The Höör Sandstone is a geologic formation in Skåne County, southern Sweden. It is Early Jurassic (Hettangian-Pliensbachian) in age. This unit outcrops in central Skane on a few isolated exposures, being traditionally subdivided into the lower “millstone” (“kvarnstenen”) and the upper “buildingstone”. The lowermost layers where also claimed to host Rhaetian strata, however latter works suggested that the layers devolved as red beds, were part of the new Hörby Formation, thus delimitating the Höör sandstone to the lower Jurassic. It has been assumed to be limited to Hettangian-Sinemurian layers, yet recent palynological analysis suggest the uppermost section is of Pliensbachian age, underlying and maybe interacting with the younger volcanic deposits. The Höör sandstone represents a mostly fluvial unit with a rich collection of fossil plants, yet also includes brackish bivalves in some layers, pointing to marine ingressions locally.
Members Stanstorp member This member represents the older layers of the formation, being exposed in the abandoned stanstorpsgraven quarry and in the Vittseröd area. The member is mainly composed by sandstone and has abundant plants fossils, with both allochthonous plant fragments and plant roots indicating vegetation in situ (palaeosols). The layers suggest several types of fluvial and/or coastal depositions, from dunes and river banks to beach deposits, where the palaeocurrent directions are clear generally from the north-east to the south-west. This section hosts abundant conglomerate intercalations, with the lower ones formed by mud fragments and the uppers with distant source material, both abundant on wood fragments, some of them up to 20 cm in diameter.
Vittseröd member The youngest member is composed by finer-grained and much better sorted sandstones, with limited abundance of mudstones and plant fragments small and limited to a few horizons. The presence of silt and mature quartz arenites, well sorted and fairly well rounded derived from strongly altered feldspars, shows that this member hosted a high-energy environment, one where tidal currents have been invoked for the modification of fine-grained sandstones, linked with the changes of the Laurasian Seaway. The upper parts of this unit are influenced by the initial pulse of the Pliensbachian coeval vulcanism with heavy volcanic minerals in the uppermost layers.
Fauna Ichnofossils
Lockeia siliquaria (Bivalves) Planolites annularis (Polychaetes) Planolites montanus (Polychaetes) Diplichnites isp. (Xiphosurans, Insects, Arachnids) Teichichnus isp. (Polychaetes, Echiurans, Holothurians.) Skolithos isp. (Polychaetes, Phoronidans) Monocraterion tentaculatum (Polychaeta, Sipuncula, Enteropneustans & Echiurans) Rhizocorallium isp. (Polychaeta, Sipuncula, Enteropneustans & Echiurans) Aulichnites isp. (Gastropods) Diplocraterion parallelum (Polychaeta, Sipuncula, Enteropneustans & Echiurans)
Bivalves Genus Species Location Stratigraphic position Material Notes ImagesAviculaA. inaequivalvisVittserödVittseröd memberIsolated ShellsA Scallop, member of Pectinidae inside Pectinida. The local material assigned to this genus is now lostCardiniaC. folliniStanstorp Vittseröd DagstorpVittseröd memberIsolated ShellsA clam, member of Cardiniidae inside Carditida. This faunal aggrupation occurs together with abundant foliar remains and are equivalent to the Brandsberga erratics, which was closer to the mouth of the bay developed in the region, as it proves the find on its sandstone of more clear marine fauna.LiostreaL. hisingeriVittserödVittseröd memberIsolated ShellsAn oyster, member of Ostreidae inside Ostreida. The most common Bivalve found locally, indicator of increased salinity levels on the Hettangian layers.PectenP. sp.Vittseröd Vittseröd memberIsolated ShellsA Scallop, member of Pectinidae inside Pectinida.
Arthropoda Genus Species Location Stratigraphic position Material Notes ImagesAngelinellaA. angeliniKulla GunnarstorpStanstorp MemberElytronsA beetle, incertae sedis Archostemata inside Coleoptera.MesolimulusM.? nathorstiStanstorpVittseröd Member SMNH Ar33179, a possible prosomal sectionA horseshoe crab, member of the Limulidae inside Xiphosura. This fragment has been considered to be a Limulus or Mesolimulus prosomal shield, but due to the limited and fragmentary nature some authors referred to it as ?Chelicerata incertae sedis.ParacurculionitesP. parvulusNorth of SofieroStanstorp MemberElytronsA beetle, incertae sedis Archostemata inside Coleoptera.
Flora Genus Species Stratigraphic position Member Material Notes ImagesAnomozamitesA. minor A. intermediumVittseröd Stanstorpsgraven Per Pålssons grav Ormanäsgraven Kullans stenbrottVittseröd MemberLeafletsAffinities with Williamsoniaceae inside Bennettitales. CtenisC. nilssonii C. minuta C. latepinnata C. laxaVittseröd Stanstorpsgraven Per Pålssons gravVittseröd MemberLeafletsAffinities with Cycadales inside Cycadopsida. CladophlebisC. svedbergii C. scoresbyensis C. cf. nebbensis C. cf. spectabilis C. arguta C. sublobata C. sewardii C. divaricataStanstorpsgraven Ormanäsgraven Kullans stenbrott DagstorpStanstorp MemberIsolated pinnaeAffinities with Osmundaceae inside Osmundales. ClathropterisC. meniscioidesVittseröd Stanstorpsgraven Per Pålssons grav Ormanäsgraven Kullans stenbrottStanstorp Member Vittseröd MemberIsolated pinnaeAffinities with Dipteridaceae inside Polypodiales. CycadolepisC. giganteus C. blomquistiVittseröd Stanstorpsgraven Per Pålssons gravVittseröd MemberLeafletsAffinities with Cycadeoidaceae inside Bennettitales. DictyophyllumD. exileStanstorpsgraven Ormanäsgraven Kullans stenbrottStanstorp MemberIsolated pinnaeAffinities with Dipteridaceae inside Polypodiales. Dictyophyllum is a common Dipteridacean genus of the mid-MesozoicElatocladusE. cephalotaxoides E. confertaVittseröd Stanstorpsgraven Per Pålssons grav Ormanäsgraven Kullans stenbrottStanstorp Member Vittseröd MemberFragmentary axis compressions with preserved leavesAffinities with Sequoioideae inside Cupressales. EquisetitesE. laevis E. gracilisOrmanäsgraven Stanstorpsgraven Per Pålssons gravStanstorp MemberStemsAffinities with Equisetaceae inside Equisetales. GinkgoitesG. troedsonii G. obovatus G. marginatusVittseröd Stanstorpsgraven Per Pålssons grav Ormanäsgraven Kullans stenbrottStanstorp Member Vittseröd MemberLeave CompressionsAffinities with Ginkgoaceae inside Ginkgoales. HausmanniaH. forchhammeri H. dentata H. lasciniataVittseröd Stanstorpsgraven Per Pålssons grav Ormanäsgraven Kullans stenbrottStanstorp Member Vittseröd MemberIsolated pinnaeAffinities with Dipteridaceae inside Polypodiales. LepidopterisL. ottonisStanstorpsgraven OrmanäsgravenStanstorp MemberIsolated pinnaeAffinities with Peltaspermaceae inside Pteridospermatophyta. Indicator or reworked Rahetian layers.NilssoniaN. münsteri N. acuminataVittseröd Stanstorpsgraven Per Pålssons gravVittseröd MemberLeafletsAffinities with Cycadeoidaceae inside Bennettitales. PeltaspermumP. rotulaStanstorpsgraven OrmanäsgravenStanstorp Member Vittseröd MemberIsolated pinnaeAffinities with Umkomasiaceae inside Pteridospermatophyta. PodozamitesP. lanceolatus P. angustifolius P. cuspiformisVittseröd Stanstorpsgraven Per Pålssons grav Ormanäsgraven Kullans stenbrottStanstorp Member Vittseröd MemberIsolated LeavesAffinities with Krassiloviaceae inside Voltziales. The local Podozamites show a rather great range of growth, reflecting tropical to subtropical conditions.PtilozamitesP. blasii P. carlsonii P. heeri P. nilssoniiVittseröd Stanstorpsgraven Per Pålssons grav Ormanäsgraven Kullans stenbrottStanstorp Member Vittseröd MemberIsolated pinnaeAffinities with Umkomasiaceae inside Pteridospermatophyta. PseudoctenisP. floriniiVittseröd Stanstorpsgraven Per Pålssons gravVittseröd MemberLeafletsAffinities with Cycadeoidaceae inside Bennettitales. PterophyllumP. majus P. kochii P. aequale P. ptilum P. compressumVittseröd Stanstorpsgraven Per Pålssons gravVittseröd MemberLeafletsAffinities with Williamsoniaceae inside Bennettitales. In the uppermost layers is the dominant macroflora outside Pelmastermales RhizomopterisR. cruciataStanstorpsgraven Ormanäsgraven Kullans stenbrottStanstorp Member Vittseröd MemberIsolated pinnaeAffinities with Dipteridaceae inside Polypodiales. SagenopterisS. nilssoniana S. rhoifolia S. undulataVittseröd Stanstorpsgraven Per Pålssons grav Ormanäsgraven Kullans stenbrottStanstorp Member Vittseröd MemberIsolated pinnaeAffinities with Caytoniaceae inside Pteridospermatophyta. SchizolepisS. hörensisVittseröd Stanstorpsgraven Per Pålssons grav Ormanäsgraven Kullans stenbrottStanstorp Member Vittseröd MemberOvulate StrobiliAffinities with Schizolepisaceae inside Pinaceae. Associated with Pinaceae thanks to the presence of separated seen scales and bract scales.StachyotaxusS. septentrionalis S. elegansVittseröd Stanstorpsgraven Per Pålssons grav Ormanäsgraven Kullans stenbrottStanstorp Member Vittseröd MemberIsolated LeavesAffinities with Palissyaceae inside Palissyales. StenorachisS. dubiusVittseröd Stanstorpsgraven Per Pålssons grav Ormanäsgraven Kullans stenbrottStanstorp Member Vittseröd MemberReproductive OrgansAffinities with Czekanowskiales inside Ginkgoales.ThaumatopterisT. schenkii T. braunianaVittseröd Stanstorpsgraven Per Pålssons grav Ormanäsgraven Kullans stenbrottStanstorp Member Vittseröd MemberIsolated pinnaeAffinities with Dipteridaceae inside Polypodiales. ToditesT. goeppertianusStanstorpsgraven Ormanäsgraven Kullans stenbrottStanstorp MemberIsolated pinnaeAffinities with Osmundaceae inside Osmundales. WielandiellaW. punctata W. angustifoliaStanstorpsgravenStanstorp MemberFemale Bennetite "flower"Affinities with Williamsoniaceae inside Bennettitales. Wielandiella may be regarded as a fossil taxon characterized by bennettitalean shrubs with branched stems and a divaricate architecture
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