Cryptosula Canu and Bassler, 1925

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 : 3749-3752

Genus Cryptosula Canu and Bassler, 1925

Cryptosula zavjalovensis Kubanin, 1976

( Figure 18A, B )

Cryptosula zavjalovensis Kubanin 1976, p 33 , Figure 1G, H .

Cryptosula zavjalovensis: Grischenko 2004, p 40 . Lepralia reticulata Okada 1929, p 24 , Plate 5, Figures 4 , 5 ; not Lepralia reticulata

MacGillivray, 1842.

Lepralia reticulata: Androsova 1958, p 129 , Figure 46.

Lepralia pallasiana: O’Donoghue 1925, p 19 , Plate 2, Figure 6 .

Cryptosula pallasiana: Dick and Ross 1986, p 89 .

Cryptosula okadai Dick and Ross 1988, p 53 , Plate 5F.

Cryptosula okadai: Grischenko 1997, p 176 .

Description

Colony. Unilaminar, encrusting, sheet-like, brownish orange in colour at Ketchikan; with a sharp, pungent odour when alive or newly dried.

Zooids. Rectangular, barrel-shaped, or roughly hexagonal; distinct, outlined by a shallow groove and a suture line formed by adjacent vertical walls. Two sizes occur in different astogenetic zones, longer zooids 0.70–1.13 mm long (average 50.833 mm, n 510, 1) by 0.30–0.58 mm wide (average 50.404 mm, n 510, 1) with a broad orifice ( Figure 18A ), and shorter zooids 0.58–0.68 mm long (average 50.628 mm, n 510, 1) by 0.30–0.45 mm wide (average 50.400 mm, n 510, 1) with a narrow orifice ( Figure 18B ).

Frontal wall. Slightly to quite convex, perforated with large circular pores evenly spaced over the entire surface, but not extending distally around orifice; rising to a slight to tall, blunt, conical umbo proximal to orifice. Frontal wall thickens with age, the pores becoming infundibular and the surface between them granular.

Orifice. Hat-shaped in outline, with a large, semicircular anter constricted from a short, broad poster by long, low condyles; two sizes, the broader type 0.18–0.20 mm long (average 50.184 mm, n 510, 1) by 0.20–0.23 mm wide (average 50.215 mm, n 510, 1), the narrower type 0.16–0.19 mm long (average 50.178 mm, n 510, 1) by 0.16–0.20 mm wide (average 50.181 mm, n 510, 1).

Spines and avicularia. Lacking.

Ovicells. Lacking; embryos brooded internally.

Ancestrula . Tatiform, without spines ( Dick and Ross 1988), but not observed at Ketchikan.

Remarks

This species was recorded only at Higgins Point, where we found one damaged colony 2 cm across on a boulder. In the Ketchikan specimen, two astogenetic zones are evident: a central area of larger zooids and a marginal area of smaller zooids. Three types of astogenetic zone have been reported for this species. Both Okada (1929) and Dick and Ross (1988) noted in some colonies a marginal zone of autozooids lacking an orifice. Kubanin (1976) noted zones of larger and smaller zooids, but the differences in zooid and orifice size were less pronounced than in the Ketchikan specimen.

Cryptosula zavjalovensis differs from its similar but more southern congener C. pallasiana ( Moll, 1803) in having a straight rather than a curved proximal margin of the orifice; in lacking pores around the distal curvature of the orifice; and in having zones of marginal zooids without orifices, though such zooids are by no means evident in all colonies of C. zavjalovensis and occasionally occur in C. pallasiana . In addition, zooids of C. pallasiana occasionally have a small, median suboral avicularium ( Osburn, 1952), which has not been observed in C. zavjalovensis . Finally, a diagnostic character of C. zavjalovensis is the intense, pungent odour it exudes. We have noted this odour in live material from Ketchikan, Kodiak, and Dutch Harbour in Alaska; the Commander Islands; and Akkeshi, Hokkaido, Japan. The odour is retained for some time in dried specimens, but gradually fades. No similar odour has been reported for C. pallasiana ; however, neither had it been reported for C. zavjalovensis until noted by Dick and Ross (1988).

Okada (1929) first described this species as Lepralia reticulata , which proved to be a junior synonym of Lepralia reticulata MacGillivray, 1842 . Dick and Ross (1988) renamed the species Cryptosula okadai , unaware that Kubanin (1976) had described the same species as C. zavjalovensis . Kubanin’s name takes priority over C. okadai in replacing L. reticulata Okada.

Distribution

Extending from the mid-intertidal zone to a depth of at least 40 m ( Androsova 1958), C. zavjalovensis is one of the most common and widespread bryozoans found intertidally around the north Pacific rim. On the North American side, records exist from Ketchikan (present study), northern Gulf of Alaska, Kodiak Island, eastern Aleutian Islands, and Bering Sea ( O’Donoghue 1925; Dick and Ross 1988). On the Asian side, there are records from the Gulf of Anadyr, Commander Islands, Kamchatka, Sea of Okhotsk, and northern mainland of the Sea of Japan ( Grischenko 1997, 2004; Kubanin 1997); in Japan, it is patchily abundant at Akkeshi, Hokkaido (our observations) and occurs at Mutsu Bay, northern Honshu ( Okada 1929).

Figures

Figure 1. Membranipora villosa Hincks. (A) ‘‘Membranacea’’ form, weakly bleached; (B) ‘‘serrilamella’’ form, bleached; (C) ‘‘villosa’’ form; unbleached; note acute chitinous spines at proximal corners and cuticular spines on frontal membranes; (D) ‘‘villosa’’ form; same colony as (C) after bleaching, showing weakly denticulate cryptocyst; (E) ‘‘villosa’’ form from Sitka, Alaska; weakly bleached specimen with zooids showing both denticulate cryptocyst and cuticular spines on frontal membrane; (F) ‘‘villosa’’ form from Sitka, Alaska; same colony as (E), with zooids showing coarse, highly denticulate cryptocyst. Scale bars: 500 Mm (A–C, E, F); 400 Mm (D).

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).

Figure 18. (A, B) Cryptosula zavjalovensis Kubanin: (A) group of autozooids with broad-type orifice; (B) group of autozooids, with broader and narrower orifices. (C, D) Microporella setiformis O’Donoghue and O’Donoghue: (C) group of autozooids; (D) enlargement of orifice, ascopore, and marginal avicularium. All specimens bleached. Scale bars: 500 Mm (A–C); 200 Mm (D).