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Kiokansium hydra
Kiokansium hydra (Duxbury, 1979) Below, 1982; Emendation: Harding, 1986a, p.97-98,100, as Taleisphaera hydra.
Now Taleisphaera. Originally (and now) Taleisphaera, subsequently Kiokansium.
Lentin and Williams, 1985, retained this species in Taleisphaera Duxbury, 1979.
Holotype: Duxbury, 1979, pl.2, figs.1,4
Age: Barremian
Original description (Duxbury, 1979):
Derivation of name: from the Greek Hydra, a fabulous, many-headed water-serpent- referring to the morphology of the individual processes.
Type locality: Division MB, middle Barremian, Speeton Clay, Speeton, Engeland.
Diagnosis: A species having a finely perforate body wall and a subpolygonal, ellipsoidal or ovoidal body shape. The main body length to breadth ratio is always greater than 1. Numerous processes are present and these may be ¼ to 1/3 the body length. Processes are aligned along low, penitabular crests, so that each plate boundary is suggested by a double crest. Gonal processes predominate but crestal ones are not uncommon. Individual processes are proximally flared and distally flared and furcate, sometimes multifurcate, so that numerous hair-like terminal filament may be present running along each process. The archeopyle is formed by detachment of two precingular plates.
Observed dimansions: Holotype 62 x 60 µm. Overall 78(68)60 x 70(58)48 µm. Specimens measured 25.
Remarks: Taleisphaera hydra is a very distinctive species, but nevertheless bears some resemblances to previously describes taxa. The most closely comparable species is Cleistosphaeridium polypes (Cookson and Eisenack, 1962) Davey, 1969, which is similar both in processes type and in body shape and size. Cleistosphaeridium polypes is, however, considered to possess an apical archeopyle, and it also lacks the penitabular crests so characteristic of T. hydra.
In their subpolygnal shape, some specimens of T. hydra superficially resemble species of Spiniferites Mantell, 1850, emend. Sarjeant 1970. However, the two-plate precingular archeopyle and “double crests” of T. hydra contracts strongly with the single plate precingular archeopyle and single sutural crests of Spiniferites. Also, the distal process furcation in T. hydra tends to produce numerous hair-like, terminal spines; this feature is not observed in Spiniferites.
Now Taleisphaera. Originally (and now) Taleisphaera, subsequently Kiokansium.
Lentin and Williams, 1985, retained this species in Taleisphaera Duxbury, 1979.
Holotype: Duxbury, 1979, pl.2, figs.1,4
Age: Barremian
Original description (Duxbury, 1979):
Derivation of name: from the Greek Hydra, a fabulous, many-headed water-serpent- referring to the morphology of the individual processes.
Type locality: Division MB, middle Barremian, Speeton Clay, Speeton, Engeland.
Diagnosis: A species having a finely perforate body wall and a subpolygonal, ellipsoidal or ovoidal body shape. The main body length to breadth ratio is always greater than 1. Numerous processes are present and these may be ¼ to 1/3 the body length. Processes are aligned along low, penitabular crests, so that each plate boundary is suggested by a double crest. Gonal processes predominate but crestal ones are not uncommon. Individual processes are proximally flared and distally flared and furcate, sometimes multifurcate, so that numerous hair-like terminal filament may be present running along each process. The archeopyle is formed by detachment of two precingular plates.
Observed dimansions: Holotype 62 x 60 µm. Overall 78(68)60 x 70(58)48 µm. Specimens measured 25.
Remarks: Taleisphaera hydra is a very distinctive species, but nevertheless bears some resemblances to previously describes taxa. The most closely comparable species is Cleistosphaeridium polypes (Cookson and Eisenack, 1962) Davey, 1969, which is similar both in processes type and in body shape and size. Cleistosphaeridium polypes is, however, considered to possess an apical archeopyle, and it also lacks the penitabular crests so characteristic of T. hydra.
In their subpolygnal shape, some specimens of T. hydra superficially resemble species of Spiniferites Mantell, 1850, emend. Sarjeant 1970. However, the two-plate precingular archeopyle and “double crests” of T. hydra contracts strongly with the single plate precingular archeopyle and single sutural crests of Spiniferites. Also, the distal process furcation in T. hydra tends to produce numerous hair-like, terminal spines; this feature is not observed in Spiniferites.