Holotype, NMV F171356, infertile colony of 20 hydrothecae on mussel shell, depth 1 m. Clifton Springs boat harbour, Port Philip, Victoria, Australia. Material examined alive, initially preserved in 4% formalin and later transferred to 70% ethanol.
The species is named for its tall hydranth.
Colony stolonal, hydrorhiza reticulate, stolons tubular, weakly rugose; pedicellate hydrothecae borne at intervals along stolon.
Hydrotheca small, weakly conical to cylindrical, borne on a short indistinct pedicel with three or four basal twists; body of hydrotheca smooth to faintly rugose, margin circular with slightly thickened rim, operculum of c. 10 triangular flaps meeting apically, a distinct crease-line around margin, opercular remnants drawn deeply inside the margin of some younger hydrothecae.
Hydranth tubular, extensile and very long, a single whorl of c. 16 long moniliform tentacles with whorls of nematocysts held out in an amphicoronate pattern below a flat domed hypostome; no true intertentacular web but a ring of small birefringent granules between the bases of tentacles
Cnidome comprising one class of microbasic mastigophore in tentacles, capsule lenticular, 8–10 x 2.5–3.5 μm, shaft moderately long, tubule very long.
Perisarc of hydrorhiza and hydrotheca very thin, pale brown in colour
Colour: Perisarc pale brown, body of hydranth and tentacles colourless, transparent.
Victoria, Australia.
Subtidal, epizoic on benthic invertebrates.