Homocyclops ater (Herrick, 1882)

Perbiche-Neves, Gilmar, Corgosinho, Paulo H. C., Previattelli, Daniel, Suárez-Morales, Eduardo, Nogueira, Marcos G. & da Rocha, and Carlos E. F., 2025, Catalogue for identification of the most common lacustrine and riverine cyclopoid copepod (Crustacea) species in plankton of La Plata Basin, South America, Zoologia (e 24023) 42, pp. 1-47 : 15

Homocyclops ater (Herrick, 1882)

Fig. 16

Diagnosis. Adult female, 1,730 µm in length excluding caudal setae. Broad and robust body. Maxilliped has few rows of spinules on the exopod ( Fig. 16A ). Genital double-somite 1.2 times wider than long ( Fig. 16B ). Seminal receptacle has lateral projections ( Fig. 16B ). Antennule is 17-segmented. P5 middle seta longer than the outer and inner setae ( Fig. 16C ). P4-endopod outer terminal spine 0.8–0.9 times the length of the segment ( Fig. 16D ).

Remarks. Species with wide geographic distribution and usually found in low numbers in zooplankton samples. Large-bodied copepod, often associated with aquatic macrophytes and littoral zones. In samples from macrophytes, several individuals were collected.

Figures

Figure 16. Homocyclops ater, female: (A) maxilliped; (B) genital double-somite; (C) P5; (D) P4-endopod terminal segment. Scale bars: 50 µm.