taxonID	type	description	language	source
03D6E5354F142828FF28FADEFDB93F94.taxon	diagnosis	DIAGNOSIS. — As for the genus (see below), but frontal wall including a pseudoporous or a centrally imperforate area, besides the row of marginal areolae.	en	Rosso, Antonietta, Sciuto, Francesco, Sinagra, Alessandro (2010): Bertorsonidra n. gen. (Bryozoa, Cheilostomata) for Tremopora prenanti Gautier, 1955, a rare species from the Mediterranean. Zoosystema 32 (3): 457-467, DOI: 10.5252/z2010n3a7, URL: http://www.bioone.org/doi/abs/10.5252/z2010n3a7
03D6E5354F142823FF7EF996FDAB3BB7.taxon	diagnosis	DIAGNOSIS. — Colony encrusting attached to the substratum through pillar-like structures emanating from the basal surface. Autozooids loosely arranged and leaving interzooidal spaces. Frontal wall pseudoporous bordered by marginal pores. Orifice semicircular with a proximal sinus and lateral condyles. Peristome inconspicuous. Spines present, not articulated at the base, two persisting in ovicellate zooids. Suboral umbo sporadic but characteristic. Avicularia present, typically single, lateral-suboral on an inflated cystid. Ovicell prominent with uncalcified ectooecium and a granular, evenly pseudoporous entooecium. Interzooidal communication through uniporous septulae arranged in a band in the vertical walls.	en	Rosso, Antonietta, Sciuto, Francesco, Sinagra, Alessandro (2010): Bertorsonidra n. gen. (Bryozoa, Cheilostomata) for Tremopora prenanti Gautier, 1955, a rare species from the Mediterranean. Zoosystema 32 (3): 457-467, DOI: 10.5252/z2010n3a7, URL: http://www.bioone.org/doi/abs/10.5252/z2010n3a7
03D6E5354F142823FF7EF996FDAB3BB7.taxon	materials_examined	TYPE SPECIES. — Tremopora prenanti Gautier, 1955 by present designation.	en	Rosso, Antonietta, Sciuto, Francesco, Sinagra, Alessandro (2010): Bertorsonidra n. gen. (Bryozoa, Cheilostomata) for Tremopora prenanti Gautier, 1955, a rare species from the Mediterranean. Zoosystema 32 (3): 457-467, DOI: 10.5252/z2010n3a7, URL: http://www.bioone.org/doi/abs/10.5252/z2010n3a7
03D6E5354F142823FF7EF996FDAB3BB7.taxon	etymology	ETYMOLOGY. — Th e name is an anagram of Robertsonidra, a closely related genus.	en	Rosso, Antonietta, Sciuto, Francesco, Sinagra, Alessandro (2010): Bertorsonidra n. gen. (Bryozoa, Cheilostomata) for Tremopora prenanti Gautier, 1955, a rare species from the Mediterranean. Zoosystema 32 (3): 457-467, DOI: 10.5252/z2010n3a7, URL: http://www.bioone.org/doi/abs/10.5252/z2010n3a7
03D6E5354F142823FF7EF996FDAB3BB7.taxon	materials_examined	MATERIAL EXAMINED. — Algeria. Castiglione, 22. IV. 1952, unique colony, holotype (MNHN, J. Picard collection). Western Sicily. Egadi Islands, Marettimo Island, South of Bassana Point, sample EBE. 4, 19 m depth, 4 fragments, seemingly from a single, living, fertile colony (PMC. R. I. H. B 9 a). — Egadi Islands, north of the Levanzo Island, off Cape Grosso, samples ELE. 7 and ELI. 7, respectively sampled during summer and winter seasons, 17 m depth, 5 fertile and sterile fragments (PMC. R. I. H. B 9 a). Case Catarinicchia section, early Pleistocene, sample BC 7, 1 specimen (PMC. R. I. Ps. B 9 a). Central-eastern Sicily. Basal bioclastic layer of the Pianometa section, early Pleistocene, 1 fertile specimen (PMC. R. I. Ps. B 9 b).	en	Rosso, Antonietta, Sciuto, Francesco, Sinagra, Alessandro (2010): Bertorsonidra n. gen. (Bryozoa, Cheilostomata) for Tremopora prenanti Gautier, 1955, a rare species from the Mediterranean. Zoosystema 32 (3): 457-467, DOI: 10.5252/z2010n3a7, URL: http://www.bioone.org/doi/abs/10.5252/z2010n3a7
03D6E5354F142823FF7EF996FDAB3BB7.taxon	description	North-eastern Sicily. East of Furnari, Contrada Inferno, Barcellona Pozzo di Gotto Basin, middle-late Pliocene or? early Pleistocene, sample MC. 116, 1 specimen (PMC. R. I. B 9 c). DESCRIPTION Colony encrusting multiserial and unilaminar, orange to salmon in colour, loosely attached to the substratum and elevated from it through regularly spaced, mineralised, short, hollow, pillar-like structures emanating from the basal surfaces, mostly from the periphery, of each zooid (Fig. 2 D). Autozooids oval to rhomboidal, slightly convex, separated by distinct grooves and a thin raised suture, usually leaving irregularly-shaped lacunae where three zooids come into contact (Fig. 2 A, F). Frontal wall coarsely tuberculate with a peripheral row of relatively large, elongated pores plus 18 - 28 rounded infundibular ones, scattered on the frontal surface (Fig. 2 A, B). Orifice located very distally, slightly wider than long with a semicircular distal rim, lined by a thin distal shelf, and a straight proximal lip; sinus very shallow and wide, occupying more than half of the proximal edge, flanked by squared and shallow slightly denticulate condyles (Figs 2 B, C, E; 3 D). A thin peristome sometimes develops, raised on the anter, shallowing laterally to level orifice at proximal corners. One to three, usually two, inconspicuous slender spines, not articulated at the base, characteristically very distal at each side, or asymmetrical (Figs 2 A-E; 3 A, B, D), two persisting in ovicellate zooids, usually slightly displaced proximally (Figs 2 E, F, H; 3 C). An elevated, pointed, slightly asymmetrical umbo present on most autozooids (mostly obvious in Fig. 2 C, H); its surface evenly tuberculate, except for the truncated, smooth, distal side. Avicularium single, often lacking, lateral-suboral on an inflated imperforate cystid; rostrum acute to the frontal surface and laterally directed, typically elongate triangular with a hooked tip; cross-bar complete, strong and slightly arched (Figs 2 B, E; 3 A-C, F, G). Paired avicularia observed in a single zooid (Fig. 2 G). Ovicell globular, prominent, recumbent on and slightly immersed in the frontal wall of the distal zooid, slightly wider than long and restricted near the opening, overarching the zooidal primary orifice (Figs 2 E, F, H; 3 C), seemingly semicleithral or cleithral sensu Ostrovsky (2008). It has an entirely membranous ectooecium and a calcified entooecium sculptured by evenly distributed small pseudopores located within depressions in between smooth truncated tubercles; the proximal margin lined by a thin slightly raised edge (Figs 2 F; 3 C). Communication of contiguous zooids through 12 - 20 pores irregularly arranged in longitudinal band just below the midline of the vertical walls between adjacent zooids (Fig. 2 D). Ancestrula not observed. Measurements Zooidal lenght: 637 ± 66 (549; 858) n = 34; zooidal width: 412 ± 57 (315; 582) n = 34; orifice length: 124 ± 8 (108; 139) n = 34; orifice width: 152 ± 12 (128; 179) n = 34; ovicell length: 308 ± 44 (246; 368) n = 9; ovicell width: 379 ± 18 (363; 408) n = 9; avicularial length: 158 ± 20 (117; 183) n = 11; avicularial width: 90 ± 15 (63; 109) n = 11. VARIABILITY The above description is exclusively based on living specimens. Several skeletal characters contribute to the intraspecific variability: the size of zooids and the zooidal outline and morphology, including calcification of the frontal wall and sculpture development; the presence and strength of the suboral umbo; the size and proportions of orifices; the number of oral spines (up to 4 in few zooids and 5 in a single one on the type material) and, most obviously, the presence or absence of avicularia in large parts of the colony. Differences in skeletal preservation caused by biostratinomic mechanical stresses and by partial dissolution and extensive re-crystallization during fossilization often hamper the reliable attribution of fossil specimens to species-level taxa, as recently remarked by Berning (2006). Nevertheless, in the fossil specimens of R. prenanti, the well-preserved distinctive frontal wall morphology, together with the partial or complete preservation of orificial spines and even of condyles (usually absent from most zooids, seemingly due to their thinness and / or a different mineralogical composition) on at least single zooids in a colony, allow for an identification to species level. Representatives of the fossil populations appear very close to the living ones. Only few differences between the fossil and the Recent specimens have been detected, which have been considered as intraspecific variability. They include the slightly distal position of the lateral-suboral avicularia, which are laterally or slightly disto-laterally directed; and the relatively depressed ovicells, being less distinct from the distal zooid frontal wall (seemingly due to secondary calcification), tending to form a more V-shaped proximal border. Interestingly, fossil specimens from Pianometa exhibit some ovicells, which have prominences in their central part, thus being somewhat reminiscent of the tubercolate ovicells of “ Ramphostomella argentea ”, as figured by Zabala & Maluquer (1988). Nevertheless, and apart from this character, both diagnosis and drawing of Zabala & Maluquer (1988: 123, fig. 275), are probably a conflation.	en	Rosso, Antonietta, Sciuto, Francesco, Sinagra, Alessandro (2010): Bertorsonidra n. gen. (Bryozoa, Cheilostomata) for Tremopora prenanti Gautier, 1955, a rare species from the Mediterranean. Zoosystema 32 (3): 457-467, DOI: 10.5252/z2010n3a7, URL: http://www.bioone.org/doi/abs/10.5252/z2010n3a7
03D6E5354F142823FF7EF996FDAB3BB7.taxon	discussion	REMARKS The species was formerly erected by Gautier (1955) as Tremopora prenanti although subsequently synonymised by the same author (Gautier 1962: 261) with Schizoporella argentea Hincks, 1881 from the Indo-Pacific, following personal suggestions by M. Prenant and A. B. Hastings. Nevertheless, the Mediterranean species is only reminiscent of Robertsonidra argentea as described and figured by Ryland & Hayward (1992: 261, fig. 19 b) and by Tilbrook (2006: 261, pl. 57 E, F). In fact, Bertorsonidra prenanti n. comb., exhibiting a wide shallow sinus laterally marked by squared condyles, clearly differs from R. argentea, which is characterized by a primary orifice with a deep concave sinus not flanked by condyles. Furthermore, R. argentea shows two different kinds of lateral-suboral avicularia: 1) a smaller and relatively more common one opposite to the umbo, acute to the frontal plane, distally hooked and laterally directed; and 2) a larger and rarer but more diagnostic one, normal to the frontal plane and proximolaterally directed. In contrast, a single avicularium type seems to be present in the Mediterranean species: lateral suboral, laterally directed, with a hooked rostrum on a large and prominent cystid. Further differences include the colour of living tissue (yellowish-white in R. argentea), the zooidal outline, and the number, extent and morphology of the marginal pores. But most important differences relate to the presence of an evenly porous zooidal frontal wall in B. prenanti n. comb. (see discussion below).	en	Rosso, Antonietta, Sciuto, Francesco, Sinagra, Alessandro (2010): Bertorsonidra n. gen. (Bryozoa, Cheilostomata) for Tremopora prenanti Gautier, 1955, a rare species from the Mediterranean. Zoosystema 32 (3): 457-467, DOI: 10.5252/z2010n3a7, URL: http://www.bioone.org/doi/abs/10.5252/z2010n3a7
03D6E5354F142823FF7EF996FDAB3BB7.taxon	materials_examined	The attribution of B. prenanti n. comb. to the genus Ramphostomella, as suggested by Gautier (1962) and dubitatively by d’Hondt & Ben Ismail (2008) after examination of the unique known specimen from Algeria, is precluded. The genus Ramphostomella, in fact, possesses a centrally imperforate, umbonulomorph frontal shield and pronounced ridges between marginal areolae, markedly different orifice and ovicell (see Gordon & Grischenko 1994). In contrast, a strikingly similar morphological appearance and several characters are actually shared with species of the genus Robertsonidra Osburn, 1952, except for the pseudoporous lepraliomorph frontal wall, that is not the case for Robertsonidra. Consequently, as none of the already established genera seems to share all the morphological features observed in the examined material Bertorsonidra n. gen. is here proposed to accommodate the species described by Gautier. Particularly, the presence of pores in the frontal wall has been considered enough for erecting the new genus, somewhat paralleling the criteria adopted for separating couples of confamiliar genera, such as the couple formed by Therenia David & Pouyet, 1978 and Herentia Gray, 1848 within the Escharinidae Tilbrook, 2006 (see Berning et al. 2008), and that formed by Buffonellaria Canù & Bassler, 1917 and Pourtalesella Winston, 2005 within the Celleporidae Johnston, 1838 (see Winston 2005, but also Berning & Kuklinsky 2008). Consequently, it could be suggested that also Robertsonidra and Bertorsonidra n. gen., sharing most of their characters and differing for the nature of their frontal walls belong to the same family. Nevertheless, as the genus Robertsonidra, including at least seven species, mostly from the Indo-Pacific area (Bock 2002, but see above), had remained systematically unplaced (see Tilbrook 2006: 261), the erection of a new family Robertsonidridae n. fam. is here suggested for accommodating both Robertsonidra and Bertorsonidra n. gen. The new family shares some features, such as the concave to widely sinuate primary orifice and the frontal avicularia, with the Bitectiporidae MacGillivray, 1895 (as reported by Hayward & Ryland 1999 and Ramalho et al. 2008) but differs for the ovicells with calcified entoecium and ectooecium, which remain unfused. In contrast, although special studies aimed to describe ovicells in both genera are needed, both Robertsonidra and Bertorsonidra n. gen. seem to possess ovicells with an entirely uncalcified ectoecium and appear consequently comparable to those in the family Schizoporellidae Levinsen, 1909, mostly those of species belonging to the genus Schizoporella Hincks, 1877. FUNCTIONAL MORPHOLOGY Colonies of B. prenanti n. comb. are loosely attached to their substratum through hollow, pillar-like structures (Figs 3 D; 4 A), already described and figured by Gautier (1955: figs 7, 8), which emanate from the basal surfaces of each zooid. Th ese structures, mostly originating from the zooid periphery, elevate the basal surface of the colony some tens of micrometers above the substratum leaving a fissure-space above the algal tissue. Furthermore, it has been observed that the length of the rhizoidal pillars changes seemingly to better adapt the relatively thick and large colonial modules (zooids can reach about 900 Μm in length and 600 Μm in width: see measurements) to the curving or irregularly uneven morphology of the colonised surfaces. Finally, zooids are loosely connected each other and more or less wide lacunae exist in between them. All these features allow a certain articulation or at least some constructional flexibility to be attained. Consequently, colonies are able to grow nearly flat, thus partly levelling the irregularities of the colonised surfaces, when encrusting rough substrata, and to cover surfaces which are flexible or fleshy for the presence of soft tissues possibly without being particularly dangerous or lethal for the overgrown organism, due to their loose attachment. Th e presence of basal pillar-like attachment structures is not exclusive of B. prenanti n. comb. but has been observed also in similar, possibly related species, such as those belonging to Robertsonidra (see Robertson 1908; Tilbrook 2006). Furthermore, comparable basal extensions are present in species of the Hiantoporidae Hiantopora and the Microporidae Mollia (Fig. 4 B, AR pers. obs.), as already observed by Gautier (1955) himself and Berning (2006).	en	Rosso, Antonietta, Sciuto, Francesco, Sinagra, Alessandro (2010): Bertorsonidra n. gen. (Bryozoa, Cheilostomata) for Tremopora prenanti Gautier, 1955, a rare species from the Mediterranean. Zoosystema 32 (3): 457-467, DOI: 10.5252/z2010n3a7, URL: http://www.bioone.org/doi/abs/10.5252/z2010n3a7
03D6E5354F142823FF7EF996FDAB3BB7.taxon	distribution	DISTRIBUTION	en	Rosso, Antonietta, Sciuto, Francesco, Sinagra, Alessandro (2010): Bertorsonidra n. gen. (Bryozoa, Cheilostomata) for Tremopora prenanti Gautier, 1955, a rare species from the Mediterranean. Zoosystema 32 (3): 457-467, DOI: 10.5252/z2010n3a7, URL: http://www.bioone.org/doi/abs/10.5252/z2010n3a7
03D6E5354F142823FF7EF996FDAB3BB7.taxon	description	Noteworthy, the same kind of substratum was utilised by the three specimens of B. prenanti n. comb. found in fossil assemblages, which can be interpreted as living in a depth range deeper than 10 - 15 m and shallower than about 40 m. Particularly, the Pianometa colony was one of the extremely rare bryozoans from bioclastic cobblestones rich in centimetre- to decimetre-sized rhodoliths, and encrusted a corallinacean alga. Rhodoliths, whose nuclei consist of large fragments of the scleractinian Cladocora caespitosa (Linnaeus, 1767), were deposited in pyroclastite layers in very shallow waters (Pedley et al. 2001; AR pers. obs.). Similarly, the colony from Contrada Inferno along the Mazzarrà stream from NE Sicily, was found on a sub-spherical rhodolith sampled in a polymictic conglomerate layer, including pebbles and cobbles, sometimes coated by algae and rarely colonised by bryozoans (AR pers. obs.). Finally, the colony from the Belice section comes from silty-sandy layers, relatively rich in bioclasts, small rhodoliths and algal coatings on large mollusc shells, interpreted as derived from a Coastal Detritic Biocoenosis (sensu Pérès & Picard 1964) developed at about 40 m depth. Bryozoans include dominant Cellaria spp. internodes, together with Reteporella couchii (Hincks, 1878), Smittina cervicornis (Pallas, 1766), Pentapora fascialis (Pallas, 1766), Entalophoroecia deflexa (Couch, 1844), Platonea stoechas Harmelin, 1976 and Buskea nitida (Heller, 1867). Some other species, such as lichenoporids, Copidozoum planum (Hincks, 1880), C. tenuirostre (Hincks, 1880) and Micropora coriacea (Johnston, 1847) were found, also encrusting corallinaceans (Di Geronimo et al. 1994). From the above reported data, it follows that B. prenanti n. comb. seems to have a restricted geographic range and that it is extremely rare both in the geological past and nowadays. Interestingly, the species has maintained sensibly unaltered its ecological requirements through time, being selective of the Coralligenous Biocoenosis sensu Pérès & Picard (1964), although seemingly not excluded from other bioconcretions. Such a feature makes this species an useful tool for palaeoecological inferences. The stratigraphic range of B. prenanti n. comb. includes at least the middle part of the Early Pleistocene, as the Pianometa and the Belice layers were presumably deposited during the Emilian (Pedley et al. 2001) and the Sicilian (see Sprovieri & Cusenza 1972; Di Geronimo et al. 1994), respectively. Nevertheless, it could not be excluded that the species appeared earlier than this. The B. prenanti n. comb. bearing layers from the Contrada Inferno have not been dated due to the absence of stratigraphic markers, but sedimentation in the area (Barcellona Pozzo di Gotto Basin) became in the Early Pleistocene and locally date back since the Middle-Late Pliocene (Messina 2003).	en	Rosso, Antonietta, Sciuto, Francesco, Sinagra, Alessandro (2010): Bertorsonidra n. gen. (Bryozoa, Cheilostomata) for Tremopora prenanti Gautier, 1955, a rare species from the Mediterranean. Zoosystema 32 (3): 457-467, DOI: 10.5252/z2010n3a7, URL: http://www.bioone.org/doi/abs/10.5252/z2010n3a7
