View source for Knoetschkesuchus

{{Short description|Extinct genus of reptiles}}
{{good article}}
{{Italic title}}
{{Automatic taxobox
| name = ''Knoetschkesuchus''
| fossil_range = {{fossilrange|Kimmeridgian}}
| image = Knoetschke-3a.png
| image_caption = Type specimen of ''Knoetschkesuchus langenbergensis''
| display_parents= 2
| taxon = Knoetschkesuchus
| authority = Schwarz ''et al.'', 2017
| type_species = '''''Knoetschkesuchus langenbergensis'''''
| type_species_authority = Schwarz ''et al.'', 2017
| subdivision_ranks = [[Species]]
| subdivision = 
* '''''K. langenbergensis''''' <small>Schwarz ''et al.'', 2017 (type)</small>
* '''''K. guimarotae''''' <small>(Schwarz & Salisbury, 2005) (originally ''[[Theriosuchus]] guimarotae'')</small>
}}

'''''Knoetschkesuchus''''' is a genus of small [[atoposauridae|atoposaurid]] [[crocodylomorpha|crocodylomorph]] from the [[Late Jurassic]] of [[Germany]] and [[Portugal]]. Two species are known: the German species '''''K. langenbergensis''''', described by Schwarz and colleagues in 2017 based on two partial skeletons and various isolated bones; and the Portuguese species '''''K. guimarotae''''', named from over 400 specimens including several partial skeletons. ''Knoetschkesuchus'' was a small and short-snouted crocodilian, measuring about {{convert|55|cm}} in length, that primarily fed on small prey, including [[invertebrate]]s, [[amphibian]]s, and [[mammal]]s. This specialization towards small prey ecologically separated ''Knoetschkesuchus'' from most of the other diverse crocodilians that it lived with in the island ecosystem of Jurassic [[Europe]].

Both species were formerly recognized as belonging to ''[[Theriosuchus]]''; ''K. guimarotae'' was initially named as ''T. guimarotae'', and specimens of ''K. langenbergensis'' were initially referred to ''T. pusillus'' upon their discovery. Schwarz and colleagues recognized a number of characteristics that united these two taxa to the exclusion of other species of ''Theriosuchus''; in particular, ''Knoetschkesuchus'' only has two distinct types of teeth, lacking the leaf-shaped teeth seen in other atoposaurids. Other distinguishing traits include the relatively wide skull, and the presence of the [[antorbital fenestra|antorbital]] and mandibular fenestrae in all life stages.

==Discovery and naming==
===''K. langenbergensis''===
[[File:Knoetschke-2.png|thumb|Location of Bed 83, the discovery site of ''K. langenbergensis'', in the "Mittleres Kimmeridge"]]
The material of the type species of ''Knoetschkesuchus'', ''K. langenbergensis'', comes from a [[marl]]y [[limestone]] bed (numbered as Bed 83, not Bed 93 as reported by some publications) containing [[recrystallization (chemistry)|recrystallized]] [[micrite|micritic]] [[intraclasts]], located within the Langenberg Quarry in the [[Harz|Harz Mountains]] near [[Goslar]], [[Lower Saxony]], [[Germany]]. These deposits have been dated to the Upper [[Kimmeridgian]] stage of the [[Jurassic]]—specifically, to the regional equivalent of the Upper Kimmeridgian known as the Mittleres Kimmeridge,<ref name="tracks">{{cite journal | last1 = Lallensack | first1 = J. | last2 = Sander | first2 = P.M. | last3 = Knötschke | first3 = N. | last4 = Wings | first4 = O. | title = Dinosaur tracks from the Langenberg Quarry (Late Jurassic, Germany) reconstructed with historical photogrammetry: Evidence for large theropods soon after insular dwarfism | issue = 18.2.31A | pages = 1–34 | date = 2015 | journal = Palaeontologia Electronica| volume = 18 | doi = 10.26879/529 | doi-access = free }}</ref> and belong to the [[Süntel Formation]].<ref name="geog">{{cite book | last1 = Pieńkowski | first1 = G. | last2 = Schudack | first2 = M.E. | last3 = Bosák | first3 = P. | last4 = Enay | first4 = R. | last5 = Feldman-Olszewska | first5 = A. | last6 = Golonka | first6 = J. | last7 = Gutowski | first7 = J. | last8 = Herngreen | first8 = G.F.W. | last9 = Jordan | first9 = P. | last10 = Krobicki | first10 = M. | last11 = Lathuiliere | first11 = B. | last12 = Leinfelder | first12 = R.R. | last13 = Michalik | first13 = J. | last14 = Monnig | first14 = E. | last15 = Noe-Nygaard | first15 = N. | last16 = Palfy | first16 = J. | last17 = Pint | first17 = A. | last18 = Rasser | first18 = M.W. | last19 = Reisdorf | first19 = A.G. | last20 = Schmid | first20 = D.U. | last21 = Schweigert | first21 = G. | last22 = Surlyk | first22 = F. | last23 = Wetzel | first23 = A. | last24 = Wong | first24 = T.E. | title = The Geology of Central Europe Volume 2: Mesozoic and Cenozoic | editor-last1 = McCann | editor-first1 = T. | date = 2008 | chapter = Jurassic | pages = 823–922 | publisher = Geological Society | location = London | url = http://geoscienceworld.org/content/the-geology-of-central-europe-volume-2 | chapter-url = https://www.researchgate.net/publication/260000209}}</ref> Although well-preserved, fossils from this quarry were recovered generally by regular blasting operations in the quarry.<ref name="desc"/>

Specimens belonging to ''Knoetschkesuchus'' are stored at the [[:de:Dinosaurier-Park Münchehagen|Dinosaurier-Freilichtmuseum Münchehagen]] (hereafter denoted by DFMMh/FV) in [[Rehburg-Loccum]], Germany. They are: the [[type (biology)|type]] specimen DFMMh/FV 200, the partial skeleton of an adult with a skull; DFMMh/FV 605, the complete skull of a juvenile; DFMMh/FV 261, an isolated [[angular bone|angular]]; DFMMh/FV 790.12, an isolated left [[mandible|dentary]]; DFMMh/FV 279, an isolated [[femur]]; DFMMh/FV 790.11, an isolated [[metatarsal bones|metatarsal]]; and DFMMh/FV 325, a partial skeleton including [[osteoderm]]s, vertebrae, and ribs. [[Stereo microscope|Stereomicroscopy]] was used to examine the specimens, which were described in a 2017 paper published by Daniela Schwarz, Maik Raddatz, and Oliver Wings.<ref name="desc"/>

The genus name ''Knoetschkesuchus'' combines the family name of Nils Knötschke, a researcher at the DFMMh who was responsible for the collection, curation, and preparation of Langenberg Quarry specimens, with the common crocodilian suffix ''suchus'', from the Greek ''souchos'' ("crocodile"). Meanwhile, the species name ''langenbergensis'' is in reference to the provenance of this species from the Langenberg Quarry.<ref name="desc"/>

===''K. guimarotae''===
Schwarz ''[[wikt:et al.|et al.]]'' also assigned an additional species to ''Knoetschkesuchus'', ''K. guimarotae'', which was originally classified as a species of ''[[Theriosuchus]]''. As reflected by the specific name, ''K. guimarotae'' originates from the [[lignite]] layers of the Guimarota quarry, located near [[Leiria]], [[Portugal]]. There are two primary vertebrate-bearing lignite strata within the so-called Guimarota-strata, which are separated by marly limestone and respectively known as the "Fundschichten" and "Ruafolge" subunits; ''K. guimarotae'' is known from both of these layers. They have been assigned to the [[Alcobaça Formation]], a subunit of the [[Abadia Formation]],<ref name="schudack1">{{cite book | last1 = Schudack | first1 = M.E. | pages = 21–26 | date = 2000 | chapter = Geological setting and dating of the Guimarota beds | title = Guimarota – A Jurassic Ecosystem | editor-last1 = Martin | editor-first1 = T. | editor-last2 = Krebs | editor-first2 = B. | chapter-url = http://www.pfeil-verlag.de/07pala/e2_80.html | isbn = 9783931516802 | publisher = Verlag Dr. Friedrich Pfeil | location = München}}</ref> which has been dated to the Kimmeridgian on the basis of fossil [[ostracod]]s.<ref name="guimarot">{{cite journal | last1 = Schwarz | first1 = D. | last2 = Salisbury | first2 = S.W. | title = A new species of ''Theriosuchus'' (Atoposauridae, Crocodylomorpha) from the Late Jurassic (Kimmeridgian) of Guimarota, Portugal | journal = Geobios | volume = 38 | issue = 6 | date = 2005 | pages = 779–802 | doi = 10.1016/j.geobios.2004.04.005 }}</ref><ref name="kimmerguima">{{cite journal | last1 = Sousa | first1 = L. | title = Upper Jurassic (Upper Oxfordian–Tithonian) palynostratigraphy from the Lusitanian Basin (Portugal) | pages = 49–77 | date = 1998 | journal = Memórias da Academia das Ciencias de Lisboa | volume = 37 | url = https://www.researchgate.net/publication/322530040 }}</ref><ref name="schudack2">{{cite book | last1 = Schudack | first1 = M.E. | pages = 33–36 | date = 2000 | chapter = Ostracodes and charophytes from the Guimarota beds | title = Guimarota – A Jurassic Ecosystem | editor-last1 = Martin | editor-first1 = T. | editor-last2 = Krebs | editor-first2 = B. | chapter-url = http://www.pfeil-verlag.de/07pala/e2_80.html | isbn = 9783931516802 | publisher = Verlag Dr. Friedrich Pfeil | location = München}}</ref>

The remains of ''K. guimarotae'' are stored at the Institute of Geological Sciences of the [[Free University of Berlin]] (hereafter IPFUB). Alongside the type specimen IPFUB Gui Croc 7308—which consists of a partial skull with jaws, a vertebra from the [[sacrum]], and two osteoderms—over 400 additional specimens are known, most of them consisting of single isolated bones. Among these, the more complete specimens are IPFUB Gui Gui Croc 7352 (tail vertebrae, femur, osteoderms); 7441 (osteoderms and [[ulna]]); 7545 ([[thoracic vertebrae|dorsal vertebrae]], [[ischium|ischia]], osteoderms); 7564 (femur, [[humerus]], osteoderms); 7634 (dorsal vertebrae, rib, osteoderms); and 8037 ([[cervical vertebrae|cervical]] and dorsal vertebrae, and osteoderms). More specimens are known, but they remain unprepared. Some specimens show the marks of scavenging.<ref name="guimarot"/>

==Description==
[[File:Knoetschkesuchus2.jpg|left|thumb|Life restoration of ''K. langenbergensis'']]
As with other members of the [[Atoposauridae]],<ref name="desc"/> ''Knoetschkesuchus'' is very small, with ''K. guimarotae'' measuring only {{convert|55|cm}} long at maximum.<ref name="guimarot"/> Typical of the group, both species were [[quadrupedalism|quadrupedal]], bearing long and slender limbs.<ref name="phylo">{{cite journal | last1 = Buscaloni | first1 = A.D. | last2 = Sanz | first2 = J.L. | title = Phylogenetic relationships of the Atoposauridae (Archosauria, Crocodylomorpha) | journal = Historical Biology | volume = 1 | issue = 3 | doi = 10.1080/08912968809386477 | pages = 233–250 | date = 1988 | doi-access = free }}</ref> The backs of both of the known species are covered with two rows of bony rectangular osteoderms, centred at the midline, that are wider than they are long.<ref name="desc">{{cite journal | last1 = Schwarz | first1 = D. | last2 = Raddatz | first2 = M. | last3 = Wings | first3 = O. | title = ''Knoetschkesuchus langenbergensis'' gen. nov. sp. nov., a new atoposaurid crocodyliform from the Upper Jurassic Langenberg Quarry (Lower Saxony, northwestern Germany), and its relationships to ''Theriosuchus'' | journal = PLOS ONE | volume = 12 | issue = 2 | page = e0160617 | doi = 10.1371/journal.pone.0160617 | pmid = 28199316 | pmc = 5310792 | date = 2017 | bibcode = 2017PLoSO..1260617S | doi-access = free }}</ref> Each osteoderm bears a keel running longitudinally, although the keels are less-developed in ''K. langenbergensis''.<ref name="desc"/> In at least ''K. guimarotae'', the osteoderms on the tail have sharper and higher keels; the ones near the back of the tail tend to be longer than they are wide, unlike the other osteoderms, and are also vaulted. The [[vertebra]]e of ''K. guimarotae'' are additionally [[vertebral column#variations in vertebrae|amphicoelous]], or concave at both ends;<ref name="guimarot"/> while initially proposed as a unique trait, ''Theriosuchus pusillus'' bears amphicoelous vertebrae as well.<ref name="desc"/><ref name="pusilvert">{{cite book | last1 = Salisbury | first1 = S.W. | last2 = Frey | first2 = E. | chapter = A biomechanical transformation model for the evolution of semi-spheroidal articulations between adjoining vertebral bodies in crocodilians | date = 2001 | title = Crocodilian Biology and Evolution | location = Chipping Norton | publisher = Surry Beatty & Sons | pages = 85–134 | editor-last1 = Grigg | editor-first1 = G.C. | editor-last2 = Seebacher | editor-first2 = F. | editor-last3 = Franklin | editor-first3 = C.E. | chapter-url = https://www.researchgate.net/publication/235949483 | url = https://books.google.com/books?id=Gf9qQgAACAAJ| isbn = 9780949324894 }}</ref> The skull and jaws, which exhibit a number of characteristics that separate ''Knoetschkesuchus'' from other atoposaurids, are described in further detail below.

===Snout===
[[File:Knoetschke-7.png|thumb|Reconstructed skulls of the type (A-B) and juvenile (C-D) specimens of ''K. langenbergensis'']]
The skull of ''Knoetschesuchus'' is relatively short, with the snout taking up 47% of skull length in ''K. langenbergensis'' and 42% in ''K. guimarotae'',<ref name="guimarot"/> which allows them to be classified as brevirostrine crocodilians.<ref name="rostrum">{{cite book | last1 = Busbey | first1 = A.B. | title = Functional Morphology in Vertebrate Paleontology | editor-last1 = Thomason | editor-first1 = J.J. | pages = 173–192 | url = http://www.cambridge.org/us/academic/subjects/earth-and-environmental-science/palaeontology-and-life-history/functional-morphology-vertebrate-paleontology?format=PB&isbn=9780521629218 | isbn = 9780521629218 | date = 1997 | publisher = Cambridge University Press | location = Cambridge | chapter = Structural consequences of skull flattening in crocodilians | chapter-url = https://www.researchgate.net/publication/261025947}}</ref> Along the side of the snout are two undulations, a smaller one on the [[premaxilla]] and a larger and broader one on the [[maxilla]]. The jagged [[suture (anatomy)|suture]] between the premaxilla and maxilla is angled towards the front of the skull in ''K. langenbergensis'' and towards the back in ''K. guimarotae''.<ref name="guimarot"/> Along the midline of the snout are the thin and wedge-like [[nasal bone|nasal]]s; the nostrils, which face upwards, are clearly separated by the nasals in ''K. guimarotae'',<ref name="guimarot"/> but it is not clear that this is the case in ''K. langenbergensis''.<ref name="desc"/>

At the back, the nasals are separated by the [[frontal bone|frontal]] in ''K. langenbergensis'', the back third of which is somewhat vaulted. The portion of the frontal between the eyes is one-third the width of the entire skull in both species, but it widens further back to form the front of the skull roof. The [[prefrontal bone|prefrontal]] is straight along its contact with the frontal and nasal (about half of the bone is in contact with each), but forms an angle between the margin of the eye socket and the lacrimal on the other side. This angle is rounded in ''K. guimarotae'' such that the bone is oval-shaped,<ref name="guimarot"/> but very pointed in ''K. langenbergensis'' such that the bone is triangular.<ref name="desc"/>

===Eye socket and skull roof===
The main body of the lacrimal is a rounded square with both faces of the bone are concave. Its contact with the nasal is rather limited in both species. The oval-shaped [[antorbital fenestra]] is small, being only 9% the length of the eye socket; its presence is unique to both species of the genus among atoposaurids. Meanwhile, the eye socket is large and oval, being 54% longer than it is tall. The drop-shaped [[palpebral bone|palpebrals]] project out from the tops of the eye sockets. In both species, the back two-thirds of the inner surface of the palpebral is slightly concave. Both species have a [[squamosal bone|squamosal]] in which the back third is bevelled; in ''K. langenbergensis'', the outer margin is somewhat convex.<ref name="desc"/>
[[File:Knoetschke-5.png|thumb|left|Photographs, interpretive drawings, and CT scans of the juvenile skull of ''K. langenbergensis'']]

Viewed from the top, the [[parietal bone|parietal]] increases in width at the back; the increase is small in ''K. langenbergensis'', such that the bone is overall rectangular, but the difference is larger in ''K. guimarotae''. The back of the bone bears a small notch in ''K. langenbergensis'' and a general concavity in ''K. guimarotae'' that slightly exposes the underlying [[occipital bone|supraoccipital]].<ref name="guimarot"/> The [[postorbital bone|postorbital]] bears two branches that join with a gentle curve, separated by an angle of 130° in ''K. langenbergensis''. The [[supratemporal fenestra]] is roughly square in ''K. guimarotae''<ref name="guimarot"/> but has a thinner back end in ''K. langenbergensis''. In both species, the maximum distance between the supratemporal fenestrae is about a third of the total width of the top of the skull. The trapezoidal [[infratemporal fenestra]] is 1.5 times as long as it is wide in ''K. langenbergensis''.<ref name="desc"/>

===Palate and braincase===
On the bottom of the skull, the [[pterygoid bone|pterygoid]] is about twice as wide as it is long. At the front of the pterygoid is a small projection that extends backwards to form a ridge, on either side of which is a furrow-like depression (the choanal groove) containing the [[posterior nasal apertures|choanae]]. In ''Theriosuchus'', unlike ''Knoetschkesuchus'', the choanae are embedded in a wider bowl-like depression. Additionally, in both species, the bottom surface of the pterygoid is somewhat concave. Extending forward from either side of the pterygoid is the ectopterygoid; in both species, this bone is constricted near the middle to form an hourglass-like shape, but in ''K. langenbergensis'' it is also somewhat twisted to the side. The back of the bone is very concave in both species.<ref name="desc"/><ref name="guimarot"/>

[[File:Knoetschke-6.png|thumb|Photographs, interpretive drawings, and CT scans of the braincase and jaw of the juvenile skull of ''K. langenbergensis'']]
Forming the sides of the back of the skull is the [[occipital bone|exoccipital]], which surrounds most of the [[foramen magnum]]. The [[Eustachian tube]] extends downwards across the [[occipital bone|basoccipital]] and [[sphenoid bone|basisphenoid]]; these bones are thickened on either side of the tube in ''K. langenbergensis''. ''K. guimarotae'' has a small rounded foramen beside the tube on the basoccipital, and a tuberosity bearing a ridge above.<ref name="guimarot"/> On the front of the basoccipital in both species, there are two rounded depressions near the bottom. The basisphenoid resembles a triangular hatchet in shape when viewed from the side.<ref name="desc"/>

===Jaw===
In ''K. guimarotae'', the two halves of the dentary diverge from each other at an angle of 20° near the front, then 40° near the back.<ref name="guimarot"/> It also bears two convexities on the bottom of the jaw, one at the third and fourth teeth and another at the eighth to tenth teeth. The latter convexity is replaced by a concavity in ''K. langenbergensis''. In both species, the top margin of the jaw behind the tooth row slopes upwards in a straight line. The side of the dentary is pitted, albeit much more densely so in ''K. langenbergensis''. Near the back of the dentary in both species, the pits are replaced by longitudinal grooves. On the interior of the jaw, the [[splenial]] bears an oval foramen behind the level of the [[mandibular symphysis|symphysis]] in both species, and the top of the bone bears a low and roughened crest in ''K. guimarotae''.<ref name="desc"/><ref name="guimarot"/>

The tip of the angular is situated close to the midpoint of the bone in ''K. langenbergensis'' rather than being at the back as in ''K. guimarotae''.<ref name="guimarot"/> In both species, the back of the angular contributes to the retroarticular process. The inner surface of the angular is roughened in ''K. guimarotae'', and the top margin of the inner wall transitions from an upward-projecting tip at the front to a low, rounded crest at the back;<ref name="guimarot"/> the same margin maintains its height along the angular in ''K. langenbergensis''. The [[suprangular|surangular]] bears a thin, forward-projecting process that, in ''K. langenbergensis'', extends forward to the back of the tooth row and bears a groove on the bottom.<ref name="guimarot"/> The presence of the oval-shaped<ref name="guimarot"/> external mandibular fenestra is unique to the genus among atoposaurids.<ref name="desc"/>

===Teeth===
[[File:Theriosuchus guimarotae PB01-ATOP0001 A1.jpg|thumb|left|Photograph of the characteristic lancehead-shaped teeth of ''K. guimarotae'' from the back of the mouth]]
Both species of ''Knoetschkesuchus'' have only two distinct types of teeth, uniquely among atoposaurids. Other atoposaurids have a third type of leaf-shaped teeth. The first type of teeth, found near the front of the jaw, are conical, slightly constricted at the base, and curved slightly inwards.<ref name="guimarot"/> A subtype is represented by the canine-like or pseudocaniniform teeth. They are the fourth and fifth maxillary teeth, and are enlarged (about twice the size of the other maxillary teeth), more pointed, and more constricted at the base. The second type of teeth, which constitutes the rest of the teeth, are shaped like thin lanceheads, with a wide base and a narrower tip; in ''K. guimarotae'' all of the tips are sharp,<ref name="guimarot"/> but in ''K. langenbergensis'' they gradually become blunter.<ref name="desc"/>

There are 5 premaxillary teeth in both species,<ref name="guimarot"/> the fourth of which is about a third larger relative to the others. The maxilla has 12 distinct sockets in ''K. langenbergensis''. Excluding the pseudocaniniforms, the maxillary tooth size remains roughly constant but gradually decreases after the pseudocaniniforms in both species; all tooth sockets after the twelfth are replaced by a continuous trough. In total, ''K. guimarotae'' had at least 15 maxillary teeth,<ref name="guimarot"/> and ''K. langenbergensis'' 17 or 18. Meanwhile, the dentary exhibits 21 teeth in ''K. langenbergensis'' and at least 20 in ''K. guimarotae''.<ref name="guimarot"/> Like the maxilla, distinct sockets for dentary teeth are replaced by a groove from the eleventh tooth backwards in ''K. langenbergensis''.<ref name="desc"/>

==Classification==
[[File:Knoetschke-11.png|thumb|''Knoetschkesuchus langenbergensis'' compared with ''Theriosuchus pusillus'']]
When the known specimens of ''K. langenbergensis'' were first described in a preliminary fashion by a 2006 paper from Hans-Volker Karl ''et al.'', they were referred to the genus ''Theriosuchus''. This was on the basis of the short skull, divided nostrils, large eye sockets compared to the supratemporal fenestrae, and the bevelled side of the squamosal. Specifically, they recognized its similarity to ''T. pusillus'' on the basis of its osteoderms and teeth, although they noted that the orientation of the back of the skull was different and that leaf-shaped teeth were absent. These differences were attributed to ''K. langenbergensis'' probably representing a different life stage of ''T. pusillus'' compared to the type specimen.<ref name="karl2006">{{cite journal | last1 = Karl | first1 = H.-V. | last2 = Gröning | first2 = E. | last3 = Brauckmann | first3 = C. | last4 = Schwarz | first4 = D. | last5 = Knötschke | first5 = N. | title = The Late Jurassic crocodiles of the Langenberg near Oker, Lower Saxony (Germany), and description of related materials (with remarks on the history of quarrying the "Langenberg Limestone" and "Obernkirchen Sandstone") | journal = Clausthaler Geowissenschaften | volume = 5 | date = 2006 | pages = 59–77 | url = https://www.researchgate.net/publication/40663177}}</ref><ref name="tennant2016"/> A 2016 analysis of the relationships of the Atoposauridae, from Jonathan Tennant ''et al.'', tentatively supported the affinity of these specimens with ''T. pusillus'' on account of the teeth being situated in a groove (a trait uniting ''T. pusillus'' and ''"T." guimarotae'' in their analysis), the presence of pseudocaniniform teeth, and the lance head-shaped teeth near the back of the jaw. However, they noted that the nasals essentially completely divide the nostrils to the exclusion of other bones, which is not seen in the genus of ''Theriosuchus''.<ref name="tennant2016">{{cite journal | last1 = Tennant | first1 = J.P. | last2 = Mannion | first2 = P.D. | last3 = Upchurch | first3 = P. | title = Evolutionary relationships and systematics of Atoposauridae (Crocodylomorpha: Neosuchia): implications for the rise of Eusuchia | journal = Zoological Journal of the Linnean Society | volume = 177 | issue = 4 | date = 2016 | pages = 854–936 | doi = 10.1111/zoj.12400 | url = http://discovery.ucl.ac.uk/1513251/1/Tennant_et_al-2016-Zoological_Journal_of_the_Linnean_Society.pdf | doi-access = free }}</ref>

However, the taxonomy of ''Theriosuchus'' itself is somewhat convoluted. Many recent taxonomic studies have not provided an explicit set of characteristics that unite species of ''Theriosuchus'' and separate them from other atoposaurids;<ref name="young2016"/><ref name="nodiag1">{{cite journal | last1 = Martin | first1 = J.E. | last2 = Rabi | first2 = M. | last3 = Csiki-Sava | first3 = Z. | last4 = Vasile | first4 = S. | title = Cranial morphology of ''Theriosuchus sympiestodon'' (Mesoeucrocodylia, Atoposauridae) and the widespread occurrence of ''Theriosuchus'' in the Late Cretaceous of Europe | journal = Journal of Paleontology | volume = 88 | issue = 3 | date = 2014 | pages = 444–456 | doi = 10.1666/13-106 | s2cid = 128992853 }}</ref><ref name="nodiag2">{{cite journal | last1 = Lauprasert | first1 = K. | last2 = Laojumpon | first2 = C. | last3 = Saenphala | first3 = W. | last4 = Cuny | first4 = G. | last5 = Thirakhupt | first5 = K. | last6 = Suteethorn | first6 = V. | title = Atoposaurid crocodyliforms from the Khorat Group of Thailand: first record of ''Theriosuchus'' from Southeast Asia | journal = Paläontologische Zeitschrift | date = 2011 | volume = 85 | issue = 1 | pages = 37–47 | doi = 10.1007/s12542-010-0071-z | s2cid = 128623617 }}</ref> the only such diagnoses that have been produced were given by Steve Salisbury and [[Darren Naish]] in 2011,<ref name="salisburynaish">{{cite book | last1 = Salisbury | first1 = S.W. | last2 = Naish | first2 = D. | chapter = Crocodilians | date = 2011 | chapter-url = https://darrennaish.files.wordpress.com/2013/07/salisbury-naish-2011-wealden-crocodyliforms.pdf | pages = 305–369 | title = English Wealden Fossils | publisher = Palaeontological Association | location= London | editor-last1 = Batten | editor-first1 = D. | editor-last2 = Lane | editor-first2 = P.D. | url = http://www.palass.org/beta/eps/shop/product/english-wealden-fossils/ | isbn = 978-1-4443-6711-9}}</ref> and Jeremy Martin ''et al.'' in 2010.<ref name="martin2010">{{cite journal | last1 = Martin | first1 = J.E. | last2 = Rabi | first2 = M. | last3 = Cziki | first3 = Z. | title = Survival of ''Theriosuchus'' (Mesoeucrocodylia: Atoposauridae) in a Late Cretaceous archipelago: a new species from the Maastrichtian of Romania | journal = Naturwissenschaften | volume = 97 | issue = 9 | pages = 845–854 | date = 2010 | doi = 10.1007/s00114-010-0702-y | pmid = 20711558 | bibcode = 2010NW.....97..845M | s2cid = 32176974 }}</ref> In 2016 Mark Young ''et al.'' criticized these diagnoses, noting that many characters were either more widely distributed among the Atoposauridae, difficult to assess, or—in the case of the latter diagnosis—not present at all. Young ''et al.'' provided an alternative diagnosis containing nine traits, mostly involving teeth; however, they also noted that there was variation among the expression of these traits, which calls into question the [[monophyly]] of ''Theriosuchus''.<ref name="young2016">{{cite journal | last1 = Young | first1 = M.T. | last2 = Tennant | first2 = J.P. | last3 = Brusatte | first3 = S.L. | last4 = Challands | first4 = T.J. | last5 = Fraser | first5 = N.C. | last6 = Clark | first6 = N.D.L. | last7 = Ross | first7 = D.A. | title = The first definitive Middle Jurassic atoposaurid (Crocodylomorpha, Neosuchia), and a discussion on the genus ''Theriosuchus'' | journal = Zoological Journal of the Linnean Society | volume = 176 | issue = 2 | date = 2016 | pages = 443–462 | doi = 10.1111/zoj.12315 | pmid = 27594716 | pmc = 4989461 }}</ref> ''K. langenbergensis'' differs from this diagnosis in four out of nine traits,<ref name="young2016"/> which Schwarz ''et al.'' cited as a basis for both the generic separation of ''Knoetschkesuchus'' and the necessity of revising the diagnosis further.<ref name="desc"/>
[[File:Knoetschke-10.png|thumb|''Knoetschkesuchus langenbergensis'' compared with ''Knoetschkesuchus guimarotae'']]

According to Schwarz ''et al.'', seven traits unite ''K. langenbergensis'' and ''K. guimarotae'', and separate them from other species referred to ''Theriosuchus''. These include the presence of only two unique tooth morphotypes; the choanae being placed in shallow grooves rather than a bowl-like depression; the relatively wide top of the skull; the presence of antorbital and mandibular fenestrae in all life stages; and the relatively limited contact between the lacrimal and nasal. Additionally, ''K. langenbergensis'' differs from other species in lacking teeth with low crowns; having a longer maxillary symphysis; having a crest on the side of the downward-projecting process of the postorbital; having overlap between the postorbital and the front of the squamosal; and a rectangular parietal that does not form part of the supratemporal fenestra.<ref name="desc"/>

In the 2017 description of ''K. langenbergensis'', Schwarz ''et al.'' used the 2015 [[phylogenetics|phylogenetic]] dataset of Alan Turner,<ref name="turner2015">{{cite journal | last1 = Turner | first1 = A.H. | title = A Review of ''Shamosuchus'' and ''Paralligator'' (Crocodyliformes, Neosuchia) from the Cretaceous of Asia | journal = PLOS ONE | volume = 10 | issue = 2 | page = e0118116 | date = 2015 | doi = 10.1371/journal.pone.0118116 | pmid = 25714338 | pmc = 4340866 | bibcode = 2015PLoSO..1018116T | doi-access = free }}</ref> which was revised to remove irrelevant characteristics, add ''K. langenbergensis'' and ''T. grandinaris'', and correct flaws in the coded traits of ''K. guimarotae'' (due to low-resolution images, inaccuracies in the original reconstruction, and the acquirement of new data). The phylogenetic trees recovered by this analysis consistently found that Atoposauridae, represented by ''Knoetschkesuchus'', ''Theriosuchus'', and ''Alligatorium'', forms a monophyletic clade. Within this clade, a close relationship between ''K. langenbergensis'' and ''K. guimarotae'', excluding other ''Theriosuchus'' species, was strongly supported, providing further evidence of these two species forming a separate genus. In some trees, ''T. grandinaris'' was also close to ''Knoetschkesuchus''. The [[maximum parsimony (phylogenetics)|most parsimonious]] arrangement is reproduced below.<ref name="desc"/>

{{clade| style=font-size:85%; line-height:85%
|label1=[[Eusuchia]]
|1={{clade
      |1={{clade
         |2={{clade
            |1={{clade
               |1=''[[Allodaposuchus|Allodaposuchus subjuniperus]]''
               |2=''[[Allodaposuchus|Allodaposuchus precedens]]''}}
            |2={{clade
               |label1=[[Atoposauridae]]
               |1={{clade
                  |1=''[[Theriosuchus|Theriosuchus symphiestodon]]''
                  |2={{clade
                     |1={{clade
                        |1=''[[Theriosuchus|Theriosuchus pusillus]]''
                        |2=''[[Alligatorium|Alligatorium spp.]]''}}
                     |2={{clade
                        |label2='''''Knoetschkesuchus'''''
                        |1=''[[Theriosuchus|Theriosuchus grandinaris]]''
                        |2={{clade
                           |1='''''Knoetschkesuchus langenbergensis'''''
                           |2='''''"Theriosuchus" guimarotae'''''}}}}}}}}
               |2=[[Paralligatoridae]]}}}}
         |1={{clade
            |1=''[[Pachycheilosuchus|Pachycheilosuchus trinquel]]''
            |2={{clade
               |1={{clade
                  |1=''[[Isisfordia|Isisfordia duncani]]''
                  |2={{clade
                     |1={{clade
                        |1=''[[Acynodon|Acynodon adriaticus]]''
                        |2=''[[Acynodon|Acynodon iberoccitanus]]''}}
                     |2={{clade
                        |1=''[[Susisuchus|Susisuchus anatoceps]]''
                        |2={{clade
                           |1=''[[Iharkutosuchus|Iharkutosuchus makadii]]''
                           |2=''[[Hylaeochampsa|Hylaeochampsa vectiana]]''}}}}}}}}}}}}}}
      |2=[[Crocodylia]]}}}}

==Paleoecology==
Being relatively small, ''Knoetschkesuchus'' would have mainly fed on invertebrates and possibly small vertebrates (including amphibians and mammals). The same diet is observed in modern juvenile crocodilians of the same size class.<ref name="guimarot"/>

[[File:Alligatorellus-1.jpg|thumb|Localities of Late Jurassic atoposaurids shown on present-day (a) and Late Jurassic (b) maps]]
During the Kimmeridgian, Europe was covered by the shallow [[inland sea (geology)|inland]] [[Tethys Ocean]], with exposed landmasses being a series of scattered archipelagos.<ref name="tethys1">{{cite book | last1 = Fourcade | first1 = E. | last2 = Azéma | first2 = J. | last3 = Bassoullet | first3 = J.-P. | last4 = Cecca | first4 = F. | last5 = Dercourt | first5 = J. | last6 = Enay | first6 = R. | last7 = Guiraud | first7 = R. | chapter = Paleogeography and Paleoenvironment of the Tethyan Realm During the Jurassic Breakup of Pangea | pages = 191–214 | title = The Tethys Ocean | date = 1996 | doi = 10.1007/978-1-4899-1558-0_6 | isbn = 9781489915603 | publisher = Springer US | editor-last1 = Nairn | editor-first1 = A.E.M. | editor-last2 = Ricou | editor-first2 = L.-E. | editor-last3 = Vrielynck | editor-first3 = B. | editor-last4 = Dercourt | editor-first4 = J. | chapter-url = https://link.springer.com/book/10.1007/978-1-4899-1558-0 }}</ref><ref name="tethys2">{{cite book | last1 = Smith | first1 = A.G. | last2 = Smith | first2 = D.G. | last3 = Funnell | first3 = B.M. | title = Atlas of Mesozoic and Cenozoic Coastlines | date = 2004 | isbn = 9780521602877 | url = http://www.cambridge.org/us/academic/subjects/earth-and-environmental-science/sedimentology-and-stratigraphy/atlas-mesozoic-and-cenozoic-coastlines?format=PB&isbn=9780521602877 | publisher = Cambridge University Press | location = Cambridge}}</ref> Highly variable sea levels<ref name="sealevels">{{cite journal | last1 = Miller | first1 = K.G. | last2 = Kominz | first2 = M.A. | last3 = Browning | first3 = J.V. | last4 = Wright | first4 = J.D. | last5 = Mountain | first5 = G.S. | last6 = Katz | first6 = M.E. | last7 = Sugarman | first7 = P.J. | last8 = Cramer | first8 = B.S. | last9 = Christie-Blick | first9 = N. | last10 = Pekar | first10 = S.F. | title = The Phanerozoic Record of Global Sea-Level Change | journal = Science | volume = 310 | issue = 5752 | pages = 1293–1298 | date = 2005 | doi = 10.1126/science.1116412 | pmid = 16311326 | bibcode = 2005Sci...310.1293M | s2cid = 7439713 | url = https://academiccommons.columbia.edu/doi/10.7916/D8C53WV8/download }}</ref> supported a highly diverse insular crocodilian fauna, with biodiversity (that of atoposaurids in particular) being driven strongly by [[allopatric speciation]].<ref name="alligatorellus">{{cite journal | last1 = Tennant | first1 = J.P. | last2 = Mannion | first2 = P.D. | title = Revision of the Late Jurassic crocodyliform ''Alligatorellus'', and evidence for allopatric speciation driving high diversity in western European atoposaurids | journal = PeerJ | date = 2014 | volume = 2 | page = e599 | doi = 10.7717/peerj.599 | pmid = 25279270 | pmc = 4179893 | doi-access = free }}</ref> The two species of ''Knoetschkesuchus'' were part of similar faunas, in both of which they functioned as small predators [[niche differentiation|ecologically partitioned]] from the other contemporary crocodilians; it is likely that these faunas originated through dispersal over larger landmasses.<ref name="desc"/> A similar faunal exchange occurred with the [[Wessex Formation|Wessex]]-[[Wealden Formation|Weald]] Basin of [[England]].<ref name="wessexgonio">{{cite journal | last1 = Salisbury | first1 = S.W. | last2 = Willis | first2 = P.M.A. | last3 = Peitz | first3 = S. | last4 = Sander | first4 = P.M. | date = 1999 | title = The crocodilian ''Goniopholis simus'' from the Lower Cretaceous of north-western Germany | journal = Special Papers in Palaeontology | volume = 60  | pages = 121–148 | url = https://www.researchgate.net/publication/260391546}}</ref>

===''K. langenbergensis''===
The Langenberg Quarry, where ''K. langenbergensis'' is known from, is part of the Lower Saxony Basin, which would have been part of the landmass associated with the Rhenisch, Bohemian, and London-Brabant [[Massif]]s. During the Kimmeridgian, it would have been a shallow marine environment; however, this does not imply that ''K. langenbergensis'' was marine, since the animals and plants of the Langenberg Quarry were probably transported [[allochthon]]ously (albeit only by a short distance) from the surrounding islands. Brackish and freshwater sediments are also present in the quarry, which implies that there was occasional freshwater influx.<ref name="desc"/> Twigs and conifer cones indicate that the [[araucariaceae|araucarian]] ''[[Brachyphyllum]]'' was present at the site.<ref name="langoverview"/>
[[File:Machimosaurus illustration.jpg|thumb|Reconstruction of ''[[Machimosaurus]]'' species; ''M. hugii'' was present alongside both ''Knoetschkesuchus'' species]]

Besides ''K. langenbergensis'', other crocodilians from the Langenberg Quarry include the marine ''[[Machimosaurus|Machimosaurus hugii]]'' and ''[[Steneosaurus|Steneosaurus aff. brevirostris]]'',<ref name="karl2006"/> which would have lived offshore and fed on turtles and fish; and the amphibious generalist ''[[Goniopholis|Goniopholis simus]]'',<ref name="karl2006"/> which subsisted on a diet of both shelly and soft prey like modern alligators.<ref name="desc"/> The quarry is best known as the type locality of the [[brachiosauridae|brachiosaurid]] [[sauropoda|sauropod]] [[dinosaur]] ''[[Europasaurus|Europasaurus holgeri]]'', which was an [[insular dwarfism|insular dwarf]].<ref name="europa">{{cite journal | last1 = Sander | first1 = P.M. | last2 = Mateus | first2 = O. | last3 = Laven | first3 = T. | last4 = Knötschke | first4 = N. | title = Bone histology indicates insular dwarfism in a new Late Jurassic sauropod dinosaur | journal = Nature | volume = 441 | issue = 7094 | pages = 739–741 | date = 2006 | doi = 10.1038/nature04633 | pmid = 16760975 | bibcode = 2006Natur.441..739M | s2cid = 4361820 }}</ref> Isolated teeth show that there were at least four different types of [[theropoda|theropods]] present at the locality, including the [[megalosauridae|megalosaurid]] ''[[Torvosaurus|Torvosaurus sp.]]'' as well as an additional megalosaurid and indeterminate members of the [[Allosauridae]] and [[Ceratosauria]];<ref name="theroteeth">{{cite journal | last1 = Gerke | first1 = O. | last2 = Wings | first2 = O. | title = Multivariate and Cladistic Analyses of Isolated Teeth Reveal Sympatry of Theropod Dinosaurs in the Late Jurassic of Northern Germany | journal = PLOS ONE | volume = 11 | issue = 7 | page = e0158334 | doi = 10.1371/journal.pone.0158334 | pmid = 27383054 | pmc = 4934775 | year = 2016 | bibcode = 2016PLoSO..1158334G | doi-access = free }}</ref> theropod tracks from two different species (not identifiable to the family level) are also known.<ref name="tracks"/> Remains attributable to [[diplodocid]]s (possibly also dwarfed) and [[stegosauria|stegosaurs]] have also been found,<ref name="langoverview"/> alongside an indeterminate [[dsungaripteridae|dsungaripterid]] [[pterosaur]].<ref name="pterosaur">{{cite journal | last1 = Fastnacht | first1 = M. | title = The first dsungaripterid pterosaur from the Kimmeridgian of Germany and the biomechanics of pterosaur long bones | journal = Acta Palaeontologica Polonica | volume = 50 | issue = 2 | date = 2005 | pages = 273–288 | url = https://www.app.pan.pl/article/item/app50-273.html}}</ref>

Non-archosaurs are also present in the Langenberg Quarry. These include a [[paramacellodidae|paramacellodid]] [[lizard]];<ref name="lizard">{{cite conference | last1 = Richter | first1 = A. | last2 = Knötschke | first2 = N. | last3 = Kosma | first3 = R. | last4 = Sobral | first4 = G. | last5 = Wings | first5 = O. | title = The first Mesozoic lizard from northern Germany (Paramacellodidae, Late Jurassic, Langenberg Quarry) and its taphonomy | conference = 73rd Annual Meeting of the Society of Vertebrate Paleontology | url = http://vertpaleo.org/PDFs/SVP-2013-merged-book-10-15-2013.aspx | date = 2013 | page = 198 | location = Los Angeles | publisher = Society of Vertebrate Paleontology | access-date = 2017-03-20 | archive-date = 2016-03-05 | archive-url = https://web.archive.org/web/20160305133646/http://vertpaleo.org/pdfs/svp-2013-merged-book-10-15-2013.aspx | url-status = dead }}</ref> the [[turtle]]s ''[[Thalassemys|Thalassemys sp.]]'',<ref name="turtle">{{cite conference | last1 = Marinheiro | first1 = J. | last2 = Mateus | first2 = O. | title = Occurrence of the marine turtle ''Thalassemys'' in the Kimmeridgian of Oker, Germany | conference = 71st Annual Meeting of the Society of Vertebrate Paleontology | url = http://docentes.fct.unl.pt/sites/default/files/omateus/files/marinheiro__mateus_2011_turtle_thalassemys_oker_germany_svp11abstracts.pdf | date = 2011 | page = 151 | location = Las Vegas | publisher = Society of Vertebrate Paleontology}}</ref> ''[[Plesiochelys|Plesiochelys etalloni]]'',<ref name="turtle2">{{cite journal | last1 = Karl | first1 = H.-V. | title = Bite Traces in a Turtle Shell Fragment from the Kimmeridgian (Upper Jurassic) of Northern Germany | journal = Studia Geologica Salmanticensia | volume = 9 | date = 2012 | url = http://revistas.usal.es/index.php/Palaeocheloniologica/article/download/9213/9473 | pages = 25–30 | issn = 0211-8327}}</ref> and a juvenile [[cryptodira|eucryptodira]]n;<ref name="turtle3">{{cite journal | last1 = Jansen | first1 = M. | last2 = Klein | first2 = N. | title = A juvenile turtle (Testudines, Eucryptodira) from the Upper Jurassic of Langenberg Quarry, Oker, Northern Germany | journal = Palaeontology | volume = 57 | issue = 4 | date = 2014 | pages = 743–756 | doi = 10.1111/pala.12085 | s2cid = 128991586 | doi-access = free }}</ref> [[plagiaulacida|plagiaulacid]] [[multituberculata|multituberculate]],<ref name="memel">{{cite journal | last1 = Martin | first1 = M. | last2 = Schultz | first2 = J.A. | last3 = Schwermann | first3 = A.H. | last4 = Wings | first4 = O. | title = First Jurassic mammals of Germany: Multituberculate teeth from the Late Jurassic Langenberg Quarry near Goslar (Lower Saxony) | journal = Palaeontologia Polonica | volume = 67 | pages = 171–179 | url = http://www.palaeontologia.pan.pl/PP67/Martin.pdf}}</ref> [[dryolestida|dryolestid]], and [[docodontidae|docodont]] [[mammal]]s known from teeth;<ref name="langoverview">{{cite conference | last1 = Wings | first1 = O. | title = The Langenberg Quarry near Goslar: Unique window into a terrestrial Late Jurassic ecosystem in Northern Germany | date = 2015 | conference = 12th Symposium on Mesozoic Terrestrial Ecosystems | location = Shenyang | pages = 99–100 | url = https://www.researchgate.net/publication/281280039 | publisher = Paleontological Museum of Liaoning}}</ref> the [[mammaliaformes|mammaliaform]] ''[[Storchodon]]'';<ref>{{cite journal | first1 = T. | last1 = Martin | first2 = A.O. | last2 = Averianov | first3 = K.R.K. | last3 = Jäger | first4 = A.H. | last4 = Schwermann | first5 = O. | last5 = Wings | year = 2019 | title = A large morganucodontan mammaliaform from the Late Jurassic of Germany | journal = Fossil Imprint | volume = 75 | issue = 3–4 | pages = 504–509 | doi = 10.2478/if-2019-0030| doi-access = free }}</ref> a diverse [[actinopterygii|actinopterygian]] fish fauna dominated by ''[[Lepidotes|Lepidotes sp.]]'' but also including ''[[Macromesodon|Macromesodon sp.]]'', ''[[Proscinetes|Proscinetes sp.]]'', ''[[Coelodus|Coelodus sp.]]'', ''[[Macrosemius|Macrosemius sp.]]'' (or ''[[Notagogus|Notagogus sp.]]''), ''[[Histionotus|Histionotus sp.]]'', ''[[Ionoscopus|Ionoscopus sp.]]'', ''[[Callopterus|Callopterus sp.]]'', ''[[Caturus|Caturus sp.]]'', ''[[Sauropsis|Sauropsis sp.]]'', ''[[Belonostomus|Belonostomus sp.]]'', and ''[[Thrissops|Thrissops subovatus]]'';<ref name="actinopterygii">{{cite journal | last1 = Mudroch | first1 = A. | last2 = Thies | first2 = D. | title = Knochenfischzähne (Osteichthyeso Actinopterygii) aus dem Oberjura (Kimmeridgium) des Langenbergs bei Oker (Norddeutschland) | language = German | trans-title = Bony fishes (Osteichthyes, Actinopterygii) from the Upper Jurassic (Kimmeridgian) of the Langenberg Quarry at Oker (Northern Germany) | journal = Geologica et Palaeontologica | volume = 30 | pages = 239–265 | date = 1996 | url = https://www.researchgate.net/publication/288261589}}</ref> and five morphotypes of [[hybodontiformes|hybodonts]] plus the [[neoselachii|neoselachians]] ''[[Palaeoscyllium|Palaeoscyllium sp.]]'', two distinct ''[[Synechodus|Synechodus sp.]]'', and two distinct ''[[Asterodermus|Asterodermus sp.]]''<ref name="shark">{{cite journal | last1 = Thies | first1 = D. | title = Placoid scales (Chondrichthyes: Elasmobranchii) from the Late Jurassic (Kimmeridgian) of northern Germany | journal = Journal of Vertebrate Paleontology | volume = 15 | date = 1995 | issue = 3 | pages = 463–481 | doi = 10.1080/02724634.1995.10011242 }}</ref>

===''K. guimarotae''===
[[File:Mangrove swamp, Iriomote Island, Okinawa, Japan.jpg|thumb|A modern [[mangrove swamp]]; ''K. guimarotae'' would have inhabited a similar environment]]
The Guimarota locality is located in the eastern Lusitanian Basin, which is part of the Iberian Meseta.<ref name="desc"/> The vertebrate-bearing Guimarota-strata was deposited in a brackish [[lagoon]] that periodically received both freshwater and saltwater influxes.<ref name="schudack1"/> Ecologically, the environment would have been akin to a modern [[mangrove]] swamp.<ref name="martingui">{{cite book | last1 = Martin | first1 = T. | pages = 143–146 | date = 2000 | chapter = Overview over the Guimarota ecosystem | title = Guimarota – A Jurassic Ecosystem | editor-last1 = Martin | editor-first1 = T. | editor-last2 = Krebs | editor-first2 = B. | chapter-url = http://www.pfeil-verlag.de/07pala/e2_80.html | isbn = 9783931516802 | publisher = Verlag Dr. Friedrich Pfeil | location = München}}</ref><ref name="gloygui">{{cite book | last1 = Gloy | first1 = G. | pages = 129–136 | date = 2000 | chapter = Taphonomy of the fossil lagerstatte Guimarota | title = Guimarota – A Jurassic Ecosystem | editor-last1 = Martin | editor-first1 = T. | editor-last2 = Krebs | editor-first2 = B. | chapter-url = http://www.pfeil-verlag.de/07pala/e2_80.html | isbn = 9783931516802 | publisher = Verlag Dr. Friedrich Pfeil | location = München}}</ref> Plants known from megafossils include the horsetails ''[[Equisetum]]'' and ''[[Schizoneura]]''; the [[pteridospermatophyta|seed fern]] ''[[Caytonia]]''; the [[cycad]] ''[[Otozamites]]''; the araucaria ''Brachyphyllum''; ''[[Ginkgo]]''; and the [[charophyta|charophyte]] [[algae]] ''[[Porochara]]''. Additionally, plant families known only from pollen include [[lycopodiophyta|lycopods]], [[gleicheniaceae|forked ferns]], possible [[cyatheaceae|scaly tree ferns]] (which may be [[matoniaceae|matoniaceans]] or [[dicksoniaceae|dicksoniaceans]] instead), [[osmundaceae|royal ferns]], the [[seed fern]] ''[[Sphenopteris]]'', [[cupressaceae|cypresses]], and [[pinaceae|pines]].<ref name="plants">{{cite journal | last1 = van Erve | first1 = A. | last2 = Mohr | first2 = B. | title = Palynological investigation of the Late Jurassic microflora from the vertebrate locality Guimarota coal mine (Leiria, Central Portugal) | journal = Neues Jahrbuch für Geologie und Paläontologie - Monatshefte | volume = 1988 | issue = 4 | date = 1988 | pages = 246–262 | doi = 10.1127/njgpm/1988/1988/246 | url = https://www.researchgate.net/publication/302927988}}</ref> Most of the preserved organisms probably originated from around the swamp, although there may have been minimal transportation by water currents.<ref name="gloygui"/>

Many crocodilians are known from the Guimarota mine. The marine ''Machimosaurus hugii'' is again present,<ref name="guicroc">{{cite book | last1 = Krebs | first1 = B. | last2 = Schwarz | first2 = D. | pages = 69–74 | date = 2000 | chapter = The crocodiles from the Guimarota mine | title = Guimarota – A Jurassic Ecosystem | editor-last1 = Martin | editor-first1 = T. | editor-last2 = Krebs | editor-first2 = B. | chapter-url = http://www.pfeil-verlag.de/07pala/e2_80.html | isbn = 9783931516802 | publisher = Verlag Dr. Friedrich Pfeil | location = München}}</ref> as is ''Goniopholis'' (although as a different species, ''G. baryglyphaeus'').<ref name="goniogui">{{cite journal | last1 = Schwarz | first1 = D. | title = A New Species of ''Goniopholis'' from the Upper Jurassic of Portugal | journal = Palaeontology | volume = 45 | issue = 1 | date = 2002 | pages = 185–208 | doi = 10.1111/1475-4983.00233 | s2cid = 128623921 | url = http://doc.rero.ch/record/14778/files/PAL_E1906.pdf }}</ref> Additionally, ''[[Bernissartia|Bernissartia sp.]]'', ''[[Lisboasaurus|Lisboasaurus estesi]]'', and ''[[Lusitanisuchus|Lusitanisuchus mitracostatus]]'' have also been found;<ref name="lusita">{{cite journal | last1 = Schwarz | first1 = D. | last2 = Fechner | first2 = R. | title = ''Lusitanisuchus'', a new generic name for ''Lisboasaurus mitracostatus'' (Crocodylomorpha: Mesoeucrocodylia), with a description of new remains from the Upper Jurassic (Kimmeridgian) and Lower Cretaceous (Berriasian) of Portugal | journal = Canadian Journal of Earth Sciences | volume = 41 | issue = 10 | date = 2004 | pages = 1259–1271 | doi = 10.1139/e04-059 | bibcode = 2004CaJES..41.1259S }}</ref> the latter two were small, being less than {{convert|50|cm}} in length, and likely also fed on insects like ''K. guimarotae''.<ref name="desc"/> Dinosaurs from Guimarota are mainly known from teeth, and include a brachiosaurid, which is also rather small in size; theropods, including ''[[Stokesosaurus|Stokesosaurus sp.]]'' (known from body fossils), ''[[Compsognathus|Compsognathus sp.]]'', allosaurids, a ceratosaur similar to ''[[Ceratosaurus]]'', a taxon similar to the phylogenetically problematic ''[[Richardoestesia]]'', dromaeosaurids, [[troodontidae|troodontids]], and [[archaeopterygidae|archaeopterygiforms]]; and the [[ornithopod]]s ''[[Phyllodon|Phyllodon henkeli]]'' and an [[iguanodontidae|iguanodont]] similar to ''[[Camptosaurus]]''.<ref name="guidino">{{cite book | last1 = Rauhut | first1 = O.W.M. | pages = 75–82 | date = 2000 | chapter = The dinosaur fauna from the Guimarota mine | title = Guimarota – A Jurassic Ecosystem | editor-last1 = Martin | editor-first1 = T. | editor-last2 = Krebs | editor-first2 = B. | url = http://www.pfeil-verlag.de/07pala/e2_80.html | isbn = 9783931516802 | publisher = Verlag Dr. Friedrich Pfeil | location = München | chapter-url = https://www.researchgate.net/publication/235907491}}</ref> Other diverse vertebrates, including [[chondrichthyes|chondrichthyans]], [[osteichthyes|osteichthyans]], [[albanerpetontidae|albanerpetontid]] [[amphibian]]s, turtles, lizards, [[rhamphorhynchidae|rhamphorhynchid]] pterosaurs, and docodont and dryolestid mammals (including ''[[Henkelotherium|Henkelotherium guimarotae]]'') are also present. Invertebrates are represented by ostracods and [[mollusc]]s.<ref name="desc"/>

==References==
{{Reflist|2}}
{{Portal|Paleontology}}

{{Neosuchia|N.}}
{{Taxonbar|from=Q28793835}}

[[Category:Late Jurassic crocodylomorphs]]
[[Category:Late Jurassic reptiles of Europe]]
[[Category:Atoposaurids]]
[[Category:Fossil taxa described in 2017]]
[[Category:Prehistoric pseudosuchian genera]]