ABSTRACT: Pseudorhapydionina moulladei Pêcheux 1995 from the Paleocene of Mexico is taxonomically revised herein. Due to the presence of a bi- or tri-serial growth instead of planispiral juvenile stage, the species cannot be included in Pseudorhapydionina De Castro. Instead, it is assigned to Serrakielina Schlagintweit and Rashidi becoming S. moulladei (Pecheux 1995) comb. nov. The differences to the type-species S. chahtorshiana (Paleocene of Iran) bear on the thickness of septula, general dimensions, number of branches in the stellate foramina, which result in S. moulladei as being smaller than S. chahtorshiana, but having thicker setptula especially in the adult chambers. Based on our observations and studying the records available from the literature, it is concluded that Serrakielina moulladei (Pecheux 1995) comb. nov. and S. chahtorshiana characterize the Paleocene Caribbean and Central Tethys bioprovinces, respectively. Further records of Serrakielina sp. from the literature have been found in the Paleocene of Spain and Guatemala.

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