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Kaiwaradinium scrutillinum
Kaiwaradinium scrutillinum Backhouse, 1987
Holotype: Backhouse, 1987, figs.6A-B,11G-H; Fensome et al., 1996, figs.4-5,7-8 - p.2341; Fauconnier and Masure, 2004, pl.51, figs.1-3.
Locus typicus: Perth Basin, Australia
Stratum typicum: Valanginian
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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.
Kaiwaradinium scrutillinum Backhouse, 1987, has the process formula: 4', 5-6", 0c, 5"’, 0-1p, 1"”. The archeopyle is apical with short accessory archeopyle sutures developed in the precingulars. Trumpet shaped processes are open distally. The cyst wall is granulate. Paracingulum on some specimens denoted by a narrow, shallow groove bounded by low ridges and offset at the parasulcus. K.scrutillinum is considerably smaller and has a less coarsely scuptured body than K.buccinatum. Size: length of central body (without operculum) 47-68 µm, width 32-51 µm, process length 10-36 µm.
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Original description: Backhouse, 1987, p. 217
Medium-sized skolochorate cyst, body tubular to ovoidal, apex and antapex rounded. Endophragm and periphragm appressed except where the periphragm forms intratabular processes. Cyst body 1-2.5 Ám thick, thickest in the cingular area. Surface sculpture of low interconnected grana grading to fine punctation apically and antapically. Paracingulum expressed on some specimens by a narrow, shallow groove bounded by low ridges and offset at the parasulcus. Trumpet-shaped processes open distally and closed proximally by the endophragm. Process walls unperforated and distal margins ragged with occasional U-shaped invaginations.
Processes sometimes removed by breakage leaving small circular stumps. Most specimens bearing 15, 16, or 17 processes depending on the presence or absence of the 6" and 1p processes. A majority of specimens with a Ip process, but occasionally absent, as in the holotype. 6 " process more frequently absent, as on the holotype and one paratype (Figs IIG, 14A). Apical and antapical processes often shorter than the precingular and postcingular processes. Process formula: 4', 5-6'', 0c, 5''', 0-1p, 1''''. Archeopyle apical, type [tA], operculum missing from most specimens. Principal archeopyle suture exhibiting a moderately deep sulcal notch and short but distinct accessory sutures indicating 6 precingular paraplates.
Dimensions. Length of holotype cyst body including operculum 69 Ám, width 43 Ám. Range of cyst body length with operculum missing 47(59)68 Ám, width 32(43)51 Ám, length of proceses 10-36 Ám.
Affinities:
Backhouse, 1987, p. 219: The paratabulation formed by low ridges at the paracingulum extends over much of the cyst body in some specimens from northern Australia (pers. comm. Helby). Kaiwaradinium scrutillinum is considerably smaller and has a less coarsly scuptured body surface than K. buccinatum. Wilson described 17-18 processes for K. buccinatum whereas K. scrutillinum displays 15, 16 or 17 proceses, K. ramosum Wilson 1984 possess 17 processes, which display strongly branched tips (Wilson, 1984). K. ramosum is also considerably larger than K. scrutillinum.
Holotype: Backhouse, 1987, figs.6A-B,11G-H; Fensome et al., 1996, figs.4-5,7-8 - p.2341; Fauconnier and Masure, 2004, pl.51, figs.1-3.
Locus typicus: Perth Basin, Australia
Stratum typicum: Valanginian
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Kaiwaradinium scrutillinum Backhouse, 1987, has the process formula: 4', 5-6", 0c, 5"’, 0-1p, 1"”. The archeopyle is apical with short accessory archeopyle sutures developed in the precingulars. Trumpet shaped processes are open distally. The cyst wall is granulate. Paracingulum on some specimens denoted by a narrow, shallow groove bounded by low ridges and offset at the parasulcus. K.scrutillinum is considerably smaller and has a less coarsely scuptured body than K.buccinatum. Size: length of central body (without operculum) 47-68 µm, width 32-51 µm, process length 10-36 µm.
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Original description: Backhouse, 1987, p. 217
Medium-sized skolochorate cyst, body tubular to ovoidal, apex and antapex rounded. Endophragm and periphragm appressed except where the periphragm forms intratabular processes. Cyst body 1-2.5 Ám thick, thickest in the cingular area. Surface sculpture of low interconnected grana grading to fine punctation apically and antapically. Paracingulum expressed on some specimens by a narrow, shallow groove bounded by low ridges and offset at the parasulcus. Trumpet-shaped processes open distally and closed proximally by the endophragm. Process walls unperforated and distal margins ragged with occasional U-shaped invaginations.
Processes sometimes removed by breakage leaving small circular stumps. Most specimens bearing 15, 16, or 17 processes depending on the presence or absence of the 6" and 1p processes. A majority of specimens with a Ip process, but occasionally absent, as in the holotype. 6 " process more frequently absent, as on the holotype and one paratype (Figs IIG, 14A). Apical and antapical processes often shorter than the precingular and postcingular processes. Process formula: 4', 5-6'', 0c, 5''', 0-1p, 1''''. Archeopyle apical, type [tA], operculum missing from most specimens. Principal archeopyle suture exhibiting a moderately deep sulcal notch and short but distinct accessory sutures indicating 6 precingular paraplates.
Dimensions. Length of holotype cyst body including operculum 69 Ám, width 43 Ám. Range of cyst body length with operculum missing 47(59)68 Ám, width 32(43)51 Ám, length of proceses 10-36 Ám.
Affinities:
Backhouse, 1987, p. 219: The paratabulation formed by low ridges at the paracingulum extends over much of the cyst body in some specimens from northern Australia (pers. comm. Helby). Kaiwaradinium scrutillinum is considerably smaller and has a less coarsly scuptured body surface than K. buccinatum. Wilson described 17-18 processes for K. buccinatum whereas K. scrutillinum displays 15, 16 or 17 proceses, K. ramosum Wilson 1984 possess 17 processes, which display strongly branched tips (Wilson, 1984). K. ramosum is also considerably larger than K. scrutillinum.