Fossil fruit of the Grevillecae (Proteaceae) in the Tertiary of eastern Australia

2005·5 MB·English

by  M E Dettmann

\
FOSSIL FRUITOF THE GREVILLEEAE (PROTEACEAE) IN THE TERTIARY OF
EASTERN AUSTRALIA
MARY E. DETTMANN AND H. TREVOR CLIFFORD
Dettmann, M.E.&Clifford,H.T.2005 1231:FossilfruitoftheGrevilleeae(Proteaceae) in
the Tertiary ofeastern Australia. Memoirs ofthe Queensland Museum 51(2): 423-438.
Brisbane. ISSN 0079-8835.
ConchothecarotundataF.Muell., 1873afossilfruittaxondescribedfrommid-Tertiarydeep
lead sediments at Haddon, Victoria is morphologically and anatomically consistent with
fruits ofextant Grevillea (Tribe Grevilleeae). The fossil taxon, which is redefined on the
basis of the type and other specimens, accommodates uniloculate, tardily dehiscent,
ellipsoidal fruits with stalk attachment displaced laterally towards the style and a thick,
woodypericarpthat isradiallystructured. Thefossil fruitevidencetakentogetherwiththat
offossilleavesandpollenassociatedwithGrevilleademonstrateahistoryoftheTribetoat
least the latest Cretaceous (Maastrichtian) in the Australian vegetation. Conchocaryon
smithiiF.Muell., 1879,afossil fruitfromMiocenesedimentsatGulgong,NewSouthWales
may also have affinities with Tribe Grevilleeae, but the protocol specimen, which is
refigured herein, hasnotbeen locatedand isbelieved lost. Forcomparativepurposes, fruit
and seed structure are documented ofextant members ofTribe Grevilleeae (Grevillea,
Hakea Finschia) and ofBuckinghamia (sisterto Grevilleeae on molecularevidence).
,
Proteaceae, Grevillea, Conchotheca, Conchocaryon,fossilfruit, Australia, Tertiary
Mary> E. Dettmann and H. Trevor Clifford, Queensland Museum, PO Box 3300, South
Brisbane, 4101, Australia; 9June2005.
TheTribe Grevilleeaecomprisesthreegenera, Conchotheca rotundata F.Muell. to pericarps of
tHwaokeaofScwhhriacd.h&(GJr.eCv.ilWleenadl.Kn-i1g5h0ts-pp3.6)3arseptp.h,e tahgraeiensetxtaasnstigGnrienvgiltlheeafosspseiclisest.oGArletvhiolulgeah ahregulaitnegr
,
most species-rich of the Proteaceae in the (1882: 44) noted that they, like the pericarps of
Australian flora, plus Finschia Warb.with four Grevillea areattachedto stipes that are laterally
species centred in New Guinea and adjacent displaced,with respect to the style. The fossils
islands (Fig. 1).WhereasFinschiaaremostlytall wererecovered fromdeep leadsedimentsduring
trees ofrainforests, open woodlands and swamp gold mining activities in the 1850’s-1870’s near
forests in high rainfall areas,Hakea (endemic to Haddon, Victoria (Mueller, 1873, 1874a,b), and
Australia) has near pan-Australian distribution subsequently reported (Mueller, 1879; Barnard,
andisconcentratedinthedrierregions,occurring 1881) to have been recovered from beneath
as low trees and shrubs in open woodlands,
heathlands, and coastal communities. Grevillea Tertiarybasaltsat BeaconsfieldnearLaunceston
, (Tasmania), Clifton (Queensland) and Gulgong
wspipt.h),itesxtdeinstdrsibtuotiNonewceCnatlreeddoniina,AuNsterwaliGaui(n3e57a (New South Wales). Another fossil fruit taxon,
and Sulawesi, includes tall trees and shrubs of Conchocaryon smithii F.Muell. (1879: 39) most
closed toopen forests and woodlands (mostly in likelyfromtheGulgonglocalitywasdescribedas
high rainfall or monsoonal regions of northern resembling pericarps of Grevillea and Hakea.
andeastern areasofits range), and small treesto The enclosed seed, which was reported with a
spreading and prostrate shrubs especially under ‘terminal wing-like appendage’, intimated a
lower rainfall regimes in southern and Western closerresemblancetoHakeathan Grevillea.The
Australia. fossil taxon was discriminated from Hakea on
By contrast to the high diversity levels and account of possessing only one seed, and a
pericarpwitha ‘lesserdegree’ofdehiscence. No
almost pan-Australian distribution of Grevillea
and Hakea in the present-day vegetation, their further evaluation ofthe systematic affinities of
past history is virtuallyunknown from the fossil either Conchotheca rotundata or Conchocaryon
record. The possibleoccurrence ofthe genera in smithii has been undertaken and there is no
AustraliaduringtheTertiarywasfirsthintedatby reference to them in reviews ofthe macrofossil
Mueller (1873: 41). He noted the ‘general record of Australian Proteaceae (Carpenter,
appearance’ of fossil fruits attributed to 1994; Hill et al., 1995).
MEMOIRS OF THE QUEENSLAND MUSEUM
424
FaInGd1l.oMcaatpioonfsthfersoomutwhhwiecshtPfaoscsiiflicfrrueigtsi,onlseahvoews,inagnpdrepsoelnltendisthtartibcutoinofnorramnsgewiotfhGrTerviilbleeaG,reHvaiklelae,eaaendhaFviensbceheina
reported; also indicatedaredoubtful fossilrecordsoftheTribe.
To clarify the status and affinity of Mueller’s described and figured and the fossil record of
taxa, protocol specimens were sought Irom Grevilleeae is reviewed.
museums inVictoriaand New South Wales. The MATERIAL
single specimen on which Conchotheca
rotundata was based was located in the Museum Fossil fruits investigated include the protocol
ofVictoriatogetherwithseveralotherspecimens material and other specimens of Conchotheca
subsequently collected. No specimens of rotundata F.Mucll., 1873 housed in the
Conchocaryon smithii were found; the species collectionsoftheMuseumofVictoria(catalogue
numbersprefixedNMVP).Thefruitsarewoody,
was defined on the basis ofone specimen, but
some retaining well preserved anatomical
neither it nor subsequently reported specimens characters, and others are vitrinised and/or
were located. Comparisons have been
pyritisedwithfewanatomicalfeaturespreserved.
undertakenofavailablefossil materialwith fruits None retains original seed material, which
of the three Grevilleeae genera (Grevillea, appears to have been lost since investigated by
Hakea,Finschia),andofBuckinghamiaF.Muell. Mueller (1873), Specimens examined are from
(Tribe Embothrieae), which on molecular Smythe’sCreek(ReformCo. Shaft,-47.5m)and
evidence isthe sistergroup to Grevilleeae (Hoot Nintingbool (Crucible Co. Shaft ~ 23.2m), near
& SW
Douglas, 1998). Fruitsoftheextantgeneraare Haddon (37°18’S 146°32,E), of Ballarat,
.
FOSSIL FRUIT OF THE GREVILLEEA 425
Victoria. These were collected from deep lead hypochloritefor 1-2hours,followedbythorough
sediments that underlie Miocene basalts. An washing in distilled water and mounting in
Oligocene or Early-Middle Miocene age ofthe glycerine jelly on glass microscope slides.
sediments has been considered most likely Anatomicalcharactersofmatureseedcoatswere
(Rozefelds & Christophel, 1996; Dettmann & examined in transmitted light after clearing as
Clifford, 2001). Specimens were reported from designatedabove.
probable Oligocene sediments at Ophir Gold Toprovideabasis forthecomparisonoffossil
Mine, BeaconsfieId, Tasmania (Mueller, 1879), and living fruits, morphological and anatomical
Middle Miocene sediments in Black Lead, features of fruits of several modem species of
Gulgong, New South Wales(Barnard, 1881)and Grevillea, Hakea, Finschia and Buckinghamia
Clifton, Queensland (Mueller, 1879), but these are outlined in Appendix.
havenotbeenlocated.NomaterialofConchocaryon
SYSTEMATIC PALAEOBOTANY
smithii has been located; the single specimen
described and illustrated by Mueller (1879)
probably came from deep lead sediments of Conchotheca F.Muell., 1873, emend.
Middle Miocene age at Gulgong, New South 1873 ConchothecaF.Muell.,p.41
&
Wales (Dettmann Clifford, 2001).
TYPE SPECIES(by monotypy). Conchothecarotundata
Comparativematerialinvestigated(Appendix) F.Muell., 1873,emend.
includes fruits of several Grevillea and Hakea
EMENDED DIAGNOSIS.
speciesandofBuckinghamiacelsissimaF.Muell. Fruit laterally
cultivated or from the wild in southeastern compressed prolate ellipsoidal or spheroidal,
Queensland. Developmental stages of fruit withbilateralsymmetryonlyabouttheplanethat
maturation were traced for several of these includes stalk, style base, and ventral suture
species whose identities were verified by (potentialdehiscenceline); indehiscentortardily
reference to the collections of the Queensland dehiscent, splitting into 2 equal portions;
Herbarium. Additionally mature fruit of unilocular. Stalk base displaced dorsiventrally
GrevilleacandicansC.A.Gardnerwereobtained (laterallytowardsstyle),theventralsuturelonger
from Rings Park, Perth, Western Australia, and than dorsal hinge line. Surface smooth or
of Finschia chloroxantha Diels from the near-smooth. Fruit wall in transverse section
Singapore Herbarium. radially structured, the outer pericarp with
radially aligned fibres, the middle pericarp with
METHODS
radially aligned fibres associated with
Fossil and modem fruits were studied using a predominantly longitudinal vascular bundles,
and the inner pericarp predominantly of
binocular dissecting microscope. Several ofthe
woodyfruitsweresectionedinthetransverseand parenchyma. Seed laterally attached, solitary
longitudinal planes using a jeweller’s saw, and filling, or almost so, locule. Seed flat, roundish,
unwinged.
the resulting surfaces polished on fine emery
paper to reveal details of anatomy. Specimens REMARKS AND COMPARISON. When
photographed include the type specimen of proposed thegenuswasmonotypicandbasedon
Conchotheca rotundata illustrated by (Mueller, a single specimen (Mueller, 1873: 41, pi. 6, figs
1873, 1874b); this specimen is depicted in Figs 9-11), which is re-figured herein (Figs 2A-G,
2B-G, 4C,D together with reproductions of the 4C,D); the seed referred to by Mueller has not
original lithographic illustrations (Fig. 2A). been located. Additional specimens were
Additional anatomical detail was obtained for subsequently collected (Mueller, 1882: 44;
fruits of Grevillea heliosperma R.Br., Hakea 1883), but none was illustrated. Mueller (1882)
laurina R.Br., Finschia chloroxantha and noted further characters of the seed
,
Conchothecarotundatafromfragmentsmounted (flat-compressed, almost truncate at one
on stubs and gold plated for scanning electron extremity, slightly apiculate at the other; testa
microscopeanalysisusingaPhillipsinstrument. membraneous, minutely granular), but none of
Several developmental stages of fruits and the specimens we examined possesses seed
seedswere studied in GrevillearobustaA.Cunn. tissue. Nevertheless, the vascular trace from the
ex R.Br., G. hilliana Maiden, Hakea actites ovary wall to the placenta confirms lateral
W.R.Barker, and Buckinghamia celsissima. attachment of the seed. A second species, C.
Dissectedovariesandhandcutsectionsofyoung turgida referredtothegenusbyMueller 874a:
, (1
fruits were cleared in aweak solution ofsodium 42, 1874b: 24) was differentiated from C.
MEMOIRS OF THE QUEENSLAND MUSEUM
426
mm mm
1 1
1
FOSSIL FRUIT OF THE GREVILLEEA
427
rotundata in being smaller and with a dehiscence line or ventral suture; indehiscent or
tCh.intnuerrg-wiadlalecdopmeprirciasrpe. Itlwloustrmaotredphsopleocgiimcenaslloyf tianrsdeirltyeddehsiesecde.nt;Staunlikloacutltaarc,hmweitnht 1dilsaptlearacleldy
distinct forms, each of which differs from dorsiventrally; ventral suture twice length of
ConchothecaF.Muell.emend., inthattheirstyles dorsal hinge line. Stalk base circular, l-2mm in
and stalksarein vertical alignment, theirventral diameter; style base inconspicuous, represented
suturesanddorsalhinge linesareequal in length, byfaintscar. Fruitwithasmoothornear-smooth
and theirseedsareapicallyattached. Both forms surface. Pericarp up to 2-3mm thick at midpoint
are excluded from Conchotheca as emended oflateralsurfaces,taperingto 1.5-2mmatventral
herein, and will be transferred to a new genus suture and dorsal hinge line. In section pericarp
&
(Dettmann Clifford, in prep.). radiallystructured,theouterandmiddlepericarp
Conchocaryon F.Muell., 1879, a monotypic with radially aligned fibres directed outwards
genus based on a single specimen ofC. smithii from the predominantly vertically aligned
F.Muell. 1879,wasdescribedaspossessingseveral vasculature that demarcates the boundary
ofthecharacters displayed by Conchotheca, but betweenthe middleand innerpericarp, the latter
was segregated on account of its shape being of which is composed predominantly of
‘unsymmetrical’ratherthanellipsoidal.Afurther parenchyma. Seed flat, roundish, unwinged*
distinction noted between the two genera was
that the seed ofConchocaryon was described as DIMENSIONS. Fruit; length 11.5 (12.8) 14mm;
possessing ‘a Hat terminal appendage’(wing) in lateral axes, 10 (11.8) 13.5mm (in plane of
contrast to the unwinged seed of Conchotheca dehiscence) x 9 (10.6) 13mm (at right angles to
(Mueller, 1879: 39). The specimen on which dorsal-ventralplane).Seeddimensionsunknown.
Conchocaryonwrasbasedhasnotbeen located in REMARKS. One valve of the holotype has
pmruesseuummeds lionst.SyDdetnaeiyledorcoMmeplabroiusronnes,beatnwdeeins cpir.a6c,kefdigasn9d-1sp1l;itMsuienlcleeri,llu1s8t7r4abte,dp(lM.u6e,lfliegrs.91-1817)3.,
the twogenera were thus precluded. Thedorsiventraldisplacementofthestalk with
Conchotheca rotundata F.Muell. 1873, respecttothestyle in thefruitswasnotspecified
emend. in the original diagnosis, but w'as hinted at by
(Figs 2, 3A-D, 4C,D) tMhureelelers’pseccioemspaorfistoronpoicfatlheGfroesvsiillslewaith(Mfureulitlsero,f
M(2ATvaElRvIesALo.fHfoOllLicOleT;YvePrEtic(ablyamxoinsot1y4pmym);:NlMatVePra5l3a9xe7s, t1h8e73a:s4y1m)m.eHtreyemopfhaCsoinscehdot(hMeueclalerro,tu1n8d8a2:ta44i)n
12.5mm(in planeofdehiscence) x 10mm; pericarp wall lateralviews,notingthatit‘seemstohaveitsfruit
2-3mm thick). Figs 2A-Q 4C,D. OTHER MATERIAL. laterallyaffixedtoastipes(sic)’.Thus,thedorsal
NMVP53972. NMVP53553, NMVP206494 (Coll. R.A. Lock. hingelineisconsiderablyshorterthantheventral
Nintingbool, but identified by F.Muelleras Conchotheca suture(Figs2A,B,C,H,4C),afeatureoffruitsof
turgida). extant Grevillea and here illustrated for G.
,
candicans (Fig. 5H), G. heliosperma (Figs 4A,
TYPE LOCALITY. Deep leads at Haddon, Nintingbool 5A,B), and G robusta (Fig. 5L,M).
(Crucible Co. Shaft, -23.2m), Victoria; ?Early-Middle
Miocene. Mueller’s characterisation of the seed is
acceptedhereineventhoughnoseedmaterialhas
DESCRIPTION. Fruit prolate ellipsoidal to been observed in the holotype and other
subspheroidal, bilaterally symmetricalabout the specimens studied; it appears that the seed
plane that includes stalk, stigma, and potential material described by Mueller has been lost or
FIG.2 (facing). Conchotheca rotundata F.Muell. A-G, Holotype, NMVP53971, H-K, from Nintingbool
(Crucible Co. Shaft, -23.2 m), Victoria. A, Lateral views showing interior of locule, and external views
showingdorso-ventralsuturebeforeseparationintotwovalvesandlateralsurfacerespectivelyasillustratedby
Mueller(1873,pi.6,figs9-11),arrowsindicatepositionofstalk(s)andstigma(st);B,C,interiorview'soflocule,
arrows point to stalk (s) and stigma (st); D,E, external views of lateral surfaces; F,G, section ofvalve cut
transversetoventralsutureanddorsalhingelineshowinginnerpericarpwithisodiametriccells(p),andmiddle
and outer pericarp with vasculature (v) and radially aligned fibres (f); H,I, NMVP206494, lateral view of
interior ofvalve showing locule with infilling ofsulphurand detail ofpericarp wall in longitudinal section
respectively;J,K, NMVP53972, basalandapical viewsshowingscarsofstalk(s)and stigma(st).
428 MEMOIRS OF THE QUEENSLAND MUSEUM
FAIin,GmP3io.rdtdAil-oeDn,aonfCdopenorcuihtceoartrphpeeircniatcrararonpts-uvneCdr-asDte,a(,lFNairMbgrVeePsfa2ci0ne)6oa4bnl9di4qluofenrgaoinmtduNdmtirgnaatnlisn(vfbeaorcsoeelos(neCclrteufictoi)nbslesecutrCirooo.nu;SnBhd,aifnrtga,di-vaa2ls3lc.yu2laamlt)iug,rnVeeidcmtfoirmbiriaed.s
regionofpericarp. E-GConchocatyonsmithii,holotypc. E,F,Oblique,basalandlateralviewsasillustratedby
Mueller(1879, pi. 17, figs4,5); G,detailofpericarp fibres as illustratedby Mueller(1879,pi. 17, fig. 6).
FOSSIL FRUITOF THE GREVILLEEA 429
destroyed. Mueller(1873:41)statedthatthefruit 2F,G,I, 3A-D), and moreover, as in Grevillea
possessed one ‘flat, roundish’ seed, and later fruits, the wall is thickest midway between the
remarked (Mueller, 1882: 44) that ‘the ventralsutureanddorsalhingeline(Figs2F,4D).
well-developed seed completely fills the cavity, However,fruitsofallextanttaxaotherthanthose
is flat-compressed, almost truncate at one ofG. candicans(Fig. 5H,I)arereadilydehiscent,
extremityandslightlyapiculateattheother’. He although is some species like G. heliosperma,
further noted (1882: 44) that ‘the testa is (Figs 4A,B, 5A-C) and G. refracta the suture
membranous, minutely rough from granular may be barely evident until the late,st stages of
elevations, which are mostly arranged in short ripening.
lines, giving to the outside ofthe seeds a pretty
appearance’. Most Grevillea fruits have two laterally
attachedseeds,butthenumbermaybereducedto
DISTRIBUTION. (Fig. 1): Haddon (Smythe’s Creek, onebyabortion. In somespeciestheseedshavea
Reform Co. Shaft, ~47.5m; Ningtingbool, Crucible Co. broad peripheral wing (Fig. 5G,N), but in the
Shaft - 23.2m), Victoria (Mueller, 1873, 1874a); Ophir majorityofspecies,theseedsareunwinged(Fig.
Gold Mine, Beaconsficld, Tasmania (Mueller, 1879b); 5K). Although the unwinged seeds lack a broad
BlackLead,Gulgong,NewSouthWales(Barnard,1881). peripheral papery wing, they have a
AGE RANGE. ?OHgocene-Miocene circumferential structure such as a ‘rib’ or ‘ruff’
thatmaybea wing-homologue. One-seededness
AFFINITY. Mueller (1873: 41) considered C. is far more common amongst species with
rotundata distinct from Grevillea in lacking a unwinged seeds than in species with winged
‘conspicuous stipe’ (gynophore), but seeds. C. rotundata was described (Mueller,
subsequently acknowledged that ‘Conchotheca 1873) as having one, unwinged seed, but seed
rotundata seemstohave its fruit laterallyaffixed materialisabsentfromspecimensexamined,and
to a stipe, as in the case with many Grevilleas’ thus unambiguous verification of a Grevillea
(Mueller, 1882: 44; 1883: 21). In the absence of affinity for C. rotundata isprecluded.
flowers and leaves he cautioned against placing
the species in Grevillea. Tardily dehiscent, usually one-seeded fruits
We confirm that the C. rotundata fruit is Fthiantscahrieab(oSrlneeumeorn, l1a9t5er5a)lasntdipHesakaelaso(Boacrckuerrient
morphologically consistent with those of
al., 1999). Finschia is distinct in possessing a
Grevillea and shares with them the following
, corky pericarp comprising an exocarp ofcorky
characters: asymmetrical except about the plane
cells and a thick mesocarp of large stone cell
ofpotential dehiscence; dorsal hinge lineshorter complexes interspersed with corky tissue
than ventral suture; lateral attachment ofseeds;
external to the vasculature ofthemesocarp (Fig.
andradiallyalignedfibresinthemiddleandouter
6I,J). Hakea fruits are dehiscent, but at maturity
pericarp. C. rotundata is tardily dehiscent in the two portions remain united at the base and
contrast to Grevillea fruits, which have readily attached to the plant stem. In many species the
cdaenhdiisccaennst wfholilcihclaerse ienxdceehpistcefnotr. fruits of G. fruit has pronounced humps on the lateral faces
, resulting from secondary thickening of the
In terms of size and shape Mueller (1873) pericarp (Filla, 1926; Johnson & Briggs, 1963;
noted resemblance of C. rotundata to fruits of Barker et al., 1999). The pericarp, whether
several taxa ofGrevillea referred to the Hilliana significantly secondarily thickened or not,
and Heliosperma Groups (sensu Makinson, comprises stone cell complexes instead of
2000),andespeciallyGrevillearefractaR.Br., G. radially arranged fibres adjacent to the ventral
mimosoidesR.Br.,andG.polystachyaR.Br.(=G. suture and external to the vasculature in the
parallelaKnight).Theseandotherspeciesofthe mesocarp (Fig. 6B), In these respects Hakea
Hilliana and Heliosperma Groups of Grevillea fruitsdiffer from Conchotheca.
have fruits in which the stalk attachment is
dorsiventralwithrespecttothestylebase,andthe Fruits ofBuckinghamia differ from those of
thick pericarp wall is composed predominantly Grevillea and Conchotheca in that the dorsal
ofradiallyaligned fibres in the middleandouter hinge line is longer than the ventral suture (Fig.
zones external to the vascular bundles (Fig. 5Q,R). Moreover, in Buckinghamia the radially
5D-F)asdescribedandillustratedbyFilla(1926, directedvascularbundlesofthemiddleandouter
figs36-38,70d). Intheserespectsthefruitwallof pericarp are themselves branched (Filla, 1926,
Conchotheca rotundata is comparable (Figs fig.70f) as opposed to the unbranched radial
MEMOIRS OF THE QUEENSLAND MUSEUM
430
St
FIG 4 DiagrammaticoutlineoflongitudinalandtransversesectionsoffruitofGrevilleaheliosperma(A,B)and
holotypc NMVP53971. ofConchotheca rotundata(C,D); dh, dorsal hinge; 1, locule; ip, innerpericarp; mp,
middlepericarp; op. outerpericarp; pi, placenta; s, stalk; st, stigma; vb, vascularbundle; vs, ventral suture.
Note, fibres illustrated in upperrightsegmentonly.
FIG5(facing) FruitsandseedsofGivvillea(A-Q)andBuckinghamia(R-T).A-GGrevilleaheliosperma R.Br.
A B lateral viewsshowingexterioroffruit(d.dorsalhinge,v,ventralsuture)andinteriorofloculecontaining
winged seed arrows indicatepositionofstalk(s)and stigma(st); C, sectionoffruitcuttransverseto ventral
sutureanddorsal hingelineshowingtwowingedseedscuttransversely; D-F,portionofpericarpintransverse
sectionshowingradiallyalignedfibresinmiddleandouterpericarp(D)andvasculaturesurroundedbyfibresin
midregionsofpericarp(E,F);Gwingedseedshowingraphetrace(t)andseedbody. H-K.Grevilleacandicans
C AGardner H-I longitudinal and transversesectionsoffruitshowinginterioroflocule(s. stalk, st,stigma)
and unwinged seeds cut transversely (note only one seed with embryo); J. transverse section offruit wall
showing radial structure of middle and outer regions of pericarp, parenchymatous inner pericarp, and
underlying section ofseed coat (darker layer); K, seed, lateral view. L. Grevillea robusta A.Cunn. ex R.Br.
lateralviewoffruit(d dorsalhingeline,v,ventralsuture).M.N.P.Q,GrevilleahillianaF.Mucll.M.lateralview
ofinterioroffruit(d dorsalhinge,v.ventralsuture);N.wingedseedshowingbranchedrapheLrace(t);P.cellsof
locule lining Q inner epidermis oftesta with cells containing crystals ofcalcium oxalate. O, Grevillea
pteridifoliaKnight hemitropousovuleshowingovuletrace(t)passingthroughouterintegumenttochalazaand
hypostase. R-T,Buckinghamiacelsissima F.Muell. R,S,exteriorand interioroffruitin lateral view(d, dorsal
hinge,v,ventral suture); T,wingedseedshowingraphetrace(t)atmargin ofwing.
FOSSIL FRUIT OF THE GREVILLEEA 431
MEMOIRS OF THE QUEENSLAND MUSEUM
432
vasculature of Grevillea (Filla, 1926, fig. 70d; with base broader than apex; edge at ventral
Fig. 5E,F) and Conchotheca (Figs 2G, 3A). suture acute and obtuse at dorsal hinge line;
verticalaxis20mm, lateral axes 10-12mm. Stalk
Conchocaryon F.Muell., 1879 scar inset at base; fruit wall - 2mm thick,
composed of thick-walled (15pm thick) fibres
TYPE SPECIES (by monotypy). Conchocaryon smithii and/orsclereids up to 75pm in diameter; surface
F.Muell., 1879.
slightly rough. Seed attached laterally, the seed
DIAGNOSIS (Mueller, 1879: 39). ‘Fruit hard, body filling basal portion of cavity and with a
oblique-ovate, considerably compressed, short wing directed towards apex offruit.
one-celled, almostsmooth, dehiscent onlyalong
the anterior (ventral) margin, produced at the REMARKS. Characterisation of the species is
lower portion ofthe back into two acute ridges. based entirely on Mueller’s description and
Placenta narrow, dorsal in thecavity; itspoint of illustrations, and is provided should specimens
attachment to the seed about midway up at the conforming to the holotype be located. Mueller
dorsal innerangle ofthe pericarp. Seed solitary, (1879) introduced uncertainty as to the location
ovate, turgid, filling the lowerpart ofthe cavity, ofthedescribedspecimen;Gulgong isspecified,
extendedatthesummitintoaflatshorttriangular andthen qualified as possibly Victoria.
appendage’. AFFINITY. With the Proteaceae (Tribe
REMARKS AND COMPARISON. The genus Grevilleeae)assuggestedbyMueller(1879: 39),
was proposed on the basis ofone specimen and notwithstanding his suggestion the placenta is
was distinguished from Conchotheca on its ‘dorsal in the cavity’. Mueller compared the
‘unsymmetrical form’, the fruit bulbous in basal fossilwithHakeaonthebasisofthewingedseed
regions and tapering towards the apex (Mueller, and woody fruit wall, which is swollen towards
1879: 39). Further systematic evaluation ofthe the base, but as noted by him, living species of
taxon is precluded as neither the type specimen Hakeapossesstwoseeds,notone,asobservedin
noranvsubsequentlycollectedmaterialhasbeen the fossil.
located. Illustrations of the type, C. smithii,
DISCUSSION
(Mueller, 1879, pi. 17, figs4-6; 1883, pi.17, figs
4-6; Fig. 3E-G herein) implybilateral symmetry
andafruitwallthickestonbasalareasofthevalve AssuggestedbyMueller(1873), Conchotheca
rotundata is morphologically and anatomically
faces. consonant with fruits of the Proteaceae
Conchocaryon smithii F.Muell. 1879 (Subfamily Grevilleoideae), and is more similar
(Fig. 3F-G) to those of Grevillea, Tribe Grevilleeae than to
other members ofthe family. Less certain is the
HOLOTYPE (by monotypy). Mueller, 1879: 39; pi. 17, detailed morphology and affinities of
figs4-6. Conchocaryon smithii. Mueller (1879) believed
thesolespecimenresembled fruits ofHakeaand
TaYViPcEtorLiOaCnAloLcIalTiYty.'(GMuuleglolnerg,,1N8e79w:S3o9u);thMiWadldelse,Moiro‘cfernoem tToriabeleGsrseervielxlteeenateGirsevcialulteiao,usalnydaacnceapftfienditoynwitthhe
(Gulgong)oruncertain(Victorianlocality). basis of the original descriptions and
DESCRIPTION (after Mueller, 1879: 39). Fruit illustrations. Thus, irrespective ofuncertainties
asymmetrical about lateral axes, bilaterally surrounding affinities ofConchocaryon smithii
,
symmetrical about vertical plane that includes theTribehasahistoryinAustraliathatextendsto
stalk,stigmaandpotential dehiscence line;ovate at least the mid-Tertiary.
FIHG..a6ct(iftaecsiWng.R)..FBrauirtksera:ndB,selaetdesraolfvHiaekwesah(oAw-iFn)gainndteFriionrsochfilaoc(uGl-eL)s.hoAw,inHgakaebraupltaudreimnaarRc.aBtri.olnatbeertalweveienw“;daB-rFk,”
and“light”orsecondarywoodadjacenttodorsalhingeline(d)andstonecellsatventralsuture(v);C,transverse
section showing seed cavity (bottom centre), and sharp demarcation (arrow) between primary (inner darker
zone)andoverlyingpalersecondarywoodofpericarp. D-E,detailotsecondarywoodshowinglibritormfibres
(arrow)andoverlyingcorktissue;F,seedshowingbasalwingandraphetrace(t).G-L,Finschiachloroxantha
Diels; G,H, lateral views showing exterior and interior offruit, stigma (st), stalk (s); 1,J, longitudinal and
transversesectionsoffruitwallshowingstonecellcomplexes(see), vasculature(v),parenchyma(p)andcork
tissue(c); K,L,detailofvasculature(v)andparenchyma(p).