| Eldredgeops Temporal range: | |
|---|---|
 | |
| Eldredgeops milleri | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | † Trilobita |
| Order: | † Phacopida |
| Family: | † Phacopidae |
| Genus: | † Eldredgeops Struve, 1990 |
| Species | |
 | Wikimedia Commons has media related to Eldredgeops . |
Eldredgeops is a genus of trilobites in the order Phacopida, family Phacopidae, known from the late Middle and earliest Upper Devonian of Morocco and the USA.
Like in all sighted Phacopina, the eyes of Eldredgeops are composed of very large (0.5mm in Eldredgeops rana ), separately set lenses without a common cornea (so called schizochroal eyes), and like almost all other Phacopina, the articulate mid-length part of the body (or thorax) in Eldredgeops has 11 segments.
In contrast to the related Phacops , Eldredgeops generally has a raised ridge along the ventral margin of the cephalon, the glabella is more inflated, the lateral parts of the preoccipital ring are rectangular (and not round), the palpebral area and palpebral lobe are larger than in P. latifrons (the type species of Phacops), and there is no fold right behind the posterior vertical row of lenses nor an isolated raised area just below the lenses. [1]
All phacopids died out in North America during the Kačák Event at the end of the Eifelian. The phacopids returned to North America during the early Givetian with the emigration of Eldredgeops species from Morocco. [1]
The species included in Eldredgeops were previously regarded as belonging to Phacops. It was considered however that the post-Eifelian North-American relatives of P. rana differ sufficiently from those found in Africa and Europe to be assigned to a separate genus. The new name is used for the North American species as the type species Phacops latifrons is European. However, old combinations like Phacops rana are widely used among fossil collectors. [1] Pre-Givetian North-American species previously included in Phacops have also been reassigned, such as P. cristatus (now referred to Viaphacops), P. microps and P. raymondi (now Kainops ), P. cambelli, P. birdsongensis, P. claviger and P. logani (now Paciphacops ). [2]
Trilobites are extinct marine arthropods that form the class Trilobita. Trilobites form one of the earliest-known groups of arthropods. The first appearance of trilobites in the fossil record defines the base of the Atdabanian stage of the Early Cambrian period and they flourished throughout the lower Paleozoic before slipping into a long decline, when, during the Devonian, all trilobite orders except the Proetida died out. The last extant trilobites finally disappeared in the mass extinction at the end of the Permian about 252 million years ago. Trilobites were among the most successful of all early animals, existing in oceans for almost 270 million years, with over 20,000 species having been described.
Eldredgeops rana is a species of trilobite from the middle Devonian period. Their fossils are found chiefly in the northeastern United States, and southwestern Ontario.
Phacopida ("lens-face") is an order of trilobite that lived from the Late Cambrian to the Late Devonian. It is made up of a morphologically diverse group of related suborders.
The Phacopina comprise a suborder of the trilobite order Phacopida. Species belonging to the Phacopina lived from the Lower Ordovician (Tremadocian) through the end of the Upper Devonian (Famennian). The one unique feature that distinguishes Phacopina from all other trilobites are the very large, separately set lenses without a common cornea of the compound eye.
Phacopidae is a family of phacopid trilobites that ranges from the Lower Ordovician to the Upper Devonian, with representatives in all paleocontinents.
Phacops is a genus of trilobites in the order Phacopida, family Phacopidae, that lived in Europe, northwestern Africa, North and South America and China from the Late Ordovician until the very end of the Devonian, with a broader time range described from the Late Ordovician. It was a rounded animal, with a globose head and large eyes, and probably fed on detritus. Phacops is often found rolled up ("volvation"), a biological defense mechanism that is widespread among smaller trilobites but further perfected in this genus.
Ductina is a genus of extinct, small to average sized, eyeless phacopid trilobite, that lived during the Devonian.
Chotecops is a genus of trilobites from the order Phacopida, suborder Phacopina, family Phacopidae. It was initially erected as a subgenus of Phacops but some later authors thought it distinctive enough to raise its status. Species assigned to this genus occur between the Emsian and the Famennian. Chotecops is the most abundant trilobite in the Hunsrück Slate and due to the excellent preservation, often soft tissue such as antennae and legs have been preserved as a thin sheet of pyrite.
Drotops is a genus of trilobites from the order Phacopida, family Phacopidae that lived during the Eifelian of the Middle Devonian. It was described by Struve in 1990 under type species Drotops megalomanicus. Their fossils are found in present-day Morocco, specifically the Maïder Region located South West of Erfoud.
Trimerocephalus is a genus of eyeless trilobites from the order Phacopida, family Phacopidae. It lived during the final stage of the Devonian, the Famennian, and became extinct at the end of this stage, together with all other trilobites with the exception of some Proetida. It can be found in Australia, the Czech Republic, France, Germany, Iran, Kazakhstan, Morocco, Poland, the Russian Federation (Urals), Spain, and the United Kingdom (England).
Homosteus is a genus of flattened arthrodire placoderm from the Middle Devonian. Fossils are found primarily in Eifelian-epoch aged strata of Europe, Canada, Greenland, and Estonia. All of the species had comparatively large, flattened heads with, as suggested by the upward opening orbits, upward-pointing eyes. These adaptations suggest that the various species were benthic predators. A study on Titanichthys, in contrast, suggests that species of Homosteus may have been filter-feeders instead.
Erbenochile is a genus of spinose phacopid trilobite, of the family Acastidae, found in Lower to Middle Devonian age rocks from Algeria and Morocco. Originally described from an isolated pygidium, the first complete articulated specimen of E. erbeni revealed the presence of extraordinarily tall eyes:
"Straight-sided towers of lenses... with [up to] 18 lenses in a vertical file"
Boeckops is a genus of trilobites in the order Phacopida, which existed in what is now the Czech Republic. It was described by Chlupac in 1972, and the type species is Boeckops boecki, which was originally described as Phacops boecki by Hawle and Corda in 1847. Boeckops is also been discriped from the lower Devonian of Morocco and Algeria. The Genus Boeckops is interpreted as intermediate from between the traditional genus concept of Phacops and Reedops. The Genus Boeckops is regarded as problematic or difficult by McKellar et Chatterton 2009.
Morocconites malladoides is an average size trilobite, which lived during the Devonian period, in what is now southern Morocco. This species is assumed to be a close relative of Acastoides. The most conspicuous feature is the very long upcurved frontal medial spine, a bit like an avocet bill. It is the only known species in this genus.
The Devonian Jeffersonville Limestone is a mapped bedrock unit in Indiana and Kentucky. It is highly fossiliferous.
Bouleia is a genus of trilobites in the order Phacopida which existed during the lower Devonian in what is now Bolivia. It was described by Kozlowski in 1923, and the type species is B. dagincourti, which was originally described under the genus Phacops by Ulrich in 1892. It also contains the species B. sphaericeps, originally described by Kozlowski, also in 1923, as Dereimsia sphaericeps. The type locality was the Icla Formation in Padilla.
Coltraneia is a genus of trilobite, that lived during the upper Emsian and lower Eifelian, and has been found in Algeria, France, Germany, Morocco and Spain.
The Milwaukee Formation is a fossil-bearing geological formation of Middle Devonian age in Milwaukee County, Wisconsin. It stands out for the exceptional diversity of its fossil biota. Included are many kinds of marine protists, invertebrates, and fishes, as well as early trees and giant fungi.
The Vireux-Molhain national nature reserve (RNN104) is a national nature reserve of geological and paleontological interest. It is located in the Pointe de Givet, department of Ardennes, on the border between France and Belgium. It covers an area of 1.82 ha. The site is known as Customs Wall as it is near an old customs post. This outcrop of Middle Devonian shale is notable for the quantity and good state of preservation of its fossils. Trilobites are well-represented.