Middle Devonian brachiopods from the southern Maїder (eastern Anti-Atlas, Morocco) (original) (raw)

2013, Annales Societatis Geologorum Poloniae

Ab stract: Sixty-two Mid dle De vo nian brachio pod spe cies are de scribed on the ba sis of >1300 speci mens from the Tabou ma khloõf For ma tion (and sub or di nately proba bly also from the top of the El Ot fal For ma tion) at Ma-dÀne el Mrakib (mid dle to late Eife lian or early Giv etian?), Af er dou el Mrakib (late Eife lian to mid dle Giv etian), and Guelb el Ma harch (early Giv etian) on the south ern edge of the MaÎder Syn cline (east ern Anti-Atlas, Morocco). Rep re sen ta tives of Cra niida (2 taxa), Stro phomen ida (5), Pro duc tida (2), Or tho tet ida (2), Or thida (5), Pen tame rida (5), Rhyn chonel lida (9), Atrypida (14), Athy ridida (7), Spirif erida (9), and Spirif er inida (2) are pres ent. The fauna is domi nated quan ti ta tively by the Atrypida (24% of taxa, about the half of speci mens, and the com mon est spe cies Atry paria dis persa mak ing up about 13% of the ma te rial); the Rhyn chonel lida (16% of taxa, about one-sixth of speci mens) are the sec ond larg est or der. A new ge nus of the fam ily Pug naci dae (or der Rhynchonel lida), Pau linaer hynchia, is pro posed with the type spe cies P. pau li nae gen. et sp. nov. from Ma harch; it is clos est to Pug nax, from which it dif fers in dis tinct costa tion, lack of a dor sal sep tum and sep talium, and ru di mentary den tal plates. Desquama tia (D.) de serti sp. nov., a large and finely co state rep re sen ta tive of the ge nus, is de scribed also from Ma harch. An tirhyn chonella and Glosshy po thy ri dina are re ported for the first time or confirmed to be pres ent in the Giv etian. Forty (pos si bly up to 46) spe cies (71 or pos si bly up to 82% of the taxa iden ti fied at the spe cies level) are pres ent also in ei ther Eifel (Ger many) or the Holy Cross Moun tains (Po land). Such a high ra tio of spe cies in com mon at tests to un con strained fau nal ex changes among ben thic fau nas be tween the north ern and south ern shores of the Varis can Sea dur ing the Mid dle De vo nian. This fa vours the palaeo geographic hy pothe sis of a nar row Varis can Sea.