# Muensterella > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Muensterella > Markdown URL: https://mediated.wiki/source/Muensterella.md > Source: https://en.wikipedia.org/wiki/Muensterella > Source revision: 1344578897 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) {{Short description|Extinct genus of molluscs}} {{Automatic taxobox | fossil_range = [Kimmeridgian](/source/Kimmeridgian)-[Turonian](/source/Turonian)
~{{Fossil range|155|90}} | image = Specimen BSPG MC-21 of Muensterella scutellaris.png | image_caption = Fossil specimen BSPG MC-21 of ''Muensterella scutellaris'' | image2 = Reconstruction of Muensterella scutellaris.png | image2_caption = ''Muensterella scutellaris'' diagram depicting soft tissue and gladius | taxon = Muensterella | authority = Schevill, 1950 | type_species = '''''Muensterella scutellaris''''' | type_species_authority = Münster, 1842 | subdivision_ranks = Species | subdivision = * ''Muensterella scutellaris'' {{small|Münster, 1842}} * ''Muensterella spinosa'' {{small|Fuchs ''et al.'', 2019}} * ''Muensterella jillae'' {{small|Fuchs ''et al.'', 2019}} | synonyms = * ''Kelaeno'' {{small|Münster, 1842}} ([preoccupied](/source/Kelaeno)) }} '''''Muensterella''''' ({{IPA|und|ˈmʏns.tɐ.ɛl.la}}) (meaning "Münster's small one") is an extinct genus of small [muensterellid](/source/Muensterellidae) [cephalopod](/source/cephalopod), which superficially resembles [cuttlefish](/source/cuttlefish) or [bobtail squid](/source/bobtail_squid) but are actually more closely related to [vampire squid](/source/vampire_squid). Fossils of this genus have primarily been found in the [Upper Jurassic](/source/Late_Jurassic) [lithographic limestone](/source/lithographic_limestone)s of [Southern Germany](/source/Southern_Germany), and additional material is known from the [Tithonian](/source/Tithonian) of [Antarctica](/source/Antarctica) and the [Upper Cretaceous](/source/Late_Cretaceous) of Germany and Texas.{{Cite journal |last=Fuchs |first=Dirk |last2=Iba |first2=Yasuhiro |last3=Heyng |first3=Alexander |last4=Iijima |first4=Masaya |last5=Klug |first5=Christian |last6=Larson |first6=Neal L. |last7=Schweigert |first7=Günter |date=2020 |title=The Muensterelloidea: phylogeny and character evolution of Mesozoic stem octopods |url=https://onlinelibrary.wiley.com/doi/abs/10.1002/spp2.1254 |journal=Papers in Palaeontology |language=en |volume=6 |issue=1 |pages=31–92 |doi=10.1002/spp2.1254 |issn=2056-2802|url-access=subscription }} == History == The fossil that would later be known as ''Muensterella scutellaris'' was first [described](/source/Species_description) by the German palaeontologist [Georg Graf zu Münster](/source/Georg_zu_M%C3%BCnster) in 1842 based on the fossil material from the [Solnhofen lithographic limestones](/source/Solnhofen_Limestone) in [Bavaria](/source/Bavaria) as ''Kelaeno arquata.'' However, the genus ''Kelaeno'' as named by Münster is a younger [homonym](/source/homonym) of ''[Kelaeno](/source/Kelaeno)'' named by [d’Orbigny](/source/Alcide_d'Orbigny) in 1841. Therefore, ''Kelaeno'' Münster, 1843, and the family name Kelaenidae Naef, 1921, had to be replaced by younger [synonyms](/source/Synonym_(taxonomy)), which are ''Muensterella'', as described by Schevill in 1950, and [Muensterellidae](/source/Muensterellidae) Roger, 1952. Previously it had been erroneously assumed that the [holotype](/source/holotype), later designated as MfN MB.c.1023, had been destroyed in [WW2](/source/World_War_II) during the [RAF](/source/Royal_Air_Force) [bombing raid](/source/Strategic_bombing) on the [Paleontological Museum in Munich](/source/Palaeontological_Museum%2C_Munich). Later research by Fuchs et al. in 2003 illustrated what they thought was the [counterpart](/source/Compression_fossil) of the holotype, which they found in the [Museum of Natural History Berlin](/source/Natural_History_Museum%2C_Berlin). Subsequently, said specimen was proven to in fact be the holotype itself; the error was caused by the fact that the original drawings published by Münster back in 1842 were mirrored, making the actual holotype appear to be its counterpart. In 2019 a comprehensive paper on the evolution and [phylogeny](/source/phylogeny) of the [Muensterelloidea](/source/Muensterelloidea) by Fuchs et al. named two further species of ''Muensterella:'' ''M. spinosa'' from the Tithonian of Daiting, [Mörnsheim Formation](/source/M%C3%B6rnsheim_Formation) in Bavaria, and ''M. jillae'' from the [middle Turonian](/source/Turonian) [South Bosque Formation](/source/South_Bosque_Formation) of Texas. == Description == left|thumb|Detailed morphology and measurements of the gladius of ''Muensterella scutellaris''Most fossil cephalopods are primarily known from the remains of their hard parts, usually the [gladius](/source/Gladius_(cephalopod)), a mostly thin, flexible internal [shell](/source/Mollusc_shell) that provides structural support and helps maintain the body shape, or the [beak](/source/Cephalopod_beak). Specimens of ''Muensterella'' are usually [preserved in a lateral position](/source/Taphonomy); dorsal or ventral views which would better preserve the detailed anatomy of the gladius are rarer. Several very well-preserved specimens of ''M. scutellaris'' from the [Solnhofen Limestone](/source/Solnhofen_Limestone) offer a detailed insight into the [soft tissue](/source/soft_tissue) anatomy of this genus.Coleoid cephalopods through time (Warnke K., Keupp H., Boletzky S. v., eds) Berliner Paläobiol. Abh. 03 101-111 Berlin 2003 New Records of Soft Parts of Muensterella scutelaris Muenter, 1842 (Coleoidea) From the Late Jurassic Plattenkalks of Eichstätt and Their Significance for Octobrachian Relationships. D. Fuchs*, H. Keupp & Th. Engeser === Gladius === In [muensterelloids](/source/Muensterelloidea) such as ''Muensterella'', the [gladius](/source/Gladius_(cephalopod)) can be subdivided into an anterior free median field (or [rachis](/source/rachis)) and a posterior patella.{{Cite journal |last=Fuchs |first=Dirk |date=2016-09-19 |title=Treatise Online No. 83: Part M, Chapter 9B: The Gladius and Gladius Vestige in Fossil Coleoidea |url=https://journals.ku.edu/treatiseonline/article/view/6488 |journal=Treatise Online |language=en |doi=10.17161/to.v0i0.6488 |issn=2153-4012}} In ''M. scutellaris'' the patella is shaped like a long oval; its apex is located in its anterior half. The margins of the patella as well as its dorsal surface are smooth and lack tubercles or radial ribs. The slender and moderately wide median field expresses itself as a keel-like elevation above the depressed hyperbolar zone, which is the part of the rachis enclosed by the patella. The free rachis is slightly shorter than the patella. ''M. spinosa'' is very similar in its morphology to ''M. scutellaris'', but its gladius exhibits spine-like structures on its dorsal surface as well as faint ribs radiating from the apex of the patella, a trait unique amongst other muensterelloids. ''M. jillae'' is also very similar in its gladius shape to the type species, but the apex of its conus is more posterior, and the species is far larger as a whole.{{Cite journal |last=Fuchs |first=Dirk |date=2020-09-21 |title=Treatise Online no. 138: Part M, Chapter 23G: Systematic Descriptions: Octobrachia |url=https://journals.ku.edu/treatiseonline/article/view/14661 |journal=Treatise Online |language=en |doi=10.17161/to.vi.14661 |issn=2153-4012}} === Mantle and head === The [mantle](/source/Mantle_(mollusc)) musculature of gladius-bearing cephalopods like ''Muensterella'' usually corresponds to the gladius length. In the specimen MC-51 of ''M. scutellaris,'' the mantle's musculature is almost completely preserved: a muscular mantle can be recognised in the fossil by the striated appearance created by the alternation of circular and radial muscles, which in modern cephalopods are continuous around the mantle. In ''Muensterella'' however, they extend for only a short distance, which may be the more [basal state](/source/Basal_(phylogenetics)) compared to modern taxa.{{Cite journal |last=Donovan |first=Desmond T. |last2=Fuchs |first2=Dirk |date=2016-09-19 |title=Treatise Online no. 73: Part M, Chapter 13: Fossilized Soft Tissues in Coleoidea |url=https://journals.ku.edu/treatiseonline/article/view/5675 |journal=Treatise Online |language=en |doi=10.17161/to.v0i0.5675 |issn=2153-4012}} It has been previously assumed that the imprints seen in the fossils indicate a squat body, but the preserved mantle tissues instead point to a comparatively slender body shape. Similar to modern representatives of the Octopodiformes, ''Muensterella'' appears to exhibit a head-mantle fusion, meaning there is no visible divide between the head and the mantle and the absence of a "neck", unlike in [squid](/source/squid) and [cuttlefish](/source/cuttlefish). In some Solnhofen specimens, what is interpreted to be a strand of muscular tissue usually running in anterioposterior directions might possibly represent the [funnel retractor](/source/Siphon_(mollusc)), a muscle that pulls the funnel (or siphon) backward, helping control the direction and force of water expelled for jet propulsion and manoeuvring. ==== Mantle fins ==== thumb|Specimen of ''Muensterella scutellaris'' in left lateral view showing imprints of skirtlike fins, with arrow marking position of funnel retractorIn the original description by Münster, he interpreted the fossil as showing a squat body shape and lacking any signs of [fins](/source/Cephalopod_fin). Later reinterpretations of the holotype and additional material show a slight ridge running along the outline of the body, starting at the posterior ventral part of the conus and running up to the head region. The region separated from the mantle by the ridge does not show the same well-preserved musculature as is typical for the mantle; hence, this region has been interpreted as the remains of the mantle fins, which exhibit musculature which are not as well developed as the mantle's musculature, and thus were not preserved. Entirely unique in octopodiformes, ''Muensterella'' appears to exhibit marginal fringing or skirt-like fins similar to representatives of the [Sepiidae](/source/Sepiidae) (cuttlefish).Fuchs, Dirk; Iba, Yasuhiro; Tischlinger, Helmut; Keupp, Helmut; Klug, Christian (2016). "The locomotion system of Mesozoic Coleoidea (Cephalopoda) and its phylogenetic significance". ''Lethaia''. '''49''' (4): 433–454. [Bibcode](/source/Bibcode_(identifier)):2016Letha..49..433F. [doi](/source/Doi_(identifier)):10.1111/let.12155. [ISSN](/source/ISSN_(identifier)) 0024-1164. There is no evidence of a direct connection to the gladius; it is therefore assumed that the fins were inserted into the mantle. === Arms === ''Muensterella'' shows 4 pairs of visible arm bases in at least 2 specimens preserving soft tissue from Solnhofen; this points to ''Muensterella'' having 8 [arms](/source/Cephalopod_limb) of equal length, as is expected for octopodiformes. The very tips of the arms appear to be missing, but ''Muensterella'' still shows some of the shortest known arms among Mesozoic gladius-bearing cephalopods. The presence of tentacles is unlikely and cannot be confirmed by the fossil material. A short interbrachial web possibly extends for {{convert|1|cm|abbr=on}} between the arms. The imprints of [suckers](/source/Cephalopod_limb) are only known from a single specimen, MC-21. The circular suckers are arranged in a single row proximally, but they make a zigzag pattern the closer they get to the distal ends of the arms. Closer to the base, the suckers are larger in size, the largest being 5 mm wide, while at the end they grow to only 1 mm in width. Hooks or cirri are unknown. left|thumb|Fossilized remains of the digestive system of ''Muensterella scutellaris'' === Internal anatomy === A few specimens show different parts of the internal anatomy of ''Muensterella'', including the holotype of ''M. spinosa,'' which shows the imprint of an [ink sac](/source/ink_sac), the organ typical of cephalopods used to spray [ink](/source/ink) at predators to enable escape. A specimen of ''M. scutellaris'' preserves parts of the [digestive system](/source/digestive_system); the preserved remains resemble a swollen, meandering tube which, in contrast to the surrounding mantle, is longitudinally striated. It might either represent the remains of a [crop](/source/Crop_(anatomy)), a temporary food-storage organ in the digestive system of cephalopods where captured prey is stored and softened after passing through the [oesophagus](/source/oesophagus), or the [intestine](/source/Gastrointestinal_tract). == Paleobiology and paleoecology == ''Muensterella'' is a small [octopodiforme](/source/Octopodiformes), with ''M. scutellaris'' reaching a maximum gladius length of ~{{convert|170|mm|abbr=on}} and ''M. spinosa'' ~{{convert|70|mm|abbr=on}}. The single known specimen of ''M. jillae'' is incomplete, but the patella alone is already longer than the complete gladius of ''M. scutellaris'', with a length of ~{{convert|220|mm|abbr=on}}. Fossil remains of ''Muensterella'' have exclusively been found in shallow water deposits such as the [Kimmeridgian](/source/Kimmeridgian) to [Tithonian](/source/Tithonian) [Solnhofen Limestone](/source/Solnhofen_Limestone), where both ''M. scutellaris'' and ''M. spinosa'' originate from. The paleogeographic region known as the Solnhofen [Archipelago](/source/Archipelago) consisted of a series of islands and [reef](/source/reef)s which were part of a warm, tropical, shallow [epicontinental sea](/source/epicontinental_sea) at the northern edge of the [Tethys Ocean](/source/Tethys_Ocean). The limestone deposited in this region preserved one of the most speciose [palaeobiotas](/source/Paleobiota_of_the_Solnhofen_Limestone) on earth, showing a vast diversity of [fish](/source/fish), [marine reptile](/source/marine_reptile)s, [crustaceans](/source/crustaceans)s, [gastropod](/source/gastropod)s and [cephalopod](/source/cephalopod)s, such as ''Muensterella'' itself. The fossils themselves were deposited at the bottom of [anoxic basins](/source/Anoxic_waters) on the seafloor, often referred to as [lagoon](/source/lagoon)s, which allowed for the exceptional preservation of details like their soft tissue. This means however that they were swept into the basins from surrounding environments, and did not inhabit these locations (allochthonous). ''Muensterella'' probably inhabited the surrounding [coral](/source/Coral_reef) and [sponge reef](/source/sponge_reef)s.Arratia Fuentes, Gloria; Schultze, Hans-Peter; Tischlinger, Helmut; Viohl, Günter, eds. (2015). ''Solnhofen: ein Fenster in die Jurazeit''. München: Verlag Dr. Friedrich Pfeil. {{ISBN|978-3-89937-195-6}}. {{OCLC|929457413}} ''Muensterella'' was presumably a [necto-benthic](/source/Benthic_zone) animal, meaning it stayed close to the sea floor while retaining the ability to move freely through the [water column](/source/water_column) as it most likely represented a negatively buoyant shallow water [jet swimmer](/source/Aquatic_locomotion), which propelled itself through the water column using the water pushed out of the [siphon](/source/Siphon_(mollusc)), similar to [cuttlefish](/source/cuttlefish) and [bobtail squid](/source/bobtail_squid). These are probably closest living analogues to the general [ecological role](/source/Ecological_niche) of ''Muensterella''; both cuttlefish and bobtail squids are [ambush predator](/source/ambush_predator)s that primarily feed on crustaceans and small fish using their ability to [change color](/source/Chromatophore) to camouflage themselves, and also to [avoid becoming prey](/source/Anti-predator_adaptation) themselves. While this cannot be proven by the fossil record it is probable that ''Muensterella'' shared the typical [intelligence](/source/Cephalopod_intelligence) and camouflaging abilities of both cuttlefish and their closer relatives, [octopus](/source/octopus). == Distribution and species == The type species of ''Muensterella'', ''M. scutellaris,'' is found in the [Solnhofen Lithographic limestones](/source/Solnhofen_Limestone) of [Bavaria](/source/Bavaria), [Germany](/source/Germany), a series of several different very similar fossil localities. ''M. scutellaris'' has been found in the [Kimmeridgian](/source/Kimmeridgian) to [Tithonian](/source/Tithonian) [Geisental Formation](/source/Geisental_Formation) and the Tithonian [Painten Formation](/source/Painten_Formation), [Altmühltal Formation](/source/Solnhofen_Limestone) and [Mörnsheim Formation](/source/M%C3%B6rnsheim_Formation). Muensterella is so far absent from other Late Jurassic lithographic limestones such as [Nusplingen](/source/Nusplingen_Limestone) or [Cerin](/source/Cerin_Lagerst%C3%A4tte). The second species from the Solnhofen Archipelago, ''M. spinosa,'' is known only by one specimen (BSPG 1964XXII) from the [Mörnsheim Formation](/source/M%C3%B6rnsheim_Formation). It is [distinguished](/source/Autapomorphy) from ''M. scutellaris'' by the prominent spines on the dorsal surface of the patella and the posteriorly shifted apex of the patella. It has been discussed whether or not this species could represent an example of [sexual dimorphism](/source/sexual_dimorphism), but that has been deemed unlikely.{{Clarify|date=January 2026}} Another specimen, referred to as ''Muensterella sp''., is known from the Tithonian [Ameghino Formation](/source/Ameghino_Formation) (=[Nordenskjöld Formation](/source/Nordenskj%C3%B6ld_Formation)) of Antarctica; it is too incomplete to [diagnose](/source/Species_diagnosis) properly as a distinct species.Doyle, Peter. (1991). Teuthid Cephalopods from the Upper Jurassic of Antarctica. Palaeontology. 34. 169-178 An extraordinarily well-preserved specimen of what has been tentatively referred to as ''Muensterella [aff.](/source/aff.) scutellaris'' hails from a [Cenomanian](/source/Cenomanian) to [Turonian](/source/Turonian) [black shale](/source/black_shale) [succession](/source/Succession_(geology)) near Misburg, [Hannover](/source/Hanover). The specimen is very similar to the type species but distinguished by the shape of its patella, which is more slender than that of ''M. scutellaris''. The specimen has not been named as it belongs to a [private collection](/source/Fossil_collecting). The largest species of ''Muensterella'', ''M. jillae,'' is known by a singular incomplete specimen (NPL81150) originating from the middle [Turonian](/source/Turonian) [South Bosque Formation](/source/South_Bosque_Formation). ''M. jillae'' is very similar in its gladius shape to the type species, but the apex of its conus is more posterior; the complete gladius might have been {{convert|399|mm|abbr=on}} long. ''"Muensterella" tonii'' from the [late Albian](/source/Albian) [Toolebuc Formation](/source/Toolebuc_Formation) of [Queensland](/source/Queensland), [Australia](/source/Australia), has been reassigned to the genus ''[Enchoteuthis](/source/Enchoteuthis)''. == Evolutionary significance and phylogeny == [Muensterelloids](/source/Muensterelloidea) have traditionally been identified as being closely related to [teudopseids](/source/Teudopseina), a clade that includes the majority of known gladius-bearing Mesozoic cephalopods. In 1990 Engeser for the first time considered the relationship of the Muensterelloidea to the [Octopoda](/source/Octopus), which includes all modern [cirrate](/source/Cirrina) and [incirrate octopus](/source/Incirrata). However, a 2015 [phylogenetic analysis](/source/phylogenetic_analysis) conducted by Sutton, which only included one Muensterelloid, ''Muensterella'' itself, found it to be more closely related to [trachyteuthid](/source/Trachyteuthididae)s, with the squid-like [plesioteuthid](/source/Plesioteuthididae)s grouped closer to octopodes.Sutton, Mark; Perales-Raya, Catalina; Gilbert, Isabel (2016). "A phylogeny of fossil and living neocoleoid cephalopods". ''Cladistics''. '''32''' (3): 297–307. [doi](/source/Doi_(identifier)):10.1111/cla.12131. [hdl](/source/Hdl_(identifier)):10261/324645. [ISSN](/source/ISSN_(identifier)) 1096-0031. This relationship has since been deemed unlikely; instead, Fuchs et al. (2020) found Muensterelloids to be sister taxa to the [Palaeololiginidae](/source/Palaeololiginidae). The very same analysis finds Muensterelloids, which have never been found to be [paraphyletic](/source/paraphyletic), to consist of two main clades, the [Patelloctopodidae](/source/Patelloctopodidae) and the ‘Muensterella–[Enchoteuthidae](/source/Enchoteuthis) clade’. The unusual morphology of the gladius in ''[Patelloctopus ilgi](/source/Patelloctopus)'' links the morphology seen in teudopseids like Muensterella and [crown](/source/Crown_group) cirrates and incirrates. It is possible that the patelloctopodid clade includes the [last common ancestor](/source/last_common_ancestor) of cirrate and incirrate octopods, whereas the "Muensterella-Enchoteuthidae" clade likely became extinct during the [Late Cretaceous](/source/Late_Cretaceous). Presumably, these two clades split in the middle-late [Toarcian](/source/Toarcian), which would make it congruent with the minimum divergence date calculated by Tanner et al. (2017) using a [molecular clock](/source/molecular_clock) analysis. The results of the 2020 analysis show ''Muensterella'' as a grade leading up to the [Enchoteuthidae](/source/Enchoteuthidae):{{clade| style=font-size: 90%; line-height:100% |grouplabel1={{Clade labels|label1='[Muensterellidae](/source/Muensterellidae)'|top1=30%|color1=pink}} |label1='''[Vampyromorphida](/source/Vampyromorphida)''' |1={{clade |1={{clade |1=''[Teudopsis acuta](/source/Teudopsis)'' |2={{clade |1=''[Palaeololigo albersdoerferi](/source/Palaeololigo)'' |label2=[Muensterelloidea](/source/Muensterelloidea) |2={{clade |1=''[Celaenoteuthis incerta](/source/Celaenoteuthis)''|style1=background-color:#fff5f5|barbegin1=pink |2={{clade |1=''[Engeseriteuthis arcuatus](/source/Engeseriteuthis)''|style1=background-color:#fff5f5|bar1=pink |2={{clade |1={{clade |1=''[Listroteuthis conica](/source/Listroteuthis)''|style1=background-color:#fff5f5|bar1=pink |2={{clade |1='''''Muensterella scutellaris'''''|style1=background-color:#fff5f5|bar1=pink |2={{clade |1='''''Muensterella spinosa'''''|style1=background-color:#fff5f5|bar1=pink |2={{clade |1='''''Muensterella jillae'''''|style1=background-color:#fff5f5|bar1=pink |2={{clade |1='''''Muensterella sp'''''.|style1=background-color:#fff5f5|barend1=pink |label2=[Enchoteuthidae](/source/Enchoteuthidae) |2={{clade |1=''[Niobrarateuthis bonneri](/source/Niobrarateuthis)'' |2={{clade |1=''[Enchoteuthis melanae](/source/Enchoteuthis)'' |2={{clade |1=''[Enchoteuthis cobbani](/source/Enchoteuthis)'' |2=''[Enchoteuthis tonii](/source/Enchoteuthis)'' }} }} }} }} }} }} }} }} |2={{clade |1=''[Tyrionella fauseri](/source/Tyrionella)''|style1=background-color:#fff5f5|barbegin1=pink |2={{clade |1=''[Etchesia martilli](/source/Etchesia)''|style1=background-color:#fff5f5|bar1=pink |2={{clade |1=''[Muensterellina johnjagti](/source/Muensterellina)''|style1=background-color:#fff5f5|barend1=pink |2={{clade|state2=dashed |label1=[Patelloctopodidae](/source/Patelloctopodidae) |1={{clade |1=''[Pearceiteuthis buyi](/source/Pearceiteuthis)'' |2=''[Patelloctopus ilgi](/source/Patelloctopus)'' }} |label2=[Palaeoctopodidae](/source/Palaeoctopodidae) |sublabel2=(Relationship with Patelloctopodidae is assumed only) |2={{clade |1={{clade |1=''[Keuppia hyperbolaris](/source/Keuppia)'' |2=''[Keuppia levante](/source/Keuppia)'' }} |2=''[Palaeoctopus newboldi](/source/Palaeoctopus)'' |3=''[Styletoctopus annae](/source/Styletoctopus)'' }} }} }} }} }} }} }} }} }} }} }} }} == References == {{Reflist}} {{Taxonbar|from=Q29088204}} Category:Prehistoric cephalopod genera --- Adapted from the Wikipedia article [Muensterella](https://en.wikipedia.org/wiki/Muensterella) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Muensterella?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.