Symplectoscyphus paulensis Stechow, 1923

Colonies irregularly and profusely branched more or less in one plane.

Stem of tallest colony 3 mm wide above hydrorhiza, heavily fascicled, stolons growing upwards to become polysiphonic tubes of stem. Branches (hydrocladia) to 30 mm long, slender, polysiphonic tubes often extending a short distance along branch. Branches thereafter monosiphonic (hydrocladia), branched subdichotomously several times at c. 120°, a hydrotheca in each dichotomy. Hydrocladial internodes long, cylindrical, widening a little below hydrotheca, perisarc smooth, sometimes undulated, internode widening distally; nodes distinct, oblique to almost transverse, marked by a narrowing of perisarc, frequently a tumescence above or below node; a node on each side of hydrotheca in dichotomy.

Hydrothecae alternate, distant, given off almost in one plane just below node at an angle of c. 80° to internodal axis, almost cylindrical, narrowing very slightly to margin, walls smooth, adcauline wall gently convex, adnate adcauline wall short, becoming free opposite or just below node, free wall convex to almost straight, but less curved than adnate part, at least twice length of adnate part; abcauline wall slightly concave, curving smoothly outward, contiguous with internode. Hydrotheca widest at junction of adnate and free adcauline wall, narrowing a little to margin, floor narrow, flat, a minor thickening of perisarc at base of adcauline wall, a triangular foramen and thinning of perisarc in internode beneath floor. Margin with 3 low, equidistant cusps separated by broad, rather shallow embayments; margin often with numerous fine replications, operculum of 3 triangular valves. Perisarc of hydrotheca thin, slightly thicker at marginal replications, operculum thin.

Hydranth with c. 24 tentacles, a strand of tissue attaching hydranth to hydrotheca about one-third distance up adcauline wall.

Colour: Pale yellow-brown.