
Clarence-Moreton Basin (Walkom, 1924) and the Moolayember Formation of the Bowen Basin (Playford et al., 1982) of Queensland. However,
as the flora from the Esk Trough is in need of a modern update and the
one from Moolayember is based on a limited collection from one locality,
detailed comparisons are difficult. Numerous papers have been published on Gondwana Triassic floras, but in the absence of comprehensive
descriptions of the complete floral assemblages one cannot make useful
comparisons with the Nymboida Flora.
This synthesis of the Nymboida megafossil flora, based on a
series of nine descriptive taxonomic papers, provides the first comprehensive account of a Triassic fossil flora in Australia in the twenty-first
century. Furthermore, the Nymboida Coal Measures are highly significant as they are the source of the oldest commercial coal seams in the
world following the "coal gap" after the disastrous Permian-Triassic
extinction events. Continuous collection from the once active quarries,
over some 40 years, has yielded an extensive range of the common leaves
and many of the rare elements of the flora. To date a total of 58 genera,
105 species and 28 forms have been described. The common genera such
as Asterotheca, Cladophlebis, Dicroidium, Sphenobaiera, Lepidopteris,
301
Ginkgoites, Kurztiana, Pseudoctenis, Heidiphyllum, Rissikia and
Taeniopteris are found in other Gondwana Triassic floras, but many of
their species are unique and among the very rare finds they are often the
only occurrence known in the world.
ACKNOWLEDGMENTS
We thank Spencer Lucas, Greg Retallack and Lawrence Tanner for
comments on an earlier version of the manuscript.
REFERENCES
Anderson, J.M., and Anderson, H.M., 1983, Palaeoflora of southern Africa.
Molteno Formation (Triassic).Vol.1. Part 1. Introduction. Part 2.
Dicroidium: Balkema, Rotterdam, 227 p.
Anderson, J.M., and Anderson, H.M., 1989, Palaeoflora of southern Africa.
Molteno Formation,(Triassic).Vol. 2: Gymnosperms (excluding
Dicroidium): Balkema, Rotterdam, 567 p.
Anderson, J.M., and Anderson, H.M., 2003, Heyday of the Gymnosperms:
Systematics and biodiversity of the Late Triassic Molteno fructifications: Strelitzia, v. 15, p. 1-398.
Anderson, H.M., and Anderson, J.M., 2008, Molteno Ferns: Late Triassic
biodiversity in southern Africa: Strelitzia, v. 21, p. 1-258.
Anderson, J.M., Anderson, H.M., and Cleal, C.J., 2007, Brief history of the
gymnosperms: Classification, biodiversity, phytogeography and ecology: Strelitzia, v. 20, p. 1-280.
Anderson, H.M., Holmes, W.B.K., and Fitness, L.A., 2008, Stems with
attached Dicroidium leaves from the Ipswich Coal Measures, Queensland,
Australia: Memoirs of the Queensland Museum, v. 52(2), p. 1-12.
Archangelsky, S., 1968, Studies on Triassic fossil plants from Argentina. 4.
The leaf genus Dicroidium and its possible relation to Rhexoxylon stems:
Palaeontology, v. 11, p. 500-512.
De Jersey, N.J., 1958, Macro- and micro-floras of north-eastern New South
Wales: Journal and Proceedings of the Royal Society of NSW, v. 92(14), p. 83–89.
DuToit, A.L., 1927, The fossil flora of the Upper Karoo Beds: Annals of the
South African Museum, v. 22, p. 289-420.
Flint, J.C.E., and Gould, R.E., 1975, A note on the fossil megafloras of the
Nymboida and Red Cliff Coal Measures, southern Clarence-Moreton
Basin: Journal and Proceedings of the Royal Society of NSW, v. 108, p.
70-74.
Florin, R., 1936, Die Fossilen Ginkgophyten von Franz-Joseph-Land nebst
Eröretungen über vermeinliche Cordaitales mesozoischen Alters:
Palaeontologia Band, v. 81-82, p. 71-173.
Frenguelli, J., 1946, Contribuciones al conocimiento de la flora del Gondwana
superior en la Argentina. 33. Ginkgoales de los estratos de Potrerilles en
la Precordillera de Mendoza: Notas de Museo de la Plata. Palaeontologia,
v. 87, 11, p. 101-127.
Gradstein, F.M., Ogg, J.G., Schmitz, M.D., Ogg, G.M., 2012, A Geologic
Time Scale 2012: Elsevier, Amsterdam, 2: 1-1144.
Herbst, R., 1977, Sobre Marattiales (Filicopsida) Triasicas de Argentina y
Australia. Parte 2. Los generous: Danaeopsis y Reinitzia: Ameghinina,
v. 14, p. 19-32.
Holmes, W.B.K., 1987, New corystosperm ovulate fructifications from the
Middle Triassic of eastern Australia: Alcheringa, v. 11, p. 165-173.
Holmes, W.B.K., 1982, The Middle Triassic flora from Benolong, near
Dubbo, central-western New South Wales: Alcheringa, v. 11, p. 165-173.
Holmes, W.B.K., 1992, Glossopteris like leaves from the Triassic of eastern
Australia: Geophytology, v. 22, p. 119-125.
Holmes, W.B.K., 2000, The Middle Triassic megafossil flora of the Basin
Creek Formation, Nymboida Coal Measures, New South Wales. Part 1.
Bryophyta, Sphenophyta: Proceedings of the Linnean Society of NSW,
v. 122, p. 43-68.
Holmes, W.B.K., 2001a, The Middle Triassic megafossil flora of the Basin
Creek Formation, Nymboida Coal Measures, New South Wales. Part 2.
Filicophyta: Proceedings of the Linnean Society of NSW, v. 123, p. 3987.
Holmes, W.B.K., 2001b, Equisetalean plant remains from the Early to
Middle Triassic of New South Wales, Australia: Records of the Australian
Museum, v. 53(1), p. 9-20.
Holmes, W.B.K., 2003, The Middle Triassic megafossil flora of the Basin
Creek Formation, Nymboida Coal Measures, New South Wales. Part 3.
Fern-like foliage: Proceedings of the Linnean Society of NSW, v. 124, p.
53-108.
Holmes, W.B.K., and Anderson, H.M., 2005a, The Middle Triassic megafossil
flora of the Basin Creek Formation, Nymboida Coal Measures, New
South Wales. Part 4. Dicroidium: Proceedings of the Linnean Society of
NSW, v. 126, p. 1-37.
Holmes, W.B.K., and Anderson, H.M., 2005b, The Middle Triassic megafossil
flora of the Basin Creek Formation, Nymboida Coal Measures, New
South Wales. Part 5. The Genera Lepidopteris, Kurtziana, Rochipteris
and Walkomiopteris: Proceedings of the Linnean Society of NSW, v.
126, p. 39-79.
Holmes, W.B.K., and Anderson, H.M., 2007, The Middle Triassic megafossil
flora of the Basin Creek Formation, Nymboida Coal Measures, New
South Wales. Part 6. Ginkgophyta: Proceedings of the Linnean Society
of NSW, v. 128, p. 155-200.
Holmes, W.B.K., and Anderson, H.M., 2008, The Middle Triassic megafossil
flora of the Basin Creek Formation, Nymboida Coal Measures, New
South Wales. Part 7. Cycadophyta: Proceedings of the Linnean Society
of NSW, v. 129, p. 113-140.
Holmes, W.B.K., and Anderson, H.M., 2013, The Middle Triassic megafossil
flora of the Basin Creek Formation, Nymboida Coal Measures, New
South Wales, Australia. Part 9. The genera Heidiphyllum, Voltziopsis,
Rissikia and affiliated cones and Yabiella: Proceedings of the Linnean
Society of NSW, v. 134.
Holmes, W.B.K., Anderson, H.M., and Webb, J.A., 2010, The Middle Triassic megafossil flora of the Basin Creek Formation, Nymboida Coal
Measures, New South Wales. Part 8. The genera Nillsonia, Taeniopteris,
Linguifolium, Gontriglossa and Scoresbya: Proceedings of the Linnean
Society of NSW, v. 131, p. 1-26.
McElroy, C.T., 1963, The Geology of the Clarence - Moreton Basin: Memoir Geological Survey N.S.W. Geology, v. 9, p. 1-172.
O’Brien, P.E., Korsch, S.J., Wells, A.T., Sexton, M.J., and Wake-Dyster,
K.D., 1994, Structure and tectonics of the Clarence-Moreton Basin:
Australian Geological Survey Organisation Bulletin, v. 241, p. 195-216.
Oishi, S., 1931, On Fraxinopsis Weiland and Yabeiella gen. nov.: Japanese
Journal of Geology and Geography, v. 8, p. 259-267.
Playford, G., Rigby, J.F., and Archibald, D.C., 1982, A Middle Triassic flora
from the Moolayember Formation, Bowen Basin, Queensland: Geological Survey of Queensland Publication, v. 380, p. 1-52.
Retallack, G.J., 1977, Reconstructing Triassic vegetation of eastern Australia: a new approach for the biostratigraphy of Gondwanaland: Alcheringa,
v. 1, p. 247-278, Alcheringa Fiche, v. 1, G1-J16.
Retallack, G.J., 1987, Triassic vegetation and geography of the New Zealand
portion of the Gondwana supercontinent; in Elliot, D.H., Collinson,
J.W., McKenzie, G.D., and Haban, S.M., eds., Gondwana six; stratigraphy and paleontology: American Geophysical Union, Geophysical Monograph, 41, p. 29-39.
Retallack, G.J., Gould, R.E., and Runnegar, B., 1977, Isotopic dating of a
Middle Triassic megafossil flora from near Nymboida, north-eastern
New South Wales: Proceedings of the Linnean Society of NSW, v. 101,
p.77-113.
Retallack, G.J., Renne, P.R., and Kimbrough, D.L., 1993, New radiometric
ages for Triassic floras of south-eastern Gondwana: New Mexico Museum Natural History Science, Bulletin 3, p. 415-418.
Retallack, G.J., Sheldon, N.D., Carr, P.F., Fanning, M., Thompson, C.A.,
Williams, M.L., Jones, B.G., and Hutton, A., 2010, Multiple Early Triassic greenhouse crises impeded recovery from the Late Permian mass
extinction: Palaeogeography, Palaeoclimatology and Palaeoecology, v.
308, p. 233-251.
302
Russell, N.J., 1994, A palaeothermal study of the Clarence-Moreton Basin:
Australian Geological Survey Organisation Bulletin, v. 241, p. 237-276.
Scotese, C.R., 1994, Early and Late Triassic palaeographic maps; in de
Kleinig, V., ed., Pangea: Palaeoclimate, tectonics and sedimentation
during accretion, zenith and breakup of a super continent: Geological
Society of America, Special Paper 288, p. 7.
Townrow, J.A., 1967, On Rissikia and Mataia, podocarpaceous conifers
from the Lower Mesozoic of southern lands: Papers and Proceedings of
the Royal Society of Tasmania, v. 101, p. 103-136.
Walkom, A.B., 1917, Mesozoic floras of Queensland. Pt. 1. The flora of the
Ipswich and Walloon Series. (d) Ginkgoales, (e) Cycadophyta, (f)
Coniferales: Publications of the Geological Survey of Queensland, v.
259, p. 1-49.
Walkom, A.B., 1924, On fossil plants, near Bellevue, Esk: Queensland
Museum Memoir, v. 8, p. 77-92.
Webb, J.W., 1983, A new plant genus, possibly a marattialean fern, from the
Middle Triassic of eastern Australia: Memoirs Association Australasian
Palaeontology, v. 1, p. 363-371.
Webb, J.W., 2001, Marantoidea acara sp. nov., a new marattialean fern
from the Middle Triassic of eastern Australia: Proceedings of the Linnean Society of NSW, v. 123, p. 215-224.
303
APPENDIX
A classified list of the plant taxa from the Nymboida Coal Mine and Reserve.
304
305