Pilina solarium
Encyclopedia
Pilina solarium is an extinct species of a paleozoic Silurian
monoplacophoran. It was first named as Palaeacmaea solarium and described by Gustaf Lindström
from Silurian of Gotland
in Sweden in 1884.
is patelliform and regularly acuminate. The apex
is nearly median or slightly anterior. The outline of the shell is oblongate. The outside of the shell is smooth, only concentrically wrinkled at regular distances by larger elevated ridges, the interstices between them being finely striated by parallel lines. Interiorly there is around the apex a narrow circle of detached muscular scars, visible on the nucleus.
The length of the shell is 6 mm, width 4 mm and the height of the shell is 3 mm.
Silurian
The Silurian is a geologic period and system that extends from the end of the Ordovician Period, about 443.7 ± 1.5 Mya , to the beginning of the Devonian Period, about 416.0 ± 2.8 Mya . As with other geologic periods, the rock beds that define the period's start and end are well identified, but the...
monoplacophoran. It was first named as Palaeacmaea solarium and described by Gustaf Lindström
Gustaf Lindström
Gustaf Lindström was a Swedish paleontologist.He was born in Visby on Gotland. In 1848 he entered Uppsala University, and in 1854 he took his doctor's degree...
from Silurian of Gotland
Gotland
Gotland is a county, province, municipality and diocese of Sweden; it is Sweden's largest island and the largest island in the Baltic Sea. At 3,140 square kilometers in area, the region makes up less than one percent of Sweden's total land area...
in Sweden in 1884.
Shell description
The shellMollusc shell
The mollusc shell is typically a calcareous exoskeleton which encloses, supports and protects the soft parts of an animal in the phylum Mollusca, which includes snails, clams, tusk shells, and several other classes...
is patelliform and regularly acuminate. The apex
Apex (mollusc)
Apex is an anatomical term for the tip of the mollusc shell of a gastropod, scaphopod, or cephalopod mollusc.-Gastropods:The word "apex" is most often used to mean the tip of the spire of the shell of a gastropod...
is nearly median or slightly anterior. The outline of the shell is oblongate. The outside of the shell is smooth, only concentrically wrinkled at regular distances by larger elevated ridges, the interstices between them being finely striated by parallel lines. Interiorly there is around the apex a narrow circle of detached muscular scars, visible on the nucleus.
The length of the shell is 6 mm, width 4 mm and the height of the shell is 3 mm.