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Nannoceratopsis gracilis var. gracilis
Nannoceratopsis gracilis var. gracilis; Emendations: Evitt, 1962, p.1129–1130; van Helden, 1977, p.165.
Name illegitimate. Jr. homonym of Nannoceratopsis gracilis Alberti, 1961 and name not validly published since Prauss, 1989, did not designate a holotype.
By providing an emended diagnosis for Nannoceratopsis gracilis var. gracilis and excluding the original type of the species Nannoceratopsis gracilis, Prauss, 1989, in effect created a jr. homonym of Nannoceratopsis gracilis.
Holotype: not designated
Stratum typicum: Late Toarcian-Middle Callovian
Translation Prauss, 1989: LPP
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Nannoceratopsis gracilis Alberti, 1961, emend. Evitt, 1962, emend. van Helden, 1977 according to van Helden (1977, p.165) has a variable lateral outline. It is subtriangular, with two antapical horns ( ventral horn always much shorter and less well developed than the dorsal horn), to nearly ovoid with a poorly developed ventral horn and a pronounced dorsal horn. Postcingular ventral area above ventral horn and below parasulcal area more or less straight and parallel to apical-antapical axis, sometimes pronounced bulging. Periphragm sculpture reticulate. This emendation restricts the morphology to forms having a distinctly reticulate ornamentation, one dorsal antapical horn and one short ventral antapical horn, which may be poorly developed. It excludes forms having a microreticulate to scabrate or nearly smooth ornamentation and a distinctly ovoid, rounded outline with only the dorsal antapical horn developed. Size: length 72-77 µm, width 47-51 µm..
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Original description: Alberti 196, p. 30: Nannoceratopsis? gracilis
Diagnosis: Shell flattened, outline rounded pentagonal. Lateral sides often convex. Apical horn small, mostly offset. Strong antapical horns not equal in length, diverging and distally narrowing quickly, the tips slightly blunt. Without cingulum. Surface of the shell bearing a net-like sculpture.
Additions: the antapical horns are often shaped like a gothic arch, and mostly one horn is reduced. The short apical horn is distally blunt.
Dimensions: Holotype: length 78 Ám, width 52 Ám. Other specimens: length 72-77 Ám, width 47-51 Ám (11 specimens).
Emended description: Prauss, 1989, p. 13
A varietas of the species N. gracilis with subtrapezoidal outline in lateral view, a short ventral and a longer dorsal antapical horn. The pedium is solid, the luxuria is microreticulate. The sagittal band is delimited by low seams, which, ventrally and at the distal parts of the horns, are often raised like a ledge and perforate.
Dimensions: l: 86,5(89,4)96,1 Ám, w: 50,0(55,5)59,6 ÁÁ; l:w (average) 1,6.
Affinities: Prauss, 1989, p.13
This form differs from N. gracilis var. obsoletus in the larger l:w ratio, a more pronounced dorsal antapical horn and the microreticulate surface structure. The ledges delimiting the sagittal band are mostly clearly expressed in N. gracilis var. gracilis.
Name illegitimate. Jr. homonym of Nannoceratopsis gracilis Alberti, 1961 and name not validly published since Prauss, 1989, did not designate a holotype.
By providing an emended diagnosis for Nannoceratopsis gracilis var. gracilis and excluding the original type of the species Nannoceratopsis gracilis, Prauss, 1989, in effect created a jr. homonym of Nannoceratopsis gracilis.
Holotype: not designated
Stratum typicum: Late Toarcian-Middle Callovian
Translation Prauss, 1989: LPP
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Nannoceratopsis gracilis Alberti, 1961, emend. Evitt, 1962, emend. van Helden, 1977 according to van Helden (1977, p.165) has a variable lateral outline. It is subtriangular, with two antapical horns ( ventral horn always much shorter and less well developed than the dorsal horn), to nearly ovoid with a poorly developed ventral horn and a pronounced dorsal horn. Postcingular ventral area above ventral horn and below parasulcal area more or less straight and parallel to apical-antapical axis, sometimes pronounced bulging. Periphragm sculpture reticulate. This emendation restricts the morphology to forms having a distinctly reticulate ornamentation, one dorsal antapical horn and one short ventral antapical horn, which may be poorly developed. It excludes forms having a microreticulate to scabrate or nearly smooth ornamentation and a distinctly ovoid, rounded outline with only the dorsal antapical horn developed. Size: length 72-77 µm, width 47-51 µm..
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Original description: Alberti 196, p. 30: Nannoceratopsis? gracilis
Diagnosis: Shell flattened, outline rounded pentagonal. Lateral sides often convex. Apical horn small, mostly offset. Strong antapical horns not equal in length, diverging and distally narrowing quickly, the tips slightly blunt. Without cingulum. Surface of the shell bearing a net-like sculpture.
Additions: the antapical horns are often shaped like a gothic arch, and mostly one horn is reduced. The short apical horn is distally blunt.
Dimensions: Holotype: length 78 Ám, width 52 Ám. Other specimens: length 72-77 Ám, width 47-51 Ám (11 specimens).
Emended description: Prauss, 1989, p. 13
A varietas of the species N. gracilis with subtrapezoidal outline in lateral view, a short ventral and a longer dorsal antapical horn. The pedium is solid, the luxuria is microreticulate. The sagittal band is delimited by low seams, which, ventrally and at the distal parts of the horns, are often raised like a ledge and perforate.
Dimensions: l: 86,5(89,4)96,1 Ám, w: 50,0(55,5)59,6 ÁÁ; l:w (average) 1,6.
Affinities: Prauss, 1989, p.13
This form differs from N. gracilis var. obsoletus in the larger l:w ratio, a more pronounced dorsal antapical horn and the microreticulate surface structure. The ledges delimiting the sagittal band are mostly clearly expressed in N. gracilis var. gracilis.