First Korean Records and Morphological Comparison of Tozeuma armatum and Tozeuma lanceolate (Decapoda, Caridea, Hippolytidae)

Three female specimens of the caridean shrimp genus Tozeuma, collected off Jeju Island in 2003, 2004, and 2019, are documented as the first Korean records of T. armatum Paulson, 1875 and T. lanceolatum Stimpson, 1860. One specimen is identified as T. armatum based on a rostrum 1.67 times the carapace length and a single recurved median tooth at the posterior end of the third abdominal carina. Two specimens are identified as T. lanceolatum based on the combination of long preserved rostra, each exceeding 2.1 times the carapace length, and a tridentate posterior margin of the third abdominal carina. Both specimens of T. lanceolatum have damaged rostral tips; their preserved rostral proportions therefore represent minimum values. Morphological descriptions, illustrations, and a key to the three species of Tozeuma recorded from Korea are provided. The applicability and limitations of established diagnostic characters are discussed. These historical specimens document previously unreported occurrences in Korean waters, without establishing recent range expansion or resolving the species boundaries between the two nominal species.