Linko, 1913
Short Description:
Jaschnovia tolli is an aetideid calanoid copepod known after both sexes (female 2.15-2.25 mm and male 2.10-2.15 mm in length) from coastal Siberian seas, very probably benthopelagic species.
Taxonomic Description:
Female. Total length 2.15-2.25 mm (after Jaschnov (1947) 2.50 mm). Cephalothorax about 4 times longer than abdomen. Posterior Th5 corners prolonged and pointed, reaching the midlength of genital segment. A1 reaching the midlength of genital segment. Ri2 A2 external lobe with 6 setae. Ri Mx1 with 16 setae. Oral parts and P1-P4 typical of the genus.
Male. Total length 2.10-2.15 mm (after Jaschnov (1947) 2.20 mm). Cephalothorax about 2.7 times longer than abdomen. Th5 posterior corners rounded (lateral view), pointed and curved externally when looking dorsally. A1 reaching the posterior border of genital segment. Oral parts in comparison with that in female rudimentary. P1-P4 as in female, but the spinulation of P4 with surface spinules weaker. P5 typical of the genus.
Vertical distribution:
The species may be found under desalination. Adult specimens occurred during the end of September and in October in the East Siberian Sea and in the Laptev Sea (Jaschnov, 1947). The majority of specimens found in September in the White Sea in the near bottom plankton tows obtained with Beyer net (Markhaseva, 1996). Very possible that at some stages of its life cycle the species is connected with near bottom layers.
Geographical distribution:
The species is widespread in coastal Siberian seas: the Kara Sea, Laptev, East Siberian and Chuckchee Seas, and in the Baffin Bay and the White Sea. There are findings in the Barents Sea (Zelikman, 1961), and data on recordings outside Arctic Basin limits in the Sea of Okhotsk (Brodsky, 1957).
Type locality: The East Siberian Sea near the Novosibirsk Islands (Linko, 1913).
Material examined:
2 females and 2 males from sample 459 and numbers of specimens of both sexes in not catalogued material obtained in the White Sea. See examined samples module.