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Rosso A. et al.
Rhamphostomella (?) prenanti – d’Hondt & Ben Ismail slightly displaced proximally (Figs 2E, F, H; 3C).
2008: 63. An elevated, pointed, slightly asymmetrical umbo
present on most autozooids (mostly obvious in
MATERIAL EXAMINED. — Algeria. Castiglione, 22.IV.1952, Fig. 2C, H); its surface evenly tuberculate, except
unique colony, holotype (MNHN, J. Picard collec- for the truncated, smooth, distal side.
tion).
Western Sicily. Egadi Islands, Marettimo Island, South of Avicularium single, often lacking, lateral-suboral
Bassana Point, sample EBE.4, 19 m depth, 4 fragments, on an inflated imperforate cystid; rostrum acute to
seemingly from a single, living, fertile colony (PMC. R. the frontal surface and laterally directed, typically
I. H. B9a). — Egadi Islands, north of the Levanzo Island, elongate triangular with a hooked tip; cross-bar
off Cape Grosso, samples ELE.7 and ELI.7, respectively complete, strong and slightly arched (Figs 2B, E;
sampled during summer and winter seasons, 17 m depth, 3A-C, F, G). Paired avicularia observed in a single
5 fertile and sterile fragments (PMC. R. I. H. B9a). zooid (Fig. 2G).
Case Catarinicchia section, early Pleistocene, sample
BC7, 1 specimen (PMC. R.I.Ps. B9a). Ovicell globular, prominent, recumbent on and
Central-eastern Sicily. Basal bioclastic layer of the slightly immersed in the frontal wall of the distal
Pianometa section, early Pleistocene, 1 fertile specimen zooid, slightly wider than long and restricted near
(PMC. R.I.Ps. B9b). the opening, overarching the zooidal primary ori-
North-eastern Sicily. East of Furnari, Contrada Inferno, fice (Figs 2E, F, H; 3C), seemingly semicleithral or
Barcellona Pozzo di Gotto Basin, middle-late Pliocene or cleithral sensu Ostrovsky (2008). It has an entirely
?early Pleistocene, sample MC.116, 1 specimen (PMC. membranous ectooecium and a calcified entooecium
R.I. B9c). sculptured by evenly distributed small pseudopores
located within depressions in between smooth
DESCRIPTION truncated tubercles; the proximal margin lined by
Colony encrusting multiserial and unilaminar, a thin slightly raised edge (Figs 2F; 3C).
orange to salmon in colour, loosely attached to the
substratum and elevated from it through regularly Communication of contiguous zooids through
spaced, mineralised, short, hollow, pillar-like struc- 12-20 pores irregularly arranged in longitudinal
tures emanating from the basal surfaces, mostly from band just below the midline of the vertical walls
the periphery, of each zooid (Fig. 2D). between adjacent zooids (Fig. 2D).
Autozooids oval to rhomboidal, slightly convex, Ancestrula not observed.
separated by distinct grooves and a thin raised
suture, usually leaving irregularly-shaped lacunae Measurements
where three zooids come into contact (Fig. 2A, F). Zooidal lenght: 637 ± 66 (549; 858) n = 34; zooidal
Frontal wall coarsely tuberculate with a peripheral width: 412 ± 57 (315; 582) n = 34; orifice length:
row of relatively large, elongated pores plus 18-28 124 ± 8 (108; 139) n = 34; orifice width: 152 ± 12
rounded infundibular ones, scattered on the frontal (128; 179) n = 34; ovicell length: 308 ± 44 (246;
surface (Fig. 2A, B). Orifice located very distally, 368) n = 9; ovicell width: 379 ± 18 (363; 408) n =
slightly wider than long with a semicircular distal 9; avicularial length: 158 ± 20 (117; 183) n = 11;
rim, lined by a thin distal shelf, and a straight proxi- avicularial width: 90 ± 15 (63; 109) n = 11.
mal lip; sinus very shallow and wide, occupying
more than half of the proximal edge, flanked by VARIABILITY
squared and shallow slightly denticulate condyles The above description is exclusively based on living
(Figs 2B, C, E; 3D). A thin peristome sometimes specimens. Several skeletal characters contribute
develops, raised on the anter, shallowing laterally to the intraspecific variability: the size of zooids
to level orifice at proximal corners. One to three, and the zooidal outline and morphology, includ-
usually two, inconspicuous slender spines, not ing calcification of the frontal wall and sculpture
articulated at the base, characteristically very dis- development; the presence and strength of the
tal at each side, or asymmetrical (Figs 2A-E; 3A, suboral umbo; the size and proportions of orifices;
B, D), two persisting in ovicellate zooids, usually the number of oral spines (up to 4 in few zooids and
460 ZOOSYSTEMA • 2010 • 32 (3)
