Cirriformia abyssalis, Jimi & Fujiwara & Kajihara, 2024

Cirriformia abyssalis sp. nov.

[New Japanese name: Hukaba-mizuhiki] ( Figs 22–24 View Fig )

Material examined. Tateyama: one of unknown sex, body length 102 mm, body width 3 mm, 308 chaetigers, 12 December 2014, coll. Otyanomizu University Marine Coastal Research Center, Toshiaki Shitamitsu, Hayate Tanaka, Naoto Jimi. Holotype (NSMT-Pol H-952), COI INSD accession no. PP891595.

Description. Body length 102 mm and width 3 mm, 308 chaetigers, and color in life orange. Color in alcohol pale yellow ( Fig. 22A View Fig ). Specimen with black pigmentation in anterior ventral zone. Body elongated, soft, dorsally inflated and grooved throughout, a wide, deep groove present long entire body. Eyes absent. Prostomium broad triangular ( Fig. 23). Paired nuchal organs located on prostomium. Peristomium with one annulation and some wrinkles, deeply grooved in junction between peristomium and chaetiger 1. Branchiae start from chaetiger 1, one pair per segment. Branchiae arising from notopodial ridge, in posterior segments, inserted at discrete distance from notopodial ridge, not shifting in mid-dorsal section. Notopodia and neuropodia separated, forming shoulders shifting from a position closer to dorsum to a more median position along midbody. Two groups of dorsal tentacles arising from chaetigers 7–8; each group with 22–30 tentacles. Dorsal tentacles organized in two groups each. Notopodia and neuropodia with capillary chaetae and spines. Notochaeta: 3–15 capillary chaetae per fascicle along entire body, 2–5 spines ( Fig. 24A View Fig ) present from chaetiger 61 and following chaetigers, spines short, slightly curved, blunt, blade shape. Neurochaeta: 2–16 capillary chaetae per fascicle along entire body, 3–5 spines ( Fig. 24B View Fig ) present from chaetiger 43 and following chaetigers, spines short, slightly curved, blunt, blade shape. Pygidium simple, with terminal anus.

Methyl Green Staining Pattern. The edge of dorsal area of chaetigers 2–6 was notably stained. Segment after tentacles were stained forming complete rings around segments, inter-segmental grooves not staining ( Fig. 22B, C View Fig ).

Etymology. The specific name is an adjective after the habitat of the type specimen (muddy bottom of continental shelf). The specific name is an adjective.

Distribution and habitat. Only known from muddy bottom of continental shelf, Tokyo Bay (53–74 m).

Remarks. See remarks of C. akiyoae .