Back
Muderongia neocomica
Muderongia neocomica (Gocht, 1957) Lentin and Williams, 1993
Originally Wetzeliella?, subsequently Phoberocysta, thirdly (and now) Muderongia.
This species was emended, as Phoberocysta neocomica by Helby, 1987.
The species was listed in synonymy under Muderongia tomaszowensis Alberti, 1961, by Monteil, 1991, who considered Phoberocysta Millioud, 1969, to be a tax. jr. synonym of Muderongia. However, Phoberocysta (as Muderongia) neocomica must be retained as the tax. sr. synonym. Monteil in an Errata sheet accompanying Monteil, 1991, acknowledged this. Monteil, 1991, emended the diagnosis of Muderongia tomaszowensis. In the Errata sheet Monteil gave the citation: "Muderongia neocomica Gocht 1957 comb. nov. and emend." This combination is not validly published since Monteil did not fully reference the basionym and the Errata sheet does not constitute effective publication.
Monteil, 1991, also listed in synonymy with Muderongia tomaszowensis the following taxa: Phoberocysta neocomica ssp. circulata (Gocht, 1957) Lentin and Williams, 1973; Phoberocysta neocomica ssp. cruciformis (Gocht, 1957) Lentin and Williams, 1973; and Phoberocysta neocomica ssp. dedecosa (Gocht, 1957) Lentin and Williams, 1973. Lentin and Williams, 1993, assumed that Monteil, 1991, intended to treat all three subspecies as tax. jr. synonyms of the autonym Phoberocysta neocomica ssp. neocomica.
Holotype: Gocht, 1957, pl.19, fig.1; text-fig.7
Locus typicus: Ruehlertwist, Emsland, NW Germany
Stratum typicum: Hauterivian
Translation Gocht, 1957: LPP
Original description: Gocht 1957, p. 172-176: Wetzeliella ?neocomica.
Diagnosis: Shell flattened, extremely variable in shape, generally more or less 4-5 sided, delicate. Closed edge rare; Shell all around mostly developing into bilayered and exteriorly closed projections, which may be located at several levels, but which are essentially limited to the region of the outer margin. Among them, an apical horn, two lateral horns, and an antapical horn smay often be clearly distinguished. Projections and horns often provided with pointed, blunt or trumpet shaped, flat protruberances or processes, which almost exclusively stand along the outline, and rarely on the surface. On the front and back sides projections or processes are sporadic. Along the margins of the apical and antapical horns, the protruberancesare are often arranged alternatively. Lateral horns mostly slightly squat, broad-based, sometimes slightly bent, giving rise to a slightly V-shaped cross-section.
Projections and processes may be considerably reduced or extremely enlarged, as well as the horns, which may also partly be missing or be unrecognizable as such.
Exceptionally, denticulate ridges or idications of a transverse furrow occur on the shell.
Inner body delicate, with a more or less oval outline.
Emended description: Helby, 1987, p. 310-313: Phoberocysta neocomica
Proximochorate cyst, outline rhomboidal with a prominent apical horn, cingular horns, left antapical horn and a periphragm bulge of variable size constituting a right antapical horn. Cingular horns variably developed, usually expressed as stout lateral bosses. Each cingular horn consisting of parts of 2 modified paraplates from each of the precingular and postcingular series and a cingular paraplate (2c) on the left and 2 cingular paraplates (4c and 5c) on the right.
Posterior surface of the lateral tip of the horns, comprising the lateral extension of the postcingular paraplates, often inclined posteriorly. Lateral edges of the cingular horns slope anteriorly towards the cyst, although parasutural ridges give it a distinctive notched appearance, often exaggerated by development of substantial gonal spines. Left antapical horn prominent, usually rounded at the distal end. Cyst 2-layered, cornucavate, but wall layers closely appressed over most of the dorsal and ventral surfaces. Endocyst rhomboidal with small protrusions at horn bases apart from the right antapical horn. Periphragm varying from smooth to finely granulate, scabrate and occasionally perforate. Periphragm bearing a variety of spines and spinules. Large, solid, capitate spines (tapered from a very broad base, and up to 15 Ám long), generally with small spinules.
Spines generally gonal and parasutural and only occasionally intratabular. Spinules (0.5-1Ám high) concentrated at the distal extremities of large spines and horns (particularly the apical and antapical horns) or may occur as scattered intratabular groups, or may be aligned parasuturally. Endophragm usually granulate. Paratabulation indicated by archeopyle, by the location of gonal and intergonal spines and occasionally by less distinct parasutural features such as delicate differentiation of the periphragm (scabration). Paratabulation formula interpreted as 4", 0a, 6"", 6c(?), 6""", 1p, 1"""" (fig.15). Archeopyle apical, type [tA], principle archeopyle suture zigzag with parasulcal notch set off to left side. Paracingulum transverse feature across dorsal surface onto paracingular horns where it is evident as a distinct concavity (exaggerated by gonal spine development) at the lateral edge of the horns. Parasulcus sinous, offset from a midventral position on the hypocyst to a left ventral position on the epicyst. Parasulcal plates not well defined.
Emended diagnosis: Monteil, 1991, p. 477: Muderongia tomaszowensis
Cysts proximate to proximochorate, compressed dorsoventrally, two-layered, cornucavate to delphicavate or circumcavate. Pericyst ceratioid, symmetrical, with 4 prominent horns: 1 apical (axial, type AP I); 2 subequal lateral (axial, type L I), indented; 1 antapical (axial, type ATP I). Left lateral horn may be slightly more reduced than the right one. Horns normal with distal extremities closed and rounded; proximal extremities narrow, except for the antapical horn which may be wider A small rounded bulge can be present in right antapical position (Pl. 3, figs. 1, 2). Endocyst oval to rhombic. Periphragm thin, psilate to scabrate; periphragm may be ornamented by verrucae or processes (stages I to IV). Endophragm thin, psilate to granulate Archeopyle apical, type (4A), with angular margin. Parasulcal notch marked. Operculum free. Paratabulation indicated by archeopyle, by low parasutural ridges or septa, and more or less clearly expressed by distribution and type of processes (stages I to IV), when those are present. Occasionally, periphragm showing penitabular verrucae. Formula:?pr, 4", 0a, 6", 6c, 6""", 1p, 1"""". Pericingulum marked by indentation of lateral horns and by parallel transverse structures. Perisulcus marked by parasulcal notch offset. Parasulcal area not observed.
Dimensions of the holotype (with operculum): 140 Ám x 112 Ám (overall L x I).
Originally Wetzeliella?, subsequently Phoberocysta, thirdly (and now) Muderongia.
This species was emended, as Phoberocysta neocomica by Helby, 1987.
The species was listed in synonymy under Muderongia tomaszowensis Alberti, 1961, by Monteil, 1991, who considered Phoberocysta Millioud, 1969, to be a tax. jr. synonym of Muderongia. However, Phoberocysta (as Muderongia) neocomica must be retained as the tax. sr. synonym. Monteil in an Errata sheet accompanying Monteil, 1991, acknowledged this. Monteil, 1991, emended the diagnosis of Muderongia tomaszowensis. In the Errata sheet Monteil gave the citation: "Muderongia neocomica Gocht 1957 comb. nov. and emend." This combination is not validly published since Monteil did not fully reference the basionym and the Errata sheet does not constitute effective publication.
Monteil, 1991, also listed in synonymy with Muderongia tomaszowensis the following taxa: Phoberocysta neocomica ssp. circulata (Gocht, 1957) Lentin and Williams, 1973; Phoberocysta neocomica ssp. cruciformis (Gocht, 1957) Lentin and Williams, 1973; and Phoberocysta neocomica ssp. dedecosa (Gocht, 1957) Lentin and Williams, 1973. Lentin and Williams, 1993, assumed that Monteil, 1991, intended to treat all three subspecies as tax. jr. synonyms of the autonym Phoberocysta neocomica ssp. neocomica.
Holotype: Gocht, 1957, pl.19, fig.1; text-fig.7
Locus typicus: Ruehlertwist, Emsland, NW Germany
Stratum typicum: Hauterivian
Translation Gocht, 1957: LPP
Original description: Gocht 1957, p. 172-176: Wetzeliella ?neocomica.
Diagnosis: Shell flattened, extremely variable in shape, generally more or less 4-5 sided, delicate. Closed edge rare; Shell all around mostly developing into bilayered and exteriorly closed projections, which may be located at several levels, but which are essentially limited to the region of the outer margin. Among them, an apical horn, two lateral horns, and an antapical horn smay often be clearly distinguished. Projections and horns often provided with pointed, blunt or trumpet shaped, flat protruberances or processes, which almost exclusively stand along the outline, and rarely on the surface. On the front and back sides projections or processes are sporadic. Along the margins of the apical and antapical horns, the protruberancesare are often arranged alternatively. Lateral horns mostly slightly squat, broad-based, sometimes slightly bent, giving rise to a slightly V-shaped cross-section.
Projections and processes may be considerably reduced or extremely enlarged, as well as the horns, which may also partly be missing or be unrecognizable as such.
Exceptionally, denticulate ridges or idications of a transverse furrow occur on the shell.
Inner body delicate, with a more or less oval outline.
Emended description: Helby, 1987, p. 310-313: Phoberocysta neocomica
Proximochorate cyst, outline rhomboidal with a prominent apical horn, cingular horns, left antapical horn and a periphragm bulge of variable size constituting a right antapical horn. Cingular horns variably developed, usually expressed as stout lateral bosses. Each cingular horn consisting of parts of 2 modified paraplates from each of the precingular and postcingular series and a cingular paraplate (2c) on the left and 2 cingular paraplates (4c and 5c) on the right.
Posterior surface of the lateral tip of the horns, comprising the lateral extension of the postcingular paraplates, often inclined posteriorly. Lateral edges of the cingular horns slope anteriorly towards the cyst, although parasutural ridges give it a distinctive notched appearance, often exaggerated by development of substantial gonal spines. Left antapical horn prominent, usually rounded at the distal end. Cyst 2-layered, cornucavate, but wall layers closely appressed over most of the dorsal and ventral surfaces. Endocyst rhomboidal with small protrusions at horn bases apart from the right antapical horn. Periphragm varying from smooth to finely granulate, scabrate and occasionally perforate. Periphragm bearing a variety of spines and spinules. Large, solid, capitate spines (tapered from a very broad base, and up to 15 Ám long), generally with small spinules.
Spines generally gonal and parasutural and only occasionally intratabular. Spinules (0.5-1Ám high) concentrated at the distal extremities of large spines and horns (particularly the apical and antapical horns) or may occur as scattered intratabular groups, or may be aligned parasuturally. Endophragm usually granulate. Paratabulation indicated by archeopyle, by the location of gonal and intergonal spines and occasionally by less distinct parasutural features such as delicate differentiation of the periphragm (scabration). Paratabulation formula interpreted as 4", 0a, 6"", 6c(?), 6""", 1p, 1"""" (fig.15). Archeopyle apical, type [tA], principle archeopyle suture zigzag with parasulcal notch set off to left side. Paracingulum transverse feature across dorsal surface onto paracingular horns where it is evident as a distinct concavity (exaggerated by gonal spine development) at the lateral edge of the horns. Parasulcus sinous, offset from a midventral position on the hypocyst to a left ventral position on the epicyst. Parasulcal plates not well defined.
Emended diagnosis: Monteil, 1991, p. 477: Muderongia tomaszowensis
Cysts proximate to proximochorate, compressed dorsoventrally, two-layered, cornucavate to delphicavate or circumcavate. Pericyst ceratioid, symmetrical, with 4 prominent horns: 1 apical (axial, type AP I); 2 subequal lateral (axial, type L I), indented; 1 antapical (axial, type ATP I). Left lateral horn may be slightly more reduced than the right one. Horns normal with distal extremities closed and rounded; proximal extremities narrow, except for the antapical horn which may be wider A small rounded bulge can be present in right antapical position (Pl. 3, figs. 1, 2). Endocyst oval to rhombic. Periphragm thin, psilate to scabrate; periphragm may be ornamented by verrucae or processes (stages I to IV). Endophragm thin, psilate to granulate Archeopyle apical, type (4A), with angular margin. Parasulcal notch marked. Operculum free. Paratabulation indicated by archeopyle, by low parasutural ridges or septa, and more or less clearly expressed by distribution and type of processes (stages I to IV), when those are present. Occasionally, periphragm showing penitabular verrucae. Formula:?pr, 4", 0a, 6", 6c, 6""", 1p, 1"""". Pericingulum marked by indentation of lateral horns and by parallel transverse structures. Perisulcus marked by parasulcal notch offset. Parasulcal area not observed.
Dimensions of the holotype (with operculum): 140 Ám x 112 Ám (overall L x I).