34
2 Systematic Descriptions
Discussion: Indotriradites (Tiwari 1964) closely resembles Kraeuselisporites
which is treated as its synonym.
Indotriradites is used in the present study to accommodate cavate and zonate
spores with a characteristic-coarse echinate/spinate sculpture on the distal face
which extends to the cingulum and gives it a spinate outline in optical section.
Spines can be very dense giving the spore a thick dark look.
Indotriradites splendens (Balme and Hennelly) (Foster 1979).
Synonymy: Cirratriradites splendens (Balme and Hennelly 1956).
Occurrence: Lower to Upper Permian of Collie–Muja Basin; bore B/973-93
.
Description: Cavate and zonate. Amb triangular. Trilete; scar distinct, laesurae
extending usually onto flange in the form of exinal thickenings. Commissures
usually raised. Structure of ektexine intra-punctate. Sculpture echinate, confined
to distal face, consists of 4–10 µ long spines, with sharp ends, widening towards
their bases to 4–10 µ in diameter. Spines are closely spaced, about 1 spine on a
4 sq. µ area; they extend onto flange, although usually in a reduced size. Flange
uniform in width all around spore equator except for a slight widening around
apices, varying in width from 10 to 20 µ. A dark ring of variable width present at
flange base, representing the distal face infold and the flange base.
Dimensions: 48–60 µ (20 specimens measured).
Remarks and comparison: I. splendens is distinguished by its closely spaced,
wide-based coarse spines confined to its distal face and its intra-punctate structure. Indotriradites korbaensis (Tiwari 1964) has slightly less coarse sculpture,
otherwise closely resembles I. splendens and may well be its synonym. The spores
are distinct from Indotriradites niger by the coarse, densely spaced, wide-based
echinate sculpture that often forms a pseudo-cingulum in I. splendens.
Indotriradites niger (Backhouse 1991).
Diagnosis: Cavate and zonate. Trilete. Amb triangular to rounded-triangular.
Laesurae long. Structure intra-punctate. Sculpture echinate, fading towards the
proximal face and towards flange.
Occurrence/ type locality: Lower to upper Permian of Collie–Muja Basins. More
common in the Lower Permian. Collie Basin site B bore-1980
.
Description: Cavate and zonate. Trilete; laesurae long, extending to equatorial
margin of spore and often onto flange. Amb triangular to rounded-triangular.
Exine cavate and zonate; zona 8–10 µ wide. Structure of ektexine dense, fine intrapunctate. Sculpture echinate. Spines long and often broken at their tips giving the
sculpture a verrucate appearance (Fig. 2.17a).
Dimensions: 45–66 µ (30 specimens measured).
Remarks and comparisons: I. niger is distinguished from most of the other similar
forms of the same genus by its fine, intra-punctate structure, and sparsely distributed echinate sculpture which contrasts with the coarse dense spaced echinate
sculpture of I. splendens.
I. niger was described and designated by Backhouse (1991) from the Collie
Basin. The same author points out the difficulty of assigning the species due
2 Systematic Descriptions
Discussion: Indotriradites (Tiwari 1964) closely resembles Kraeuselisporites
which is treated as its synonym.
Indotriradites is used in the present study to accommodate cavate and zonate
spores with a characteristic-coarse echinate/spinate sculpture on the distal face
which extends to the cingulum and gives it a spinate outline in optical section.
Spines can be very dense giving the spore a thick dark look.
Indotriradites splendens (Balme and Hennelly) (Foster 1979).
Synonymy: Cirratriradites splendens (Balme and Hennelly 1956).
Occurrence: Lower to Upper Permian of Collie–Muja Basin; bore B/973-93
.
Description: Cavate and zonate. Amb triangular. Trilete; scar distinct, laesurae
extending usually onto flange in the form of exinal thickenings. Commissures
usually raised. Structure of ektexine intra-punctate. Sculpture echinate, confined
to distal face, consists of 4–10 µ long spines, with sharp ends, widening towards
their bases to 4–10 µ in diameter. Spines are closely spaced, about 1 spine on a
4 sq. µ area; they extend onto flange, although usually in a reduced size. Flange
uniform in width all around spore equator except for a slight widening around
apices, varying in width from 10 to 20 µ. A dark ring of variable width present at
flange base, representing the distal face infold and the flange base.
Dimensions: 48–60 µ (20 specimens measured).
Remarks and comparison: I. splendens is distinguished by its closely spaced,
wide-based coarse spines confined to its distal face and its intra-punctate structure. Indotriradites korbaensis (Tiwari 1964) has slightly less coarse sculpture,
otherwise closely resembles I. splendens and may well be its synonym. The spores
are distinct from Indotriradites niger by the coarse, densely spaced, wide-based
echinate sculpture that often forms a pseudo-cingulum in I. splendens.
Indotriradites niger (Backhouse 1991).
Diagnosis: Cavate and zonate. Trilete. Amb triangular to rounded-triangular.
Laesurae long. Structure intra-punctate. Sculpture echinate, fading towards the
proximal face and towards flange.
Occurrence/ type locality: Lower to upper Permian of Collie–Muja Basins. More
common in the Lower Permian. Collie Basin site B bore-1980
.
Description: Cavate and zonate. Trilete; laesurae long, extending to equatorial
margin of spore and often onto flange. Amb triangular to rounded-triangular.
Exine cavate and zonate; zona 8–10 µ wide. Structure of ektexine dense, fine intrapunctate. Sculpture echinate. Spines long and often broken at their tips giving the
sculpture a verrucate appearance (Fig. 2.17a).
Dimensions: 45–66 µ (30 specimens measured).
Remarks and comparisons: I. niger is distinguished from most of the other similar
forms of the same genus by its fine, intra-punctate structure, and sparsely distributed echinate sculpture which contrasts with the coarse dense spaced echinate
sculpture of I. splendens.
I. niger was described and designated by Backhouse (1991) from the Collie
Basin. The same author points out the difficulty of assigning the species due