Paracornus, Malinky & Skovsted, 2004

Malinky, John M. & Skovsted, Christian B., 2004, Hyoliths and small shelly fossils from the Lower Cambrian of North-East Greenland, Acta Palaeontologica Polonica 49 (4), pp. 551-578 : 557

Genus Paracornus nov.

Type species: P. poulseni gen. et sp. nov.

Etymology: From Greek para, by, close to, and the generic name Microcornus .

Diagnosis.—Hyolithid having small apical angle and therefore narrow conch with gradual increase in apical angle beginning at approximately half the distance between apex and aperture; ornament on dorsum consist of rows of low rounded knobs that follow pattern of growth lines.

Remarks.—The change in apical angle and unusual ornament on the dorsum separate this form from all other Lower Cambrian hyolithids. The former trait is known from one species of Parakorilites He and Pei, in He et al.1984 from the Meischucunian of South China, and from Tizilites Marek, Malinky, and Geyer, 1997 from the Middle Cambrian of Morocco. In the former, the transformation from smaller to larger apical angle is more subtle and occurs much closer to the aperture than in Paracornus . In contrast, the change in Tizilites is far more abrupt and the resulting flaring of the aperture more pronounced. The rows of knobs that constitute the ornament on Paracornus are unknown in any other hyolithid. The protoconch of Paracornus is unknown at present, although should this genus prove to have a bulbous protoconch similar to Microcornus Mambetov, 1972 or Parkula Bengtson, 1990a , the change in angle and ornamentation would still suffice to separate it from those genera.

Stratigraphic range and distribution.—Lower Cambrian, North−East Greenland.