Slimonia
Encyclopedia
Slimonia is a genus of Silurian
eurypterid
roughly similar to the genus Pterygotus
. Slimonia resembled Pterygotus, save that the former's telson
is larger, and that its body was smaller and more slender than the latter. Unlike Pterygotus, which lived in estuaries, Slimonia species lived exclusively in freshwater environments. Slimonia preyed on smaller fish, such as heterostracans and early osteostracans
by seizing and rending them with its large chelicerae. The largest species of Slimonia was extremely long, around two meters. It carried its body on spindly legs and was likely an ambush predator. The lungs of the species were located on the underside of the body in a series of folds.
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...
eurypterid
Eurypterid
Eurypterids are an extinct group of arthropods related to arachnids which include the largest known arthropods that ever lived. They are members of the extinct order Eurypterida ; which is the most diverse Paleozoic chelicerate order in terms of species...
roughly similar to the genus Pterygotus
Pterygotus
Pterygotus is the second-largest known eurypterid, or sea scorpion and one of the largest arthropods of all time.-Description:...
. Slimonia resembled Pterygotus, save that the former's telson
Telson
The telson is the last division of the body of a crustacean. It is not considered a true segment because it does not arise in the embryo from teloblast areas as do real segments. It never carries any appendages, but a forked "tail" called the caudal furca is often present. Together with the...
is larger, and that its body was smaller and more slender than the latter. Unlike Pterygotus, which lived in estuaries, Slimonia species lived exclusively in freshwater environments. Slimonia preyed on smaller fish, such as heterostracans and early osteostracans
Osteostraci
The class Osteostraci was a group of bony-armored jawless fish, termed "ostracoderms", that lived in what is now North America, Europe and Russia from the Middle Silurian to Late Devonian....
by seizing and rending them with its large chelicerae. The largest species of Slimonia was extremely long, around two meters. It carried its body on spindly legs and was likely an ambush predator. The lungs of the species were located on the underside of the body in a series of folds.
Description
Slimonia is distinguishable by its quadrate (roughly square) prosoma, or head, with small compound eyes on the front corners. They had large cordate bodies, with a narrow postabdomen and a telson with a "strongly expanded anterior half." Their chelicerae (claws) were small; their walking legs had denticles, but no spines. Genital appendages were long and narrow in both males and females.Species
There are three species currently classified under Slimonia:- Slimonia acuminata Salter, 1856 - Silurian, Herefordshire, England
- Slimona boliviana Kjellesvig-Waering, 1973 - Silurian, Cochambamba, Bolivia
- Slimonia dubia Laurie, 1899 - Silurian, Pentland Hills, Scotland