The lectotype of Spiroplecta rosula Ehrenberg, 1854 – the type species of Bolivinopsis Yakovlev, 1891 (Foraminifera)

Abstract. INTRODUCTION

The Ehrenberg collection of microfossils in the Natural History Museum, Berlin contains the original reference material for a single genus of agglutinated foraminifera – Bolivinopsis Yakovlev, 1891. Among the foraminiferal specimens preserved in the collection, a single specimen was selected and illustrated by Ehrenberg (1854) as Spiroplecta rosula. This species was subsequently designated by Kisselman (1964) as the senior synonym of Bolivinopsis capitata Yakovlev, 1891, making it the type species of Bolivinopsis by virtue of synonymy. According to Kisselman (1964), the type specimens of B. capitata were deposited in the Central Geological Museum in St Petersburg, and were lost during the war. Indeed, the name B. capitata is not used in the Soviet literature, and such forms are consistently attributed to B. rosula. As part of the work undertaken for a Catalogue of Agglutinated Foraminiferal Genera, we undertook a search of the Ehrenberg Collection in order to establish the status of the type specimen(s) of Spiroplecta rosula.

MATERIAL AND METHODS

The Ehrenberg collection of microfossils at the Museum für Naturkunde in Berlin consists of innumerable specimens embedded in Canada Balsam mounted on small mica disks that served as microscope slides. Small paper rings pressed onto the surface of the disks were used by Ehrenberg to mark specimens of importance, such as illustrated in Ehrenberg’s (1854) book Mikrogeologie. A catalogue of the collection was compiled originally by Ehrenberg’s daughter Clara and has been supplemented by new collection databases. We used these sources to locate and examine all the micas from the . . .