Microstructural design of the stalk in the crinoid Seirocrinus supports its pseudoplanktonic lifestyle.

ABSTRACT: During geological history, some crinoids convergently deviated from a benthic lifestyle. Seirocrinus is an iconic example of a crinoid that adapted to a pseudoplanktonic mode of life by living attached to drift logs. While significant effort has been devoted to exploring its functional morphology and palaeoecology, little attention has been given to the microstructural design of its stalk. Here, we describe the stereom microstructure and internal architecture of the Seirocrinus stalk. We demonstrate that its stereom organization closely resembles that observed in extant benthic crinoids (isocrinids): coarse, irregular labyrinthic-like stereom is found in the interpetaloid zones, while the aligned, galleried stereom is extensively developed in the petaloid zones. We show that this galleried

SUBMITTER: Gorzelak P 

PROVIDER: S-EPMC12381209 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature