First record of the genus Diarthrodella Klie, 1949 (Copepoda, Harpacticoida, Paramesochridae) from the Mediterranean Sea, with description of a new species from Turkey

Both sexes of Diarthrodella ergeneae sp. nov. (Copepoda, Harpacticoida, Paramesochridae), which were collected from the intertidal zone of Kurtpinari Beach along the Mediterranean coast of Turkey, are described in detail. The new species is morphologically most similar to D. convexa Kunz, 1981; D. secunda secunda Kunz, 1954; and D. lancifera Kunz, 1981 according to the setal formula of the swimming legs, but D. ergeneae sp. nov. can easily be differentiated from D. convexa by the ratio of P1 exopod/enp-1, by the lack of an inner seta on P2 enp-2, and by the shape and armature of P5; from D. secunda s. str. by having a seta on the proximal segment of A2 exopod, P3 enp-2 with inner seta, and P3 enp-3 with 2 setae and by the armature and shape of P5 and squarish caudal rami; and from D. lancifera by having 6 setae on P1 exp-2 and squarish caudal rami that bear filiform terminal setae. A key to the species of Diarthrodella is given. Investigation of the previous literature has revealed that the genus Diarthrodella has not been reported from the Mediterranean Sea so far; hence, this is the first record of the genus from the Mediterranean Sea.