A new brittle star from the early Carboniferous of Poland and its implications on Paleozoic modern-type ophiuroid systematics

• Main Authors: Ben Thuy, Manfred Kutscher, Bartosz J. Płachno
• Format: Article
• Language: English
• Published: Institute of Paleobiology PAS 2015-12-01
• Series: Acta Palaeontologica Polonica
• Subjects: Echinodermata; Ophiuroidea; crown-group; evolution; Carboniferous; Tournaisian; Poland
• Online Access: http://www.app.pan.pl/archive/published/app60/app000932014.pdf

The fossil record of Paleozoic ophiuroids includes a number of forms which share striking similarities with modern relatives in terms of skeletal morphology. These so called modern-type Paleozoic ophiuroids yield an enormous potential for a better understanding of ophiuroid evolution, yet the scarcity of accurate and sufficiently detailed morphological descriptions available to date precludes any further-reaching assessments. Here, we describe an articulated ophiuroid specimen from the Late Tournaisian (early Carboniferous) of Czatkowice quarry, southern Poland, as a new species Aganaster jagiellonicus sp. nov. The good preservation of the specimen allowed for a morphological analysis at a level comparable to recent ophiuroid descriptions. It shows remarkable morphological similarities with extant former ophiolepidids Ophiomusium and Ophiosphalma. The new find thus contributes to a solid basis for future investigations on the position of the modern-type Paleozoic ophiuroid in the phylogeny of the class.