Bathykorus bouilloni Raskoff, 2010, sp. nov.

• Main Author: Raskoff, Kevin A.
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2010
• Subjects: Biodiversity; Taxonomy; Animalia; Cnidaria; Hydrozoa; Narcomedusae; Aeginidae; Bathykorus; Bathykorus bouilloni; Arctic
• Online Access: https://doi.org/10.5281/zenodo.6196508; http://treatment.plazi.org/id/3D24C725E73CFFF5FF06F895FE73F916

Bathykorus bouilloni sp. nov. Bell. The medusae shows primarily tetramerous symmetry with the umbrella being dome-shaped and the apex having a pronounced thickening of the mesoglea; with a maximum observed diameter of 1.5cm and height of 1.1cm (Figure 1). The mesoglea becomes thinner at the margins and has a uniform light blue coloration in life which turns milky-white when preserved. The bell is incised or lobed below the origin of the primary tentacles forming the peronia (Figure 1 D). There is a thin velum on the inside edge of the umbrellar margin. Tentacles. There are four primary, solid, noncontractile tentacles which originate above the umbrellar margin and peronia (one specimen of 25 collected was found with five tentacles) that are two to three times as long as the medusa is wide. These primary tentacles have deep endodermal tentacular roots that anchor into the mesoglea through the exumbrellar surface (Figure 1 E). On the margin of the bell there is one secondary tentacle per quadrant hanging free from the edge of the lappet (one specimen was found with two secondary tentacles in a single quadrant) (Figure 1 C&D). The core of the tentacles is made of very large vacuolated endodermal chordal cells (Figure 2 A&B). Subumbrella. The mouth is simple and circular, but can fold into irregular patterns with muscular movement. The mouth extends into a wide and flat gastric cavity that leads into the interradial manubrial pouches, a feature characteristic of the Aeginidae. There are typically three manubrial pouches per primary tentacle (Figure 1 D), although one specimen was observed with four pouches in one of its quadrants. There are an equal number of simple canals to the tentacles (usually four) which quickly bifurcate into the peripheral and peronial canals which follow along the margin of each interradial lappet. It was not determined if the canals are hollow, or solid as is common for some narcomedusae. Statocysts. There are typically two free hanging, ecto-endodermic statocysts found in each ...