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Hystrichokolpoma fenestreconum
Hystrichokolpoma fenestreconum May, 1980
Now Litosphaeridium. Originally Hystrichokolpoma, subsequently (and now) Litosphaeridium.
HoIotype: May, 1980, pl.3, figs.6-8
Locus typicus: Atlantic Highlands, New Jersey, U.S.A.
Stratum typicum: Maastrichtian
Original description: May, 1980, p.54
Chorate cyst with spherical to ovoidal main body. Bilayered; endophragm smooth; periphragm rugulate between circular and smooth-based processes; formed into processes of two types: larger circular-based, intratabular, conical, hollow, and distally open processes which characterize the pre- and postcingular and antapical plate equivalents; and slender circular-based, slightly tapering, intratabular, hollow, and distally open processes which characterize the apical, cingular, 1p, and often 6"" plate positions. Both types of processes of relatively equal length, differing mainly in diameter and degree of tapering. The 6" is a slender process located immediately below and to the left of the larger 5". The 1p is a slender process nearly contacting the lower, sulcal side of the 1""". Circular process bases encompass smooth areas on the central body, appearing as circular windows. Each plate equivalent is represented by a single plate centered process, and is well-separated from the adjacent processes. The reflected tabulation is ?4, 6", ?c, 5""", 1p, 1"""". Cingulum levorotatory, represented by 3--4 widely spaced, laterally and dorsally positioned, slender processes. Archeopyle apical (Type [A]), corresponding to the position of 3--4 apical plates, represented by only 3 slender processes; the ventral-most appears to be the result of a fusion of the 1" and 4" processes, and may appear single or double-pronged, or ribbon-like.
Discussion: Six specimens were oriented solely for examination of the apical series. The apex is unusual in that it consistently shows only three slender apical processes. One specimen displays suture lines on the apex, which outlined 4 plate equivalents; the ventral-most apical process lies on the suture line between the 1" and 4". This process appears to be the result of a fusion of the processes of both plates (1" and 4"). Frequently this ventral-most process is in some way different from the other two, i.e., being double pronged (sharing one base but bifurcating) or ribbonlike. The 3--4 cingular processes were only observed laterally and dorsally. The antapical process is generally not larger than the other larger-type processes, but may be more parallel sided. No sulcal processes were observed, the position of the sulcus being determined by the apical notch in the archeopyle, which appears to be mid-ventrally aligned, the position of the reduced 6" and 1p, and the larger antapical process. The sulcal area also appears to be broad and open. The ornamentation on the central body between the processes is rugulate; beneath the processes the main body is smooth, forming a smooth circular window on the central body. The processes themself are generally smooth, but may be finely striate.
Now Litosphaeridium. Originally Hystrichokolpoma, subsequently (and now) Litosphaeridium.
HoIotype: May, 1980, pl.3, figs.6-8
Locus typicus: Atlantic Highlands, New Jersey, U.S.A.
Stratum typicum: Maastrichtian
Original description: May, 1980, p.54
Chorate cyst with spherical to ovoidal main body. Bilayered; endophragm smooth; periphragm rugulate between circular and smooth-based processes; formed into processes of two types: larger circular-based, intratabular, conical, hollow, and distally open processes which characterize the pre- and postcingular and antapical plate equivalents; and slender circular-based, slightly tapering, intratabular, hollow, and distally open processes which characterize the apical, cingular, 1p, and often 6"" plate positions. Both types of processes of relatively equal length, differing mainly in diameter and degree of tapering. The 6" is a slender process located immediately below and to the left of the larger 5". The 1p is a slender process nearly contacting the lower, sulcal side of the 1""". Circular process bases encompass smooth areas on the central body, appearing as circular windows. Each plate equivalent is represented by a single plate centered process, and is well-separated from the adjacent processes. The reflected tabulation is ?4, 6", ?c, 5""", 1p, 1"""". Cingulum levorotatory, represented by 3--4 widely spaced, laterally and dorsally positioned, slender processes. Archeopyle apical (Type [A]), corresponding to the position of 3--4 apical plates, represented by only 3 slender processes; the ventral-most appears to be the result of a fusion of the 1" and 4" processes, and may appear single or double-pronged, or ribbon-like.
Discussion: Six specimens were oriented solely for examination of the apical series. The apex is unusual in that it consistently shows only three slender apical processes. One specimen displays suture lines on the apex, which outlined 4 plate equivalents; the ventral-most apical process lies on the suture line between the 1" and 4". This process appears to be the result of a fusion of the processes of both plates (1" and 4"). Frequently this ventral-most process is in some way different from the other two, i.e., being double pronged (sharing one base but bifurcating) or ribbonlike. The 3--4 cingular processes were only observed laterally and dorsally. The antapical process is generally not larger than the other larger-type processes, but may be more parallel sided. No sulcal processes were observed, the position of the sulcus being determined by the apical notch in the archeopyle, which appears to be mid-ventrally aligned, the position of the reduced 6" and 1p, and the larger antapical process. The sulcal area also appears to be broad and open. The ornamentation on the central body between the processes is rugulate; beneath the processes the main body is smooth, forming a smooth circular window on the central body. The processes themself are generally smooth, but may be finely striate.