Crinoid

Halocrinites inflatus

• Devonian
• Laskowa Góra Beds
• Laskowa Góra Quarry, Kielce area, Holy Cross Mountains, Poland

Size: 4.7 cm crown

Jan Bohatý has identified this specimen as Halocrinites inflatus (Schultze 1866).

The cupressocrinitids are a higly distinctive family of Devonian crinoids found in Europe and Africa but not North America. They are characterized by robust, uniserial unbranched arms comprised of a low number of hyperpinnulated brachials. Especially unusual are the thin and wide first primibrachials, so much so that at a glance they may be passed over as simply a sharp rim around the top of the calyx.

Cupressocrinitid classification has historically been complex and confusing, but recent work has revised and standardized this family, distinguishing Halocrinites from Cupressocrinites on the basis of an anatomical feature known as the "exoplacoid layer" (Bohatý 2005, Bohatý & Ausich 2021). Essentially, cupressocrinitids with a multilayered external surface akin to growth lines parallel to the plate edges (formally called a "multilamellar exoplacoid layer") are assigned to the genus Halocrinites. This specimen is an example of Halocrinites inflatus, which true to its specific name is characterized by strongly inflated/bulbous brachials that give the arms a "beads on a string" appearance. It also preserves the multilamellar exoplacoid layer in great detail.