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Hystrichokolpoma denticulatum
Hystrichokolpoma denticulatum Matsuoka, 1974
Holotypus: Matsuoka, 1974, pl.44, fig.3
Locus typicus: Fujiwara-cho, Nara City, Nara Prefecture
Stratum typicum: Early-Middle Miocene
Original diagnosis: Matsuoka, 1974, p. 330
Hemispherical central body with thin wall of granular surface and thin smooth outer wall. Processes formed from outer wall and of two types; large ones with quadrate bases, cylindrical to tubiform with slightly denticulate open end, and small slender processes with slightly bifid distal parts. Tabulation reflected by these processes and shape of archeopyle typical for this genus; 4", 6", 6g, 5""", 1p and 1"""". Each cingular plate indicated by two adjacent slender processes combined at basal parts.
Description: Matsuoka, 1974, p.330
Hystrichokolpoma denticulata is characterized by cylindrical to tubiform large hollow processes with quadrate to trapezoid bases and having a large apical archeopyle. Distal parts of large processes are slightly denticulate. The original apical, precingular, postcingular, posterior intercalary and antapical plates are reflected by these large processes. The first posterior intercalary plate has a small cylindrical to tubiform process, and occupies a position between plates 1""" and 1"""". The original cingular region is indicated by small slender bifid processes. Adjacent two of these slender processes are always connected at the bases. There are about six sulcal processes with distally open or bifid, which occupy a position between plates 1""" and 5""". Its alrge apical archaeopyle has a zig-zag margin and may be formed by the loss of four apical plates.
Dimensions: Diameter of central body 38x42 Ám, length of large processes 14-21 Ám, width of these processes 8-12 Ám, length of small processes 11-17 Ám, diameter of archaeopyle c. 20 Ám. Range diameter of central body 40-50x42-60 Ám, length of large processes 16-22 Ám, width of these processes 8-12 Ám, length of small processes 11-17 Ám, diameter of archaeopyle 20-30 Ám.
Affinities:
Matsuoka, 1974, p.330: The present species is differentiated from Hystrichokolpoma poculum, H. rigaudae, H. unispinum and H. elliptica in having cylindrical to tubiforrm large hollow processes with quadrate to trapezoid bases, slightly denticulate distal margin of them and a two connected slender processes in the cingular region.
Holotypus: Matsuoka, 1974, pl.44, fig.3
Locus typicus: Fujiwara-cho, Nara City, Nara Prefecture
Stratum typicum: Early-Middle Miocene
Original diagnosis: Matsuoka, 1974, p. 330
Hemispherical central body with thin wall of granular surface and thin smooth outer wall. Processes formed from outer wall and of two types; large ones with quadrate bases, cylindrical to tubiform with slightly denticulate open end, and small slender processes with slightly bifid distal parts. Tabulation reflected by these processes and shape of archeopyle typical for this genus; 4", 6", 6g, 5""", 1p and 1"""". Each cingular plate indicated by two adjacent slender processes combined at basal parts.
Description: Matsuoka, 1974, p.330
Hystrichokolpoma denticulata is characterized by cylindrical to tubiform large hollow processes with quadrate to trapezoid bases and having a large apical archeopyle. Distal parts of large processes are slightly denticulate. The original apical, precingular, postcingular, posterior intercalary and antapical plates are reflected by these large processes. The first posterior intercalary plate has a small cylindrical to tubiform process, and occupies a position between plates 1""" and 1"""". The original cingular region is indicated by small slender bifid processes. Adjacent two of these slender processes are always connected at the bases. There are about six sulcal processes with distally open or bifid, which occupy a position between plates 1""" and 5""". Its alrge apical archaeopyle has a zig-zag margin and may be formed by the loss of four apical plates.
Dimensions: Diameter of central body 38x42 Ám, length of large processes 14-21 Ám, width of these processes 8-12 Ám, length of small processes 11-17 Ám, diameter of archaeopyle c. 20 Ám. Range diameter of central body 40-50x42-60 Ám, length of large processes 16-22 Ám, width of these processes 8-12 Ám, length of small processes 11-17 Ám, diameter of archaeopyle 20-30 Ám.
Affinities:
Matsuoka, 1974, p.330: The present species is differentiated from Hystrichokolpoma poculum, H. rigaudae, H. unispinum and H. elliptica in having cylindrical to tubiforrm large hollow processes with quadrate to trapezoid bases, slightly denticulate distal margin of them and a two connected slender processes in the cingular region.