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Leporillus (Rodentia: Muridae) from Madura Cave, W.A. 'Ernest L. Lundelius, Jr. and 2William D. Turnbull 'DepartmentofGeological Sciences, University ofTexas, Vertebrate Paleontology Laboratory, Texas Memorial Museum, University ofTexas, Austin Texas 78712, USA; department ofGeology FieldMuseum ofNatural History, Chicago Illinois, USA Lundelius, E.L. Jr. andTurnbull, W.D. (1999). Leporillus (Rodentia: Muridae) from Madura Cave,W.A.ProceedingsoftheLinneanSocietyofNewSouth Wales121, 129-146. TwospeciesofthegenusLeporillusarerepresentedinthePleistocene-Holocenesedi- ments ofMadura Cave. Leporillus conditor is abundant and ranges from the surface to the deepest level (38,000 BP). L. apicalis is less abundant and appears to be restricted to levels datingfrom7,500to22,400BP. Mostofthe specimens are dissociated because they are derivedfromowl pellets and thusspecificidentificationisdifficult.Manyofthedimensionsoftheteethofthetwospecies overlapandtherearefewdiagnosticfeaturesthatseparatethem.WattsandAslingavecriteria forthe genus based on modern material. We have attempted to evaluate features that would separatethespeciesonthebasisofincompletecranialanddentalmaterials. Wedescribeafewofthebetterspecimens,discusstheirmorphologicfeaturesandhis- toricdistributions. Fromthisworkweareabletodocumentthetimespanoftheirpresenceon theRoePlain,thatpartoftheNullarborPlainsouthoftheHamptonScarp.Thespeciesdonot showanysignificantevolutionarychangesduringtheseintervals. Manuscriptreceived28July 1999,acceptedforpublication 15December 1999. KEYWORDS: Australia, dentition, Holocene, Leporillus apicalis, Leporillus conditor, Muridae,NullarborPlain,Pleistocene,Rodentia. INTRODUCTION This report is abstracted from an ongoing study ofthe rodents from Madura Cave, Part VIII of THE MAMMALIAN FAUNA OF MADURA CAVE. Here we report the presence of both species of the murid rodent genus Leporillus; L. conditor, the greater sticknest rat, or Walpilkara, and L. apicalis, the lesser sticknest rat, orTchujalpi, Turulpa, Tweealpi and show theirchronologic distributions withinthe cave deposits. There are well over 1,700 specimens of L. conditor ranging from the surface, all units between Unit 1, dated at 7,500 BP, to the bottom unit ofthe deepest trench, Unit 7, dated at 38,000 BP. L. apicalis is much less abundant; 59 specimens were recovered, none from the surface, most(38) fromUnit 1 and21 fromthe upperpartofUnit2. (15,600to22,400BP). Madura Cave is located on the Roe Plain, the area on the southern edge of the Nullarbor Plain, six miles south ofMadura, 110 miles west ofEucla. A fullerdescription of the cave is given in Lundelius and Turnbull (1973). The earlier illustrations of the cave map and trench sections are repeated here (Figs. 1^1) to give the reader convenient access to the stratigraphy encountered in each trench. AGE OFDEPOSITS Five radiocarbon dates from Trench 4 span a 30,000 year period between 7,470 ± 129 BP (TX 1146) and 37,880 ± 3,500 BP (TX 1143). Two radiocarbon dates from Trench 3 are 15,600 ± 250 BP (TX 1145) from the top ofthe second unit (red clay) and Proc.Linn.Soc.n.s.w., 121. 1999 130 LEPORILLUS(RODENTIA:MURIDAE)FROMMADURACAVE,WA .REAR TRENCH(#S) 010V—APPROX.POSITION TRENCH #2fELL-1956) ROCK HOLE=a REFERENCE POINTS— . MAGNETIC Figure 1.MapofMaduraCaveshowingthecentraldoline,thenorthernandsoutherntunnels,andthepositions oftheexcavations. (T« VI4B) 18.600t250V«P limi r CXCAVATION 4. WHITE SANOV SU.T RED CLAY •j Section C-C, Entrance Trench, 3. Figure2. Stratigraphicsectionexposed inTrench#3. Proc.Linn. Soc.n.s.w., 121. 1999 E.L.LUNDELIUSANDW.D.TURNBULL 131 ROCK HOLE „l_LI~ j. : l_T_LT_LT.i_,JLT-l.-I-l-,.-I--r pIpZI LIMESTONE ^XpI_ _ .X.pi.—J—j ,,,; ,-^r--- ( t . [-LT-r^-aT. ^ ^-T-l- -1. I „;„,,,.x,. --j-LL:..t,Yr}i^p±r±, l~r"iT'tT" DARK REDCLAV SILT {T*11**) 22,200 + S70 YHS» |.-4$&'..'•''•] SHAV-BPOWN SiLT RED-OKAY SAND AND HRAVCL Y'l:l.'^l.-M SCO CL*v. GRAVEL AT 'OP j 7I3HT SILT AND CLAV SEAMS VtUOW-OMANGE GRITTV HAND I HEO-ORAVOE SILTY CLAV ! (t»'1*3) 37,Hf)Ol 3.SJO VEIP Section A-A', Middle Trench, 4. Figure3.StratigraphicsectionexposedinTrench#4. B B' TRENCH GOES ON FOR CA-20' fflBgggBEBi brownsilt AND WHITE StLTV CLA REDDISH-BROWN SILT ORANGE-REO SAND AND GRAVEL REDDISH ORANGE CLAV AND GILT HED0I3H-BROWN 3ILT Figure4.CrosssectionofnortherntunnelatTrench#5showingthestratigraphicsectionexposedinthistrench. Proc.Linn.Soc.n.s.w., 121. 1999 132 LEPORILLUS(RODENTIA: MURIDAE)FROMMADURACAVE,WA 22,400 ± 580 BP (TX 1142) from the bottom of that unit. Correlations with the upper two units in Trenches 3 and 4 and Trench 1 (Lundelius 1963) can be made with reason- able confidence, but no firm correlations canbe madeforthe lowerunits ofthe trenches. MATERIALS AND METHODS Measurements, abbreviations and statistical and dental terminology are either those in standard use orthey aredefined where used. Specimen numbers beginning with PM are in the Field Museum of Natural History collection. Specimen numbers beginning with TMM are in the collection of the Texas Memorial Museum, University of Texas. The TMM designation is omitted from the number in the material lists. Measurements of the dentition were taken with a microscope reticle and with micrometer calipers calibrated to .01 mm. Cusp identifications and homology designations of murid upper molars have not been satisfactorily resolved. Hence it seems best to utilize a simple cusp designation scheme that makes no pretense at implying cusp homologies. Therefore we avoid using the Cope-Osborn scheme, or Vandebroek 1966, Hershkovitz 1971, Engesser 1972 or Jacobs 1977 and instead utilize that of Miller (1912, p. 801) as modified by Misonne (1969, p. 36) and here, so as to eliminate the remaining Cope-Osborn implied homologies. In Miller's scheme the upper molarcusps are designated by tl through t9 notations. This gives an unambiguous designation to each major cusp without any implied homology. Further, we follow Michaux's (1971) and Jacobs' (1977) use of the term "chevron" foreach transverse row ofcusps (Fig. 5A, left side). Most workers have used the Cope-Osborn terminology for the lower molars. We do not consider the implied homologies to be certainties but use the terms rather than introduce new terms which would only add confusion (Fig. 5B and C, center and right). The cusps labeled Prd, Hyd, End and Hyldprobably are the Cope-Osborn homologues of protoconid, hypoconid, entoconid and hypoconulid respectively. The homologies of those labeled Pad (paraconid) and Med (metaconid) however are dubious. For example, Misonne used Pad, which he states is more distal than the Prd. However that is the more usual position ofthe Med. Engesser (1972) uses Med for a cusp that is more mesial than the Prd., i.e. is in the usual Pad position. Our use ofthese terms is simply as cusp identi- fiers without any implied homologies. For the variable additional elements we use the designations Misonne employed (following Van de Broek 1966): sm, si, and sv. The homology ofthe cusps ofthe upperteeth ofmurids with those ofotherrodents is uncertain. The terminology used here is that ofMiller (1912) as modified by Michaux (1971). ORDER RODENTIA BOWDICH, 1821:7, 51 FAMILY MURIDAE ILLIGER, 1811:84 SUBFAMILY MURINAE ILLIGER, 1811:84 LEPORILLUSTHOMAS 1906:83 Watts and Aslin (1981) gave features ofthe skull that distinguish Leporillus from other genera of Australian rodents. In addition to size Table 1 summarizes the outstand- ing cranial and dental differences between L. conditorandL. apicalis. Leporillus conditor(Sturt 1848) Most of the hundreds of specimens are fragmentary, and are most likely derived from owl pellets. Proc.Linn.Soc. n.s.w., 121. 1999 E.L.LUNDELIUSANDW.D.TURNBULL 133 B med end med end med end Figure 5. Diagrams ofmuriddentitions (modifiedfrom Misonne 1969), showingcuspterminology (modified from Misonne 1969). Upperteeth are shown in A on left, lower teeth in B and C, center and right. Numbers 1-9 indicatethecusps(ortuberclesofsome authors)oftheuppermolars, a-lab=anterolabialcuspid, a-ling= anterolingualcuspid,end=entoconid, hyd=hypoconid, med=metaconid,pcd=postcingulid, andprd=protoconid. Forthe lowerteeth we show different age/wear stages. In B, the youngerofthe two, apost-cingulid cuspidispresent(pcdofml,m2),andinCthosecuspidshavewornawaysothattheir basesarefusedwiththe posteriorlophids.Forlowerteeth,MisonnefollowedVandebroek(1966)addingtheCope-Osborneequivalents, afewofwhichwequestion(seetext). Table 1. Size,cranialanddentalfeaturesthatdifferentiatethespeciesofLeporillus. Feature Leporillusapicalis Leporillusconditor Bodysize small large Lowermolars,median shallow deep longitudinalgroove m1,anteriorlophid nearlyevenlyrounded decidedlyV-shaped,openingforwards, sometimeswithacentralcuspid m2,posterior(3rd)lophid locatedinacentralposition central,butmoretiedtolingualendof (chevron) 2ndlophid m3,posteriorcuspid narrowbase;doesnotreach basebroad;swingstolingualsideof tolabialside tooth PosteriorlophofMl andM2 length&widthapprox.equal widerthanlong Anteriorpalatalforamen endsatfrontofMl usuallyextendstowidestpartofanterior lophofMl PositionofmentalforamenJustatfrontofmasseterictuberclewellanteriortomasseterictubercle Proc.Linn.Soc.n.s.w., 121. 1999 134 LEPORILLUS(RODENTIA:MURIDAE)FROMMADURACAVE,WA Material Surface 2 specimens, a skull in 3 pieces (TMM 41106-28, Fig. 6 A-D); and a left maxilla withMl-3 Trench 1. Unit 1. top 1 foot Skull 4partial skulls includingPM 6195 (Fig. 7) Upperdentition 35 left and 35 right specimens withteeth 5 left and 6 rightedentulous maxillae Lowerdentition 8 leftand 15 rightrami with i - m3, including PM 6181 (Fig. 6E-G) 32 leftand 22 rightrami with teeth, 1 edentulous rightramus Trench 1. top 30 inches Lowerdentition 1 leftramus with i, 1 edentulous leftramus Trench 1. 30 inches below surface Upperdentition 3 partial right maxillae with teeth Lowerdentition 5 leftand4 rightpartial rami withteeth Trench 2. Unit L Level 1 Upperdentition 1 right maxillawith Ml-3 Lowerdentition 1 left and 2 rightpartial rami with teeth Trench 2, 2 1/2 feetbelow surface Upperdentition 3 rightmaxillae withteeth, 1 edentulous rightmaxilla Lowerdentition 2 leftand 5 rightrami with teeth, 1 edentulous right ramus Trench 3. Unit unknown Upperdentition 1 left maxillawith Ml Trench 3, Unit2. Level unknown Skull 1 with left andrightMl-3, 1 with rightM2-3 Upperdentition 94 left and 108 right specimens with teeth, 6 isolated molars Lowerdentition 134 left and 129 right rami with teeth 16 left and 16 right edentulous rami Trench 3, Unit 2, Level 2 Upper dentition 33 left and 33 right maxillae with teeth, 1 right I 15 left and 12 rightedentulous maxillae Lowerdentition 6 left and 19 right rami with teeth, 2 left and 7 right edentulous rami Proc.Linn.Soc.n.s.w., 121. 1999 E.L.LUNDELIUSANDW.D.TURNBULL 135 Trench 3, Unit3 Upperdentition 14 leftand22rightmaxillae with teeth, 35 edentulous maxillae Lowerdentition 13 left and 10rightrami withteeth, 6 edentulous rami Trench4 Unit 1. Level 1 (top 1 foot) Skull 1 edentulous, lackingbackofbraincase Upperdentition 10leftand9 rightmaxillae withteeth, 5 edentulous maxillary fragments Lowerdentition 21 leftand 15 rightrami withteeth 14leftand9 rightedentulous rami Trench4, Unit2, Level 1 Upperdentition 24leftand 38 rightmaxillae withteeth 6leftand 3 rightedentulous maxillae Lowerdentition 53 leftand63 rightrami withteeth 4leftand 8 rightedentulousrami Trench4, Unit2, Level 1 (Middle Pit, top 6 inches ofred) Upperdentition 4leftand2rightmaxillae withteeth, and2 edentulous leftmaxillae Lowerdentition 8 leftand 8rightramiwithteeth, 3 edentulous rami Trench4. Unit2. Level 2 Upperdentition 22 leftand25 rightmaxillae withteeth 10leftand 14rightedentulous maxillae Lowerdentition 79 leftand56rightrami withteeth 12 leftand 13 rightedentulous rami Trench4. Unit2. Level 3 Upperdentition 1 leftand 1 rightmaxillae withteeth, 2 edentulous maxillary fragments Lowerdentition 1 leftand 8 rightrami withteeth, 2 leftand4rightedentulous rami Trench4Unit4-5 Upperdentition 9 leftand 16rightmaxillae withteeth, 24edentulous maxillaryfragments Lowerdentition 6 leftand 11 rightrami with teeth 12leftand 11 rightedentulousrami Trench4, Unit7. Level 1 Upperdentition 2 leftand 3 right maxillae with teeth, 1 edentulous maxillary fragment Lowerdentition 2 leftand 1 rightrami withteeth Proc.Linn.Soc.n.s.w., 121. 1999 136 LEPORILLUS(RODENTIA: MURIDAE)FROMMADURACAVE,WA Figure6. Leporillus conditor. A-D,TMM 41106-28, a nearlycomplete skull shown in A, anterior; B, leftlateral; C, dorsal; and D, ventral stereo views; E-G, PM 6181, left mandibular ramus with I, ml-3 shown in E, leftlateral; F.occlusal;andG, lingual views. Scalebarsare2cm. long. FMNH negativenumbersareG 85962- 85967. Proc. Linn. Soc. n.s.v... 121. 1999 E.L.LUNDELIUSANDW.D.TURNBULL 137 Figure 7. Leporillusconditor. A-D,PM6195, anearlycompleteskull shown in A,anterior; B,dorsal;C, left lateral;andD,ventralstereoviews. Scalebarsare2cm.long.FMNHnegativenumbersareG85954-85958. Proc.Linn.Soc.n.s.w., 121. 1999 138 LEPORILLUS(RODENTIA:MURIDAE)FROMMADURACAVE,WA Trench4. Unit7. Level 2 Upperdentition 5 leftand 14rightmaxillae with teeth, 6edentulous maxillary fragments Lowerdentition 11 left and 8 rightrami with teeth, 9 left and 8 rightedentulous rami Trench4. Unit7 Upperdentition 2 leftand 3 rightmaxillae withteeth, 6 edentulous rightmaxillae Lowerdentition 6 leftand 3 rightrami withteeth, 9 left and4rightedentulous rami Trench 5, LowerRedUnit Upperdentition 5 leftand5 rightmaxillae withteeth 15 leftand 21 rightedentulous maxillae Lowerdentition 2leftand 3 rightrami withteeth, 9 leftand 10rightedentulous rami Trench 5, LaminatedUnit Upperdentition 1 rightmaxillawithMl-3, 1 edentulous leftmaxilla 1 rightMl, and 1 leftM2 Descriptions Skull The skulls have the normal murid form. They have the myomorphous enlargement ofthe infraorbital foramina for the transmission ofa part ofthe M. maxillomandibularis. It is more oval, less circular than in Rattus norvegicus. There is an enlargement of the anterior face ofthe zygomatic arch for the origin ofthe anterior part ofthe M. masseter, pars profunda. The anterioredge ofthe zygomatic plate is straight. Atits ventral endthere is asmall tuberclethatmarks theoriginoftheM. masseter,pars superficialis andprobably alsothe M. masseter, pars reflexa. There is no spineonthedorsal end. In anteriorviewthe zygomatic plate ofL. conditortends tobe relativelybroaderdorsally ratherthan inL. apicalis. The anteriorpartofthe zygomatic archisnotbroadenedas inNotomys. In dorsal view the interorbital width is narrow compared with the width of the braincase which is expanded laterally. This is true forboth species butis moreextreme in L. conditor. There are no raised supraorbital ridges on the frontal bone, although it turns ventrally very abruptly to form the medial side ofthe orbit. The dorsal margin ofthe area oforigin ofthe M. temporalis closely corresponds to the suture between the parietal and squamosal. The incisive foramen is large and is located at the front ofthe palate, immediately posterior to the upper incisors. The anteriorpalatal foramina are long, extending forward fromjust posteriorto the anteriorend ofthe Ml three fourths ofthe distance to the upper incisors. They have the shape oflong ovals and are about equally contained by the maxillary and premaxillary bones. The median parts ofthe maxillaries and the premaxillaries are expanded to nearly fill the anterior three fourths ofthe foramina. The palate has shallow lateral grooves that connect the anterior and posterior palatine foramina. These grooves are separated from the alveoli by a ridge which is especially well defined in younger individuals. The posterior palatal foramina are oval in shape and are located opposite the M2. The postpalatine spine is largerthan that ofRattusnorvegicus. The cranial foramina are similar in their arrangement to those of Rattus norvegicus. The foramen ovale is about the same size in L. conditor as in R. norvegicus Proc.Linn.Soc.n.s.w., 121. 1999