This paper is the fourth in a continuing series describing Late Cretaceous echinoids from the United Arab Emirates (Ali, 1989, 1990, in press). A single semi-spherical Arbaciidae was discovered while I was preparing my earlier paper on additional echinoids of Gebel El Rowdah. This specimen resembled Codiopsis L. Agassiz (1840), but differs in having the ambulacral and interambulacral tubercles developed throughout the adapical and adoral sides. The ambulacral structure in the new genus is also unique among arbaciids. Therefore, the specimen is here placed in a new genus, having been omitted from previous papers because of the paucity of the material. Recently, during a field trip with students of the Geology Department, U.A.E. University, to the same location visited in December 1990, an additional 18 specimens were collected. These provide the basis for the present description of a new genus.

Phylloid (leaf-shaped) fossil algae are common constituents in sedimentary rocks of Late Pennsylvanian through Early Permian age in the Midcontinent, U.S.A., commonly producing porous algal-rich bioherms that may be prolific petroleum reservoir rocks. During the course of re-evaluating the paleontological character of these fossil algae in Kansas, remarkably well-preserved codiacean algae were found in an oncolitic nodule in the Wakarusa Limestone Member of the Bern Limestone (Virgilian) in Lyon County, Kansas. Although this is the locality and stratigraphic bed from which the genotype Anchicodium funile Johnson, 1946, was collected, the new alga is not of that genus, but occurs with specimens of Anchicodium.