Nausithoe eumedusoides (Werner, 1974)

(Fig. 6: E–H)

Stephanoscyphus eumedusoides Werner, 1974: 439–461, figs 1–5.

Nausithoe eumedusoides — Jarms, 1990: 11.

Holotype ZMH C9797.

Material examined: Living polyps kept in laboratory cultures (from submarine caves in Mljet, Croatia, 2002; 26m depth; H. Zibrowius col.).

Diagnosis: medusoid—tetrameric form with no manubrium, can be hermaphroditic; polyp—solitary with single cusp closer to the base.

Description: Based on Werner (1970) and original description. Medusoid 1–1.5 mm in umbrella width and 1–1.2 mm in height; quasi-tetrameric; lack of manubrium; rhopalia with minimally developed sense organ; absence of coronal groove until the final moments of strobilation; no gastric filaments; reduced umbrella musculature with 4 thin longitudinal muscle strands; beating flagella on the epidermis; four gonads in total (eight merged in pairs), bean-shaped or oblong, with yellow to brown pigmentation; can be hermaphroditic (with even the production of both eggs and sperm cells at the same time in the same gonad) or single sexed. Polyp solitary; 22.2 mm in total length; 1–2 single cusp closer to the base (arranged vertically one above the other); produces 4–5 medusoids per strobilation.

Type locality: Submarine caves near Marseille, France.

Distribution: Marine caves probably of all Mediterranean (2–50 m depth).

Remarks: Only N. eumedusoides and N. racemosa have a medusoid described in their life cycle, but the polyps are extremely different from each other. N. eumedusoides is a solitary species while N. racemosa is colonial (and with significant soft body differences, e.g., oral disc, symbiosis with algae).