Tricellaria inopinata d’Hondt and

Chae, Hyun Sook, Yang, Ho Jin, Min, Bum Sik, Noh, Geon Woo & Seo, Dong Hee Lee and Ji Eun, 2022, Three newly recorded species of Korean fouling bryozoans, Journal of Species Research 11 (3), pp. 180-187 : 184-185

3. Tricellaria inopinata d’Hondt and

Occhipinti Ambrogi, 1985 ( Fig. 3 )

Tricellaria inopinata d’Hondt and Occhipinti Ambrogi, 1985: 36 ; Dyrynda et al., 2000: 2001; De Blauwe and Faasse, 2001: 103; Johnson et al., 2012: 297; De Blauwe, 2022: 162.

Tricellaria occidentalis : Seo, 2005: 365 (part).

Material examined. Korea: Gangwon-do: Gangneung , Geumjin Port, 31 October 2003 ; Gyeongsangbuk-do: Ulleungdo Island , Hyeonpo-ri, 5 May 2014 , intertidal; Jeollanam-do: Chengsan Island , Eup-ri, 13 June 2017 , port; HNIBRIV340-344, Jeollanam-do: Yeosu, Sado Island , 28 July 2021 .

Substratum. Rocks and ropes.

Description. Colony light yellow in color, erect, bushy, arborescent in form, composed of branches softly curved and rolled inward ( Fig. 3A ). Branching with joint, dichotomous. Internode consisted of 3-7 zooids (most three). Zooids biserial, alternate, elongate, vary in size, narrow proximally, 0.30-0.52 mm long (0.43± 0.08 mm) ( Fig. 3B ). Opesia oval to elliptical, 0.09-0.22 mm long (0.18± 0.04 mm), 0.05-0.12 mm wide (0.09± 0.02 mm). All zooids five to six tubular jointed spines, asymmetrically placed, located above middle of length of opesia; two to three spines turned slightly outward, located at outer distal side, robust, elongate, sometimes one spine in middle very thin compared to other spines; two to three spines at inner side, slender and generally straight compared with outer distal side spines ( Fig. 3B ). Proximal one of disto-external spines mostly divided ( Fig. 3D ). Axial zooids at bifurcations mostly six spines (sometimes five) tubular with jointed, asymmetrically placed, autozooids spines-like shapes and positions; medina spines one or two are long, prominent ( Fig. 3C ). Scutum attached to proximal to middle of inner margin of opesia, flabellate, forked into two or several irregularly lobed distally, large enough to cover most of opesia ( Fig. 3B, C ). Only lateral avicularia found, moderately large, triangular with hooked rostrum: lateral margin serrated by projecting lateral avicularia ( Fig. 3B, D ). Ovicell globular, smooth, perforated with 8 to 20 irregularly pores, longer than wide, 0.07-0.16 mm long (0.13± 0.03 mm), 0.09-0.14 mm wide (0.12± 0.02 mm) ( Fig. 3D ). Ancerstrula not observed.

Distribution. Korea, and wide distribution (http://bryozoa.net/ 6 May 2022).

Remarks. This species resembles to Tricellaria occidentalis (Trask, 1857) , which is a typical fouling bryozoan from Korea. According to Dyrynda et al. (2000), the morphology and variation of the scutum of this species are the key diagnostic features which are used to distinguish between T. inopinata and T. occidentalis . The scutum of T. inopinata is variable in shape within a single colony, flabellate, forked into 2 or several irregularly lobes, an ex- tensive structure over-arching the opesia with an irregular margin, whereas T. occidentalis has slender or slightly spatulate scutum ( d’Hondt and Occhipinti Ambrogi, 1985; Dyrynda et al., 2000; De Blauwe and Faasse, 2001; Johnson et al., 2012; De Blauwe, 2022).

Tricellaria occidentalis from Geumjin Port reported by Seo (2005) is synonymized into T. inopinata . Other specimens need to be reexamined. Tricellaria inopinata looks conspicuous with a less curved colony than T. occidentalis .

Figures

Fig. 3. Tricellaria inopinata d’Hondt and Occhipinti Ambrogi, 1985.A, Colony; B, Zooidal arrangement, spines and scutums; C, Axial zo- oids at bifurcations; D, Ovicells, divided disto-external proximal spines and lateral avicularia. Scale bars: A=10mm; B=0.3 mm; C=0.05 mm, D=0.2 mm.