BUGULIDAE Gray, 1848

Dick, Matthew H., Grischenko, Andrei V. & Mawatari, Shunsuke F., 2005, Intertidal Bryozoa (Cheilostomata) of Ketchikan, Alaska, Journal of Natural History 39 (43), pp. 3687-3784 : 3712-3714

Family BUGULIDAE Gray, 1848

Genus Bugula Oken, 1815 Bugula pacifica Robertson, 1905

( Figure 6A, B )

Bugula pacifica Robertson 1905, p 268 , Plate 10, Figure 50, Plate 16, Figure 101.

Bugula purpurotincta: Robertson 1900, p 320 , Plate 20, Figures 5 , 6 .

Bugula pacifica: O’Donoghue and O’Donoghue 1923, p 20 ; 1925, p 100; 1926, p 45; Osburn 1950, p 155, Plate 22, Figure 6 , Plate 23, Figure 4 ; Soule et al. 1995, p 108, Plate 36.

Description

Colony. Erect, branched, flexible; attached by a stalk composed of rhizoids originating from zooids at base of colony; branches biserial ( Figure 6A ), dichotomously branching, spiralled around a central axis with the frontal sides facing inwards. Branching pattern Type 3 ( Harmer 1923; Hayward and Ryland 1998), with axil at bifurcations formed by inner pair of two pairs of zooids flanking branch point. The colonies we collected were young, the largest 1 cm high.

Zooids. Elongate, 0.45–0.90 mm long (average 50.646 mm, n 515, 3) by 0.13–0.20 mm wide (average 50.154 mm, n 515, 3), tapering proximally and truncate distally; walls thin,

weakly calcified, flexible, translucent. Opesia occupies nearly entire exposed frontal area, leaving only a small zone of proximal gymnocyst.

Spines ( Figure 6B ). In our material, two short, spinous projections on outer distal zooidal margin; no spine on inner distal margin.

Avicularia ( Figure 6B ). Attached by a flexible joint near base of zooid, on lateral wall close to opesial margin; approximately twice as long as deep, 0.16–0.24 mm long

(average 50.215 mm, n 510, 1) by 0.08–0.11 mm deep (average 50.101 mm, n 510, 1); hooked at end; not occurring on all zooids.

Ovicell. Not observed in our specimens, but in this species a reduced, hood-like ooecium occurs.

Remarks

We found this species only at the East Tongass Narrows site, where it was uncommon in rock crevices.

Distribution

Bugula pacifica is distributed from the Pribilof Islands, Bering Sea ( Robertson 1905; Osburn 1950) southward to the Channel Islands off Southern California ( Soule et al. 1995). On the Asian side, it has been reported from the Commander Islands ( Grischenko 1997, 2004).

Figures

Figure 4. (A–D) Cauloramphus tortilis n. sp.: (A) autozooids; unbleached; (B) autozooids, bleached; complete zooid at right is a brooding zooid, with a crescentic kenozooidal ooecium around distal margin; (C) young autozooids near colony margin, showing intermeshing spine bases; bleached; (D) colony margin, showing pore chambers; bleached. (E, F) Tegella aquilirostris (O’Donoghue and O’Donoghue): (E) ovicellate zooids; unbleached; (F) ovicellate zooids; bleached. Scale bars: 500 Mm.

Figure 5. (A–D) Tegella horrida (Hincks): (A) group of ovicellate zooids near colony margin, well separated with scattered lacunae between them; bleached; (B) group of heavily calcified ovicellate zooids, the avicularium proximal to opesia completely immersed; bleached; (C) group of ovicellate zooids; unbleached; (D) autozooid (left) and intramural reparative avicularium (right); bleached. (E, F) Hincksina longiavicularia Gontar: (E) group of autozooids and spatulate vicarious avicularia; unbleached; (F) several ovicellate zooids; unbleached. Scale bars: 500 Mm (A–C, E); 200 Mm (D, F).

Figure 6. (A, B) Bugula pacifica Robertson: (A) general colony view; (B) autozooids and lateral avicularia. (C, D) Bugula pugeti Robertson: (C) general colony view; (D) autozooids and lateral avicularia; note smaller avicularium near branch point (near top, right of centre). (E, F) Dendrobeania lichenoides Robertson: (E) autozooids and one ovicellate zooid; (F) abfrontal surface of portion of colony, showing attachment radicles. All specimens unbleached. Scale bars: 2 mm (A, C); 400 Mm (B); 1 mm (D, F); 500 Mm (E).