Morphology of the Nauplii and Duration of Naupliar Development of the Black Sea Alien Species Oithona davisae Ferrari and Orsi, 1984 (Copepoda: Cyclopoida) in Laboratory Culture

The paper presents descriptions, original drawings and digital photos, and also the key for identifying naupliar stages of recent invader species in the Black Sea Oithona davisae (Copepoda: Cyclopoida). Nauplii were taken from a laboratory culture originating from the offspring of O. davisae females selected from living zooplankton sampled in Sevastopol Bay. Copepods were reared under natural illumination, temperature of 21 ± 2°C, and feeding with cryptophyte culture IBSS-CrPr54 (ESD = 10.9 ± 1.4 μm) (mean concentration constituted 6 × 10 3 cells mL –1 ; 0.7 μg C mL –1 ). The duration of the development from the first naupliar stage (N1) to the first copepodite (C1) stage was 5.3 ± 0.7 days (1 day for N1–N3, 1 day for N3–N4, and 3.3 days for N4–C1).