New Studies of Decapod Crustaceans from the Upper Jurassic Lithographic Limestones of Southern Germany
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Contributions to Zoology, 72 (2-3) 173-179 (2003) SPB Academic Publishing bv, The Hague New studies of decapod crustaceans from the Upper Jurassic lithographic limestones of southern Germany Günter Schweigert¹ & Alessandro Garassino² 2 1 Staatliches Museum fiir Naturkunde, Rosenstein I, D-70I91 Stuttgart, Germany; Museo civico di Storia naturale, Corso Venezia 55, 1-20121 Milano, Italy Keywords:: Crustacea, Decapoda, lithographic limestones, Upper Jurassic, Solnhofen, fossil record, diversity Abstract Introduction The Upper Jurassic lithographic limestones ofsouthern Germany TheUpper Jurassic lithographic limestones in south- have long been known for their exceptional preservation of ern Germany outcrop at numerous localities are of decapod crustaceans (Glaessner, 1965), similar to the Upper and differentage setting and span an area of sev- Cretaceous of Lebanon (Hakel, Hadjoula) and the still poorly eral hundreds of kilometers (Fig. 1, Table 1) with known Callovian strataat La Voulte-sur-Rhône (France). In these localities in the Frankische Alb often summarized non-bioturbatedlimestones, the decay of decapod skeletons is that mineralized and reduced, so besides the heavily chelae as ‘Solnhofen Lithographic Limestones’. Many fos- often even delicate structures such as pleopods and carapace sils, both in old and new collections (fossil traders), antennae are preserved. Recently, new decapod material has which is are labeled ‘Solnhofen’, highly mislead- been obtained from both scientific and commercial excavations, ing and precludes recognition of evolutionary trends in part in reopened lithographic limestone quarries. I. Fossiliferous lithographic limestones in southern Germany. Downloaded from Brill.com09/24/2021 08:25:23AM via free access 174 G. Schweigert & A. Garassino - New studies of Jurassic limestones from Germany Table I. Age assignments for decapodcrustacean-bearing litho- in the Regensburg (Ebenwies) area. An important limestones in southern graphic Germany. is that of where thin locality nearby Brunn, a paper shale of Late in Kimmeridgian age deposited a very Locality Stratigraphic age shallow lagoon surroundedby calcareous green algae Mornsheim, Daiting Early Tithonian, Hybonotum meadows, coral reefs, and small islands, is exposed. Zone, uppermostpart is the Slightly younger (still Late Kimmeridgian) Solnhofen, Langenaltheim Early Tithonian, Hybonotum Nusplingen Lithographic Limestone in SW Ger- Zone, upper part famous for its richness in fossil Eichstatt, Zandt Early Tithonian, Hybonotum many, sharks as Zone, lower well This part as decapod crustaceans. was deposited Painten, Painten, Schamhaupten, Kimmeridgian/Tithonian in surrounded a c. 100 m deep lagoon, by sponge- Ochselberg boundary beds microbial mounds and islands. East of Eichstatt Nusplingen Late Kimmeridgian, Beckeri (Frankische Alb), several localities have Zone, Ulmense Subzone yielded crustaceans from limestones Brunn LateLate Kimmeridgian, Beckeri decapod lithographic Zone, Subeumela Subzone spanning the Kimmeridgian/Tithonian boundary, LateLate Ebenwies/Naab Kimmeridgian, Pseudo-IPseudo- later depending on a definition of the lower boundary mutabilismutahilis Zone of the Tithonian. Excavations by staff members of the Jura-Museum Eichstatt in the siliceous litho- graphic limestones of Schamhaupten have resulted and local differences in paleoecology. Only an in a proliferation of new decapod crustacean mate- in-depth knowledge oflocal lithologies allows rec- rial. In contrast, the lithographic limestones ofZandt ognizing the exact provenance of material. Strati- and the more biodetritic limestones of the nearby well-documented material have graphically has recently Ochselberg yielded a diverse, excellently pre- been collected at several scientific excavations, and served decapod crustacean fauna, including sev- there are a number of private collectors who focus eral new taxa. Other faunas of an age similar to on special sites. those ofZandt are from quarries north of Eichstatt, e.g., Blumenberg, Schernfeld, Wintershof. Many ‘old’ taxa were first described from this area. Results The classic lithographic limestones of Solnhofen and are of Tithonian thus Langenaltheim Early age, Repositories of material referred to here are as are younger than those of the Eichstatt area. Apart from of follows: BSPM - Baycrische Staatssammlung fur mass occurrences planktonic crinoids, these limestones in fossils. Vertebrate fau- Paliiontologie und historische Geologic, Miinchen; are very poor - nal and other data more JME Jura-Museum, Eichstatt; NHM - The Natu- suggest a pelagic setting. ral History Museum, London; SMNS - Staatliches Both the Eichstatt and Solnhofen sections comprise Museum fur Naturkunde, Stuttgart. micritic limestones deposited in larger, shallow Schweigert et al. (1996) and Schweigert (2000) basins, the margins of which are poorly known, worked out the biostratigraphy of the Upper Kim- since at present only the purest limestones in the meridgian, but it should be noted that our knowl- central basins are quarried. The Solnhofen Litho- edge of ammonite faunal succession of the Tithonian graphic Limestone Formation is usually overlain Stage is still in its infancy. The oldest lithographic by a hardground or another discontinuity followed the limestones, in part not yet dated precisely, occur by more biodetritic and silica-rich Moernsheim Fig. 2. A, Rosenfeldia oppeli (Woodward), Solnhofen Lithographic Limestones (upper Eichstatt Formation, Lower Tithonian), most from likely Eichstatt area (NHM 44886, holotype, Haberlein Colin). B, Erymastacus n. sp., Nusplingen Lithographic Limestone Formation (Upper Kimmeridgian), Nusplingen quarry (SMNS 64872,2002excavation). C, Megachelafrickhingeri Schweigert, Solnhofen Limestones Peneeid Solnhofen Lithographic (Lower Tithonian), Eichstatt (SMNS 64933, paratype, LudwigColin). D, (n. gen., n. sp.), Limestones Lithographic (PaintenFormation,Ochselberg Member,Kimmeridgian/Tithonian boundary beds), Ochselberg near Breitenhill (Burger Colin, Bad Hersfeld). All scale bars equal 10 mm. Downloaded from Brill.com09/24/2021 08:25:23AM via free access Contributions 72 - to Zoology, (2-3) 2003 175 Downloaded from Brill.com09/24/2021 08:25:23AM via free access 176 G. Schweigert & A. Garassino - New studies of Jurassic limestonesfrom Germany Downloaded from Brill.com09/24/2021 08:25:23AM via free access Contributions to Zoology, 72 (2-3) - 2003 177 which has also Formation, yielded numerous de- served taxa came to light, which often allowed a capod crustaceans. revision of these. Future research into decapod crustaceans from the lithographic limestones of southern Germany has modern revision of the Discussion many aspects. Firstly, a is in which the taxa necessary, stratigraphic age, provenance, and taphonomy is included. Most of The bulk of the decapod crustaceans faunas of the material the type is still available, but some taxa lithographic limestones in southern Germany was in are fact nomina dubia. The bulk of the types described in nineteenth century monographs (von from the Frankische Alb are in museums in Miinchen Schlotheim, 1820,1822; von Munster, 1839;Oppel, (Munster and Oberndorfer collections) and in Ber- 1861, 1862). Discoveries of extant eryonids dur- lin (von Schlotheim and Redenbacher collections). ing deep-sea expeditions triggered the study of fossil Few others survive in the Senckenberg Museum at forms (e.g., von Knebel, 1907). In the first half of Frankfurt am Main (H. von Meyer Colin), at the the twentieth century, both Beurlen and Glaessner Geiseltal Museum (Halle/Saale; Germar Colin), and almost ignored decapods from the lithographic lime- at the Natural History Museum (London; Haberlein stones in their scientific work. In recent years, c. Colin). The types from Nusplingen are almost ex- 56 valid taxa from the Frankische Alb and four others clusively housed at the Staatliches Museum fiir from the isolated locality ofNusplingen (Schwaben) Naturkunde Stuttgart (O. Fraas Colin). have have been described, and only a few of these For many taxa, lectotypes have never been des- been revised Forster (1966, 1967, 1973, briefly by and there still ignated, are some doubtful genera 1977). Following his untimely death in 1987, the and species. New topotypes in better preservation study of fossil decapod crustaceans from Germany and the use of ultraviolet light (Fig. 2A-D) often declined. allow a more detailed redescription. Unfortunately, From the late 1990s scientific excava- onwards, the use of ultraviolet light does not work with de- tions both in eastern Bayern (Brunn), the southern capods from Zandt, which otherwise includes the Alb Frankische (Schamhaupten) and at Nusplingen, material. best Secondly, a larger amount of new has rekindled research activities (Polz, 1999, 2000; taxa, approximately 15-20, still awaits description, Schweigert 2001 a,b,c; Schweigert & Dietl, 1999; documenting most orders of Jurassic decapods. Some & Schweigert et al., 2000; Schweigert Roper, 2001). of them are easily assigned to described genera, It became obvious that both for paleoenvironmental while others are completely new and demonstrate reconstructions and it is the systematic paleontology, incompleteness of our present knowledge of to the fossil material of each necessary separate decapod diversity in the Upper Jurassic. In several Another is the mono- locality. strong pulse given by groups, even in those held to be conservative, evo- graphic documentationof‘Solnhofen’ fossils stored trends have been in the lutionary