Gunakadeit joseeae was named by Druckenmiller et al. (2020) [Small-bodied (estimated total length 75–90 cm) thalattosaurian possessing the following autapomorphies: extremely pointed rostrum; posteriorly inclined dorsal process of the jugal; temporal region much shorter than orbit; anterior dentary edentulous; elongate retroarticular process; dorsal, sacral and anterior caudal neural spines with acute dorsal margin; elongate and narrow sacral ribs with distal expansion less than one third rib length; numerous, extremely fine gastralia; tapered posterodorsal process of ilium; tibia preaxial margin strongly convex. Gunakadeit joseeae can further be diagnosed on the basis of the following unique character combinations: large external naris; jugal extending far anterior of orbital margin; presence of supratemporal fenestra; reduced cervical region with approximately four cervicals; lateral processes of interclavicle more than 3 times longer than the width of the posterior process; proximal end of humerus wider than distal end; proximodistally elongated reniform radius; posterodistal process of the ilium short; tibia and fibula less than half femoral length.]. It is not extant. Its type specimen is UAMES 23258, a skeleton (a nearly complete skeleton including the skull and most of the axial and appendicular skeleton; missing the distal two-thirds of the tail and the distal portion). Its type locality is Keku islands, which is in a Norian marine horizon in Alaska.