# Hasle Formation

The Hasle Formation is a geologic formation on the island on Bornholm, Denmark. It is of early to late Pliensbachian age. Vertebrate fossils have been uncovered from this formation. The type section of the formation is found at the south of the costal Hasle Town, and it is composed by rusty yellow to brownish siltstones and very fine-grained sandstones. The southernmost arch, Hvjdoddebuen, is not as fossil-bearing as the type unit in Hasle. The formation can be separated in two different petrographic types: type 1 sandstones are friable with layers and lenses of concretionary siderite and type 2 well-cemented sandstones. Both types where deposited in a relatively high-energy marine environment with a diagenetic pattern that demonstrates a close relation to various phases of subsidence and uplift in the tectonically unstable Fennoscandian Border Zone. Most of its deposition happened on a storm-dominated shoreface, with the exposed parts deposited in an open marine shelf within 1–2 km distance from the fault-controlled coastlines. However, recent works have recovered terrestrial fauna from it, including a footprint, suggesting easterly winds and low tide could have exposed the inner parts of the upper shoreface, and create long-lasting Floodplain-type environments. Field works since 1984 have shown a mostly hummocky cross-stratified deposition, with great complexity of the sediments that suggests very complicated and variable flow conditions, with Megaripples derived from storm events. Storms were frequent and the coastline faced a wide epeiric sea with a fetch towards the west of possibly 1000 kilometers. The Jamesoni–Ibex Chronozone in the Central European Basin represents a clear sea Transgression, due to the appearance of ammonites from Thuringia and southern Lower Saxony, showing a full marine ingression towards the west. This rise in the sea level is also measured in the north, as is proven by the presence of Uptonia jamesoni in Kurremölla (Röddinge Formation, Skåne) and Beaniceras centaurus plus Phricodoceras taylori on the Hasle Formation. The whole Hasle Sandstones are a result of this rise in the sea level, where the marine sediments cover the deltaic layers of the Rønne Formation. The rise in the sea level is observed on palynology, as on the Hasle Formation Nannoceratopsis senex (Dinoflajellate) and Mendicodinium reticulaturn (Algae Acritarch) appear, indicating a transition from paralic and restricted marine to fully marine.

## Fossil content
### Annelida

| Genus | Species | Location | Material | Notes | Images |
| Serpula? | S.? alicecooperi | Stampeå stream | One well-preserved tube and several fragmentary tubes | A sessile, marine annelid tube worm of the family Serpulidae. | Head of a modern Serpula vermicularis |
| Pentaditrupa | P. quinquesulcata | Stampeå stream | Two tubes | A sessile, marine annelid tube worm of the family Serpulidae | |

### Brachiopoda

| Genus | Species | Location | Material | Notes | Images |
| Rhynchonella | R. jurensis R. variabilis | Stampeå stream South of Hasle | Shells | A saltwater Brachiopodan, member of Rhynchonellata inside Rhynchonellida. Found associated with Plicatula on long-term well-oxygenated conditions within the substrate and bottom waters. | |
| Waldheimia | W. sp. | Stampeå stream | Shells | A Saltwater lamp shell Brachiopodan, member of Terebratulidae inside Terebratulida. The specimens are rather incomplete. The genus is a possible junior synonym of Terebratula. | |

### Bivalvia

| Genus | Species | Location | Material | Notes |
| Astarte | A. obsoleta A. sp. | Stampeå stream South of Hasle | Shells | A saltwater Clam, type member of the family Astartidae inside Carditida. It is found on small, smooth Clam associations, with the exception of one does section, with less well-preserved stone cores and imprints. |
| Avicula | A. inaequivalvis A. sp. | Stampeå stream South of Hasle | Shells | A saltwater pearl oyster, member of the family Pteriidae inside Ostreida. Some specimens are big and found associated with Burrow-filled surfaces. This well-known species occurs extremely frequently; Copies occur at all ages, as well as right-handers Left shells have been found. |
| Cardinia | C. multicostatum C. crassiuscula C. infera | Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | A saltwater Clam, type member of the family Cardiidae inside Carditida. Is a frequently occurring Clam. |
| Cucullaea | C. sp. | South of Hasle | Shells | A saltwater Clam, type member of the family Cucullaeidae inside Arcida. |
| Cyprina | C. cardioides | Stampeå stream Hvideoddebuen Nebbeodde | Shells | A saltwater Clam, member of the family Arcticidae inside Veneroidei. Is a frequently occurring Clam. |
| Cypricardia | C. cf.laevigata C. cf.tetragona | South of Hasle | Shells | A saltwater Clam, member of the family Trapezidae inside Veneroidei. |
| Dendostrea | D. sandvichensis | Stampeå stream | Shells | A saltwater Oyster, member of the family Ostreinae inside Ostreida. Identified originally as Ostrea semiplicata |
| Gervilleia | G. sjögreni G. cf. hagenovii G. sp. | Stampeå stream South of Hasle | Shells | A saltwater Oyster, member of the family Bakevelliidae inside Ostreida. Found on a series of incomplete Stone Cores filled with specimens, that by Size and Form can be possibly attributable to Gervilleia aerosa. |
| Hinnites | H. tumidus | Stampeå stream | Shells | A saltwater Scallop, member of the family Pectinoidae inside Pectinida. A Pair of incomplete specimens of a Hinnites are known and probably match with the species Hinnites tumidus; however, the state of preservation is bad, with the assignment rather uncertain. |
| Lima | L. succincta | Stampeå stream | Shells | A saltwater file Clam, type member of the family Limidae inside Pectinida. |
| Limea | L. acuticosfa | Stampeå stream | Shells | A saltwater file Clam, member of the family Limidae inside Pectinida. Mostly know due to a single young individual. |
| Luciniola | L. pumila | Stampeå stream | Shells | A saltwater Clam, type member of the family Lucinidae inside Lucinida. |
| Modiolus | M. scalprum M. sp. | South of Hasle | Shells | A saltwater Mussel, type member of the family Mytilidae inside Mytilida. |
| Myoconcha | M. stampensis M. jespersenii | Stampeå stream | Shells | A saltwater Clam, member of the family Kalenteridae inside Cardiida. One of the most frequent and characteristic Fossils in the formation |
| Mytilus | M. sp. | South of Hasle | Shells | A saltwater Mussel, type member of the family Mytilidae inside Mytilida. |
| Nucula | N. distinguenda N. (Leda?) dr. omaliusi? N. pinguis | Stampeå stream | Shells | A saltwater nut Clam, type member of the family Nuculidae inside Nuculida. Two copies of a Nucula (leda?) so closely in accordance with Moberg's depictions and description of occurring at Kurremolla. |
| Nuculana | N. bornholmiensis N. subovalis N. complanata | Stampeå stream | Shells | A saltwater pointed nut Clam, type member of the family Nuculanidae inside Nuculida. Nuculana bornholmiensis is a very common genus only found locally. |
| Palaeoneilo | P. bornholmiensis P. sp. | Stampeå stream South of Hasle | Shells | A saltwater pointed nut Clam, type member of the family Nuculanidae inside Nuculida. |
| Parallelodon | P. cypriniformis P. pullus | Stampeå stream South of Hasle | Shells | A saltwater Clam, type member of the family Parallelodontidae inside Arcida. This species occurs frequently and varies a lot |
| Pecten | P. priscus P. aequivalvis | Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | A saltwater Scallop, type member of the family Pectinoidae inside Pectinida. This species has been exceedingly frequent, and numerous Fragments are available. |
| Perna | P. sp. | South of Hasle | Shells | A saltwater Mussel, member of the family Mytilidae inside Mytilida. |
| Pleuromya | P. forchhammeri P. dunkeri | Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | A saltwater Clam, type member of the family Pleuromyidae inside Pholadida. Three specimens of this species have been found. |
| Plicatula | P. spinosa | Stampeå stream | Shells | A saltwater Scallop, type member of the family Plicatulidae inside Pectinida. Two poorly preserved specimens have been found. |
| Spondylus | S. sp. | South of Hasle | Shells | A saltwater Scallop, member of the family Pectinoidae inside Pectinida. |
| Tancredia | T. lineata T. elegans T. tenera T. johnstrupi | Stampeå stream South of Hasle | Shells | A saltwater Clam, type member of the family Tancrediidae inside Carditida. Tancredia lineata Is based on six shell cores, of which one complete, the others a little defective at the front end. |
| Tellina | T. sp. | South of Hasle | Shells | A saltwater tellin Clam, member of the family Tellinidae inside Cardiida. |

### Scaphopoda

| Genus | Species | Location | Material | Notes | Images |
| Laevidentalium | L. etalense L. elongatum L. sp. | Stampeå stream South of Hasle | Shells | A saltwater tusk shell (Scaphopoda), member of the family Dentaliidae inside Dentaliida | |

### Gastropoda

| Genus | Species | Location | Material | Notes |
| Actaeonina | A. nathorsti | Stampeå stream South of Hasle | Shells | A saltwater Snail, type member of the family Acteoninidae inside Prosobranchia. Of this small species there are quite a few specimens, both stone cores and imprints that perfectly allow identifying the species. |
| Amberlya | A. sp. | South of Hasle | Shells | A saltwater Snail, type member of the family Spirostylidae inside Murchisoniina. |
| Chemnitzia | C.? undulata C. craticia C. citharella C. blainvillei | Stampeå stream | Shells | A saltwater Snail, member of the family Pyramidellidae inside Pyramidelloidea. Two Specimens of a Turritella-like Gastropod found locally have been refer to the Genus. Chemnitzia citharella includes ten specimens, the largest of the genus found locally. However, most of the specimens are shell cores. |
| Eucyclus | E. sp. | Stampeå stream | Shells | A saltwater Snail, type member of the family Eucyclidae inside Seguenzioidea. The material available is rather poor. |
| Margarites | M. solarium | Stampeå stream | Shells | A saltwater Snail, member of the family Turbinidae inside Turbinoidea. Occurs frequently, especially on marine ingression surfaces. |
| Natica | N. sp. | South of Hasle | Shells | A saltwater moon Snail, type member of the family Naticidae inside Naticoidea. |
| Neritina | N. cf.liasina | South of Hasle | Shells | A saltwater Snail, type member of the family Neritidae inside Neritoidea. |
| Pleurotomaria | P. expansa P. sp. | Stampeå stream South of Hasle | Shells | A saltwater Snail, type member of the family Pleurotomariidae inside Pleurotomarioidea. |
| Trochus | T. laevis T. subsulcatus | Stampeå stream | Shells | A saltwater top Snail, type member of the family Trochidae inside Trochoidea. Rare compared with other species found locally. |

### Belemnites

| Genus | Species | Location | Material | Notes | Images |
| Nannobelus | N. acutus | Stampeå stream South of Hasle | Phragmocones | A belemnite, incertae sedis member of the family Belemnitida. Frequently shows the embryonic chamber preserved as a bladder, slightly bent forward-towards the ventral side. | |
| Subhastites | S. paxillosus S. sp. | Stampeå stream | Phragmocones | A Belemnite, member of the family Hastitidae inside Belemnitida. | |

### Ammonites

| Genus | Species | Location | Material | Notes |
| Acanthopleuroceras? | A.? sp. indet. | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | A possible Ammonite of the family Polymorphitidae inside Ammonitida. |
| Aegoceras | A. armatum | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Liparoceratidae inside Ammonitida. Later renamed Beaniceras centaurus, senior synonym of Aegoceras centaurus |
| Aegoceras | A. centaurus | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Liparoceratidae inside Ammonitida. Later renamed Beaniceras centaurus, senior synonym of Aegoceras centaurus |
| Aegoceras | A. capraius | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Liparoceratidae inside Ammonitida. Later renamed Beaniceras centaurus, senior synonym of Aegoceras centaurus |
| Aegoceras | A. mangenesti | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Liparoceratidae inside Ammonitida. Later renamed Beaniceras centaurus, senior synonym of Aegoceras centaurus |
| Aegoceras | A. pettos | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | Junior synonym of Coeloceras pettos, possible synonym of Coeloceras grenouillouxi |
| Apoderoceras | A. aculeatum | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Polymorphitidae inside Ammonitida. |
| Arnioceras | A. falcaries | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Arietitidae inside Ammonitida. |
| Beaniceras | B. centaurus | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Liparoceratidae inside Ammonitida. Senior synonym of Aegoceras centaurus |
| Coeloceras | C. pettos | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Coeloceratidae inside Psilocerataceae. Senior synonym of Aegoceras pettos. Possible junior synonym of Coeloceras grenouillouxi |
| Coeloceras | C. grenouillouxi | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | Possible senior synonym of Coeloceras pettos |
| Paramicroderoceras | P. fila | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Juraphyllitidae inside Phylloceratina. |
| Paramicroderoceras | P.? sp indet | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Juraphyllitidae inside Phylloceratina. |
| Phylloceras | P. loscombii | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Juraphyllitidae inside Phylloceratina. |
| Phricodoceras | P. taylori | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Phricodoceratidae inside Psilocerataceae. |
| Platypleuroceras | P. brevispina | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Polymorphitidae inside Ammonitida. |
| Platypleuroceras | P. submulticum | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Polymorphitidae inside Ammonitida. |
| Platypleuroceras | P. caprarium | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Polymorphitidae inside Ammonitida. |
| Platypleuroceras | P. spp. indet | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Polymorphitidae inside Ammonitida. |
| Radstockiceras | R. hechingense | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Oxynoticeratidae inside Psilocerataceae. |
| Tragophylloceras | T. numismale | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Juraphyllitidae inside Phylloceratina. |
| Tragophylloceras | T. sp | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Juraphyllitidae inside Phylloceratina. |
| Uptonia | U. lata | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Polymorphitidae inside Ammonitida. |
| Uptonia | U. sp indet | Rønne Lervarefabrik Stampeå stream South of Hasle Hvideoddebuen Nebbeodde | Shells | An Ammonite of the family Polymorphitidae inside Ammonitida. |

### Crustacea

| Genus | Species | Location | Material | Notes | Images |
| Goniodromites? | G.? liasicus | Stampeå stream | 2 partially preserved specimens | A possible early Brachyuran, then recovered as not related with Goniodromites, and suggested to be from younger strata, what was contested latter. | |

### Chondrichthyes

Unidentified fin spines are known from this formation.
| Genus | Species | Location | Material | Notes |
| Acrodus | A. minimus | Stampeå stream | Large number of teeth | A marine shark, member of the family Acrodontidae inside Hybodontiformes. |
| Agaleus | A. dorsetensis | Hasle Harbour | Four teeth | A marine shark, type member of the family Agaleidae inside Euselachii. This genus may have been a suction feeder as its anterior teeth are similar to those of extant nurse sharks. |
| Hybodontidae | Indeterminate | Hasle Harbour | One incomplete spine | A marine shark, incertae sedis inside Hybodontiformes. |
| Hybodus | H. reticulatus | Hasle Harbour | 21 incomplete crowns | A marine shark, type member of the family Hybodontidae inside Hybodontiformes. |
| Hybodus | H. delabechei | Hasle Harbour | Three complete crowns | A marine shark, type member of the family Hybodontidae inside Hybodontiformes. Its teeth suggest that it may have been feeding on shelly invertebrates. |
| Lissodus | L. hasleensis | Hasle Harbour | Four complete teeth | A marine/brackish shark, member of the family Lonchidiidae inside Hybodontiformes. |
| Myriacanthidae | Indeterminate | Hasle Harbour | Tooth plates | Indeterminate tooth plates of marine chimaeras. |
| Myriacanthus | M. paradoxus | Cliff section 100 m south of Hasle | Tooth plates | A marine chimaera. |
| Myriacanthus | M. sp. | Hasle Harbour | Isolated tooth plate | A marine Chimaera, type member of the family Myriacanthidae inside Chimaeriformes. |
| Oblidens | O. bornholmensis | Cliff section 100 m south of Hasle | Multiple tooth plates. | A marine Chimaera, member of the family Myriacanthidae inside Chimaeriformes. |
| Paraorthacodus | P. sp | Hasle Harbour | Two incomplete teeth | A marine shark, member of the family Palaeospinacidae inside Synechodontiformes. |
| Synechodus | S. occultidens | Hasle Harbour | Four incomplete teeth | A marine shark, type member of the family Palaeospinacidae inside Synechodontiformes. |

### Actinopteri

| Genus | Species | Stratigraphic position | Material | Notes | Images |
| Archaeotolithus | A. bornholmiensis A. sp. | Stampeå stream | Otoliths | Interpreted as sagittal otoliths of a Palaeonisciformes Indet. Fish Otoliths, originally assigned to the extant family Sciaenidae, then from members of Palaeoniscidae and some other research suggest affinities with Pholidophoriformes. | |
| Saurichthys? | S. acuminata? S. longidens? | Stampeå stream | Teeth | A marine/brackish Osteichthyes, representative of the family Saurichthyidae inside Chondrostei. The referral to the genus must be taken with caution, as currently it´s geological range is limited to the Triassic. | Saurichthys model |

### Sauropterygia

| Genus | Species | Location | Material | Notes | Images |
| Plesiosauria | Indeterminate | Stampeå stream Hasle Harbour | Complete right ischium Complete isolated humerus Complete ulna/fibula Isolated flattened lunate epipodial bone Fragment of jaw Sacral Vertebra Sacral Rib Single Fragment of Rib | Indeterminate Plesiosauroidea Material | |
| Plesiosauroidea | Indeterminate | Hasle Harbour | Tooth | Indeterminate Plesiosauroidea Material | |
| Pliosauroidea | Indeterminate | Hasle Harbour | Fourteen isolated teeth | A marine plesiosaur, member of the family Pliosauroidea inside Sauropterygia. Resembles Attenborosaurus. | |
| Rhomaleosauridae | Indeterminate | Hasle Harbour | Tooth | A marine plesiosaur, member of the family Rhomaleosauridae inside Sauropterygia. Resembles Rhomaleosaurus. | Rhomaleosaurus |

### Thalattosuchia

| Genus | Species | Location | Material | Notes | Images |
| Teleosauridae | Indeterminate | Hasle Harbour | DK-1072, a dermal plate | A Teleosauridae Thalattosuchian. One of the northernmost fossil finds of the group and one of the few of the pliensbachian worldwide, it represents a genus whose dermal armor was similar to the genus Macrospondylus of the Toarcian. | Macrospondylus example of Teleosauroid |

### Pterosauria

| Genus | Species | Location | Material | Notes | Images |
| Pterosauria? | Indeterminate | Hasle Harbour | Uncertain Remains | A possible Pterosaur. Is quoted the find of a "Flying Reptile" on the Hasle Sandstone by C. Malling at the beginning of the 20th century. No further data related to the find has been published. | Example of coeval Pterosaur, Dimorphodon |

### Theropods

| Genus | Species | Location | Material | Notes | Images |
| Neotheropoda | Indeterminate | Hasle Harbour | Propodial bone, possibly a radius | Theropod, incertae sedis inside Neotheropoda. Extremely hollow shaft suggests that it most likely belonged to a juvenile member of a theropod dinosaur. | Segisaurus a coeval North American genus |
| Stenonyx | S. isp. | Hasle Harbour | MGUH – 30889, single Footprint | Theropod Tracks, member of the ichnofamily Anchisauripodidae, incertae sedis inside Theropoda. Considered a very Small Dinosaur, probably a juvenile. The Foot resembles those of young Coelophysis from Ghost Ranch Quarries. Stenonyx footprints had been described from the Early Jurassic Soltykow (Hettangian) and an identical one from Szydlowek (Pliensbachian), linking southern Sweden, Bornholm and Poland, contiguous during the Early Jurassic and dinosaurs could thus freely roam this large area. | |
| Theropoda | Indeterminate | Hasle Harbour | Isolated Teeth | Theropod, incertae sedis | |

### Sauropodomorpha

| Genus | Species | Location | Material | Notes | Images |
| Massopoda | Indeterminate | Hasle Harbour | DK966, metatarsal, metapodial or a propodial bone | A Sauropodomorph of uncertain placement, probably a rather basal genus. | Mussaurus, a possible relative of DK966 |
| Sauropoda | Indeterminate | Hasle Harbour | DK976, spinous process from a cervical vertebrae | A Sauropod Sauropodomorph. Assigned to an early actual Sauropods, which also have quite powerful lateral processes and whose cervical vertebrae are relatively long. | |
| Turiasauria | Indeterminate | Hasle Harbour | NHMD 1185136, Isolated tooth | A possible Turiasaurian Eusauropod. The oldest geological record of the family, likely represents a new unnamed taxon, estimated to have been 10–14 m long based on related taxa. | Turiasaur tooth NHMD 1185136 from the Hasle Formation |

### Synapsida

| Genus | Species | Location | Material | Notes | Images |
| Tritylodontidae | Indeterminate | Hasle Harbour | NHMD 1725979: an isolated tooth crown | A Tritylodontoidea Cynognathian. Hasle Formation fossil cannot be confidently placed within any known genus, it can be either a primitive Tritylodont related to specimens that lack post-canines (Yunnanodon, Dianzhongia), or an early derived genus of the Stereognathus group. It is the oldest occurrence of a mammaliamorph in Scandinavia. | Bienotherium, a coeval genus |