Sertularia scruposa Linnaeus, 1758: 815

HAYWARD, PETER J. & McKINNEY, FRANK K., 2002, Northern Adriatic Bryozoa From The Vicinity Of Rovinj, Croatia, Bulletin of the American Museum of Natural History 2002 (270), pp. 1-139 : 27-36

Sertularia scruposa Linnaeus, 1758: 815 . Scrupocellaria scruposa: Gautier, 1962: 92 . Hay­

ward and Ryland, 1998: 276.

DESCRIPTION (AMNH 909, 914–916;

CMRR 2215): Colonies erect, branching

tufts, to 20 mm in present material; branches dividing dichotomously, each ramus supported by a bipartite, chitinous joint. Branches flat, consisting of two alternating autozooid series, opesiae of adjacent autozooids not or scarcely overlapping. Autozooids elongate, slender, commonly 0.5 X 0.2 mm, with narrowly oval opesia occupying half or less of total frontal length; opesia with a narrow border of cryptocystal calcification. Three spines present at outer distal corner of autozooid, two at inner corner, all erect, straight and slender. No scutum. Lateral avicularia variably sized, from one­third to onehalf length of opesia; rostrum perpendicular to longitudinal branch axis, projecting conspicuously, with pronounced distal hook. A small, distally directed frontal avicularium present distal to ovicell, which is globular, longer than wide, with a highly arched aperture and drop­shaped frontal fenestra. Basal vibraculum small, at outer proximal corner of autozooid; cystid parallel to longitudinal branch axis, with short setal groove only slightly oblique to it. Two vibracula present at axil between each dichotomy.

DISTRIBUTION: Scrupocellaria scruposa is common in shallow coastal waters in the entire northeast Atlantic region, from Iceland to the Cape Verde Islands, and throughout the Mediterranean.

MEASUREMENTS (SKELETAL): DO 364 ± 89 µm, 273–501 (2, 19), OpL 209 ± 29, 170– 274 (2, 16), OpW 127 ± 20, 106–191 (2, 16), OvL 168 ± 17, 151–184 (2, 4), OvW 183 ± 9, 171–193 (2, 4), ZL 491 ± 37, 428– 543 (2, 15), ZW 183 ± 20, 137–212 (2, 16).

GENUS CABEREA LAMOUROUX, 1816

Caberea boryi ( Audouin, 1826) Figure 12A–E

Crisia boryi Audouin, 1826: 242 . Savigny, 1809: pl. 12 figs 4.1–4.6.

Caberea boryi: Gautier, 1962: 93 . Prenant and Bobin, 1966: 449. Hayward and Ryland, 1998: 252.

DESCRIPTION (AMNH 917–919; CMRR 2216): Colonies stiff, erect fans, to 8 mm high in present material, with cylindrical branches dividing dichotomously at regular intervals; without visible joints at the dichotomies. Autozooids in two alternating longitudinal series, or three just prior to dichotomies, defining the frontal surface of the branch, commonly 0.35 X 0.2 mm. Frontal planes of the two autozooid series angled at about 90° to each other; longitudinal axis of each autozooid slightly oblique to branch axis, inclining medially. Frontal surfaces of alternate autozooids slightly overlapped; opesia and operculum together constituting four­fifths of total frontal length, bordered proximally and laterally by broad, finely granular cryptocyst, no frontal gymnocystal calcification present. Three distal oral spines present: two on inner distal angle of autozooid and one, very much longer, on the out­ er distal angle. Much of opesia obscured by thick, oval scutum, attached by a thick stalk just proximal to inner distal spines; its distal edge straight, abutting with a blunt process projecting from opposite, outer edge of the opesia, and defining the proximal border of the operculum, which is terminal in position and tilted basally at a marked angle to frontal plane. A small adventitious avicularium on the inner distal angle of many autozooids, with short triangular mandible, distally directed; frequently, a much larger avicularium proximal to dichotomy, with broadly triangular rostrum frontally directed and almost perpendicular to frontal plane. Ovicell recumbent on distally succeeding autozooid, inclined medially; broader than long, with highly arched aperture bordered by broad band of uncalcified ectooecium. Abfrontal surface of colony distinctive: basal wall of each autozooid obscured by a large, proximally tapered vibraculum; seta 1.5 mm long, finely toothed along one edge, fitting into a narrow groove extending from outer distal edge of vibraculum, proximally and medially, contributing to a pronounced ridge extending length of branch. Thin kenozooidal rhizoids arising from vibracular chambers, passing proximally along median abfrontal surface of each branch and coalescing as thick bundles at base of colony.

Tentacles clear, 13; lophophores campylonemidan.

DISTRIBUTION: Caberea boryi is widespread and abundant in shallow inshore waters throughout the Mediterranean, and ranges northwards to the southwest British Isles, and southwards to South Africa. It has been

recorded from the Red Sea and the Indian Ocean, and from the West Pacific.

MEASUREMENTS (SKELETAL): DO 223 ± 34 µm, 172–310 (3, 28), OvL 122 ± 9, 110– 137 (1, 6), OvW 156 ± 14, 142–181 (1, 6), ZL 357 ± 40, 265–435 (3, 29), ZW 147 ± 11, 132–169 (1, 9). (POLYPIDE): IH 32 ± 7 µm, 20–40 (1, 9), LDMn 438 ± 27, 400– 460 (1, 6), LDMx 497 ± 37, 440–540 (1, 9), MD 20 ± 0 (1, 5), TL 443 ± 55, 360–540 (1, 10).

SUPERFAMILY MICROPOROIDEA GRAY, 1846 FAMILY MICROPORIDAE GRAY, 1848 GENUS CALPENSIA JULLIEN, 1888

Calpensia nobilis (Esper, 1796)

Figure 13A–C

Cellepora nobilis Esper, 1796: 145 .

Membranipora bifoveolata Heller, 1867: 95 .

Calpensia nobilis: Gautier, 1962: 59 . Zabala,

1986: 289. Zabala and Maluquer, 1988: 90.

Hayward and Ryland, 1998: 292.

DESCRIPTION (AMNH 981, 1008; CMRR 2217): Colonies widely spreading, multiserial, flat, light­colored grayish­brown sheets, often exceeding 10 X 10 cm; through successive phases of regeneration and overgrowth may form thick cylinders and nodules on every kind of hard substratum. Autozooids simple rectangles or hexagons with a thick, densely perforated cryptocyst, a small terminal opesia, equivalent to about 12% total autozooid length and coincident with the operculum, and paired opesiules almost as large as opesia. Outer epitheca glistens in dried material. First asexual zooid budded from distal end of ancestrula but with growth direction oriented 120° with respect to ancestrula and lying beside ancestrula, establishing early colony growth in direction opposite the polarity of the ancestrula (fig. 13C). Occasional reparative autozooidal budding. No polymorphs.

Cystids are occupied by a succession of up to four generations of polypides, and the brown body remains of previous polypides are stored in the proximal portions of zooids. Proximal portions of large colonies are senescent and commonly are bright green in color due to a thin growth of chlorophyte algae.

Tentacles clear, 19–22; lophophores bell­ shaped, radially symmetrical, supported on very long introverts, commonly overlapped with adjacent lophophores up to 300 µm.

REMARKS: This common and conspicuous Mediterranean species is sufficiently distinctive to be recognized with the unaided eye. Poluzzi and Coppa (1991) described growth and regeneration in C. nobilis , in relation to spatial competition. McKinney and Jaklin (1993) reported ephemeral populations of free­lying colonies composed of single zooid­thick sheets, up to several centimeters in diameter, off the Istrian Peninsula 30 to 50 km south­southwest of Pula. Ristedt (1991) described the ancestrula and early astogeny, but sexual reproduction has not been described.

OCCURRENCE: This species encrusts virtually every type of nontoxic firm to hard substratum, including rock, shell debris, pottery, glass, other bryozoans, thecate ascidians, and—elsewhere in the Adriatic and Mediterranean ( Poluzzi and Coppa, 1991)—marine grasses.

DISTRIBUTION: The species is widespread throughout the Mediterranean and occurs sparsely northwards to the Gulf of St. Malo, and on the northwest African coast.

MEASUREMENTS (SKELETAL): DO 530 ± 93 µm, 366–684 (2, 20), OpL 96 ± 8, 80–107 (2, 20), OpW 150 ± 17, 119–174 (2, 20), ZL 817 ± 70, 719–935 (2, 20), ZW 383 ± 36, 322–439 (2, 20). (POLYPIDE): IH 495 ± 283 µm, 220–1200 (4, 21), LD 955 ± 128, 480–1140 (4, 40), MD 34 ± 8, 20–50 (3, 9), TL 654 ± 63, 560–820 (4, 18).

GENUS ROSSELIANA JULLIEN, 1888

Rosseliana rosselii ( Audouin, 1826) Figure 14A–E

Flustra rosselii Audouin, 1826: 240 .

Membranipora rosselii: Hincks, 1880: 166 .

Rosseliana rosselii: Canu and Bassler, 1925: 17 . Hayward and Ryland, 1998: 294.

Rosseliana ‘‘sp. nov.’’ Gautier, 1962: 63.

DESCRIPTION (AMNH 1053–1055; CMRR 2218): Colonies multiserial encrusting, flat, beige colored. Autozooids arched oval distally and tapered proximally (proximal shape determined by shape of immediately preceding zooids), with boundaries marked by prominently raised lateral walls around arched distal end. Gymnocyst absent; cryptocyst flat to gently arched transversely, with coarse­grained or finely tuberculate surface. Opesia terminal, semielliptical with very slightly concave proximal edge, equivalent to about 40% total autozooid length. Ancestrula similar to autozooids; first three asexually budded zooids distal and distolateral; primary astogenetic zone of change only three or four generations Ovicell small, largely immersed, apparent as shallow crescentic cap at distal end of zooid.

Tentacles clear, 15; lophophores bellshaped, radially symmetrical away from colony margin between chimneys, obliquely truncate adjacent to chimneys and colony margin; introverts long.

REMARKS: Gautier (1962: 63–64) used R. rosselii for Rosseliana with large zooids (length 0.70–0.82 mm) and distinguished an unnamed new species for colonies with smaller zooids (length 0.40–0.68 mm). We encountered only colonies with the smaller zooids, essentially equivalent in size to the zooids of colonies attributed to R. rosselii around Britain ( Hayward and Ryland, 1998: 294). Prenant and Bobin (1966: 346–348) noted the two forms recognized by Gautier but indicated that they seem to co­occur ecologically and geographically and could not at the time be separated into two distinct species. Although only one of the forms has been found by us in the northern Adriatic, suggesting that the geographic ranges of the two ‘‘forms’’ or perhaps species are not fully coincident, we have preferred to retain the name R. rosselii for the northern Adriatic specimens.

DISTRIBUTION: This species is widespread in the eastern temperate Atlantic, from the Cape Verde Islands to Shetland, and throughout the Mediterranean.

MEASUREMENTS (SKELETAL): DO 452 ± 46 µm, 363–520 (2, 20), OpL 246 ± 24, 218– 308 (2, 20), OpW 227 ± 27, 185–277 (2, 20), ZL 591 ± 30, 533–668 (2, 20), ZW 375 ± 45, 307–457 (2, 20). (POLYPIDE): IH 366 ± 127 µm, 200–720 (2, 22), LDMn 560 ± 62, 400–630 (2, 13), LDMx 622 ± 72, 420– 840 (2, 24), MD 24 ± 3, 20–30 (2, 10), TLMn 476 ± 62, 340–590 (2, 23), TLMx 588 ± 113, 400–790 (2, 25).

GENUS MOLLIA LAMOUROUX, 1816

Mollia circumcincta ( Heller, 1867)

Figure 13D–H

Membranipora circumcincta Heller, 1867: 96 .

Mollia circumcincta: Gautier, 1962: 61 . Zabala

and Maluquer, 1988: 92.

NEOTYPE (chosen here): UIIZ 116.

DESCRIPTION (AMNH 920, 921; CMRR 2219): Colonies light orange, encrusting, multiserial, unilaminar sheets. Autozooids oval, 0.375–0. 50 mm; disjunct, each linked to its neighbors by about 12 short, tubular communication organs. Frontal body wall membranous, underlain for about two­thirds of its extent by a vitreous, granular cryptocyst; opesia semielliptical, the proximal edge straight or slightly convex, and gently arched frontally, with indistinct opesiular indentations at each corner. Vertical walls of the autozooid develop a crenulate mural rim, which is especially raised distally, forming a cowl above the distal edge of the opesia. Spines absent, except in first two or three astogenetic generations. Ovicell hemispherical, partially immersed, with a crenulate vertical wall bordering a vitreous, nodular cryptocystal frontal surface. No polymorphs other than kenozooids, which may occur in clusters.

Tentacles clear, 15; lophophores bellshaped, radially symmetrical away from colony margin between chimneys, obliquely truncate adjacent to chimneys and colony margin; introverts long.

REMARKS: Specimens of Mollia circumcincta collected from the Rovinj area are conspecific with bryozoan specimen 116 in the University of Innsbruck Institute of Zo­ ology, labeled as ‘‘ Caleschara patellaria var. circumcincta Heller. Adria (S. Heller) 9837.’’ There is no annotation that this specimen is one of Heller’s original types, but we illustrate it here as at least an indication of long consistency in concept of the species and designate it as neotype for the species. If eventually discovered to be a specimen on which Heller originally described Membranipora circumcincta , it should be redesignated as lectotype.

DISTRIBUTION: This pretty species was first described from the Adriatic ( Heller, 1867) and has been reported from very few additional localities. It is known from the Siculo­ Tunisian shelf and the northwest Mediterranean ( Gautier, 1962), but does not seem to range outside of the Mediterranean.

MEASUREMENTS (SKELETAL): DO 336 ± 36 µm, 264–412 (2, 20), OpL 86 ± 14, 62–107 (2, 20), OpW 120 ± 19, 84–159 (2, 20), OvL 102 ± 10, 82–115 (2, 17), OvW 174 ± 12, 156–206 (2, 17), ZL 410 ± 35, 371–479 (2, 20), ZW 267 ± 24, 234–338 (2, 20).

SUPERFAMILY CELLARIOIDEA FLEMING, 1828 FAMILY CELLARIIDAE FLEMING, 1828 GENUS CELLARIA ELLIS AND SOLANDER, 1786

Cellaria fistulosa ( Linnaeus, 1758) Figure 15A–E

Eschara fistulosa Linnaeus, 1758: 804 .

Cellaria fistulosa: Hayward and Ryland, 1998: 306 .

DESCRIPTION (AMNH 922; CMRR 2220): Colonies erect, branching, consisting of rigid, cylindrical internodes formed from alternating whorls of three to six autozooids, linked by flexible, chitinous nodes at which dichotomous branching occurs. Internodes 2–9 mm long, typically about 5 mm, in present material, with diameter 0.45–0.7 mm, typically about 0.55 mm. Colonies attach by bundles of tubular rhizoids developed from the frontal cuticles of the proximal autozooids of the colony. Autozooids diamondshaped or hexagonal in outline; successive autozooids of longitudinal rows commonly but not always in contact along common transversely linear border and completely bounded laterally by the two adjacent offset rows of autozooids; less commonly succes­ sive zooids in longitudinal rows separated by line marking contact between the two adjacent offset rows of autozooids. Frontal membrane distinct and glistening in living material; in cleaned specimens, cryptocystal frontal shield concave between prominent ridges marking boundaries of autozooids. Calcification finely nodular; opesia wider than long, equivalent to one­sixth zooid length, distal rim arched and finely beaded, proximal rim convex, with a blunt, frontally curved denticle in each proximal corner. A pair of wellmarked longitudinal cryptocystal ridges apparent on each side of the opesia, extending proximal to it, converging but not meeting. Avicularia about one­third length of autozooids, rounded­quadrangular, with a narrow, semielliptical opesia; mandible narrowly crescentic, supported on an arched rostrum, directed distally or distolaterally. Ovicell aperture small and rounded, situated immediately distal to opesia, partially occluded in older parts of colonies by calcified plate extending from proximal edge, as has been not­ ed elsewhere for C. salicornioides ( Hayward and Ryland, 1998) .

Tentacles clear, 13; lophophores bellshaped, radially symmetrical.

DISTRIBUTION: Common in shallow, coastal waters throughout the Mediterranean, and northwards to the British Isles, western Norway and Iceland.

MEASUREMENTS (SKELETAL): DO 314 ± 23 µm, 252–345 (2, 16), OpL 71 ± 8, 60–87 (2, 20), OpW 107 ± 8, 97–126 (2, 17), ZL 564 ± 21, 510–601 (2, 20), ZW 262 ± 14, 241–283 (2, 15). (POLYPIDE): IH 67 ± 27 µm, 20–100 (1, 6), LD 534 ± 38, 490–580 (1, 7) MD 30 (1, 1), TL 437 ± 29, 400–480 (1, 6).

Cellaria salicornioides Lamouroux, 1816 Figure 15F–K

Figures

Fig. 12. A–E. Caberea boryi. A. Frontal surface of untreated branches (AMNH 917; 0.5 mm). B. Serrated vibracular setae (AMNH 917; 0.1 mm). C. Ancestrula (AMNH 918; 0.1 mm). D. Reverse surface of treated branch with conspicuous proximally tapered vibraculae (AMNH 919; 0.1 mm). E. Frontal surface of branch, with autozooid (right) and (left) maternal zooid with ovicell and distal avicularium (AMNH 917; 0.1 mm).

Fig. 13. A–C. Calpensia nobilis. A. General aspect (AMNH 981; 0.5 mm). B. Autozooid (AMNH 981; 0.1 mm). C. Ancestrula and early autozooids (AMNH 1008; 0.2 mm). D–H. Mollia circumcincta. D. General aspect (AMNH 920; 0.5 mm). E. Lectotype, untreated, with several kenozooids at colony margin (upper right; UIIZ 116; 0.5 mm). F. Lectotype, autozooid (UIIZ 116; 0.1 mm). G. Maternal zooid with ovicell, flanked by autozooids (AMNH 920; 0.1 mm). H. Ancestrula and early autozooids (AMNH 921; 0.1 mm).

Fig. 14. A–E. Rosseliana rosselii. A. General aspect (AMNH 1053; 0.5 mm). B. Autozooid (AMNH 1053; 0.1 mm). C. Maternal zooid with largely immersed ovicell (AMNH 1054; 0.1 mm). D. Growing edge of colony (AMNH 1055; 0.10 mm). E. Ancestrula and early autozooids (AMNH 1055; 0.2 mm).

Fig. 15. A–E. Cellaria fistulosa (AMNH 922). A. Typical surface of young branch, distal joints not yet decalcified (0.5 mm). B. Branch with swollen area of maternal zooids (bottom of figure) and (top left) only one distal joint decalcified (0.5 mm). C. Branch segment with several distal autozooids with proximal perforations from which non­calcified rhizooidal kenozooids emerged (0.5 mm). D. Autozooids (bottom of figure) with proximal perforations for kenozooids, small avicularium (center), and maternal zooids with brood chambers (top of figure; 0.1 mm). E. Avicularium separating two maternal zooids with calcified plates restricting brood chamber apertures (0.1 mm). F–K. Cellaria salicornioides. F. Typical surface of young branch, distal joints not yet decalcified (AMNH 923; 0.5 mm). G. Autozooids, one with proximal perforation for kenozooid (AMNH 923; 0.1 mm). H. Base of laterally budded branch (AMNH 923; 0.2 mm). I. Avicularium (AMNH 924; 0.1 mm). J. Polymorphic zooid from which lateral