Currently, 14 species and one subspecies of Dictyoconus (Orbitolinidae) are included in the online data base (e.g., WoRMS), among 12 having been described from the Paleogene, mostly from Eocene limestones. A taxonomic reconsideration leads to a drastic reduction of species that can be well differentiated as separate taxa with distinct structural features observable in thin sections. This is due to synonymizations and the treatment of other forms as taxa inquirenda with disputed validity. The revision presented herein refers to four Eocene species that can be considered as valid with respect to modern taxonomic concepts: the type-species D. egyptiensis (Chapman), D. indicus Davies, D. daviesi Silvestri, and D. aydimi (Gallardo-Garcia and Serra-Kiel). The distinguishing features refer to the degree of the exoskeleton complexity as well as the organization of the megalospheric embryo in the former two. The geographic occurrences of Eocene Dictyoconus species associated with some other taxa such as the coskinolinids Pseudolituonella robineti Gallardo-García and Serra-Kiel or Coskinolina perpera Hottinger and Drobne exhibits a restriction to a confined bioprovince comprising northern and eastern Africa, the Middle East including SE Turkey (Arabian Plate) and western India. The previous assumption in the literature about the occurrence of Cushmania americana (Cushman) in Somalia can be confirmed challenging the exclusive separation of the America and Neotethys bioprovinces in Eocene times for larger agglutinated conical taxa.
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