Salacia bidentata Watson, 2000

Hydrorhiza reptant on substrate, stems monosiphonic, straight, proximal athecate region long, tubiform, perisarc smooth, moderately thick, ending in a strong hinge joint. Stem hydrothecate above joint, hydrothecae biseriate, opposite, proximal internodes with a pair of hydrothecae, succeeding internodes bearing two to four pairs of hydrothecae, nodes transverse to V-shaped, infrathecal segment immediately above node variable in length, others segments short.

Hydrothecal pairs laterally separated in proximal stem region, adjoining walls becoming fused in distal part of stem. Hydrothecae tubular, narrowing behind margin, floor curved to straight, a small knot of perisarc at base of adcauline wall; adnate adcauline wall straight to slightly convex, free wall about one quarter length of adnate part, curved upwards to margin, a small submarginal plug of perisarc projecting into hydrotheca; proximal abcauline wall straight to slightly concave, curvature increasing at flexure, a large hook-shaped or triangular submarginal shelf in bend projecting into hydrotheca. Margin with two blunt, wing-shaped lateral cusps, perisarc very thin, remnants of a thin abcauline opercular flap inside many hydrothecae.

Hydranths well preserved, without caecum, deeply withdrawn into hydrotheca, body closely transversely wrinkled, approximately eight tentacles with distinct rings of nematocysts.

Colour: Pale transparent yellow (preserved material).