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Hystrichosphaeridium malum
Hystrichosphaeridium malum (Cramer, 1964) Andreeva, 1973
Combination not validly published, since Andreeva, 1973, did not fully reference the basionym.
Now Rhacobrachion. Originally Baltisphaeridium, subsequently Evittia, thirdly Hystrichosphaeridium (combination not validly published), fourthly Multiplicisphaeridium, fifthly (and now) Rhacobrachion.
Andreeva, 1973, implied that the basionym for this species is Hystrichosphaeridium malum.
Holotype: Cramer, 1964, pl.1, fig.8
Age: Silurian (Ludlow)
Original description (Cramer 1964)
Dimensions 0i = about 30 µ; 0t = about 45 µ.
Central body and processes hollow with uniform walls. The central body is roughly spherical, thin walled and transparent. Its wall is irregularly scabrate. The processes are conical, and have the form ofa stout pilar, that ends in a rounded, simple tip. Rarely some reduced secondary appendages near the end of the processes are present. Number of processes rather variable, 10 to 26 (10) in optical section. Frequency and provenance. Rare in the San Pedro Formation. Holotype from 1148, Torrestio, NW-Spain. Known stratigraphical range. San Pedro Formation, Ludlovian, NW-Spain.Similarforms. V. echinodermum St. & \\. has more and shorter appendages and is not scabrate.
Combination not validly published, since Andreeva, 1973, did not fully reference the basionym.
Now Rhacobrachion. Originally Baltisphaeridium, subsequently Evittia, thirdly Hystrichosphaeridium (combination not validly published), fourthly Multiplicisphaeridium, fifthly (and now) Rhacobrachion.
Andreeva, 1973, implied that the basionym for this species is Hystrichosphaeridium malum.
Holotype: Cramer, 1964, pl.1, fig.8
Age: Silurian (Ludlow)
Original description (Cramer 1964)
Dimensions 0i = about 30 µ; 0t = about 45 µ.
Central body and processes hollow with uniform walls. The central body is roughly spherical, thin walled and transparent. Its wall is irregularly scabrate. The processes are conical, and have the form ofa stout pilar, that ends in a rounded, simple tip. Rarely some reduced secondary appendages near the end of the processes are present. Number of processes rather variable, 10 to 26 (10) in optical section. Frequency and provenance. Rare in the San Pedro Formation. Holotype from 1148, Torrestio, NW-Spain. Known stratigraphical range. San Pedro Formation, Ludlovian, NW-Spain.Similarforms. V. echinodermum St. & \\. has more and shorter appendages and is not scabrate.