Copula sivickisi (Stiasny 1926)

Description of adult medusae. Bell blunt, pyramidal (slightly wider at bell opening and slightly narrower at top compared to bell height), highly transparent, slightly brownish, with white nematocyst warts (Figures 2 A, H). Nematocyst warts scattered on bell from apex to velarium. Bell apex flattened with no horizontal constriction near top, with 4 adhesive pads used to attach themselves to substrates when resting. Adhesive pads transparent, almost invisible in live specimens, but slightly opaque and visible in preserved medusae (Figure 2 D). Bell height up to 12 mm, bell width ca. 14 mm wide (interpedalial distance).

Pedalium, single, flattened, slender knife blade-shaped, ca. ½ the bell height in length (Figure 2 F), situated in each interradial corner, with 3–7 broad, rectangular nematocyst bands on outer keel of pedalium, carrying single tentacle. Tentacles show typical striped pattern (also maintained in preserved specimens) of broad and thin bands of brightly purple (males) or brown-orange colour (males and females) and white nematocyst batteries (Figure 2 G). Pedalial canal with rounded knee bend without any angle, hook or thorn appended to the outer knee bend (Figure 2 F).

Rhopalium located inside rhopalial niche on each side of bell. Orifice vertical, longish keyhole-shaped with rounded closure at the top and being open at the bottom without any prominent covering scales (Figure 2 E), ca. 1/6 of bell height up from margin. Rhopalial horns thin and short, located above top end of rhopalial niche (Figure 2 E, arrows).

Velarium, containing 4 simple, broad velarial canals per quadrant (Figures 2 C, J). Four-lobed, cruciform manubrium, ca. 1/3 of bell height in length and connected to flat stomach; stomach communicates perradially with 4 gastric pouches leading into velar canals. Four horizontal, slightly concave gastric phacellae (Figure 2 D), each consist of ca. 40, simple, unbranched, vertically stacked gastric filaments. Gonads paired (hemigonads), separated by interradial septum, extending from stomach rim to upper third of the bell about manubrium level (Figure 2 H).