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Woodinia pedis
Woodinia *pedis Riding and Helby, 2001d, p.99, figs.19A–T. Holotype: Riding and Helby, 2001d, figs.19K–M. N.I.A. Age: late Callovian.
Original description (Riding and Helby, 2001d)
A subrectangular to rounded subtriangular species of Woodinia. Two small lateral antapical protuberances are normally developed, imparting a slight antapical concavity. Rounded subquadrate or subrectangular , intratabular pad-like areas of differentiated autophragm in which short, slender, solid dense, trabeculate processes are developed. These processes may be coalesce to form anastomosing crests. The antapical processes/crests are the longest and extend laterally to form pedestal-like features. The ornamentation on the apical paraplate series may appear to be merged. The 'pads' on the elongate postcingular paraplate series are inserted close to the prominent, indeted, paracingulum, which is close to the apex. 'Pads' occupy the majority of the small precingular paraplates series. The paracingulum and parasulcus are emphasised by the adjacent precingular and postcingular 'pads'. The very small parasulcal notch is close to mid ventral in position. Autophagm is microgranulate to occasionally microreticulate. The apical paraplate series (the operculum) is flat and very small.
Dimensions (µm; n=32) Min. (Mean) Max.
Length of cyst body (excl. operculum): 30 (34) 40
Width of cyst body at anatpex: 16 (22) 27
Width of cyst body at equator (postcingulars): 12 (19) 26
Width of cyst body at apex (archaeopyle suture): 11 (15) 20
Length of processes/crests: 1 (2) 4
The measured specimens are all from a sidewall core sample in Challis-11 ST1 well at 1552.50m.
Comments. This species is a distinctly subrectangular/subtriangular form of Woodinia. The distribution of the ornamentation gives a characteristic profile in lateral or dorsoventral view. The cyst has a banded appearance, reflecting the development of differentiated autophragmal 'pads' on the precingular, postcingular and antapical paraplate series.
Comparison. Woodinia pedis is similar in overall morphology to the Oxfordian species W. bensonii Riding and Helby 2001e. Woodinia bensonii, however, is rounded subtriangular in dorsoventral outline, having proment lateral antapical protuberances which frequently impart a significant antapical concavity. The latter species also only has regular intratabular 'pads' of differentiated autophragm on the precingular paraplate series. This contrasts markedly with the thicker, more regular intratabular ornamentation, particularly in the postcingular paraplate series, of W. pedis. Woodinia bensonii also lacks the skirt-like flange to the antapex, formed by the relatively prominent antapical ornamentation characteristic of W. pedis .
Derivation of name. From the Latin pedis meaning foot and referring to the prominent, foot-like or pedestal-like antapical differentiated autophragmal protuberanes.
Holotype and type locality. Figures 19K-M, CPC 35490, Challis-11 ST2, sidewall core sample at 1842.00m.
Stratigraphical distribution. Woodinia pedis has been recorded from the late Callovian strata of the Timor Sea region and is confined to the lower Rigaudella aemula Zone (subzones 7aiib to 7aiia). It is most prominent and characteristic of subzones 7aiibia-7aiiaii.
Original description (Riding and Helby, 2001d)
A subrectangular to rounded subtriangular species of Woodinia. Two small lateral antapical protuberances are normally developed, imparting a slight antapical concavity. Rounded subquadrate or subrectangular , intratabular pad-like areas of differentiated autophragm in which short, slender, solid dense, trabeculate processes are developed. These processes may be coalesce to form anastomosing crests. The antapical processes/crests are the longest and extend laterally to form pedestal-like features. The ornamentation on the apical paraplate series may appear to be merged. The 'pads' on the elongate postcingular paraplate series are inserted close to the prominent, indeted, paracingulum, which is close to the apex. 'Pads' occupy the majority of the small precingular paraplates series. The paracingulum and parasulcus are emphasised by the adjacent precingular and postcingular 'pads'. The very small parasulcal notch is close to mid ventral in position. Autophagm is microgranulate to occasionally microreticulate. The apical paraplate series (the operculum) is flat and very small.
Dimensions (µm; n=32) Min. (Mean) Max.
Length of cyst body (excl. operculum): 30 (34) 40
Width of cyst body at anatpex: 16 (22) 27
Width of cyst body at equator (postcingulars): 12 (19) 26
Width of cyst body at apex (archaeopyle suture): 11 (15) 20
Length of processes/crests: 1 (2) 4
The measured specimens are all from a sidewall core sample in Challis-11 ST1 well at 1552.50m.
Comments. This species is a distinctly subrectangular/subtriangular form of Woodinia. The distribution of the ornamentation gives a characteristic profile in lateral or dorsoventral view. The cyst has a banded appearance, reflecting the development of differentiated autophragmal 'pads' on the precingular, postcingular and antapical paraplate series.
Comparison. Woodinia pedis is similar in overall morphology to the Oxfordian species W. bensonii Riding and Helby 2001e. Woodinia bensonii, however, is rounded subtriangular in dorsoventral outline, having proment lateral antapical protuberances which frequently impart a significant antapical concavity. The latter species also only has regular intratabular 'pads' of differentiated autophragm on the precingular paraplate series. This contrasts markedly with the thicker, more regular intratabular ornamentation, particularly in the postcingular paraplate series, of W. pedis. Woodinia bensonii also lacks the skirt-like flange to the antapex, formed by the relatively prominent antapical ornamentation characteristic of W. pedis .
Derivation of name. From the Latin pedis meaning foot and referring to the prominent, foot-like or pedestal-like antapical differentiated autophragmal protuberanes.
Holotype and type locality. Figures 19K-M, CPC 35490, Challis-11 ST2, sidewall core sample at 1842.00m.
Stratigraphical distribution. Woodinia pedis has been recorded from the late Callovian strata of the Timor Sea region and is confined to the lower Rigaudella aemula Zone (subzones 7aiib to 7aiia). It is most prominent and characteristic of subzones 7aiibia-7aiiaii.