Late Albian cal car e ous dinocysts and calcitarchs re cord linked to en vi ron men tal changes dur ing the fi nal phase of OAE 1d -a case study from the Tatra Moun tains, Cen tral West ern Carpathians Borza) and Cadosina oraviensis Borza, oc cur spo rad i cally in the as sem blages. Both forms rep re sent the calcitarch group, which as sem bled calcispheres of un known tax o nomic af fin ity. The cal car e ous dinocyst and calcitarch di ver sity is low to mod er ate, com pared to the gen eral spe cies rich ness known from Late Albian as sem blages in other West ern Tethyan sec tions. This is in ter preted as a re sult of nu tri ent in put fluc tu a tions due to changes in the cir cu la tion pat tern of sur face and in ter me di ate wa ters. The changes in the P. sphaerica/P. ovalis ra tio along the Up per Albian sec tion are here cor re lated with short-term (third-or der) sea level fluc tu a tions in clud ing transgressive and re gres sive events and a highstand. Pelletization pro cesses might have influ enced cyst abun dance on the sea floor, es pe cially dur ing pe ri ods with oligotrophic sur face wa ters.Key words: cal car e ous dinocysts, calcitarchs, nu tri ent in put and sea level fluc tu a tions, Up per Albian, OAE 1d, Tatra Mountains.