Abstract

“Asturicystis” havliceki Fatka and Kordule 2001 from the middle Cambrian of Bohemia is re-described based on its type material. Several features, including the extension of the food grooves and presence of ventral swellings suggest “Asturicystis” havliceki does not belong to Asturicystis, and is placed in the new genus Bohemiacinctus nov. To ascertain the phylogenetic position of Bohemiacinctus havliceki, we conducted Bayesian fossil tip-dating and parsimony-based phylogenetic analyses of 23 species spanning all major groups of cinctan higher taxa. Results indicate a high degree of congruence between tree topologies recovered by both tip-dated and parsimony-based analyses. Both methods indicate B. havliceki is phylogenetically distant from Asturicystis and is most likely an early representative of the family Sucocystidae. Overall, our phylogeny is broadly similar to previous estimates of cinctan relationships, including a more conventional phylogenetic position of controversial taxa like Protocinctus. These results point to the sensitivity of small clades like cinctans to taxon sampling effects, and highlight the importance of taxonomy and accurate morphological character descriptions in phylogenetic analyses of fossil taxa.