Sertularella splendida sp. nov.

urn:lsid:zoobank.org:act: 900C4D1A-64A7-402E-B695-3BF396F18579

Fig. 9 N–P; Table 6

Diagnosis

Sertularella with lightly fascicled, irregularly and sparsely branched stems; internodes moderately long, geniculate; hydrothecae exceedingly long, gradually narrowing slightly from base to aperture, adnate for ¼ or less, free adaxial side with 7–9 transverse ridges, an intrathecal cusp abaxially. Gonothecae unknown.

Etymology

From the Latin adjective splendĭdo, -a, -um (splendeo), originally meaning brilliant, dazzling, or glowing, but subsequently retained as “splendid” or “magnificent” in modern usage, to denote the beautiful appearance displayed by this species.

Material examined

Holotype

BATHUS 3: Stn. DW809, a 23 mm high, sterile stem fragment devoid of its basal part, but carrying a short, distally broken side branch; an accessory tube on the stem (MNHN-IK-2012-16587).

Paratypes

BATHUS 3: Stn. DW809, four sterile stems or fragments, 7–14 mm high; side branches occur in two specimens; accessory tubes also present in two specimens (MNHN-IK-2012-16588).

Description

Colonies up to 23 mm high, arising from rhizoid stolon firmly attached to substrate; stems either lightly fascicled basally (with 1–2 auxiliary tubes) or monosiphonic; basal part of varied length, ahydrothecate, with smooth, thick perisarc; above, stem divided into regular internodes by means of slightly oblique nodes sloping in alternate directions; internodes geniculate, moderately long, widening gradually towards distal end, where they bear a hydrotheca. Side branches, when present, originating from below a stem hydrotheca, either laterally, or slightly in front of colony; first internode longer than subsequent ones, constricted basally at insertion on stem; remainder of side branch with same structure as stem. Hydrothecae alternate on stem and branches, originating at an angle of 50–60° with the internode; exceedingly long, slightly curving downward proximally and upward distally, tapering gradually, though rather imperceptibly, towards aperture; adaxial wall ¼ to 1/5 adnate to internode; free part with 7–9 prominent grooves; abaxial wall slightly sigmoid; basal foramen wide; distal end of hydrotheca slightly upturned; margin with four short, triangular cusps separated by shallow embayments; aperture quadrate in frontal view; an intrathecal cusp abaxially. Gonothecae absent.

Remarks

A careful search of the relevant literature reveals no other Sertularella species which approaches the present hydroid in the morphology of its hydrothecae.

Geographical distribution

New Caledonia.