Arenopontia subterranea Kunz, 1937 sensu Arlt (1983)

Sak, Serdar, Karaytuğ, Süphan & Huys, Rony, 2024, A revision of the genus Arenopontia Kunz, 1937 (Copepoda, Harpacticoida, Arenopontiidae), including the description of five new species, Zootaxa 5433 (1), pp. 1-50 : 42

Arenopontia subterranea Kunz, 1937 sensu Arlt (1983)

Arlt (1983: 73–74; Fig. 17 ) collected a single female (body length 310 μm) from fine sand at 13 m depth, east of Darss Sill in the Baltic Sea ( Germany) and provided a concise illustrated description. Based on his figures it appears that he was dealing with an aberrant specimen, displaying five setae on one member of the fifth pair of legs and three setae (the outer basal one definitely lacking) on the other side. His statement that “... the terminal segment of enp P1 had only normal setae and no surface seta...” is puzzling since his illustration shows exactly the same condition as in other members of the genus. Assuming Arlt’s (1983) drawing of the P1 endopod is correct there is a hint that his female specimen belongs to Group II. The author also mislabelled the P3 as the P2 and showed two (!) setae on the antennary exopod. The caudal ramus appears to have a raised spinular row on its dorsal surface and setae VII is not foliaceous. The P1 endopod is considerably longer than in Kunz’s (1937) type material, approaching the condition of A. syltensis sp. nov. It is highly likely that Arlt (1983) has either illustrated the latter or another closely related species, casting further doubt on the validity of other Baltic records of A. subterranea . This is the only illustrated mesohaline record of the genus.

Figures

FIGURE 17. Arenopontia syltensis sp. nov.: (A) habitus ♀, lateral; (B) habitus ♀, dorsal; (C) posterior part of anal somite and left caudal ramus ♂, lateral; (D) posterior part of anal somite and right caudal ramus ♀, lateral