Cellaria levigata, Martino & Rosso & Taylor & Chiu & Fujita & Kitamura & Yasuhara, 2025

Cellaria levigata sp. nov.

Di Martino, Rosso and Taylor

Figure 17 View FIGURE 17

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Type material. Holotype PMC. B50. 29.7.2024 a, sample 19200 ( Figure 17A–C View FIGURE 17 ); paratype PMC. B50. 29.7.2024 b1, sample 19227 ( Figure 17D–F View FIGURE 17 ); paratype PMC. B50. 29.7.2024 b2, sample 19230 ( Figure 17G–J View FIGURE 17 ); Core 19, Daidokutsu cave, Okinawa, Japan, Holocene.

Etymology. Latin, meaning smooth, referring to the smooth appearance of the cryptocyst.

Diagnosis. Cellaria with hexagonal to rhomboidal zooids arranged in whorls of 3–4; cryptocyst smooth, with thick raised ridges flanking the orifice; orifice transversely crescent-shaped with two rounded triangular denticles; vicarious avicularia elongate pear-shaped with condyles associated with fertile autozooids; fertile autozooids clustered in whorls locally inflating internode diameter; ovicell endotoichal, appearing as a fissure with lateral indentations, protected by the raised cryptocystal distal margin of the maternal zooid.

Description. Colony erect, jointed, flexible; internodes cylindrical, narrow (230–350 µm wide), tapering slightly near the node (190–200 µm), rectilinear to slightly curved, becoming inflated near clusters of fertile zooids. Autozooids distinct, separated by thin furrows between raised margins, hexagonal with parallel lateral sides and acute to rounded triangular distal and proximal margins, longer than wide (mean ZL/ZW 1.55), arranged in whorls of 3–4. Cryptocyst smooth, slightly depressed compared to the margins, but slightly convex, with the frontal area marked by two lateral raised ridges flanking the opesia, sometimes closing proximally in a V-shape or remaining open like two brackets, 12–22 µm thick. Opesia outlined by a thin (c. 10 µm) raised rim, transversely crescent-shaped with a markedly convex proximal margin, placed at the distal third of zooidal length; two rounded triangular denticles, 13–14 µm long by 16 µm wide at the base, present on the proximal margin, positioned at a certain distance from the proximal corners. Vicarious avicularia rare, pear-shaped (215 µm long by 100 µm wide), placed on larger triangular cystid, with a raised, rounded acicular rostrum, directed slightly distolaterally; two small pointed condyles directed downwards. Fertile zooids clustered in whorls causing inflation of internode width, rhomboidal with a straight to slightly convex distal margin, wider and squatter (mean ZL/ZW 1.10) and with a slightly broader opesia than autozooids. Ovicells endotoichal, appearing as a fissure 70–90 µm long by 12–24 µm wide, with two small U-shaped indentations ( Figure 17D View FIGURE 17 , arrowed), c. 20 µm deep, at the corners, covered by a visor-like rectangular portion of the distal rim of the maternal autozooid.

Measurements (µm). ZL 334±37, 280–396 (4, 14); ZW 216±39, 153–278 (4, 14); OpL 54±6, 46–69 (4, 16); OpW 92±10, 78–109 (4, 16); ZL (fertile) 318±45, 276–363 (3, 4); ZW (fertile) 287±65, 232– 372 (3, 4); OpL (fertile) 57±9, 48–67 (3, 4); OpW (fertile) 111±19, 93–128 (3, 4); AvL (cystid) 309 (1, 1); AvW (cystid) 189 (1, 1).

Remarks. Cellaria levigata sp. nov. is distinct from all Recent Japanese, North-Pacific and Indo-Pacific species of Cellaria . Cellaria anceps Harmer, 1926 differs by having internodes with six zooids in a whorl, a granular cryptocyst, and the absence of frontal ridges; Cellaria boninensis Silén, 1938 has a granular cryptocyst, more centrally placed opesia, and an avicularium with a slightly curved and asymmetrical rostrum (Di Martino, 2023); Cellaria granulata Canu and Bassler, 1929 is similar to the new species in having inflated internodes where there are fertile zooids, and fertile zooids with a convex transverse opening, but differs by having an ovicell fissure covered by a cryptocystal lamella raising from the distal zooid, and a granular cryptocyst; Cellaria japonica Canu and Bassler, 1929 shares a smooth cryptocyst with the new species but differs by having internodes larger in diameter, more than four zooids in a whorl, maternal zooids with an orbicular pore, non-inflated fertile internodes, and more centrally placed opesia; Cellaria mandibulata Hincks, 1882 , also has a smooth cryptocyst but is distinguished by its avicularia, which are shorter and twice as wide as the autozooids; Cellaria punctata (Busk, 1852) has a granular cryptocyst, more centrally placed opesia, and an avicularium with triangular squat rostrum ( Tilbrook et al., 2001); Cellaria tenuirostris (Busk, 1852) , in addition to a granular cryptocyst, also has a narrower and more pointed avicularian rostrum (Gordon, 1984; Achilleos et al., 2020; Bock, 2024).