Gerdemann clay pit, Gronau (Cretaceous to of Germany)

Where: Nordrhein-Westfalen, Germany (52.3° N, 7.0° E: paleocoordinates 43.4° N, 15.6° E)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Bückeberg Formation, Middle Berriasian to Middle Berriasian (145.0 - 140.2 Ma)

• Early Cretaceous, latest Berriasian, upper Osterwald Succession, Bückeberg Formation aka "Wealden 6"

•Although "Berriasian ("Wealden") and middle Valanginian" shales were quarried, the reported specimen ages in Hampe (2013) are middle-late Berriasian

• bed-level stratigraphic resolution

Environment/lithology: estuary or bay; shale and claystone

• The occurrence of the monotypicmyoid clam Corbula indicates a brackish environment of the Osterwald Succession (Kemper 1976).
• "...an irregular fissured shale whose fissure surfaces are coloured very characteristically rustybrown and are full of compressed Cyrena [Cyrena is a synonym of the freshwater/estuarine bivalve Corbicula according to the bivalve Treatise]. This shaly bed is underlaid by a 3 cm thick sticky layer of clay which runs far into the outcrop. According to the master, the skeleton (of Brancasaurus) was found immediately above the clay bed in the lowest part of the irregularly fissured top layer of the schist" (Wegner 1914, from a translation).

Size classes: macrofossils, mesofossils

Collected by Presented by Herren Gerdemann and Bertelsmann (quarry owners) in 1910

Collection methods: quarrying, mechanical,

• GWWU, Geomuseum der Westfaelischen Wilhems-Universitaet, Münster, Germany collection

•At the beginning of the 20th century, the pit of the Gerdemann & Co. brickworks had a depth of 30–40 m that contained Berriasian (‘‘Wealden’’) and middle Valanginian shales (Schleicher 1995). The pit was closed in 1917, because of a water ingress (Thiermann 1968). During a period of water shortage in 1959 the pit was later dewatered but subsequently closed again (Kemper 1961).

Primary reference: S. Sachs. 1997. Erster Nachweis eines gepanzerten Dinosauriers (Reptilia, Ornithischia, Thyreophora) aus der Unterkreide (Berrias) von Gronau in Westfalen. Neues Jahrbuch für Geologie und Paläontologie Monatshefte 1997(1):56-64 [M. Carrano/M. Carrano/M. Carrano]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 45760: authorized by Matthew Carrano, entered by Matthew Carrano on 30.11.2004, edited by Roger Benson, Philip Mannion and Jonathan Tennant

Creative Commons license: CC BY (attribution)

Taxonomic list

Bivalvia
 Pholadida - Corbulidae
Corbula sp.1 Bruguière 1789 clam
 Cardiida - Cyrenidae
Cyrena sp.5 Lamarck clam
Gastropoda
 Sorbeoconcha - Cassiopidae
Glauconia sp.5 Stoliczka 1868 snail
Chondrichthyes
 Hybodontiformes - Hybodontidae
Hybodus sp.1 Agassiz 1837 elasmobranch
The fish fauna is represented by teeth of hybodont sharks (Hybodus, Egertonodus, Lonchidion, Lissodus) and of actinopterygian genera, such as the amiiform Caturus, the semionodontid Lepidotes, the pycnodontids Coelodus and Sphaerodus and the pholidophoriformes Ionoscopus and Callopterus (Kemper 1976; Nyhuis and Herbig 2009).
Egertonodus sp.1 Maisey 1987 elasmobranch
The fish fauna is represented by teeth of hybodont sharks (Hybodus, Egertonodus, Lonchidion, Lissodus) and of actinopterygian genera, such as the amiiform Caturus, the semionodontid Lepidotes, the pycnodontids Coelodus and Sphaerodus and the pholidophoriformes Ionoscopus and Callopterus (Kemper 1976; Nyhuis and Herbig 2009).
 Hybodontiformes - Lonchidiidae
Lonchidion sp.1 Estes 1964 elasmobranch
The fish fauna is represented by teeth of hybodont sharks (Hybodus, Egertonodus, Lonchidion, Lissodus) and of actinopterygian genera, such as the amiiform Caturus, the semionodontid Lepidotes, the pycnodontids Coelodus and Sphaerodus and the pholidophoriformes Ionoscopus and Callopterus (Kemper 1976; Nyhuis and Herbig 2009).
Lissodus sp.1 Brough 1935 elasmobranch
The fish fauna is represented by teeth of hybodont sharks (Hybodus, Egertonodus, Lonchidion, Lissodus) and of actinopterygian genera, such as the amiiform Caturus, the semionodontid Lepidotes, the pycnodontids Coelodus and Sphaerodus and the pholidophoriformes Ionoscopus and Callopterus (Kemper 1976; Nyhuis and Herbig 2009).
Actinopteri
 Pycnodontiformes - Pycnodontidae
Sphaerodus sp.1 Agassiz 1843
The fish fauna is represented by teeth of hybodont sharks (Hybodus, Egertonodus, Lonchidion, Lissodus) and of actinopterygian genera, such as the amiiform Caturus, the semionodontid Lepidotes, the pycnodontids Coelodus and Sphaerodus and the pholidophoriformes Ionoscopus and Callopterus (Kemper 1976; Nyhuis and Herbig 2009).
Coelodus sp.1 Haeckel
The fish fauna is represented by teeth of hybodont sharks (Hybodus, Egertonodus, Lonchidion, Lissodus) and of actinopterygian genera, such as the amiiform Caturus, the semionodontid Lepidotes, the pycnodontids Coelodus and Sphaerodus and the pholidophoriformes Ionoscopus and Callopterus (Kemper 1976; Nyhuis and Herbig 2009).
 Amiiformes -
Ionoscopus sp.1 Costa 1853 bowfin
The fish fauna is represented by teeth of hybodont sharks (Hybodus, Egertonodus, Lonchidion, Lissodus) and of actinopterygian genera, such as the amiiform Caturus, the semionodontid Lepidotes, the pycnodontids Coelodus and Sphaerodus and the pholidophoriformes Ionoscopus and Callopterus (Kemper 1976; Nyhuis and Herbig 2009).
 Amiiformes - Caturidae
Caturus sp.1 Agassiz 1843 bowfin
The fish fauna is represented by teeth of hybodont sharks (Hybodus, Egertonodus, Lonchidion, Lissodus) and of actinopterygian genera, such as the amiiform Caturus, the semionodontid Lepidotes, the pycnodontids Coelodus and Sphaerodus and the pholidophoriformes Ionoscopus and Callopterus (Kemper 1976; Nyhuis and Herbig 2009).
 Lepisosteiformes -
Lepidotes sp.1 Agassiz 1843 gar
The fish fauna is represented by teeth of hybodont sharks (Hybodus, Egertonodus, Lonchidion, Lissodus) and of actinopterygian genera, such as the amiiform Caturus, the semionodontid Lepidotes, the pycnodontids Coelodus and Sphaerodus and the pholidophoriformes Ionoscopus and Callopterus (Kemper 1976; Nyhuis and Herbig 2009).
 Ionoscopiformes - Furidae
Callopterus sp.1 Thollière 1854
The fish fauna is represented by teeth of hybodont sharks (Hybodus, Egertonodus, Lonchidion, Lissodus) and of actinopterygian genera, such as the amiiform Caturus, the semionodontid Lepidotes, the pycnodontids Coelodus and Sphaerodus and the pholidophoriformes Ionoscopus and Callopterus (Kemper 1976; Nyhuis and Herbig 2009).
Reptilia
 Testudines - Pleurosternidae
Desmemys bertelmanni n. gen. n. sp.5 turtle
(holotype)
Desmemys sp.3 Wegner 1911 turtle
 Theropoda -
 Ornithischia - Nodosauridae
Hylaeosaurus sp.4 Mantell 1833 ornithischian
 Loricata -
Crocodylia indet. crocodilian
A crocodilian tooth was identified early by the famous palaeontologist Eberhard Fraas (Landois 1904)
 Sauropterygia -
Plesiosauria sp.5 de Blainville 1835 plesiosaur
Plesiosauria indet.5 de Blainville 1835 plesiosaur
Hosius (1893) described a clavicula of the ornithopod dinosaur ‘‘Iguanodon’’ from the Gronau pit. However, this element belongs to the distal propodial part of a large plesiosaurid according to Wegner (1914).
Plesiosaurus degenhardti2 Koken 1887 plesiosaur
Vertebrae from the collection of an official of the local public health authority
"Plesiosaurus kanzleri n. sp." = Peloneustes kanzleri2 Koken 1905 plesiosaur
Dorsal vertebra
 Sauropterygia - Leptocleididae
"Plesiosaurus valdensis" = Hastanectes valdensis2, Brancasaurus brancai n. gen. n. sp.5
"Plesiosaurus valdensis" = Hastanectes valdensis2 Lydekker 1889 plesiosaur
Vertebrae from the collection of an official of the local public health authority
Brancasaurus brancai n. gen. n. sp.5 Wegner 1914 plesiosaur
GWWU A3.B4 (skeleton with skull) from the "subcretaceous fauna" level (mid-Berriasian)
 Sauropterygia - Elasmosauridae
Gronausaurus wegneri n. gen. n. sp.1
Gronausaurus wegneri n. gen. n. sp.1 Hampe 2013 elasmosaur
GWWU A3.B2, partial postcranial skeleton from "alpha", as the Berriasian-Valanginian boundary interval (latest Berriasian)
 Sauropterygia -
"Plesiosaurus limnophilus" = Cimoliosaurus limnophilus2
"Plesiosaurus limnophilus" = Cimoliosaurus limnophilus2 Koken 1887 plesiosaur
Vertebrae from the collection of an official of the local public health authority