Tubulipora deflexa Couch, 1844: 107

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 : 110-112

Tubulipora deflexa Couch, 1844: 107 . Pustulipora deflexa: Johnston, 1847: 279 . Pustolopora deflexa: Heller, 1867: 125 . Entalophoroecia deflexa: Harmelin, 1976: 108 .

Hayward and Ryland, 1985a: 113. Zabala,

1986: 630. Zabala and Maluquer, 1988: 168. Entalophora gallica d’Orbigny, 1853: 781 .

DESCRIPTION (AMNH 1027, 1028; CMRR 2275): Colonies light golden­brown, encrusting multiserial runners to erect, with bifurcating, radially symmetrical branches. Branch surfaces typically finely corrugated, zooidal boundaries not clear. Autozooidal peristomes bent at acute angles relative to the distal growth direction of the branches; distances between points of origin, and distances between outer ends, of peristomes highly variable.

Brood chambers only at branch tips, very long and incorporating bases of several autozooids, though their width may not exceed three or four zooids at any given place. Brood chambers progressively more swollen and wider nearer distal ends, near which their relatively narrow but elongate ooeciostomes are located. Ooeciostomes circular in cross section, variably tapered distally, except in some ending as a small flared lip.

Exterior walls perforated by round pseudopores with centripetally directed spines extending from surrounding wall. Pseudopores densely distributed on the surface of brood chambers, intermediate on exterior walls of recumbent portions of autozooids, and least abundant on peristomes.

Protoecia large (250 ± 26 µm, N = 3), hemispherical to domed button­shaped, with distal portion of ancestrula extending as a uniform tube with smaller diameter (117 ± 15 µm, N = 3) than in asexually budded autozooids. Distal­most portion of ancestrula elevated as a peristome, and first asexual autozooid budded from its undersurface and oriented either in the same direction as the ancestrula or diverging obliquely to right or left. Second generation of asexually budded autozooids originating against substratum, under distal end of first autozooid, then divergent to right and left. Each second generation autozooid establishing a gently curved, adnate multizooidal runner, generally three autozooids wide. Each divergent runner potentially dichotomously dividing into two distal, divergently curved, multizooidal runners as in parent generation. At irregularly distributed points on original or subsequent encrusting lobes of the colony, distal budding zone potentially dividing into two regions, one remaining encrusting and the other becoming completely encircled by exterior wall, establishing an erect portion of colony. Peristomes of autozooids in encrusting portions of colonies potentially much longer than on erect branches. Longest peristomes belonging to autozooids in deep recesses, such as interior surfaces of ridges in pectenids.

Tentacles clear, 14; lophophores small, distally flaring, conical; at maximum protrusion, bases of lophophores located within peristome, below level of aperture, in all material studied.

OCCURRENCE: This is a common, widespread, and highly variable species offshore of Rovinj. It occurs on a variety of hard substrata, from bivalve shells to Cellaria . Harmelin (1976) reported the species from shallowest waters to depths of at least 300 m and growing on a huge number of substrata from marine grasses to rock surfaces of caves.

DISTRIBUTION: E. deflexa is common in the eastern North Atlantic, from Arctic Norway southward and in the Mediterranean Sea.

MEASUREMENTS (SKELETAL): AD 130 ± 11 µm, 110–160 (8, 80), AS 676 ± 140, 400– 960 (5, 50), BrD 553 ± 74, 400–720 (5, 26), GL 2216 ± 128, 2040–2400 (3, 5), GW 828 ± 125, 660–960 (3, 5), OsD 85 ± 7, 80–95 (3, 5). (POLYPIDE): IH 0 ± 0 µm (2, 12), MD 28 ± 3, 25–30 (2, 3), LD 609 ± 108, 380– 720 (2, 14), TL 571 ± 85, 280–680 (2, 13).

Entalophoroecia robusta Harmelin, 1976 Figure 52E–G

Entalophoroecia robusta Harmelin, 1976: 116 .

Zabala, 1986: 636. Zabala and Maluquer, 1988:

168. DESCRIPTION (AMNH 1029): Colony erect

with bifurcating, radially symmetrical, rela­

tively heavily calcified and robust branches. Autozooidal boundaries clearly visible on colony surface. Autozooidal peristomes long, curved abruptly away from axis of branch but oriented relative to neighboring autozooids, with apertures relatively uniformly spaced.

Gonozooids not restricted to branch termini; brood chambers incorporating the bases of several adjacent autozooids. Ooeciopores circular in cross section, slightly small­ er in diameter than autozooidal peristomes, contiguous with base of autozooidal peristome, but shorter.

Exterior walls perforated by elongate oval pseudopores apparently lacking centripetally directed spines. Pseudopores least abundant on peristomes.

Primary zone of astogenetic change and encrusting portions of colonies not observed.

REMARKS: The species is much less abundant than Entalophoroecia deflexa in our material but can be readily distinguished because of its larger peristome diameters, the relatively wider and shorter ooeciopore, larg­ er branches, and perhaps also by greater regularity in placement of peristomes relative to one another.

DISTRIBUTION: This species is at present known only from the Mediterranean Sea, identified from the French and Spanish coasts, but Harmelin (1976) considers that it is more widely spread, being confused with other species of Entalophoroecia .

MEASUREMENTS (SKELETAL): AD 186 ± 13 µm, 160–200 (2, 20), AS 759 ± 144, 600– 1200 (2, 20), BrD 796 ± 107, 600–1000 (2, 20).

FAMILY PLAGIOECIIDAE CANU, 1918

GENUS PLAGIOECIA CANU, 1918

Plagioecia patina ( Lamarck, 1816) Figures 53A–F , 54

Figures

Fig. 52. A–D. Entalophoroecia deflexa. A. General aspect (AMNH 1027; 1 mm). B. Ooeciostome (center) (AMNH 1027; 0.1 mm). C. Pseudopores (AMNH 1027; 0.02 mm). D. Ancestrula (bottom center and early autozooids on Cellaria branch (AMNH 1028; 0.5 mm). E–G. Entalophoroecia robusta (AMNH 1029). E. General aspect (0.5 mm). F. Branch tip (0.5 mm). G. Pseudopores, more abundant on branch surface (left) than on (right) peristome (0.05 mm).

Fig. 53. A–F. Plagioecia patina. A. Colony with budded daughter colony (AMNH 947; 0.5 mm). B. Lateral view of colony with budded daughter colony (AMNH 947; 0.5 mm). C. Brood chamber (top) near colony margin (AMNH 1030; 0.5 mm). D. Brood chamber and (top center) distal ooeciostome with circular ooeciopore (AMNH 1030; 0.1 mm). E. Marginal zone of functional autozooids (right) and (left) nonfunctional autozooids with broken peristomes and terminal diaphragms (AMNH 1031; 0.2 mm). F. Pseudopores (AMNH 1032; 0.01 mm).

Fig. 54. Plagioecia patina. A. Ontogenetic increase in tentacle and introvert length: filled circles plot maximum tentacle length within lophophores (Y = 198.490 + 0.975X) and open circles plot lengths of exposed portions of introverts (Y = 2.685 + 0.440X). B. Ontogenetic increase in maximum lophophore diameter (Y = 268.652 + 0.630X).