Inventory of the specimens of the Class Crinoidea (Echinodermata) deposited at the Invertebrates collection at the Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”

: The invertebrate collection of the Museo Argentino de Ciencias Naturales “Bernardino Rivadavia” (MACN-In) is one of the most important in Latin America. It has more than 1411 type batches with ~90 type specimens of echinoderms. For the present study we analyzed 56 lots of crinoids from the MACN-In. We also checked and updated the identification, when necessary. Seven species belonging to 6 genera were identified; 23 specimens remain unidentified. The diversity of crinoids for Chile, Uruguay and Brazil and Antarctica is dis- cussed. The MACN-In has several lots of crinoids from different parts of the world and numerous specimens of the 2 representative species from Argentina, Isometra vivipara Mortensen, 1917 and Phrixometra nutrix (Mortensen, 1918). This is the first published inventory of crinoids from samples deposited at the MACN-In collection, which will be a useful tool for future studies regarding echinoderms, particularly crinoids.