Emendation of the foraminiferal genus Cribrostomoides Cushman, 1910, and its taxonomic implications

Abstract

Abstract. A review of the taxonomic history of the agglutinated (benthonic) foraminiferal genus Cribrostomoides Cushman, 1910 reveals much confusion concerning its type species, coiling mode and apertural characteristics. We believe the originally designated type species of Cribrostomoides Cushman, 1910, C. bradyi Cushman, 1910, to be no more than varietally (i.e. infra-subspecifically) distinct from, and therefore a junior synonym of, Haplophragmoides subglobosus Cushman, 1910. The coiling of Cribrostomoides, as typified by C. subglobosus (Cushman, 1910), is in the form of an involute streptospire characterised by a repeated alternation in axis. The aperture of the genus is equatorially or asymmetrically placed and interio-areal and single (in megalospheric and juvenile microspheric specimens) to areal and multiple (in microspheric adults). In order to stabilise the concept of Cribrostomoides, we have designated lectotypes for both C. bradyi and H. subglobosus, and have also emended the generic diagnosis of Loeblich and Tappan (1987). Criteria for the discrimination of Cribrostomoides emend, herein and allied genera are tabulated.