. Early Llandovery crinoids and stelleroids from the Cataract Group (Lower Silurian) in southern Ontario, Canada. Crinoidea, Fossil; Starfishes, Fossil; Paleontology; Paleontology. Class Crinoidea Miller, 1821 Subclass Camerata Wachsmuth and Springer, 1885 Order Monobathrida Moore and Laudon, 1943 Superfamily Patelliocrinacea Angelin, 1878 Family Patelliocrinidae Angelin, 1878 Kylixocrinus gen. nov. TYPE SPECIES Kylixocrinus latus sp. nov. ETYMOLOGY From the Greek kylix—a shallow cup—in reference to the low, bowl-like shape of the cup of this genus, and from the Greek krinon—lily. DIAGNOSIS Mo
. Early Llandovery crinoids and stelleroids from the Cataract Group (Lower Silurian) in southern Ontario, Canada. Crinoidea, Fossil; Starfishes, Fossil; Paleontology; Paleontology. Class Crinoidea Miller, 1821 Subclass Camerata Wachsmuth and Springer, 1885 Order Monobathrida Moore and Laudon, 1943 Superfamily Patelliocrinacea Angelin, 1878 Family Patelliocrinidae Angelin, 1878 Kylixocrinus gen. nov. TYPE SPECIES Kylixocrinus latus sp. nov. ETYMOLOGY From the Greek kylix—a shallow cup—in reference to the low, bowl-like shape of the cup of this genus, and from the Greek krinon—lily. DIAGNOSIS Monotypic patelliocrinid with low, bowl-shaped aboral cup. Median ray ridges present. Interrays not depressed; CD-interray much wider than others. Radials largest plates in cup. Primibrachials two; fixed secundibrachials two or three. First interprimibrachial hexagonal, supporting two smaller plates. Primanal large, subequal, septagonal or octagonal, typically in contact with first primibrachial of D-ray, and bounded on right by smaller anal plate. Arms ten, pinnulate, biserial. DISCUSSION Kylixocrinus gen. nov. is closely related toMacrostylocri- nus (see p. 16 for a discussion of Macrostylocrinus). The two genera differ primarily in the CD-interray area (Text-fig. 5). There are two anal plates in the first range on Kylixocrinus, in contrast to only one plate (the primanal) on many species of Macrostylocrinus. The primanal of Kylixocrinus is large and approximately the same size as the underlying radials whereas the primanal of Macrosty- locrinus is typically much smaller. The primanal of Kylixocrinus is typically in lateral contact with the first primibrachial of the D-ray, but it is separated from the corresponding plate in the C-ray by a smaller anal plate that is supported by a septagonal radial. The primanal of Macrostylocrinus, in contrast, is commonly in lateral contact with the first primibrachials of the C- and D-rays, and its underlying radials are typically hexa
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Keywords: ., bookcentury1900, bookd, bookleafnumber18, booksubjectpaleontology
