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Dapcodinium semitabulatum
Dapcodinium semitabulatum (Morgenroth, 1970) D÷rh÷fer and Davies, 1980
Now Mancodinium. Originally (and now) Mancodinium, subsequently Dapcodinium.
Tax. sr. synonym of Parvulodinium penitabulatum Davies, 1983, according to Prauss, 1989.
Lentin and Williams, 1985, retained this species in Mancodinium Morgenroth, 1970.
Holotype: Morgenroth, 1970, pl. 12, fig. 3
Locus typicus: "Amaltheen" beds, Canal Hildesheim, east of Luehnde, Germany
Stratum typicum: Late Pliensbachian
Original description: Morgenroth, 1970, p. 352-353: Mancodinium semitabulatum
Diagnosis: Test ovoidal; epitract slightly shorter than hypotract. Wall thin; surface of test granular, rarely areolated. Test irregularly covered with very short massive spines, which are commonly capitate distally. Reflected tabulation: 4", 4a, 7"", 0c, 0""", 0p, 0"""". Sutures between plate equivalents on epitract marked by absence of granulation. A laevo-rotatory cingulum and a sulcus are sometimes indicated by slight intrusions into the wall. Apical horn short, distally expanded.
Dimensions: Holotype: breadth of test 39 Ám. Cotype: length 43 Ám, breadth 35 Ám. Range: length 39(43)46 Ám, breadth 30(38)44 Ám. Length of apical horn: 3-5 Ám. 35 specimens measured.
Description: The wall of the ovoidal test is about 1 Á thick. Its surface is normally clearly granular, but on two specimens it is areolated. The test of most of the specimens is more or less densely covered with 1-2 Á high massive spines which are commonly flattened distally. These spines sometimes give the impression of being arranged in loose "groups". However, the position of these "groups" on the hypotract shows no pattern which could indicate a reflected tabulation. The thin sutures between the plates of the epitract are free of granulation and spines. Four apical plates are reflected (pl. 12, fig. 3, 4). Plate 1" is elongate and occupies the anterior prolongation of the sulcus. Plates 2" and 4" seem to be pentagonal, while plate 3" seems to be septagonal in shape. Plate 3" carries a small apical horn, which is expanded distally. Between the seven pentagonal precingular plates and the apical plates, four pentagonal anterior intercalary plates are reflected (pl. 12, fig. 3, 4). On some of specimens a slight intrusion into the wall below the precingular plates indicates an undivided laevo-rotatory cingulum. A sulcus is commonly indicated by a ventral intrusion which is more strongly developed on the hypotract (pl. 12, fig. 3, pl. 13, fig. 4). None of the specimens available shows traces of a reflected tabulation on the hypotract. The archeopyle is formed by the loss of a free operculum composed of all plates reflected on the epitract. The operculum is divided into eight pieces. A rupture directly above the precingular plates separates one opercular piece consisting of the four apical and four anteriorly intercalary plates (pl. 12, fig. 3-6; pl. 13, fig. 1). After this rupture has taken place the seven precingular plates are discarded separately (pl. 12, fig. 3, 6). From most of the specimens, only isolated hypotracts have been found. Only exceptionally some precingular plates, still loosely connected with the hypotract, have been observed (pl. 13, fig. 2, 4).
Now Mancodinium. Originally (and now) Mancodinium, subsequently Dapcodinium.
Tax. sr. synonym of Parvulodinium penitabulatum Davies, 1983, according to Prauss, 1989.
Lentin and Williams, 1985, retained this species in Mancodinium Morgenroth, 1970.
Holotype: Morgenroth, 1970, pl. 12, fig. 3
Locus typicus: "Amaltheen" beds, Canal Hildesheim, east of Luehnde, Germany
Stratum typicum: Late Pliensbachian
Original description: Morgenroth, 1970, p. 352-353: Mancodinium semitabulatum
Diagnosis: Test ovoidal; epitract slightly shorter than hypotract. Wall thin; surface of test granular, rarely areolated. Test irregularly covered with very short massive spines, which are commonly capitate distally. Reflected tabulation: 4", 4a, 7"", 0c, 0""", 0p, 0"""". Sutures between plate equivalents on epitract marked by absence of granulation. A laevo-rotatory cingulum and a sulcus are sometimes indicated by slight intrusions into the wall. Apical horn short, distally expanded.
Dimensions: Holotype: breadth of test 39 Ám. Cotype: length 43 Ám, breadth 35 Ám. Range: length 39(43)46 Ám, breadth 30(38)44 Ám. Length of apical horn: 3-5 Ám. 35 specimens measured.
Description: The wall of the ovoidal test is about 1 Á thick. Its surface is normally clearly granular, but on two specimens it is areolated. The test of most of the specimens is more or less densely covered with 1-2 Á high massive spines which are commonly flattened distally. These spines sometimes give the impression of being arranged in loose "groups". However, the position of these "groups" on the hypotract shows no pattern which could indicate a reflected tabulation. The thin sutures between the plates of the epitract are free of granulation and spines. Four apical plates are reflected (pl. 12, fig. 3, 4). Plate 1" is elongate and occupies the anterior prolongation of the sulcus. Plates 2" and 4" seem to be pentagonal, while plate 3" seems to be septagonal in shape. Plate 3" carries a small apical horn, which is expanded distally. Between the seven pentagonal precingular plates and the apical plates, four pentagonal anterior intercalary plates are reflected (pl. 12, fig. 3, 4). On some of specimens a slight intrusion into the wall below the precingular plates indicates an undivided laevo-rotatory cingulum. A sulcus is commonly indicated by a ventral intrusion which is more strongly developed on the hypotract (pl. 12, fig. 3, pl. 13, fig. 4). None of the specimens available shows traces of a reflected tabulation on the hypotract. The archeopyle is formed by the loss of a free operculum composed of all plates reflected on the epitract. The operculum is divided into eight pieces. A rupture directly above the precingular plates separates one opercular piece consisting of the four apical and four anteriorly intercalary plates (pl. 12, fig. 3-6; pl. 13, fig. 1). After this rupture has taken place the seven precingular plates are discarded separately (pl. 12, fig. 3, 6). From most of the specimens, only isolated hypotracts have been found. Only exceptionally some precingular plates, still loosely connected with the hypotract, have been observed (pl. 13, fig. 2, 4).