The Mesones Group is a Cambrian geologic group in Spain. It preserves numerous soft-bodied and hard-shelled taxa such as echinoderms and trilobites. It is often stated to contain the Mansilla, Murero and Valdemiedes Formations, however just as often the Murero Formation is used to refer to the entire group, with the main lagerstätte being placed interchangeably in Mansilla, the "broader" Murero or occasionally a broader Valdemiedes.
Paleobiota
PaleobiotaGenusSpeciesHigher taxonNotesImagesCtenoimbricataC. spinosaEchinodermataMost basal known echinoderm, completely bilateral unlike modern formsDibrachicystisD. purujoensisRhombiferaBears unusual appendages, suggesting blastozoan and crinoid "arms" come from the same sourceVizcainoiaV. moncaiensisRhombiferaFormerly placed inside EocystitesProtorophusP. hispanicusEdrioasteroideaEarliest known member of IsorophidaeGraciacystisG. ambiguaCinctaBasal cinctan, known from over a hundred specimens of different agesAragocystitesA. belliEdrioasteroideaA relatively basal edrioasteroid, related to CambrasterCambrasterC. tastudorumEdrioasteroideaFirst edrioasteroid found in SpainProtocinctusP. mansillaensisCinctaEarliest known cinctan genusGogiaG. parsleyiEocrinoideaOldest records of the genus from GondwanaRhopalocystis??R. mesonesensisEocrinoideaUnclear whether it even belongs to the genusGyrocystisG. platessa, G. erecta, G. testudiformis, G. badulesiensis?CinctaA relatively diverse cinctanCaryosyntripsC. cf. camurusPanarthropodaFrontal appendages (the only part known) formerly identified as the lobopodian "Mureropodia apae"TuzoiaT. isuelaensisHymenocarinaOnly known from carapaces, alongside an indeterminate euarthropodWimanicharionW. matthewiBradoriidaAlso known from Sweden and CanadaNaraoiaN. sp.NaraoiidaeSome of the first evidence of Naraoia in EuropePeronopsisP. ferox, P. insignis, P. longinquaAgnostidaAn incredibly common agnostid from all over the worldCondylopygeC. cruzensisCondylopygidaeMegagnostusM. spAgnostidaLess common than Peronopsis, makes up fewer of the enrolled specimens in MureroBailiaspisB. tuberculataConocoryphidaeUnclear whether any Mesones specimens belong to the speciesCHIRIVELLA MARTORELL, J. B., LIÑÁN, E., DIEZ ÁLVAREZ, M. E., & GOZALO, R. 2017. Bailiaspis (Trilobita) with English affinities from the Mansilla Formation (Cambrian Series 3 of the Iberian Chains; NE Spain). [Bailiaspis (Trilobita) de afi nidad inglesa en la Formación Mansilla (Serie 3 del Cámbrico de la Cadena Ibérica; NE España)]. Spanish Journal of Palaeontology, 32 (1), 17 - 26.BailiellaB. tenucinctaConocoryphidaeA blind trilobiteConocorypheC. hebertiConocoryphidaeAn eyeless trilobite.CornucorypheC. schirmiConocoryphidaeAn unusual trilobite with a horn in the middle of its headEccaparadoxidesE. pradoanus E. mediterraneusParadoxididaeVery abundant in Murero, had unique specialisations for enrolment and shows unusual variabilityPardailhaniaP. hispida, P. multispinosa, P. sdzuyiSolenopleuridaeUsed for stratigraphy in MureroSolenopleuropsisS. marginata, S. thoraliSolenopleuridaeExhibits circular enrolment alongside PardailhaniaDinesusD. truyolsiDinesidaeAluevaA. undulataEllipsocephalidaeExhibits paedomorphosisWronascolex??W. spPalaeoscolecidaFormerly placed within PalaeoscolexMarocellaM. morenensisHelcionelloideaFound in other localities across the worldTrematobolusT. simplexObolidaeSynonymous with the purported "bivalve" LamellodontaBrahimorthisB. alvaroiBrahimorthidae (Orthida)Relatively underived member of the genusNisusiaN. spKutorginataSerpulidae indet.UnapplicableSabellidaEncrusted on shellsLeptomitusL. lineatus, L. conicusProtomonaxonidaL. lineatus specimens may not belong to the speciesCrumillospongiaC. mureroensisProtomonaxonidaBears larger pores than other members of the genusEiffelia??E. spProtomonaxonidaOnly known from six-rayed spiculesChancelloriaC. spChancelloriidaeAlso only known from spiculesPsammosphaeraP. spAstrorhizida (Foraminifera)Mainly encrusted on shells
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