|
Harpetida
Harpetida is one of the eleven orders of the extinct arthropod class Trilobita. The first harpetid trilobites appear in the Upper Cambrian, and the last species die out at the end of the Devonian period. Harpetid trilobites are characterized among trilobites by bearing a comparatively large, semicircular brim around the cephalon (head) which is often perforated by small pores. This brim is thought to serve as a filter-feeding apparatus. The brim stretches backward on either side of the cephalon (head) and typically has a pronounced suture along the outside. The compound eyes are typically reduced to small tubercles, though they have strong ridges stretching to the glabella (central region of the cephalon). They also typically have 12 or more thoracic segments. The pygidia are usually small. The families of Harpetida were formerly included in the order Ptychopariida, but were recently given their own order (Ebach & McNamara 2002). The subclass Librostoma was erected in 199 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Entomaspis
''Entomaspis'' is an extinct genus of harpetid trilobite from Upper Cambrian to Early Ordovician marine strata of the United States. Species are typified by their proportionally large, vaulted, croissant-shaped or bonnet-shaped cephalons that have the cheeks freed to become elongated, curved librigenial spines, and by their comparatively large, crescent-shaped eyes (in comparison with other eyed harpetids). Species ''E. bridgei'' ''E. bridgei'' is a species found in marine strata of Missouri. ''E. clarki'' ''E. clarki'' is a species found in Lower Ordovician marine strata of Vermont.Shaw, Alan B. "Paleontology of Northwestern Vermont. XII. Fossils from the Ordovician Highgate Formation." Journal of Paleontology (1966): 1312-1330. ''E. radiata'' ''E. radiata'' is the type species, and is found in Uppermost Cambrian and Lowermost Ordovician marine strata of Utah. It coexisted sympatrically In biology, two related species or populations are considered sympatric when ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hibbertia (trilobite)
''Hibbertia'' is a genus of trilobites. A new species, ''H. aodiensis'', was described from the late Ordovician of China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ... by Dong-Chan Lee in 2012. References Harpetida Ordovician trilobites of Asia {{harpetida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morocco
Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to the east, and the disputed territory of Western Sahara to the south. Mauritania lies to the south of Western Sahara. Morocco also claims the Spanish exclaves of Ceuta, Melilla and Peñón de Vélez de la Gomera, and several small Spanish-controlled islands off its coast. It spans an area of or , with a population of roughly 37 million. Its official and predominant religion is Islam, and the official languages are Arabic and Berber; the Moroccan dialect of Arabic and French are also widely spoken. Moroccan identity and culture is a mix of Arab, Berber, and European cultures. Its capital is Rabat, while its largest city is Casablanca. In a region inhabited since the Paleolithic Era over 300,000 years ago, the first Moroccan s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |