Ctenopterus
Encyclopedia
Ctenopterus is a genus of prehistoric eurypterid
of the Family Stylonuridae
. It contains only one species
.
, which lived from the Ordovician
to Lower Permian
periods, were small to very large forms with scales developing into tubercules and knobs. The prosoma (head) exhibited variable shape, with arcuate compound eyes located subcentrally, or anteriorly. Their abdomens were slender. Their walking legs were long and powerful, sometimes characterized by spines. Most genera did not have swimming legs.
Ctenopterus is distinguished by its prosoma (head), which narrows towards the front. All of its legs are walking legs; the second and third pairs are strongly developed, with a double row of numerous flat spines; the last pair is long, without spines. Ctenopterus date from the Silurian to the Devonian periods.
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...
of the Family Stylonuridae
Stylonuridae
Stylonuridae are an extinct family of prehistoric eurypterids within the Superfamily Stylonuroidea.-Description:Stylonuridae, which lived from the Ordovician to Lower Permian periods, were small to very large forms with scales developing into tubercules and knobs. The prosoma exhibited variable...
. It contains only one species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
.
Description
StylonuridsStylonuridae
Stylonuridae are an extinct family of prehistoric eurypterids within the Superfamily Stylonuroidea.-Description:Stylonuridae, which lived from the Ordovician to Lower Permian periods, were small to very large forms with scales developing into tubercules and knobs. The prosoma exhibited variable...
, which lived from the Ordovician
Ordovician
The Ordovician is a geologic period and system, the second of six of the Paleozoic Era, and covers the time between 488.3±1.7 to 443.7±1.5 million years ago . It follows the Cambrian Period and is followed by the Silurian Period...
to Lower Permian
Permian
The PermianThe term "Permian" was introduced into geology in 1841 by Sir Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil; Murchison asserted in 1841 that he named his "Permian...
periods, were small to very large forms with scales developing into tubercules and knobs. The prosoma (head) exhibited variable shape, with arcuate compound eyes located subcentrally, or anteriorly. Their abdomens were slender. Their walking legs were long and powerful, sometimes characterized by spines. Most genera did not have swimming legs.
Ctenopterus is distinguished by its prosoma (head), which narrows towards the front. All of its legs are walking legs; the second and third pairs are strongly developed, with a double row of numerous flat spines; the last pair is long, without spines. Ctenopterus date from the Silurian to the Devonian periods.
Species
- Ctenopterus Clarke & Ruedemann, 1912
- Ctenopterus cestrotus (Clarke, 1907) — Silurian, USA