taxonID	type	description	language	source
E970D274FFDEFFD3FCDEF981FDB6FE10.taxon	description	In the Reşiţa- Moldova Nouă area, the onset of the Lower Cretaceous (Bucur, 1997) starts with the Lower Berriasian, represented by the Marila Limestones, and the Upper Berriasian-Lower Valanginian by the Crivina Marls, both formations corresponding to basinal deposits 1 Aix-Marseille University, Place Victor Hugo. 13331 Marseille Cedex 03, France, jean-pierre. masse @ hotmail. com 3 2 Babeş- Bolyai University, Department of Geology and Center for integrated geological studies, Str. M. Kogalniceanu 1, 400084 Cluj-Napoca, Romania. with calpionellids and ammonites. The Valea Lindinei Limestones (upper Valanginian-Hauterivian), make the transition from the basinal to the overlying shallow carbonate platform deposits. The corresponding Urgonian beds (Fig. 2 a) includes the Valea Nerei Limestone Member, which consists of bioclastic limestone, sometimes with corals, chaetetids and rudists, i. e. Pachytraga carpathica Masse et al. (Masse et al., 2023) and Matheronia dacica sp. nov. The micropaleontogical assemblage of orbitolinid foraminifera and dasycladale algae: Moulladella jourdanensis, Cribellopsis thieuloyi and Salpingoporella muehlbergii, documents the Lower Barremian (Bucur, 1997). The overlying Valea Minişului Limestone Formation (Fig. 2 a) consists of bioclastic limestones, with marly intercalations. The orbitolinid association is twofold: the lower assemblage consists of Paracoskinolina maynci, Montseciella? arabica, Palorbitolina lenticularis and Praeorbitolina cormyi, of late Barremian – early Aptian age, these beds yield Matheronia nerae sp. nov. and Matheronia carinata sp. nov. The content of the upper assemblage, Mesorbitolina parva, Mesorbitolina texana and radiolitids, indicates a late Aptian age; the overlying Golumbu sandstones may belong to the “ Clansayesian ” (Bucur, 1997). In the Pădurea Craiului Mountains, the Lower Cretaceous deposits start with bauxitic rocks, followed by micritic lacustrine-paludary limestones, i. e. the Dobreşti Member of the Blid Formation, of Berriasian-Hauterivian pro parte age (Bucur, 2000; Cociuba, 2000) (Fig. 2 b). The upper member of the Blid Formation, i. e. the Coposeni Member, consists of micritic-fenestral and bioclastic limestone, with rudists including Matheronia dacica sp. nov. Foraminifera and calcareous algae Pfenderina globosa, Moulladella jourdanensis, Salpingoporella genevensis, S. melitae, S. muehlbergii, document an early Barremian age. In its upper part, the Coposeni Member contains Palorbitolina lenticularis, so that the overall age of the Coposeni deposits is Hauterivian pro parte – Barremian. New species of the Lower Cretaceous genus Matheronia Munier-Chalmas (Bivalve Hippuritida) in Romania The succession continues with the Ecleja Formation, its carbonate upper part, the Bobdei Valley Limestone Member contains Palorbitolina lenticularis, Akcaya capitata, Paracoskinolina maynci and Salpingoporella popgrigorei, an association that suggests a possible early Aptian age. The Ecleja formation is covered by the Măgurii Valley Limestone Formation with rudists including Matheronia silvaeregis sp. nov., Lovetchenia, Horiopleura and caprinids. The associated Orbitolinidae: Palorbitolina lenticularis, Orbitolinopsis cuvillieri, O. kiliani, O. buccifer, and O. pygmaea, document an early Aptian age (Cociuba, 2000). This dating is corroborated by the age of the overlying marls, characterized by Dufrenoya, a late early Aptian ammonite.	en	MASSE, JEAN-PIERRE, FENERCI-MASSE, MUKERREM, BUCUR, IOAN I. (2024): New Species Of The Lower Cretaceous Genus Matheronia Munier-Chalmas (Bivalve Hippuritida) In Romania. Acta Palaeontologica Romaniae 20 (1): 3-15, DOI: 10.35463/j.apr.2024.01.01, URL: http://dx.doi.org/10.35463/j.apr.2024.01.01
E970D274FFDDFFD4FF79FBB3FAEBFA35.taxon	materials_examined	Type species Caprotina virginiae Gras, 1852 Generic characters of the genus Matheronia and comments on the subfamily Matheroninae The shell is attached by the LV, mostly matheroniform sensu Masse (2002), i. e. spirogyrate. RV uncoiled with growth lines concentric to the apex. On antero-posterior transverse sections the RV pm is a crest, am a bulge. LV myophores being on inner shell wall. The striking difference with the other Requieniinae, e. g. Requienia, is the existence of a RV posterior myophoral plate, lacking in Matheronia, as established by Douvillé (1915). The foregoing shows that among the Requieniidae the generic identification of Matheronia requires the presence of both valves, especially the RV which bears the diagnostic myophoral characters; an antero-posterior section showing the posterior myophoral crest and the anterior myophoral bulge is necessary and sufficient for this purpose.	en	MASSE, JEAN-PIERRE, FENERCI-MASSE, MUKERREM, BUCUR, IOAN I. (2024): New Species Of The Lower Cretaceous Genus Matheronia Munier-Chalmas (Bivalve Hippuritida) In Romania. Acta Palaeontologica Romaniae 20 (1): 3-15, DOI: 10.35463/j.apr.2024.01.01, URL: http://dx.doi.org/10.35463/j.apr.2024.01.01
E970D274FFDDFFD4FF79FBB3FAEBFA35.taxon	diagnosis	Emended diagnosis Shell attached by the LV, mostly matheroniform, i. e. spirogyrate, with a short beak. RV uncoiled with growth lines concentric to the apex, The RV pm is a crest, am a bulge. LV myophores being on inner shell wall. Radial bands usually absent or inconspicuous. Several additional characters The presence of a well-defined LV anterior tooth socket was considered by Paquier (1903) as a diagnostic character of M atheronia, a point of view shared by Mongin (1971), but not retained by Douvillé (1915) and most of the subsequent workers. The existence of an additional tooth (PII) was noticed by Douvillé (1915) in the LV cardinal area of Matheronia virginiae, but this feature, recorded in some other rudists, is considered to have a negligeable taxonomic value. The dorso-ventral length of the RV anterior and posterior myophores is distinct: ma being longer than mp (Douvillé, 1887; Paquier, 1903). Radial bands (pro siphonal bands of Douvillé, 1915) appear to be lacking in most of Matheronia species, whereas they are present in Requienia species (Douvillé, 1915, 1918; Mongin & Trouvé, 1953; Mongin, 1971). Nevertheless, radial bands are somewhat crudely outlined in Matheronia baksanensis and M. aptiensis, but not frankly sketched in Requienia migliorinii, even if the generic name of this taxon cannot be ascertained (Masse, 2002). There is consensus among palaeontologist to recognize the short beak of LV and the absence of coiling of RV, two correlated characters, as typical attributes of Matheronia. But this trait does not match the morphology of the Valanginian Matheronia? taurica Yanin (1985), an atypical form with a LV having a corkscrew shape, a RV with a raised dorsal margin and a myophoral organisation close to that of Hypelasma. By contrast the large size and thick shell of Matheronia invoked by Paquier (1903), Douvillé (1935) and Dechaseaux et al. (1969) as an attribute of the genus, cannot be retained, e. g. Matheronia aptiensis has a modest size and a limited shell thickness, some of our new species described herein belong to this category. The definition of the subfamily Matheroniinae (in Skelton, 2013; after Scott et al., 2010) states that “ the LV myophores are as expanded plates on the valve wall ”: a character which applies to Lovetchenia Masse but not to Matheronia, and the “ RV pm extends from the cardinal platform ” (see also Dechaseaux et al., 1969) a character lacking for instance in Matheronia virginiae. As noticed earlier (Masse, 2002) the shell morphology of Matheronia is not always “ matheroniform ”, for instance it is “ requieniform ” in Matheronia? taurica and somewhat “ toucasiform ” in Matheronia baksanensis. The foregoing shows that the definition of the subfamily Matheroniinae has to be reappraised. In the following we compare the Romanian material with the classical Urgonian species of SE France. Matheronia aptiensis, M. munieri and M. virginiae, here illustrated to document some of their generic attributes (Fig. 3). Comparisons are based on the recent revision of the corresponding species collections stored in the Urgonia Museum of Orgon. The age of this reference fauna is Barremian (Frau et al., 2018; Masse et al., 2020). By contrast with the Urgonian species from SE France represented by well-preserved whole shells, the Romanian forms, but one, are represented by variously oriented sections; we have selected the rather rare, bivalve, antero-posterior sections exhibiting the RV myophores, but such material makes uncertain the recognition of the radial bands. Hence the vast majority of sections represent left valves, which cannot be safely assigned either to Requienia or Matheronia and are just identified as “ requieniids ”, excluding Toucasia with a myophoral crest or ridge on LV. Specific attributes of Matheronia combine the following traits: size (Dap and Dvd), transverse cross sectional shell outline, presence or absence of a ventral carina, development of the LV shell lamellar surface, usually more important on the anterior side, and shape of the RV. The use of Dap as a size parameter, is a standard for requieniids, but Dvd does not fit the common use of this parameter. The usual dimensional approach for requieniids deals with the W / L ratio (e. g. Masse et al., 1998) in which W is the width, equivalent to Dap, L being the distance between the dorsal and ventral shell margin, i. e. Ddv sensu stricto, acquired in the plane of the RV. In the following Ddv does not conform this definition but corresponds to the distance between the ventral margin of the LV and the plane of the RV, hence the smeasurements of Dap and Dvd are tranversally orthogonal. This method was introduced to acknowledge a quantitative approach based on transverse sections rather than well-preserved entire specimens.	en	MASSE, JEAN-PIERRE, FENERCI-MASSE, MUKERREM, BUCUR, IOAN I. (2024): New Species Of The Lower Cretaceous Genus Matheronia Munier-Chalmas (Bivalve Hippuritida) In Romania. Acta Palaeontologica Romaniae 20 (1): 3-15, DOI: 10.35463/j.apr.2024.01.01, URL: http://dx.doi.org/10.35463/j.apr.2024.01.01
E970D274FFDAFFD4FC3EF9AAFB44F9D3.taxon	description	Figure 4 a, b	en	MASSE, JEAN-PIERRE, FENERCI-MASSE, MUKERREM, BUCUR, IOAN I. (2024): New Species Of The Lower Cretaceous Genus Matheronia Munier-Chalmas (Bivalve Hippuritida) In Romania. Acta Palaeontologica Romaniae 20 (1): 3-15, DOI: 10.35463/j.apr.2024.01.01, URL: http://dx.doi.org/10.35463/j.apr.2024.01.01
E970D274FFDBFFD5FC3AFC38FA7EFBBF.taxon	description	Figure 5 a-e Derivation of name. From its geographical origin Valea	en	MASSE, JEAN-PIERRE, FENERCI-MASSE, MUKERREM, BUCUR, IOAN I. (2024): New Species Of The Lower Cretaceous Genus Matheronia Munier-Chalmas (Bivalve Hippuritida) In Romania. Acta Palaeontologica Romaniae 20 (1): 3-15, DOI: 10.35463/j.apr.2024.01.01, URL: http://dx.doi.org/10.35463/j.apr.2024.01.01
E970D274FFD8FFD6FC2BFA7AFB46F9A0.taxon	description	Figure 6 a-d	en	MASSE, JEAN-PIERRE, FENERCI-MASSE, MUKERREM, BUCUR, IOAN I. (2024): New Species Of The Lower Cretaceous Genus Matheronia Munier-Chalmas (Bivalve Hippuritida) In Romania. Acta Palaeontologica Romaniae 20 (1): 3-15, DOI: 10.35463/j.apr.2024.01.01, URL: http://dx.doi.org/10.35463/j.apr.2024.01.01
E970D274FFD9FFD7FF79FAC5FB76F89D.taxon	diagnosis	Diagnosis. Matheronia with a medium size, toucasiform, i. e. with an antero-posterior compression, LV anterior side concave, with an acute ventral carina. Comparisons. The size of Matheronia carinata sp. nov. is in the range of that of M. aptiensis, i. e. smaller than M. munieri and M. virginiae. It also differs from the West European species by a more concave LV anterior side and a more acute carina. The radial bands of M. carinata sp. nov. are inconspicuous, hence different from that of Matheronia baksanensis and M. aptiensis, somewhat outlined. Due to its antero-posterior compression coupled with the acute carina, M. carinata sp. nov. looks like Toucasia, it is the only toucasiform Matheronia species known so far. Dap is larger than Ddv, two dimensions nearly equivalent in M. aptiensis.	en	MASSE, JEAN-PIERRE, FENERCI-MASSE, MUKERREM, BUCUR, IOAN I. (2024): New Species Of The Lower Cretaceous Genus Matheronia Munier-Chalmas (Bivalve Hippuritida) In Romania. Acta Palaeontologica Romaniae 20 (1): 3-15, DOI: 10.35463/j.apr.2024.01.01, URL: http://dx.doi.org/10.35463/j.apr.2024.01.01
E970D274FFD9FFD7FC57F8B4FA7EF85A.taxon	description	Figure 7 a, b 2023 Requienia sp. 1, Masse et al., fig. 2 B 1 - 2. Derivation of name. From its geographical origin	en	MASSE, JEAN-PIERRE, FENERCI-MASSE, MUKERREM, BUCUR, IOAN I. (2024): New Species Of The Lower Cretaceous Genus Matheronia Munier-Chalmas (Bivalve Hippuritida) In Romania. Acta Palaeontologica Romaniae 20 (1): 3-15, DOI: 10.35463/j.apr.2024.01.01, URL: http://dx.doi.org/10.35463/j.apr.2024.01.01
