A remarkable illaenid trilobite from the Middle Ordovician of Morocco (original) (raw)
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Trilobites from the Upper Ordovician of Bou Nemrou - El Kaid Errami (Morocco)
Batalleria
Trilobites from the Izegguirene Formation (First Bani Group, Lower Caradoc, Upper Ordovician) of Bou Nemrou (El Kaid Errami, East of Anti-Atlas, Morocco) are described. These comprise the following taxa: Basilicus calzadai sp. nov., Placoparia sp., Eoharpes sp., Zeliszkella (Zeliszkella) velai sp. nov., Degamella sendinoae sp. nov., Uralichas hispanicus tardus (Vela & Corbacho, 2009) and Selenopeltis longispinus (Vela & Corbacho, 2009)
Giant Trilobites from Lower Ordovician of Morocco
2009
Two new species and two subspecies of giant trilobites (Asaphidae familiy) of the formation of "Schistes des Fezouata Superieurs" coming from Arenig (Lower Ordovician) of the Morocco are described. They are Ogyginus forteyi hammondi n. ssp.; Megistaspis (Ekeraspis) hammondi n. sp.; Megistaspis (Ekeraspis) hammondi forteyi n.ssp. and Basilicus (Basilicus) vidali n.sp. We will also show all the specimens of giasnt trilobites from Lower Ordovician of Morocco so far found, some already described by other authors, and other not desctibed yet.
Diverse and abundant trilobite faunas occur in several beds near the base of the section of the upper Emsian to Eifelian Timrhanrhart Formation exposed at Jbel Gara el Zguilma, south of Foum Zguid in Morocco. While trilobites occur throughout much of this section, they are exquisitely preserved and most diverse in the lowest (upper Emsian) portion. Several of the trilobite species are commercially available, but their taxonomy has never been formalized, and their field occurrence has not previously been described. Near the base of the section, two nodular argillaceous limestone beds contain highly diverse trilobite faunas, with many spectacular spiny forms. These include examples deviating from bilateral symmetry that are apparently unique in the Trilobita. Alpha diversity is high, with as many as 23 trilobite species in one bed. We suggest that these nodular beds represent thick, rapidly emplaced storm obrution deposits that underwent transport for a short distance before the trilobites came to rest in chaotic burial orientations. Calcareous nodule formation during early diagenesis protected the trilobites from compaction. Higher in the same section, in strata of Eifelian age, trilobite faunas are of lower diversity, and composed mainly of species of Phacops, Hollardops and Parahomalonotus, although one horizon has an alpha diversity of at least 9 species. Twenty three new species-level taxa include: Acastoides zguilmensis, Acastoides haddadi, Coltraneia effelesa, Cyphaspis agayuara, C. eberhardiei, C. hamidi, Diademaproetus mohamedi, Gerastos tuberculatus marocensis, Hollardops aithassainorum, Kayserops tamnrherta, Koneprusia dahmani, Leonaspis haddanei, L. spinicurva, Parahomalonotus calvus, Phacops granulops, P. lebesus, P. smoothops, Psychopyge hammerorum, Scabriscutellum hammadi, S. lahceni, Tropidocoryphe amuri, Walliserops hammii, and W. tridens. Cyphaspis new species A is known only from a single cephalon. "Sculptoproetus" new species A and "S." new species B are being named in another work that will appear in print after this work.
Well-preserved specimens of the phacopine trilobites Morocops Basse (= Barrandeops McKellar & Chatterton) and Adrisiops gen. nov. are recorded from upper Emsian strata in Morocco. Morocops is a problematic taxon; the close similarities of its stratigraphically youngest members to the earliest members of Geesops Struve are indicative of grade taxonomy. So far, Morocops is exclusively Gondwanan although potential congeners have been described from peri-Gondwana. One of the stratigraphically oldest species of Geesops occurs in the lower Eifelian of the French Ardennes (Laurussia). Its co-occurrence with pioneer " Bohemian " trilobites there suggests that faunal exchange between Laurussia and peri-Gondwanan terranes was unhindered at that time. New material of Morocops torkozensis (Schraut) is recorded; however, the type locality and horizon of this species remain uncertain. Adrisiops gen. nov. is erected to accommodate strongly vaulted, Gondwanan taxa that share a unique cephalic morphology inclusive of a short, but rather inflated glabella and ventrally deflected anterior border. New taxa are Morocops spinifer sp. nov. and Adrisiops weugi gen. et sp. nov. •
Complete, articulated crinoids from the Ordovician peri-Gondwanan margin are rare. Here, we describe a new species, Iocrinus africanus sp. nov., from the Darriwilian-age Taddrist Formation of Morocco. The anatomy of this species was studied using a combination of traditional palaeontological methods and non-destructive X-ray micro-tomography (micro-CT). This revealed critical features of the column, distal arms, and aboral cup, which were hidden in the surrounding rock and would have been inaccessible without the application of micro-CT. Iocrinus africanus sp. nov. is characterized by the presence of seven to thirteen tertibrachials, three in-line bifurcations per ray, and an anal sac that is predominantly unplated or very lightly plated. Iocrinus is a common genus in North America (Laurentia) and has also been reported fromthe United Kingdom(Avalonia) and Oman (middle east Gondwana). Together with Merocrinus, it represents one of the few geographically widespread crinoids during the Ordovician and serves to demonstrate that faunal exchanges between Laurentia and Gondwana occurred at this time. This study highlights the advantages of using both conventional and cutting-edge techniques (such as micro-CT) to describe the morphology of new fossil specimens.
A new iocrinid crinoid ( Disparida ) from the 1 Ordovician ( Darriwillian ) of Morocco
2015
Complete, articulated crinoids from the Ordovician peri-Gondwanan margin are rare. Here, we describe a new species, Iocrinus africanus sp. nov., from the Darriwilian-age Taddrist Formation of Morocco.The anatomy of this species was studied using a combination of traditional palaeontological methods and non-destructive X-ray micro-tomography (microCT). This revealed critical features of the column, distal arms, and aboral cup, which were hidden in the surrounding rock and would have been inaccessible without the application of micro-CT. Iocrinus africanus sp. nov. is characterized by the presence of seven to thirteen tertibrachials, three in-line bifurcations per ray, and an anal sac that is predominantly unplated or very lightly plated. Iocrinus is a common genus in North America (Laurentia) and has also been reported from the United Kingdom (Avalonia) and Oman (middle east Gondwana). Together with Merocrinus, it represents one of the few geographically widespread crinoids during th...
Geologica Belgica, 2022
A group of asteropygine trilobites with 10 thoracic segments from the lower Emsian to lowermost Eifelian of western Europe and northwest Africa is deemed monophyletic. Available names for this clade are Hollardops Morzadec, 1997, Philipsmithiana Lieberman & Kloc, 1997, Modellops Lieberman & Kloc, 1997 and Pennarbedops Bignon & Crônier, 2013, the first of which has priority. Well-preserved Hollardops specimens from southern Morocco have revealed previously undescribed details of the mineralised exoskeleton that are interpreted here as coaptative and sensory devices. It is proposed that Hollardops, like many other asteropygines, practised a dual mode of coaptation: fully locked enrolment was alternated with a retracted pygidium, allowing temporary influx of oxygenated seawater and excretion through slits between the pygidial lappets. This putative ‘breathing device’ enabled the trilobite to remain enrolled for a longer period of time while maintaining vital body functions. A poor understanding of the problematic type species of Hollardops, H. mesocristatus (Le Maître, 1952), has clouded actual diversity in Algeria and Morocco. Hollardops klugi sp. nov. is the oldest known member of the genus and extends its confirmed stratigraphic range into the lower Emsian. Two species, H. kyriarchos sp. nov. and H. multatuli sp. nov., are recorded from just above the base of the upper Emsian. Additionally, H. angustifrons sp. nov., H. luscus sp. nov. and the first well-preserved specimens of H. boudibensis Morzadec, 2001 are recorded from the upper Emsian. The types of H. hyfinkeli (Lieberman & Kloc, 1997) and H. burtandmimiae (Lieberman & Kloc, 1997) are refigured and original species concepts reiterated. Feruminops Haas, 1968, including its junior subjective synonym Morzadecops Bignon & Crônier, 2013, from the lower Emsian of Morocco and Türkiye, may comprise the sister group of Hollardops. Additionally, the enrolment strategies and systematics of several other members of Asteropyginae are discussed. Platykardiapyge gen. nov. (type species: Metacanthina maderensis Morzadec, 2001) is erected for a group of Pragian–early Emsian asteropygines from Morocco, Spain and Türkiye with a widely heart-shaped pygidium and comparatively many pygidial pleurae, among other features. Bignonops gen. nov. (type species: Kayserops tamnrhertus Chatterton et al., 2006) is erected for some species previously included in Gandlops Bignon & Crônier, 2013. Minicryphaeus suavius sp. nov. is described from the lower Emsian of Morocco. The identity and generic affinity of the oldest known asteropygine, Ganetops gdoumontensis (Asselberghs, 1930) from the Pridolian of Belgium, are discussed.
First African oryctocephalid trilobites from the Lower–Middle Cambrian boundary interval
Palaeoworld, 2006
Oryctocephalid trilobites from Lower Middle Cambrian strata of the eastern Anti-Atlas, Morocco, are the first described Oryctocephalidae known from Africa. They represent the new genus and species Shergoldiella vincenti. However, a similar species was earlier described as Tonkinella sequei Liñán et Gozalo, 1999, from coeval lower Middle Cambrian strata of the Iberian Chains, northern Spain. This Iberian species is imperfectly preserved and assigned herein to Shergoldiella with reservations. If this assignment is correct, it would reinforce earlier suggested correlations between Morocco and Spain. Nevertheless, Shergoldiella suggests a morphocline from a typical oryctocephalid-type morphology towards the Tonkinella-type morphology. Close similarity with Ovatoryctocara ovata suggests a similar stratigraphic position in accordance with earlier suggested intercontinental correlations.