The Middle Triassic Megafossil Flora of the Basin Creek Formation, Nymboida Coal Measures, New South Wales, Australia. Part 6. Ginkgophyta

2007·20.6 MB·English

by  Wbkeith Holmes

The Middle Triassic Megafossil Flora of the Basin Creek
Formation, Nymboida Coal Measures, New South Wales,
Australia. Part 6. Ginkgophyta
W.B.Keith Holmes' and Heidi M.Anderson^
'46 Kurrajong Street, Dorrigo, NSW, 2453, Australia (Hon. Research Fellow, University ofNew
England,Armidale, NSW, 2351); M6 Kurrajong Street, Dorrigo, NSW. 2453,Australia (Hon. Palaeobotanist,
SouthAfrican National Biodiversity Institute, Pretoria 0001 SouthAfrica).
Holmes, W.B.K. andAnderson, H.M. (2007). The Middle Triassic Megafossil Flora ofthe Basin Creek
Formation,NymboidaCoal Measures, New South Wales,Australia. Part 6. Ginkgophyta. Proceedings of
theLinnean SocietyofNewSouth Wales 128, 155-200.
The Ginkgophyte Flora from two quarries in the Basin Creek Formation of the Middle Triassic
NymboidaCoalMeasuresofnortheasternNSWAustraliaisdescribedandillustrated.Thisincludesthefirst
record fromAustralia ofHamshawvia, a female strobilusbearing apair ofmegasporophylls. Hamshawvia
and the male strobilus Stachyopitys are regarded as the fhictifications ofthe plants bearing Sphenobaiera
leaves.TwooftheHamshawviaspecimensareplacedinH. distichossp.nov. andathirdinH. sp.A. Several
specimens of Stachyopitys sfrobili are compared with S. matatilongus and S. lacrisporangia from the
MoltenoFormationofSouthAfrica. The Ginkgophyte leavesformc. 10% ofthecollectedleaffossils from
the Nymboida localities and are placed in the genera Ginkgoites (four morpho-species) and Sphenobaiera
(eight morpho-species). In the absence of preserved cuticle the morpho-species are differentiated on
characters ofgross morphology. Infive cases where sufficient specimens ofaparticularform are available
to indicate a natural range ofvariation they are placed in a 'morpho-species complex'. New leaftaxa are
themorpho-species Ginkgoitesnymboidensis sp. nov.,Sphenobaierapaucinervasp. nov.,S. densinervasp.
nov. andS. nymbolinea sp. nov.
Manuscriptreceived 9 February 2006, accepted forpublication 13 December2006.
KEYWORDS: Ginkgoites, Ginkgophyta,Hamshawvia, Nymboida Coal Measures, Sphenobaiera
fioictifications, Stachyopitys, Triassic Flora.
INTRODUCTION
2005b) with the genus Lepidopteris and its affiliated
fructifications Peltaspermum and Antevsia, and the
Inthis sixthpartofthe series describingthe early generaKurtziana, Rochipteris and Walkomiopteris.
Middle Triassic Nymboida Flora, leaves assigned to
theGinkgophytegeneraGinkgoitesandSphenobaiera
and the affiliated fertile organs Stachyopitys and GINKGOPHYTA-A SHRINKING LINEAGE.
Hamshawvia are illustrated and described. This
is the first description of the female Ginkgophyte The Ginkgophytes have a long evolutionary
megasporophyll Hamshawvia fromAustralia. history ranging from the Carboniferous to the present
Part 1 (Holmes 2000) ofthis series dealtwith the (Taylor and Taylor 1993; Holmes 1996). However
Bryophyta and Sphenophyta; Part 2 (Holmes 2001) some early species are known only as isolated
with the Filicophyta; Part 3 (Holmes 2003) with fern- specimens and their affinities are questionable
likefoliage;Part4(HolmesandAnderson2005a)with (Taylor and Taylor 1993; Rothwell and Holt 1997).
the genusDicwidium and its fertile organs Pteruchus From the Late Palaeozoic to the early Tertiary the
and Umkomasia; Part 5 (Holmes and Anderson Ginkgophyta had an almost global distribution with
TRIASSIC FLORA FROM NYMBOIDA GINKGOPHYTA
-
a peak of diversity in the late Mesozoic and early contrasts with that of the Benolong Flora in the
Tertiary (Zhou 1997; Rothwell and Hoh 1997). The Napperby Formation near Dubbo, Australia,
last recorded occurrences in Gondwana are from the (Holmes 1982) where Sphenobaiera leaves are the
EoceneofArgentina(Berry 1938) andthePalaeogene most numerous of the preserved plant remains. In
of Tasmania (Hill and Carpenter 1999). It has been their collections of fossil plants from the Molteno
suggested that the fleshy Ginkgo fruits were ingested Formation of South Africa, Anderson and Anderson
by herbivore dinosaurs that acted as dispersal agents (1989) noted that leaves of Sphenobaiera were the
fortheseeds.Theextinctionofthedinosaursattheend second most common taxon with a mean abundance
oftheCretaceousmayhaveresultedinthecontraction of 30%) in 32 assemblages. Fertile organs attributed
in both range and diversity throughout the Tertiary to the Ginkgophyta are extremely rare in the fossil
thatbrought Ginkgo to the brink ofextinction (Tralau record.
1968). Today the last single extant representative is Leaves from a single plant ofthe extant Ginkgo
Ginkgo biloba which may no longer exist in the wild biloba may exhibit a great amount ofvariation which
(Li 1956) but is now cultivated almost world-wide. pointstotheprobabilityofasimilarrangeofvariation
Previous Gondwana Triassic records of infossilGinkgophyteleaves(Walkom 1917).Thusthe
Ginkgophyta include: from Australia - Tenison identification to species level ofGinkgophyte leaves
Woods (1883), Ratte (1887, 1888), Johnston (1888), fromlargeassemblageswithawiderangeofvariation
Shirley (1887, 1898), Dun (1909), Walkom (1917, andintergradingformsraisesproblemssimilartothose
1924, 1928),Retallack(1977), Retallacketal. (1977), experienced with the Dicroidium genus (Holmes and
Holmes (1982, 1996); from South Afiica - Seward Anderson 2005a) andtheLepidopteris andKurtziana
(1903, 1908), DuToit (1927, 1932), Baldoni (1980), genera (Holmes andAnderson 2005b). Anderson and
Anderson and Anderson (1983, 1985, 1989, 2003); Anderson (1989) notedthatattheirMolteno localities
from South America - Frenguelli (1946), Menendez Matl11 andBirl11 threemorphotaxaofSphenobaiera
(1951), Artabe (1985), Azcuy and Baldoni (1990), formed a complex and intergrading series. Harris
-
Gnaedinger and Herbst (1999); from Malagasy et al. (1974) also recognised that leaves of the
Carpentier (1935) and from India-Pal (1984). Ginkgoales in the Yorkshire Flora varied greatly in
form and that specific distinction was difificult. They
suggested that differences within a local assemblage
and between assemblages could arise from a slight
METHODS
peculiarity of genetic balance between populations
of trees or by the envirormient. Zhou (1997) also
The material described in this paper is based noted that almost all species that have been studied
mainly on collections made by the senior author in some detail exhibit a rather wide spectrum ofleaf
and his family from two Nymboida quarries over a variation. The fossilplants atNymboida come from a
period of forty years and on limited material held range offacies that represent different environments
in the fossil collections of the Australian Museum, so it is probable that some ofthe variation within the
Sydney, and also those in the Geology Department of Nymboida leafcomplexes may have been influenced
the University ofNew England, Armidale, as noted by environmental conditions.
in Retallack (1977) and Retallack et al. (1977). The Harris (1935) believedthat cuticulardetails were
Nymboidamaterialwas collectedmostly fromblocks essential for specific determination of Ginkgoites.
fallen from the working quarry faces so the exact Anderson and Anderson (1989) noted that their
horizon or source ofmost specimens is uncertain. Sphenobaiera and Ginkgo (= Ginkgoites) cuticles
Details of the Coal Mine Quarry and Reserve appeared to share a more or less equal number of
Quarrytogetherwitha summaryofthe geologyofthe features inthe epidermal structure andalsowiththose
BasinCreekFormation,theNymboidaCoalMeasures of the genera Lepidopteris and Dejerseya. At the
and the Nymboida Sub-Basin were provided in Nymboida localities all cuticle has been destroyed in
Holmes (2000). An earlier study by McElroy (1962) a heating event during the Cretaceous (Russel 1994).
of the Clarence-Moreton Basin included the older Due to the absence of cuticle in any of our
geological units now regarded as formations within otherwise well-preserved plant material the
the Nymboida Sub-Basin. identification ofleaves is based on features ofgross
In the Holmes Nymboida collection, leaves morphology; e.g. size and form of lamina; angle of
attributed to the Ginkgophyta comprise c. 10% of divergence ofthe lamina from the base; form ofthe
the c. 2600 catalogued specimens with Ginkgoites petiole; natureofthe segmentationandveindensityin
forming c. 2.5% and Sphenobaiera c. 1.5%. This distalportionsofthelamina. Incaseswherenumerous
156 Proc. Linn. Soc. N.S.W., 128, 2007
W.B.K. HOLMES AND H.M. ANDERSON
specimens ofa somewhat similar form are available Description
this variation is encompassed in our identification of A medium-sized Ginkgoites leaf with elegant
mm
the group as a 'morpho-species complex'. Leaves semicircular leaves, 75-100 long, 90-140
mm
with a fan-shaped lamina (flabbelate) and a distinct wide; basal angle 180°-200°; petiole slender,
petiole are placed in Ginkgoites. Wedge-shaped 3mm wide, length unknown; lamina symmetrically
leaves (cimeate) contracting to a petiolate-like base dissectedalmosttothebaseintosixprimarysegments;
are placed in Sphenobaiera. This differentiation is each segment again incised from % to Vi to the base;
partly subjective and certain leaves could equally ultimate lobes parallel-sided or elongate-spathulate,
mm
well be placed in Ginkgoites orSphenobaiera. 6-12 in width, the irmer segments longer than
Based on the presence ofassociated or attached the outside segments; apicesrounded-obtuse orrarely
fertile material in their large Molteno Formation shallowly notched; veins forking in proximal portion
collections, Anderson and Anderson (2003) have ofprimarysegmentsthenrunningstraightandparallel
placed Ginkgoites and Sphenobaiera leaves in to the apical margin; vein density in the distal region
separate Families and Classes. In the absence ofany ofthe segments 12-14/10 mm.
leaves attachedto fertile organs atNymboidawehave
not placed our morpho-taxa above generic rank. Holotype
The Ginkgophytes were widespread in the AMF129928. Australian Museum, Sydney.
Northern Hemisphere during the early Mesozoic
and some northern morpho-taxa are closely similar Type locality
in gross morphology to individuals in the Nymboida Coal Mine Quarry, Nymboida. Basin Creek
flora. However, due to problems relating to time and Formation, Nymboida Coal Measures, early Middle
geographic separation we have made comparisons Triassic.
only with Gondwana material.
The flabellate leaves of the Rochipteris genus Other material
(Gnaedinger and Herbst 1998, Baroime-Nugent AMF129926-7,AMF130170,CoalMineQuarry;
AMF
et al. 2003, Holmes and Anderson 2005b) and the 129929, Reserve Quarry.
leaves associated with Kannaskoppia (Anderson
and Anderson 2003) may be confused with the Discussion
ginkgophytes. They are differentiated by the usually This uncommon morpho-taxon bears some
asymmetrical dissection of the lamina, the more features with the leaf illustrated by Tenison-Woods
delicate venation with anastomoses and by their (1883, pi. 4, fig. 3) as Jeanpaulia bidens. While that
distinct stomata. specimen is somewhat similar in dissection pattern
The typesandall illustratedmaterial inthispaper and shape of the lobes and general proportions it is
have been allocated AMF numbers and are housed smaller andtoo poorlypreservedto make meaningful
in the Palaeontology Department of the Australian comparisons. The leaves identified by Shirley (1897,
Museum, Sydney. pi. 6, figs 1,2; 1898, pi.19, fig. 1, pi. 21) as Baiera
{Jeanpaulia) bidens and by Walkom (1917, pi. 3,
fig. 1) as Baiera bidens, differ from Tenison-Woods
SYSTEMATIC PALAEOBOTANY specimenby the lamina being incisedto the base into
linearsegments, eachofwhichis againincisedalmost
Order Ginkgophyta tothebasetoformelongatednarrowelliptic segments
with acute apices. Walkom's specimen was selected
Genus Ginkgoites Seward 1919 as the type for Ginkgo denmarkensis by Anderson
and Anderson (1989). Ginkgoites waldeckensis
Ginkgoites nymboidensis Holmes andAnderson (Anderson and Anderson 1989), Gnaedinger and
sp. nov. Herbst (1999) and Ginkgoites koningensis Anderson
Figures 1 A,B; 2A,B. and Anderson (1989, 2003) are closely similar in
lamina shape to Ginkgoites nymboidensis but differ
Diagnosis by their much denser venation. G. matatiensis
Leaf lamina semicircular, elegantly dissected Anderson and Anderson (1989) differs by the four
almost to base into six primary elongated narrow- secondary segments on either side of the median
elliptic to spathulate segments, each segment again cleft. G. semirotunda Holmes (1982) is smaller and
deeply to shallowly incised, apices rounded. with a slightly different dissection of the lamina.
Ginkgo palmata (Ratte) Anderson and Anderson
Proc. Linn. Soc. N.S.W., 128, 2007 157
TRIASSIC FLORAFROM NYMBOIDA GINKGOPHYTA
-
1989, which includes G. simmondsii Shirley (1898) G. denmarkensis selectedbyAnderson andAnderson
and Baiera simmondsii (Shirley) Walkom 1917, (1989 p. 227) in which each of the six primary
differs from Ginkgoites nymboidensis by the greater lobes is dissected halfway or more to the base to
number of primary segments and denser venation. form elongated parallel-sided to slightly expanding
G. nymboidensis is similar to some forms of G. secondary lobes contracting distally to an acute apex.
denmarkensis(Fig. 3B)butdiffersbyitssemi-circular Some forms e.g. Fig. 3B are closeto G. nymboidensis
lamina and elegantpartially dissected segments. but are less elegantly symmetrical and with deeper
incisions ofthe secondary lobes. The very large leaf
(Fig. 4A) is close in form to the Molteno leaf G.
'Ginkgoites denmarkensis Anderson and aviamnicathatdiffersbythelessdensevenation(6/10
Anderson 2003 complex' mm). Forms with less deep incisions and broadening
Figures 3A,B; 4A; 5A,B; 6A; 7A; 8A. ofthe primary lobes (Figs 5A,B, 6A, 7A, 8A) thatwe
haveincludedinthiscomplexareclosetotheMolteno
Holotype G. matatiensis which differs by the dissection into
University ofQueensland F1411, Denmark Hill, eight primary segments. The fragmentary leaves
Ipswich Coal Measures, Queensland. figured by Gnaedinger and Herbst (1999, figs 4b,
5D-F) as Ginkgoites sp. fromtheTranquilo Group of
Selected references Patagonia are closely similar in outline and venation
1917 Baiera bidens, Walkom, pi. 3, fig. (2). to G. denmarkensis.
1965 Ginkgo digitata. Hill et al. pi. T9, fig. 6.
1965 Ginkgoites simmondsii. Hill et al., pi. T
XI, fig. 3. Ginkgoitesginkgoides (Shirley 1898) Florin 1936.
1965 Ginkgoitesginkgoides. Hill et al., pi. TXI, Figures 9A,B
fig.5.
1989 Ginkgo denmarkensis, Anderson and Type specimen
Anderson p.227, t. fig. 2, pi. 322. F104c Queensland Geological Survey, Denmark
1999 1Ginkgoites sp., Gnaedinger and Herbst, Hill, Ipswich Coal Measures, Queensland.
p. 285, figs 4B, 5D-F.
2003 Ginkgoites denmarkensis, Anderson and Selected references
Anderson, p.197, t. fig. 3. 1898 Baieraginkgoides Shirley, p. 13, pi. 3,
fig. 1.
Description 1917 Baieraginkgoides Walkom, p. 12, pi. 3,
Medium to large flabbelate leaves with a long figs 3,4.
mm mm
slender to strong petiole to 40 long, 2-A
mm mm
wide; lamina 100-170 long, 100-200 wide; Description
basal angle 140°-270°; divided into six primary Medium-sized incomplete Ginkgoites leaves
segments that range in form from those divided from divided into four to six widely separated primary
% from apex to almost to the base to form elongated segments attenuated basally, expanding distally;
mm
almostlinearornarrow spathulate segmentsthattaper apices not known; petioles stout, to 6 wide,
distally to acute or rounded apices (Figs 3A,B, 4A), length not known; veins prominent, density c. 10-
to other forms where the primary segments become 12/10 mm.
broad-elliptical with entire, notched or shallowly
incised apices (Figs 5A,B, 6, 7, 8A). Veins fork near Material
the base then run straight and parallel to the apex of AMF129941-2, Coal Mine Quarry.
mm
the lobes; density in the distal portion 12-14/10
and in rare specimens to 16-18/10 mm. Discussion
These rare specimens have close similarities
Material with those illusfrated by Shirley (1898) and Walkom
AMF129930-i, 129936-7, Coal Mine Quarry; (1917). At Nymboida they occur in allocthonous
AMF129935, Reserve Quarry. deposits ofmostly macerated plant fragments. These
Discussion specimens are probably decorticated or decaying
Leaves in the 'G. denmarkensis complex' are leaves and could possibly have been derived from G.
common and variable. Some leaves from Nymboida denmarkensis trees.
(Fig. 3A) are closely similar to the type specimen of
158 Proc. Linn. Soc. N.S.W., 128, 2007
HOLMES AND ANDERSON
W.B.K. H.M.
Ginkgoites sp. cfG. waldeckensis (Anderson shapedleaves contractedbasally intoastoutpetioleto
mm mm
andAnderson 1989) Gnaedinger and Herbst 1999 6 wide and 50-60 long; angle ofdivergence
mm
Figures 8B-D. from 50°-80°; lamina from 110-150 long and to
mm
140 wide; deeply incised to form 4 to 6 major
Description segments, each segment again shallowly incised to
Small Ginkgoites leaves, lamina semicircular to form up to 12 ultimate, parallel-sided segments with
mm mm
flabbelate,25-35 long,35-45 wide;petiole 1 rounded apices; density ofvenation in distal portion
mm long, 1-1.5 mmwide with an expandedleafbase: ofsegments c. 10/10 mm.
lamina diverging from base at an angle of 130°-180°,
deeply incised to form six major segments, each Material
AMF AMF
segment again less deeply incisedto form 12 terminal 129943 and counterpart 129947,
lobes with truncate or shallowly notched apices; each AMF129953,AMF121025-6,AMF130169, all Coal
lobe has from four to six veins giving a vein density Mine Quarry; AMF130168, Reserve Quarry.
in apical portions ofc. 16-24/10 mm.
Discussion
Material TheNymboidamaterial assignedto this complex
AMF129938, 129940, Coal Mine Quarry; is relatively common. The leaves are close to S.
AMF129939, Reserve Quarry. stormbergensis fromthe Molteno Formation ofSouth
Africa but sometimes differ by the presence of a
Discussion stout variously elongated petiolate base. S. coronata
The rare semi-circular, deeply segmented leaves Anderson and Anderson, also from the Molteno
of this morpho-species differ from any previously Formation, has a similar density ofvenation andmay
figured species from Australia. The few Nymboida be stoutlypetiolatebutdiffersbyabroaderdivergence
specimens are similar in lamina size and outline to and more irregular incisions of the lamina. S.
some forms ofthe variable Ginkgoites waldeckensis stormbergensis differs fromS. densinerva (below) by
from the Moltenon Formation of South Africa the less dense venation. The woody interveinal striae
(Anderson and Anderson 1989) but the long slender noted by Retallack et al. (1977) in a leaf fragment
petioles have not been observed. The leaves from referred to S. stormbergensis from Cloughers Creek
the El Tranquilo Group of Patagonia placed by near Nymboida, have not been observed in material
Gnaedinger and Herbst (1999) in G. waldeckensis from the Coal Mine and Reserve Quarries.
are larger in size and divided four or five times into
narrow linear segments with finervenation.
Sphenobaierapaucinerva Holmes andAnderson
sp. nov.
Genus Sphenobaiera Florin 1936 Figures lOB, 14A-D
''Sphenobaiera stormbergensis (Seward 1903) Diagnosis
A
Frenguelli 1948 complex' small Sphenobaiera leaf; lamina with deep
Figures lOA; 11A,B; 12A,B; 13A central incision, lateral segments again less deeply
incised to form four parallel-sided segments with
Holotype distal margins acute, rounded or shallowly cleft;
Baiera stormbergensis Seward 1903, F11670 density ofvenation in distal portion of segments 6-
SouthAfrican Museum 10/10 mm.
Selected references Description
mm
1903 Baiera stormbergensis Sewardfig.8(3). Small wedge-shaped leaves; lamina 60-85
mm
1924 Biera bidens Walkom pl.21, fig.2. long, 45-80 wide, contracting basally into a
mm mm
1989 SphenobaierastormbergensisAnderson stout petiole 3 wide, to 20 long. Angle of
andAnderson p.146, pl.91, pi.100, figs 9, 18. divergence oflaminafrombase 60°-80°. Laminawith
1999 Sphenobaierastormbergensis Gnaedinger deep medial incision; lateral pair of segments each
andHerbstfig.il D,E. incisedto a depth ofc. 1/3 from distal margin to form
four equal or irregular segments with sub-parallel
Description margins and acute to rounded, notched or shallowly
A
medium-sized Sphenobaiera with wedge- incised tips. Venation coarse, bifiircating proximally
Proc. Linn. Soc. N.S.W., 128, 2007 159
TRIASSIC FLORA FROM NYMBOIDA GINKGOPHYTA
-
and then running parallel to distal margin, density in lobes (Figs 17A, 18C), others withbroad less incised
distal portion c. 6-10/10 mm. laminae (Fig. 20A,B). Apices of segments truncate
or broadly obtuse. Veins bifurcating only in basal
Holotype portion of the lamina and then running straight and
AMF129954, Australian Museum, Sydney. parallel tothe apical margin; density ofveins indistal
portion ofthe lobes from 16-24/10 mm.
Type locality
Coal Mine Quarry, Nymboida. Basin Creek Holotype
Formation, Nymboida Coal Measures, early Middle AMF129945 and counterpartAMF129949.
Triassic.
Type locality
Other material Coal Mine Quarry, Nymboida. Basin Creek
AMF129944, AMF129955-7, Coal Mine Formation, Nymboida Coal Measures, early Middle
Quarry. Triassic.
Name derivation Name derivation
paucinerva-referring to the less dense venation densinerva - referring to the more dense
than inthe somewhat similar-shaped smallerforms of venation when compared with most other Nymboida
leaves placed in S. densinerva below. ginkgophyte material.
Discussion Other material
S. paucinerva is an uncommon element in the AMF129959-68, 129971-2, Coal Mine Quarry;
Nymboida collection. The leaves ofS. insecta and S. AMF129969, Reserve Quarry.
helveticafromtheMoltenoFormationofSouthAfrica
(Anderson and Anderson 1989) are divided into four Discussion
segments withrounded apices. Howeverboth species Our illusfrations represent what we consider
are significently larger than S. paucinervia and have to be the range of variation of the abundant leaves
preserved and described cuticles. S. paucinervia within this complex, from smallest to largest leaves.
may be a small form of the much larger leaved S. The smaller leaves of5. densinerva(Figs 15A-D) are
stormbergensis but there are no intermediate forms distinguished from the less variable S. paucinerva
in our collection. (Figs 14A-D) essentiallybythe denservenation. The
larger leaves of S. densinerva (Figs 18B-E) differ
from S. stormbergensis by the more parallel strap-
'SphenoAa/era densinerva Holmes andAnderson like segments and by the much denser venation. The
sp. nov. complex' distal portion ofthe very large leafin Figure 17A is
Figures IOC; 15A-D; 16A,B; 17A-C; 18A-D; 19A; closely similar in form but very much larger than
20A,B. the incomplete specimen of Baiera ipsviciensis of
Shirley (1898 pi.12, fig.2) and repeated in Walkom
Diagnosis (1917pl.4,figsl,2)
A
small to large petiolate cuneate leaf divided
into four short primary truncate segments or with
longer parallel-sided or slightly expanding segments ^Sphenobaiera schenckii (Feistmantel 1889) Florin
sometimes again shallowly incised; apices truncate or 1936 complex'
broadly obtuse; venation density in distal portion of Figures 21A-E; 22A-D; 23A-D.
segments c. 16-24/10 mm.
Lectotype
Description Baiera schencki Feistmantel 1889, pi. 3, fig. 2.
A
very variable cuneate leafranging from small (seeAnderson andAnderson 1989)
mm mm
to large; lamina 60-130 long, 40-100 wide;
diverging at 45°-80° from a well-defined slender Selected references
mm mm
to stout petiole 10-30 long, 1.5^ wide. 1889 Baiera SchenckiFeistmantel, pi. 3, fig 2.
Lamina dividedby deep incisions into foursegments. 1989 Sphenobaiera5c/ze«cA:n'Anderson and
Some largerleaves have longer segments that maybe Anderson, p. 142, pis 57, 58, 79.
again incised to form further parallel-sided ultimate 2003 Sphenobaieraschenckii Anderson and
Anderson, pp 211, 223.
160 Proc. Linn. Soc. N.S.W., 128, 2007
HOLMES AND ANDERSON
W.B.K. H.M.
mm
Description long, c. 40 wide, diverging at c. 30° from a short
Asmall Sphenobaiera leafbisected almostto the stout petiolate base 5-20 mm long, 0.3-4 mm wide.
base and each segment then symmetrically twice less Laminawith shallowto deep median incision to form
deeply dissected to form eight elongate, subparallel- two long lanceolate segments with rounded apices;
sided or slightly expanding ultimate segments. Leaf veins forking in proximal third ofthe lamina andthen
mm
lamina40-100 longandwide, contractingbasally runningstraightandparalleltodistalmargin,venation
mm
at a convergence angle of 45°-120° to a tapering indistincttowell-definedat 8-12/10 across distal
mm mm
petiole 1-3 wide and to 25 long. Venation portion ofsegments.
forking inproximal portion ofthe laminato form 4-8
veins running parallel to apex ofultimate lobes at a Material
density of 15-20/10 mm. AMF126857, AMF125102, Coal Mine Quarry;
AMF
125101, Reserve Quarry.
Material
AMF129958, 129973-4, 121027-30, 121041-2, Discussion
121044, Coal Mine Quarry; AMF129970, 129975, The rare Nymboida specimens are similar in
Reserve Quarry. shape, size andvenationtothe once-divided leaves of
S. sectina from South Africa illustrated by Anderson
Discussion and Anderson 1989 P1.63 figs 1-7, P1.64 figs 3-
The abundant Nymboida leaves that are placed 6,11,12. Cuticle ofsome ofthe SouthAfricanmaterial
in this complex often form 'autumnal banks' on some has beenpreserved and described.
horizons at both Coal Mine and Reserve Quarries.
Theyarevariableinsizeandmaimerofdissectionand
are generallysmallerthanleaves of5". schenckiisensu Sphenobaiera nymbolinea Holmes andAnderson
stricta fi-om the Molteno of South Afiica (Anderson sp. nov.
and Anderson 1989, 2003). The enlarged specimen Figures 26A-C; 27A, 28A.
illustrated in Fig. 21E shows portions ofthree leaves
attached to a stem. The leafassemblage on Fig. 22D Diagnosis
displays leaves showing a wide range ofdissection. Large Sphenobaiera leaf, lamina narrowly
Sphenobaiera leaves which form the most diverging and biflircating proximally into c. 16 long
commonly occurring element in the Middle Triassic linear segments.
Benolong Flora ofcentral western New South Wales
were described by Holmes (1982) as a new species Description
mm
S. ugotheriensis That taxon was synonymised with Leafas preserved 145 long and probably to
.
mm mm
S. schenckii by Anderson and Anderson 1989. The 200 when complete, 50 wide, bifiircating
BenolongleavesaregenerallylongerthanS. schenckii four times in proximal third ofleafto form 16 linear
mm
and, in many cases, with much broader terminal segments each 1-1.5 wide; angle of divergence
segments (Holmes 1982, Fig. IOC). We consider that ofthe lamina from the stout sessile base c. 25°; veins
S. ugotheriensis should stand as a valid species. not visible but with possible midrib and longitudinal
striations.
Sphenobaiera sectinaAnderson andAnderson Holotype
1989 AMF125104,Australian Museum, Sydney.
Figures 24A; 25A,B
Type Locality
Holotype Coal Mine Quarry, Nymboida. Basin Creek
Sphenobaiera sectina Anderson and Anderson Formation, Nymboida Coal Measures, Middle
1989, Specimen BP/2/824 Triassic.
Selected reference Other material
1989 Sphenobaiera sectina Anderson and AMF125105, Coal Mine Quarry; AMF125106
AMF
Anderson p.143, pi.64. and counterpart 125107, Reserve Quarry.
Description Name derivation
mm
Medium-sizedSphenobaieraleaves, 90-120 Confrived from type locality and the linear
ultimate leafsegments.
Proc. Linn. Soc. N.S.W., 128, 2007 161
TRIASSIC FLORA FROM NYMBOIDA GINKGOPHYTA
-
A
Discussion Sphenobaiera sp.
The only material ofthis taxon collected to date Figures 25C,D
is two individual leaves and a slab and its counterpart
bearing stems and leaves. S. nymbolinea is similar Description
A mm
in form but twice the size of a specimen from the very small incomplete leaf c. 20 long,
mm
Ipswich Coal Measures referred to Czekanowskia 25 wide, base missing; angle of divergence c.
tenuifolia by Jones and deJersey (1947 Text fig.55) 90°; lamina divided almost to the base into eight
and also illustratedby Hill et al. (1965 pl.T9 fig.2). In straight-sided segments expanding distally. Veins are
form S. nymbolinea lies between the much smaller S. conspicuous, bifurcating occasionally to run straight
pontifolia Anderson and Anderson (1989) with eight andparallelto the segmentmargins; veindensitynear
segments and S. africana (Baldoni 1980) Anderson segment apices c. 45/10 mm.
and Anderson (1989) with 32 segments. The part
and counterpart surfaces of the slab illustrated in Material
Figures 26C, 27A and 28A show a mass of leaves AMF125103, Coal Mine Quarry.
probably attached to the lateral axis ofthe main stem.
Unfortunately the crucialpoints ofattachment arenot Discussion
clear on either surface. From its small size and very dense venation, this
leafdiffers fromallpreviouslydescribedginkgophyte
Sphenobaiera sp. cf. 5. brownianaAnderson and leaves.Howeverbetterpreservedmaterialisneededto
Anderson 1985 adequately describe this leafform as a new species.
Figures 29A, 30A,B
Fructifications associated witli Ginltgophyte
Description leaves
Large incomplete acutely wedge-shaped
mm
Sphenobaiera leaves; estimated length from 200 From their large collections of Late Triassic
to 350 mm; lamina deeply incised to form four or plants firom the Molteno Formation of South Africa,
mm
more long parallel-sided segments from 15-20 Anderson and Anderson (2003) have evidence with
wide; apices not preserved; veins bifurcating near varying degrees of certainty on the affiliation or
the base then running straight and parallel towards attachment of fertile organs with Ginkgophj^e-like
mm
the apex, coarse, 5-8/10 across distal width of leaves. The female strobilus Avatia and the male
segments. strobilus Eosteria are regarded as the fertile organs
of plants bearing Ginkgoites leaves. Neither Avatia
Material nor Eosteria organs have, so far, been collected
AMF125108, 125110, Coal Mine Quarry; at Nymboida. From the Molteno Formation both
AMF125109, Reserve Quarry. the female {Hamshawvia) and male (Stachyopitys)
reproductive structures have been found in organic
Discussion attachmentwithSphenobaiera leaves. Onthebasis of
By their large size and long strap-like segments their unique differences to other Gondwana Triassic
these uncommon Nymboida leaves are compared ovulate genera Anderson and Anderson (2003) have
with S. browniana, a species known only from three placed the Ginkgoites and Sphenobaiera genera in
incomplete leaf fragments fi-om the Burgersdorp separate families and orders. While specimens of
Formation of South Africa (Anderson and Anderson bothHamshawvia andStachyopitys are present in the
1983 p.l56, 157, pi. 184; 1989 p.l47). The South Nymboida collections, neither are found in organic
African leaves are significantly larger being more attachment but do occur in close association with
mm
than 400 long, with assymetrical dissection and Sphenobaiera leaves (Figs 10D,E, 31A-C). The slab
unclear venation. fromNymboidabearingtwoHamshawviareceptacles
The surface ofthe slab illustrated in Figure 29A was illustratedbut not described in Holmes (1996).
shows an assemblage of several incomplete leaves.
ThelargestleavesoftheNymboida 'S. stormbergensis Genus HamshawviaAnderson andAnderson
complex' (Figure 12B, 13A) have long parallel-sided 2003
mm
segmentsbuttheyare lessthan200 longandhave
denser venation than those of5. sp. cf S. browniana. Type species
Hamshawvia baccataAnderson and
Anderson 2003 p.214
162 Proc. Linn. Soc. N.S.W., 128, 2007
HOLMES AND ANDERSON
W.B.K. H.M.
number of ovules which are arranged in two rows
Hamshawvia distichos Holmes andAnderson sp. on either side of the midrib. Stiphorus, a genus of
nov. ovulate organs from the Late Permian of Eurasia
Figures 10D,E;31A-C (GomankovandMeyen 1980; Meyen 1987) is similar
in gross morphology to Hamshawvia but differs by
Reference the external attachment ofthe ovules. The strobili of
1996 'paired ovulate organ' Holmes PI.1.1 Hamshawvia distichos cannot be affiliated with any
specific leaftype as they are preserved on a bedding
Diagnosis plane of coarse grey shale in close association with
AlargeHamshawviastrobiluswithpairedbroad- three distinctmorpho-species ofSphenobaiera leaves
ovate fleshy megasporophylls bearing two rows of (Fig. 10).
embedded ovules on either side ofthe midrib.
Description Hamshawvia sp.A
mm
Peduncle stout 17 long, base missing, 2.5 Figures 32A,B
mm
wide, longitudinally striated, bifurcating into
mm mm
short tapering pedicels c. 5 and 8 long, each Description
bearingasingleterminalfleshybroad-ovatereceptacle A small Hamshawvia with an elongated slender
mm mm mm mm
c. 18 long, 15 wide, margins entire, apices peduncle 18 long (as preserved), 1 wide,
rounded; dorsal surface (Fig. 31A) showing a stout bifiircating to form two pedicels (one missing); the
median vein with c. six lateral veins on either side preserved pedicel arching and expanding into the
departing at an acute angle, arching and dividing into base of a reniform to semi-circular megasporophyll
mm mm
three proximally and two distally; ventral surface 6 long, 8 wide; margin entire; apexrounded;
(Fig. 31B,C) carbonaceous, revealing two rows of surface vermcose; no venation or ovules visible.
embedded ovules on either side ofmidrib, the outer
row with c. eight ovules, the irmer row with c. four; Material
mm
ovules rounded, c. 1 in diameter. AMF125111, Coal Mine Quarry, Nymboida.
Holotype Discussion
AMF AMF
129946 and counterpart 129950, This single small incomplete specimen is
Australian Museum, Sydney. obviously aHamshaviabut as the presence ofovules
in the receptacle cannot be determined it has not
Type Locality been formally named. It is preserved in fine white
Coal Mine Quarry, Nymboida. Basin Creek sandstonetogetherwithfragments offerns. The shape
Formation, Nymboida Coal Measures, Middle and surface texture ofH. sp. A is somewhat similar
Triassic. to H. longipedunculata from the Molteno Formation
(AndersonandAnderson2003 p.215,pi.70,figs 1,4,5)
Other material but lacks evidence of the embedded ovules that are
AMF AMF
130176 and counterpart 130177 on arrangedradially about the midvein in that species.
same slab as holotype and its counterpart.
Name derivation Genus Stachyopitys Schenck 1867
distichos (Greek) two rows, referring to the
two rows of ovules on either side of the receptacle Type species
midrib. Stachyopitys preslii Schenck from Bavaria,
Germany, Triassic.
Discussion
A
Only the holotype (Fig. 31 A,C) and one other specimen with a strobilis of Stachyopitys
strobilis, both on the same slab (Fig. lOA and lOE) lacrisporanga and a leaf of Sphenobaiera africana
and their counterparts have been collected. They are attached to a common bulbous base (Anderson
very similarandwerepossibly derivedfromthe same and Anderson 2003 pl.81(l-3)) from the Molteno
butunknownparentplant. Formation of South Afi-ica has confirmed the
Hamshawvia distichos differs fi-om all Molteno affiliationofStachyopitys asthemale fincttficationof
Hamshawvia spp by its larger size, andbythe greater the plantbearing Sphenobaiera leaves.
Proc. Linn. Soc. N.S.W., 128, 2007 163
:
TRIASSIC FLORAFROM NYMBOIDA GINKGOPHYTA
-
Stachyopitys sp. cf. S. matatilongus Anderson and CONCLUSION
Anderson 2003
Figures 33A-D, 34A, E We have endeavoured to illustrate the full range
of Nymboida Ginkgophyta to enable meaningfiill
Description comparisons with fiiture collections. Leaves
mm
The male strobilus (Fig. 33A) is c. 24 long, collected from the Basin Creek Formation of the
mm
base and apex missing, axis c. 1 wide, with Nymboida Coal Measures have been placed, on the
mm
spirally attached pedicels 2-2.5 long, branching basis of gross morphology, into the morpho-genera
and bearing terminal radial clusters of 5-8 elliptical Ginkgoites (with 4 spp.) and Sphenobaiera (with 8
mm mm
microsporangia each c. 1.5 long, 0.5 wide. spp). Where numerous specimens of a particular
form were available to show the range of variation
Material we have referred to that taxon as a 'morpho-species
AMF125112-5, Coal Mine Quarry. complex' eg. 'Ginkgoites denmarkensis complex'.
Seven of our species compare well with previously
Discussion described species from the Gondwana Triassic flora.
The rare specimens of5. sp. cf. S. matatilongus We have described one new species of Ginkgoites
from Nymboida are closely similar to the Molteno andthreenew species ofSphenobaiera. Comparisons
specimens of S. matatilongus by the elongated have mainly been made with the recently reviewed
strobili bearing clusters ofmicrosporangia borne on Ginkophyte floras from the El Tranquilo Flora of
branching pedicels, but differ by the straight elliptic Patagonia (Gnaedinger and Herbst 1999) and the
shapeofthemicrosporangia. Shirley(1898)described comprehensively collected and described Molteno
two species of Stachyopitys from the Ipswich Coal Formation of South Africa (Anderson and Anderson
Measures of Queensland as S. annularoides and S. 1989, 2003). The presence ofHamshawvia distichos
simmondsii. Anderson andAnderson (2003) regarded andH. sp. Aare the first descriptions ofGinkgophyte
S. annularoides of Shirley as a species ofPteruchus ovulate structures from Australia. Two species of
but agreed that the dispersed microsporangia Stachyopitys are compared with Molteno material.
described in Walkom (1917) as 5*. annularoides were
indeed Stachyopitys. The microsporangial clusters
ofWalkom are similar to the Nymboida S. sp. cf. S. ACKNOWLEDGMENTS
matatilongus. S. simmondsii differs from S. sp. cf S.
matatilongus by its much smaller size and from S. W.B.K.H. gratefully acknowledges the help of
sp. cf S. lacrisporangia (below) by the shape ofthe his family over many years in collecting material from
Nymboida. A grant from the Betty Mayne Scientific
microsporangia.
Research Fund provided financial assistance towards the
preparation of this paper. The Director and staff of the
National Herbarium, SANBI, Pretoria, South Afiica are
Stachyopitys sp. cf. S. lacrisporangia Anderson thanked for the use offacilities and providing the Molteno
andAnderson 2003
Fossil Plant Collection forexamination.
Figures 34B-D
Description REFERENCES
A
fragment ofa sfrobilus (Fig. 34B) bearing four
microsporophyllsandfivedetachedmicrosporophylls Anderson, J.M andAnderson, H.M. (1983). Palaeofloraof
(Fig.34 C,D), eacharadial clusterofc. 10tear-shaped southernAfrica. MoltenoFormation (Triassic) Vol.1
mm
microsporangia, c. 1 long. Part \,Introduction. Part2,Dicroidium. Balkema,
Rotterdam.
Anderson, J.M andAnderson, H.M. (1985). Palaeoflora
Material
ofsouthernAfrica. Prodomus ofSouthAfrican
AMF126855-6, Coal Mine Quarry. megafloras, Devonian toLower Cretaceous.
Discussion Balkema, Rotterdam.
This fragmentary Nymboida material has Anderson, J.M andAnderson, H.M. (1989). Palaeofloraof
microsporophylls with tear-shaped microsporangia southernAfrica. MoltenoFormation (Triassic). Vol.2:
Gymnosperms (excludingDicroidium). Balkema,
similar to, but larger than those ofS. lacrisporangia
Rotterdam.
from the Molteno Formation and the complete Anderson, J.M andAnderson, H.M. (2003). Heyday ofthe
strobilus is not known. gymnosperms: systematics andbiodiversity ofthe
Late Triassic Molteno fioictifications. Strelitzia 15,
1-398.
164 Proc. Linn. Soc. N.S.W., 128, 2007