A new species of Bestiolina (Crustacea, Copepoda, Calanoida, Paracalanidae) from coastal waters of the Colombian Pacific, including a worldwide key for the identification of the species

Abstract. Plankton samples obtained from estuarine waters of the Colombian Pacific yielded adults specimens of an undescribed species of a paracalanid copepod of the genus Bestiolina. It most closely resembles two Asian species; B.sinica (Shen & Lee, 1966) from China and B.arabica (Ali, Al-Yamani & Prusova, 2007) from the Arabian Gulf. These three species share the absence of spinules on the posterior surfaces of exopod segments of legs 2, 3 and 4. Bestiolinasarae Dorado-Roncancio & Gaviria, sp. n. can be easily separated from B.sinica by the number of spinules on the anterior surface of endopod 2 of legs 2 and 3, and by the absence of spinules on the posterior surface of second endopod of leg 4. It can be distinguished from B.arabica by the presence of spinules on the posterior surface of endopod 2 of same legs (absent in B.arabica), and the size of spinules on the anterior surface of the same segments. The only other species known from the Americas, B.mexicana (Suárez-Morales & Almeyda-Artigas, 2016), can be distinguished from Bestiolinasarae Dorado-Roncancio & Gaviria, sp. n. by the presence of spinules on the posterior surface of the leg 2 first exopodal segment and the morphology of the mandible blade. The morphological and meristic differences to the eight known species of the genus are presented. An identification key to the species of Bestiolina is provided.