Bull.Br.arachnol.Soc.(2010)15(3),69–78 69 A theridiosomatid spider from the Early gen.&sp.n.,isreferredtotheTheridiosomatidae.Thenew Cretaceous of Russia speciesextendsthegeologicalrecordofthefamily,andof the symphytognathoids, about 90 million years from the previousoldestrecordfromEoceneBalticamber. Paul A. Selden PaleontologicalInstituteandDepartmentofGeology, UniversityofKansas,1475JayhawkBoulevard, Introduction Lawrence,KS66045,USA;and The Theridiosomatidae are a small family of 85 DepartmentofPalaeontology, NaturalHistoryMuseum,LondonSW75BD species in 13 genera (Platnick, 2010). They have a cosmopolitan distribution but are concentrated in the tropics. Theridiosomatids are known colloquially as ray Summary spiders because their orb webs typically have widely AnewspiderfromEarlyCretaceous(130–140Ma)strata spaced radii. These delicate structures may be de- at the famous insect locality of Baissa, Transbaikalia, formed into a shallow cone by a tension line and are Russia,isdescribedfromfouradultfemaleandtwoadult male specimens. The new species, Eocoddingtonia eskovi constructed in moist, dark, mossy places. Coddington Figs.1–4: Eocoddingtoniaeskovigen.&sp.n.,PIN3064–8593,holotypefemale.1Photographofpart,PIN3064–8593a;2Explanatorydrawing ofpart;3Photographofcounterpart,PIN3064–8593b;4Explanatorydrawingofcounterpart. 70 CretaceousTheridiosomatidae (1986) provided a review of the family and a cladogram million years in age, thus extend the fossil record of the for the genera. Theridiosomatidae are small to minute family threefold to the early Cretaceous. spiders (less than 3mm body length) with short- to medium-length legs and relatively large male palpal Material and methods bulbs. Synapomorphies for the family proposed by Coddington (1986) are a pair of pits on the anterior The specimens described here came from the famous margin of the sternum near the base of the labium Baissa fossil insect locality of the Buryat Autonomous (absent from the Neotropical genus Chthonos), connate Republic, western Transbaikalia, Russia (Zherikhin spermathecae (except in the Chinese Coddingtonia: etal.,1999).Themainlocalityliesontheleftbankofthe Milleretal.,2009),andelongatedorsaltrichobothriaon Vitim river, 8km below the mouth of the Baissa river, the tibia of the fourth leg. about 60km from the village of Romanovka in the Fossil theridiosomatids are known from Eocene Eravnensky District. Stratigraphy is the Zazinskaya Baltic, Oligocene Bitterfeld and Miocene Dominican Formation, which is dated as Lower Cretaceous, Republic ambers (Wunderlich, 1988, 2004), of 44–49 Berriasian–Valanginian (130–140Ma) (Vršanský et al., million, 25.3–23.8 million and 16 million years old 2002).Fossilinsectsoccurthroughoutthesectioninthe respectively(Dunlop&Mitov,2009;Penney,2008).The finer grained rocks; they are especially well preserved in specimens described here, which are about 130–140 the marls, which represent lacustrine deposits. More Figs.5–8: Eocoddingtoniaeskovigen.&sp.n.,paratypefemales.5PIN3064–8591,compositephotographofpartandcounterpart;6Explanatory drawingofPIN3064–8591;7PIN4210–5461,compositephotographofpartandcounterpart;8ExplanatorydrawingofPIN4210–5461. P.A.Selden 71 than10,000fossilinsects,oftenofexcellentpreservation The spider specimens are preserved as organic ma- state, have been collected at Baissa (Zherikhin et al., terial in fine clayrock, together with abundant commi- 1999), but only 22 spiders to date. One feature of the nuted carbonised plant fragments. The fossils were locality is the climatic change, from humid to dry then studied using a Wild MZ16 stereomicroscope, drawn back to humid again, as reflected in changes in the using a camera lucida attachment, and photographed composition of the fossil insect assemblages (Vršanský with a Canon 5D Mk II digital camera attached to the et al., 2002). The spiders described here all came from microscope.Photographsweretakenwiththespecimens layer number 31, which has also yielded abundant under ethanol to enhance contrast. High resolution insects, ostracodes, plants, gastropods, and tetrapods, composite photographs were prepared using Adobe including feathers, and is among the layers with a Photoshop CS4 Professional. Drawings and photo- humid climate (Zherikhin et al., 1999; Vršanský et al., graphs were prepared for publication using Adobe 2002). Illustrator CS4 and Adobe InDesign CS4 on an Apple Figs.9–12: Eocoddingtoniaeskovigen.&sp.n.,paratypefemale,PIN4210–5462.9Photographofpart,PIN4210–5462a;10Explanatorydrawing ofpart;11Photographofcounterpart,PIN4210–5462b;12Explanatorydrawingofcounterpart. 72 CretaceousTheridiosomatidae MacBook Pro computer operating under Mac OS X. part of fossils can be superimposed to reveal more One advantage of computer manipulation is that better complete morphological information, which would depthoffocuscanbeachievedbystackingimagestaken otherwise be separated on two different slabs; see, for at different levels of focus. Moreover, part and counter- example, Figs. 5, 6 17, 23, 32–35. All measurements are Figs.13–16: Eocoddingtoniaeskovigen.&sp.n.,sternaandspinnerets.13Holotypefemalepart,PIN3064–8593a,sternum,arrowsshowpossible positions of gland openings; 14 Composite photograph of paratype female, PIN 4210–5462, sternum; 15 Allotype male part, PIN 4210–5463a,sternum,arrowsshowpossiblepositionsofglandopenings;16Holotypefemalepart,PIN3064–8593a,spinnerets,note spinningfieldwithnotchandspigotsonleftAS. P.A.Selden 73 inmm;scalelinesinfiguresare1mm.Abbreviations:I, onespecimen(PIN4210–5461)itwholly,andinanother II, III, IV=leg numbers, AS=anterior spinneret, at= partly (PIN 4210–5462), covers the carapace. In many anal tubercle, car=carapace, ch=chelicera, cx=coxa, compression fossils of spiders the chelicerae extend ep=epigyne, fe=femur, lb=labium, MS=median spin- forwards and appear to be porrect; in these theridio- neret, mt=metatarsus, mx=maxilla, op=opisthosoma, somatids, however, the chelicerae are compressed in a pa=patella, Pd=pedipalp, PS=posterior spinneret, st= verticalorientation(PIN3064–8593)orarefoldedback- sternum, ta=tarsus, ti=tibia, trich=trichobothrium. wardsandpointtowardsthesternum(PIN4210–5462a). Joint refers to the articulation between leg articles. Manyfeaturesoccuronbothpartandcounterpart,and itisnotpossibletodefinepartandcounterpartasdorsal and ventral. For example, epigynes (Figs. 28–31) are Morphological interpretation preservedonbothslabs,andthesetalorientationonthe Thetypeseriesconsistsoffouradultfemalesandtwo opisthosomashowsbothanterior–posterior(dorsal)and adult males. Eyes are rarely preserved in compression lateral (ventral) directions. The preservation is of suffi- fossil spiders, and these specimens are no exception; ciently high quality that even such fine structures as suggestions of eyes cannot be confirmed. The opistho- trichobothrial hairs (Figs. 17–22) and epigynal internal soma is interpreted to have been globose in life, and in structures(Fig.30)canbeseen.Theinterpretationofthe Figs.17–22: Eocoddingtoniaeskovigen.&sp.n.,legsoffemales.17Compositephotographofparatypefemale,PIN3064–8591,legIIIpatellato tarsus;18Holotypefemalepart,PIN3064–8593a,legIpatellatotarsus;19Holotypefemalepart,PIN3064–8593a,legIVtibia;20 Paratype female counterpart, PIN 3064–8591b, leg II tibia; 21 Paratype female counterpart, PIN 3064–8591b, leg IV tibia; 22 Holotypefemalepart,PIN3064–8593a,legIIImetatarsusandtarsus. 74 CretaceousTheridiosomatidae epigyne is difficult, but the excellent preservation means morphology of the two large sclerites (Figs. 33–36) that more morphology can be inferred than is usually resembles that of the tegulum and/or conductor typical the case in matrix-preserved spider fossils. From com- of theridiosomatid males (e.g. Miller et al., 2009: fig. 2). parisonofFigs.28and30,whicharethebest-preserved Hence, these specimens are considered to be conspecific examples, it can be seen that a subtrapezoidal median with the females. lobe is flanked by dark areas. In Fig. 30, faint circular canals are shown in the postero-lateral corners of the median lobe, apparently originating from dark spots on Family Theridiosomatidae Simon, 1881 theposteriorborder;theseareinterpretedascopulatory ducts coming from openings on the posterior border. Remarks:Thespidersarereferredtothisfamilyonthe The spermathecae are most likely in the region of the followinglinesofevidence.Thehabitusisthatofasmall dark areas; indeed, circular structures can also be made araneoid: globular opisthosoma with epigyne close to out in these regions on Fig. 30 (see Fig. 32). Thus, the spinnerets,i.e.spinneretsventralratherthanterminalon spermathecae are presumed to be separate rather than opisthosoma, and opisthosoma held well forward over connate. the prosoma, as evidenced by it wholly or mostly Identification of males is more problematic. Speci- covering the carapace; lack of claw on female pedipalp mens PIN 4210–5463 and PIN 3064–8594 are adult tarsus (Figs. 10–12); numerous trichobothria on all males of similar size and habitus to the females, with tibiae; single trichobothrium in proximal position on globular opisthosomas, similar sternal shape (in PIN metatarsus (Figs. 18, 22); the conformation of the ster- 4210–5463, designated here as the allotype), tibial tri- num and labium is as that seen in other theridiosoma- chobothria, and tarsal claw pattern. The large size and tids,thoughthepresenceofsternalpits,whilesuggested compact,globularshapeofthecymbialpartsofthemale in some specimens (Figs. 13–15) cannot be confirmed. is typical of Theridiosomatidae. It is not possible to Thedistal(cymbial)partsofthemalepedipalparelarge, assign names accurately to the palpal sclerites, but the compact and globose. Figs.23–27: Eocoddingtonia eskovi gen. & sp. n., tarsi. 23 Composite photograph of allotype male, PIN 4210–5463, legs IV tarsi; 24 Paratype femalepart,PIN4210–5461a,legIItarsus;25Paratypefemalepart,PIN3064–8591a,legIIItarsus;26Allotypemalecounterpart, PIN4210–5463b,legIIItarsus;27Holotypefemalepart,PIN3064–8593a,legItarsus. P.A.Selden 75 Genus Eocoddingtonia gen. n. 3064–8591, part and counterpart; adult female, PIN 4210–5461, part and counterpart; adult female, PIN Type species: Eocoddingtonia eskovi sp. n. 4210–5462,partandcounterpart;adultmalePIN3064– Etymology: The name Eocoddingtonia is derived from 8594,partandcounterpart.Allspecimensareheldinthe the Greek eos, dawn, and Coddingtonia, a genus of Palaeontological Institute of the Russian Academy of Theridiosomatidae which the fossil genus resembles. Sciences, Moscow (PIN), and came from the Baissa Diagnosis: Eocoddingtonia differs from all other the- locality on the left bank of the Vitim river, c.60km ridiosomatids except Coddingtonia by having separate from the village of Romanovka, Buryat Autonomous spermathecae in the female epigyne. The new genus Republic, Transbaikalia, Russia; Zazinskaya Forma- differsfromCoddingtoniabyitsgloboseabdomen.With tion, Lower Cretaceous (Berriasian–Valanginian). a body length of around 4mm, Eocoddingtonia is the Description: Female: See Table 1 for measurements. largest known theridiosomatid. Carapace slightly longer than wide, elliptical in outline. Chelicera (inc. fang) about twice as long as wide; fang Eocoddingtonia eskovi sp. n. (Figs. 1–36) short (Figs. 9–10). Pedipalp short; tibia and tarsus with Etymology: After Dr Kirill Eskov, PIN, Moscow. numerous curved macrosetae; tibia with cluster of tri- Diagnosis: As for the genus. chobothria (Figs. 11–12); tarsus without a claw. Leg Material: Holotype: adult female, PIN 3064–8593, formula I, II, IV, III, all legs with numerous curved part and counterpart; allotype: adult male, PIN 4210– macrosetae:dorsalrowonfemur,oneonpatella,proxi- 5463,partandcounterpart.Paratypes:adultfemalePIN maloneontibia.Alltibiaewithclusteroftrichobothria \8593 \8591 \5461 \5462 _8594 _5463 Bodylength 4.52 3.76 3.80 Carapacelength 1.64 1.38 Carapacewidth 1.53 1.26 Length/widthratio 1.07 1.10 Sternumlength 0.71 0.71 Sternumwidth 0.63 0.65 Length/widthratio 1.13 1.09 Labiumlength 0.23 Labiumwidth 0.32 Labiumlength/widthratio 0.72 Cheliceralength 0.65 Chelicerawidth 0.32 Length/widthratio 2.03 Labiumlength 0.30 Pedipalptibia 0.54 0.51 Pedipalptarsus 0.59 0.60 LegIfemur–tarsus 5.74 4.86 5.25 >3.15 LegIfemur 1.64 1.56 LegIpatella 0.60 0.43 0.45 LegItibia 1.52 1.40 1.50 1.04 1.41 LegImetatarsus 1.38 1.38 1.23 1.00 LegItarsus(inc.claw) 0.84 0.80 0.81 0.62 LegIIfemur–tarsus 4.65 3.86 4.36 4.00 LegIIfemur 1.70 1.50 LegIIpatella 0.70 0.50 0.51 0.40 0.34 0.40 LegIItibia 1.15 0.95 1.06 0.98 0.94 1.02 LegIImetatarsus 1.04 1.00 1.05 0.95 0.81 1.08 LegIItarsus(inc.claw) 0.72 0.73 0.75 0.75 0.52 0.70 LegIIIfemur–tarsus 3.30 3.14 >2.56 LegIIIfemur 1.30 0.95 0.84 0.97 LegIIIpatella 0.40 0.38 0.40 0.32 0.35 LegIIItibia 0.68 0.60 0.65 0.48 0.50 LegIIImetatarsus 0.66 0.60 0.55 0.53 0.59 LegIIItarsus(inc.claw) 0.50 0.50 0.53 0.48 0.44 LegIVfemur–tarsus 4.36 3.34 LegIVfemur 1.50 1.28 1.30 LegIVpatella 0.52 0.52 0.37 LegIVtibia 0.94 0.94 0.95 0.82 LegIVmetatarsus 0.90 0.86 0.90 0.84 LegIVtarsus(inc.claw) 0.60 0.56 0.60 0.60 Opisthosomalength 3.10 2.78 2.27 2.81 1.77 Opisthosomawidth 2.90 2.65 2.54 2.70 1.78 Opisthosomalength/widthratio 1.07 1.05 0.89 1.04 0.99 Table1: Specimenmeasurements(inmm). 76 CretaceousTheridiosomatidae in approximately two rows dorsally; length of some Epigyne (Figs. 28–32) about twice as wide as long, trichobothrial hairs on tibia IV at least twice that of with broadly recurved anterior border, slightly pro- tibialwidth(Fig.21).MetatarsiI–IIIwithsingletricho- curvedposteriorborder.Longsetaesituatednearcentre bothriuminproximalhalf.Tarsiwiththreeclaws;paired ofanterioredgeofepigyne.Subellipticallaterallobesof claws with numerous blade-like teeth (Fig. 24); median epigyne extend from lateral corners along anterior bor- clawaslongaspairedclaws,stronglyrecurved(Fig.25); dertowardsmidline,butseparatedbyaboutone-sixthof few S-curved, serrate bristles distally on tarsi (Fig. 27). width of epigyne; lateral lobes with darker pigmented Sternum cordate, lateral borders slightly scalloped be- areas anteriorly and, especially, posteriorly, where they tween coxae, posteriorly protruded between coxae IV presumablycoverspermathecae.Subtrapezoidalmedian into rectangular profile; possible sternal pit openings at lobe of epigyne smooth, unpigmented and hairless, base of labium (Figs. 13–14). Labium wider than long, shorter, anterior border separates lateral lobes, posteri- with well-defined suture with sternum (Figs. 13–14). orly diverging lateral borders adjacent to posterior bor- Opisthosoma slightly wider than long, globose, setose; ders of lateral lobes, long posterior border forms epigyne and spinnerets close together ventrally on anterior edge of epigynal furrow. Presumed copulatory opisthosoma.Spinneretgroup(Fig.16)withequal-sized openings seen as dark spots at posterior lateral corners anterior (AS) and posterior (PS) spinnerets, small me- ofmedianlobe,leadingtocircularductsbeneathmedian dian (MS) spinnerets. AS and PS conical with elliptical lobeandadjacenttodarkareasoflaterallobes(Fig.30). cross-section; AS shows very short distal segment with Male: See Table 1 for measurements. Carapace and notch,bearingspigots(Fig.16).Colulusmaybepresent chelicerae not visible in either specimen. Leg formula I, but not visible. II,IV,III.Numerousmacrosetaeonfemoratometatarsi Figs.28–31: Eocoddingtoniaeskovigen.&sp.n.,femaleepigynes.28Holotypefemalepart,PIN3064–8593a;29Holotypefemalecounterpart,PIN 3064–8593b;30Paratypefemalecounterpart,PIN4210–5462b;31Paratypefemalepart,4210–5462a;32ExplanatorydrawingofPIN 4210–5462b. P.A.Selden 77 Figs.33–36: Eocoddingtoniaeskovigen.&sp.n.,males.33Compositephotographofallotype,PIN4210–5463;34ExplanatorydrawingofPIN 4210–5463;35Compositephotographofparatype,PIN3064–8594;36ExplanatorydrawingofPIN3064–8594. 78 CretaceousTheridiosomatidae of all legs; tibiae of all legs with cluster of trichobothria Acknowledgements (Figs. 33–36). Tarsi with three claws; median claw as IthankKirillEskov,PIN,Moscow,forprovidingthe long as paired claws, strongly recurved (Figs. 23, 26); specimens for study and helpful discussions. few S-curved, serrate bristles distally on tarsi (Figs. 23, 26). Sternum (Fig. 15) cordate, lateral borders slightly scallopedbetweencoxae,posteriorlyprotrudedbetween References coxae IV into rectangular profile; possible sternal pit openings at base of labium. Labium wider than long, CODDINGTON, J. A. 1986: The genera of the spider family withwell-definedsuturewithsternum(Fig.15).Opistho- Theridiosomatidae.Smithson.Contr.Zool.422:1–96. DUNLOP, J. A. & MITOV, P. G. 2009: Fossil harvestmen (Arach- soma with sparse, fine setae and long, thin macrosetae. nida, Opiliones) from Bitterfeld amber. In P. Stoev, J. A. Pedipalpwiththinfemur;cymbiumandenditesshowing Dunlop & S. Lazarov (eds), A life caught in a spider’s web. a compact, globose morphology. PapersinarachnologyinhonourofChristoDeltshev.ZooKeys 16:347–375. GRISWOLD, C. E., CODDINGTON, J. A., HORMIGA, G. & Discussion SCHARFF, N. 1998: Phylogeny of the orb-web building spi- ders(Araneae,Orbiculariae:Deinopoidea,Araneoidea).Zool. The genus Coddingtonia was erected by Miller et al. J.Linn.Soc.123:1–99. (2009) for a Chinese theridiosomatid with separate, MILLER, J. A., GRISWOLD, C. E. & YIN, C. M. 2009: The rather than connate, spermathecae. Miller et al. (2009) symphytognathoid spiders of the Gaoligongshan, Yunnan, gave no indication of how their new genus might be China (Araneae, Araneoidea): systematics and diversity of related to other theridiosomatids. Since all other extant micro-orbweavers.ZooKeys11:9–195. PENNEY, D. 2008: Dominican Amber Spiders. Siri Scientific Press, theridiosomatids have connate spermathecae and other Manchester.178pp. symphatognathoids and araneoids have separate sper- PENNEY,D.&SELDEN,P.A.2002:Theoldestlinyphiidspider,in mathecae (Griswold et al., 1998), the connate state is Lower Cretaceous Lebanese amber (Araneae, Linyphiidae, apomorphic within Theridiosomatidae and both Cod- Linyphiinae).J.Arachnol.30:487–493. dingtonia and the fossil Eocoddingtonia show the PLATNICK, N. I. 2010: The world spider catalog, version 10.5. <http://research.amnh.org/entomology/spiders/catalog/ plesiomorphic state of this character. The globose index.html> opisthosoma, which serves to separate the fossil Eocod- SELDEN,P.A.&PENNEY,D.2010:Fossilspiders.Biol.Rev.85: dingtoniafromCoddingtonia,provideslittlephylogenetic 171–206. information because the globose abdomen occurs SIMON,E.1881:LesarachnidesdeFrance5(1):1–180.Paris. commonly in other small araneoids and not in all VRS{ANSKYu, P., MOSTOVSKI M. B., BAZYLEV B. A. & theridiosomatids.GiventhepresentknowledgeofEoco- BUGDAEVAE.2002:EarlyCretaceousclimatechangessug- gestedonthebasisofcockroachwingvariations.InProceed- ddingtonia, its position within the Theridiosomatidae ings of the XVII Congress of the Carpathian-Balkan wouldbeonthestemofthefamily,eitherassistertoall Geological Association, Bratislava, September 1st–4th, 2002. other theridiosomatids or to all except Coddingtonia. Geol.Carpath.53(Specialissue):1–5. Griswold et al. (1998) placed Theridiosomatidae as WUNDERLICH, J. 1988: Die fossilen Spinnen im dominikanischen sister to a clade including Mysmenidae, Symphytog- Bernstein.Beitr.Araneol.2:1–378. nathidaeandAnapidae.Thefossilrecordsoftheseother WUNDERLICH, J. 2004: The fossil spiders of the family Anapidae s. l. (Araneae) in Baltic, Dominican and Mexican amber and symphatognathoid families extend no older than theirextantrelatives,withthedescriptionofanewsubfamily Eocene: Baltic amber for Mysmenidae and Anapidae Comarominae.Beitr.Araneol.3:1020–1111. (Wunderlich, 2004), and no record of Symphytognathi- ZHERIKHIN, V. V., MOSTOVSKI, M. B., VRS{ANSKYu, P., dae (see Selden & Penney, 2010). Accordingly, the BLAGODEROV,V.A.&LUKASHEVICH,E.D.1999.The symphytognathoids as a clade would be expected to uniqueLowerCretaceouslocalityBaissaandothercontempor- aneousfossilinsectsitesinNorthandWestTransbaikalia.In extend back at least to the Early Cretaceous. This was P.Vršanský(ed.),ProceedingsoftheFirstPalaeoentomological already predicted by the occurrence of Linyphiidae in Conference, Moscow, 1998: 185–191. AMBA Projects, Bratis- the Early Cretaceous (Penney & Selden, 2002). lava,Slovakia.