Ausichicrinites zelenskyyi, a fossil feather star (Crinoidea) from the Upper Jurassic of Africa was … [+]
Polish paleontologists named a 150-million-year-old feather star (order Comatulida) after Ukrainian President Volodymyr Zelenskyy.
The genus name Ausichicrinites refers to Prof. William I. Ausich, an expert on fossil crinoids, and the species name zelenskyyi honors President Zelenskyy for his “courage in defending a free Ukraine.”
The well-preserved and complete fossil was discovered in the Antalo Limestone Formation of Ethiopia and is the first Jurassic crinoid (a group of invertebrates also including starfish, brittle stars, sea urchins and sea cucumbers) ever found on the African continent. Ausichicrinites zelenskyyi belongs to a subgroup of crinoids with no living relatives.
Fossil feather stars are mostly known from highly disarticulated specimens. The skin of the living animal is covered with tiny ossicles made of calcium-carbonate, forming a protective yet flexible outer shell. But as the animal dies and the soft tissue decays, the ossicles and organs like the arms tend to fall apart. So the discovery of a nearly complete specimen is a rare event.
The fossil also shows signs of an old injury. The animal survived an attack, likely a failed predation attempt, but lost one of its ten arms. Modern crinoids are well known for their striking regenerative potential and can rapidly and completely regenerate lost arms. A. zelenskyyi shows signs of a regrowing arm and is the first example of regeneration documented in a fossil feather star.
Complete specimen of Ausichicrinites zelenskyyi showing regenerating arm parts.
The paper “Ausichicrinites zelenskyyi gen. et sp. nov., a first nearly complete feather star (Crinoidea) from the Upper Jurassic of Africa” is published in Royal Society Open Science (2022).
