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Adnatosphaeridium williamsii
Adnatosphaeridium williamsii, Islam, 1983
Holotype: Islam, 1983, pl.4, fig.9
Paratype; Islam, 1983
Locus typicus: Isle of Sheppey, England
Stratum typicum: Eocene, Tertiary
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Original description: [Islam, 1983, p. 81-82]:
Diagnosis:
Cyst subspherical, broader than long, skolochorate and biphragmal; endophragm chagrinate; periphragm psilate; possesses thin solid processes with little variation in width of stem, proximally little wide, distally widen to filiform extremities where from solid trabeculae branch out to interconnect neighboring processes; trabeculae sometimes themselves partly filiform and bear a few free spines; paracingulum not recognizable; paratabulation indeterminable; archeopyle apical type tA.
Dimensions:
Holotype: overall dimensions 78 x 88 µm, endocyst 44 x 47 µm.
Range: overall length 83(86)99 µm, breadth 83(93)104 µm, endocyst length 43(49)57 µm, breadth 39(52)62 µm.
Affinities:
This species resembles A. filiferum (Cookson & Eisenack 1958) Williams & Downie 1969 but can be readily distinguished by the lack of tertiary
branchlets which was also noted by Williams (1963) who recorded this species as A. filiferum from the London Clay. It differs from A. multispinosum in possessing filiform distal extremities of processes and generally lacking free spines.
Holotype: Islam, 1983, pl.4, fig.9
Paratype; Islam, 1983
Locus typicus: Isle of Sheppey, England
Stratum typicum: Eocene, Tertiary
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Islam, 1983, p. 81-82]:
Diagnosis:
Cyst subspherical, broader than long, skolochorate and biphragmal; endophragm chagrinate; periphragm psilate; possesses thin solid processes with little variation in width of stem, proximally little wide, distally widen to filiform extremities where from solid trabeculae branch out to interconnect neighboring processes; trabeculae sometimes themselves partly filiform and bear a few free spines; paracingulum not recognizable; paratabulation indeterminable; archeopyle apical type tA.
Dimensions:
Holotype: overall dimensions 78 x 88 µm, endocyst 44 x 47 µm.
Range: overall length 83(86)99 µm, breadth 83(93)104 µm, endocyst length 43(49)57 µm, breadth 39(52)62 µm.
Affinities:
This species resembles A. filiferum (Cookson & Eisenack 1958) Williams & Downie 1969 but can be readily distinguished by the lack of tertiary
branchlets which was also noted by Williams (1963) who recorded this species as A. filiferum from the London Clay. It differs from A. multispinosum in possessing filiform distal extremities of processes and generally lacking free spines.