Bathycyclopora, Berning & Harmelin & Bader & Cibio, 2017

Berning, Björn, Harmelin, Jean-Georges & Bader, Beate, 2017, New Cheilostomata (Bryozoa) from NE Atlantic seamounts, islands, and the continental slope: evidence for deep-sea endemism, European Journal of Taxonomy 347, pp. 1-51 : 31-32

Genus Bathycyclopora gen. nov.

urn:lsid:zoobank.org:act:E45D211D-BAC1-41CD-8AC5-458335BE6A69

Type species

Phylactella vibraculata Calvet, 1931 .

Diagnosis

Colony encrusting, unilaminar, multiserial, budding intrazooidal. Zooidal frontal shield umbonuloid, imperforate except for a row of marginal pores; entire zooidal surface of interior calcification except for the proximal and distolateral gymnocystal orifice margins; lateral walls generally extensive, with a single large pore chamber per neighbouring zooid, septular pore round, encompassed by a large cryptocystal area, a fine band of gymnocystal calcification delimiting each pore chamber from the neighbouring one. Orifice D-shaped or rather square, with condyles, an immersed distal shelf may be present; oral spines present. Potentially maternal zooids slightly dimorphic, with a distal gap between spines, ooecium produced by the zooid distal to the maternal one, hyperstomial, recumbent on the distal zooid’s frontal shield; ectooecium reduced to a thin frame surrounding the entire ooecial base; endooecium entirely calcified, imperforate; not closed by operculum (acleithral). Adventitious and interzooidal avicularia present. Ancestrula tatiform, opesia extensive, with a slight distal constriction; gymnocyst relatively narrow all around, cryptocyst absent.

Etymology

The name alludes to its bathyal habitat, and is combined with the latter part of the name of the genus Hemicyclopora , which it superficially resembles. Gender feminine.

Remarks

Bathycyclopora gen. nov. superficially resembles the romancheinid genera Hemicyclopora and Escharella , but differs from both in having (i) well-developed lateral walls with just one communication pore per neighbouring zooid; (ii) adventitious and interzooidal avicularia; (iii) a partially calcified ectooecium; and (iv) a simple tatiform ancestrula in which a cryptocyst is absent. The new genus differs from Atlantisina gen. nov. in the presence of avicularia, in the distinctly less developed ectooecium, and lateral walls that are predominantly composed of cryptocyst and which contain distinctly smaller communication pores. Moreover, whereas non-reproducing zooids and maternal zooids are monomorphic in Atlantisina gen. nov. (all zooids have the potential to eventually produce ovicells and have a distal gap between the oral spines to accommodate the ooecial aperture), the oral spines in Bathycyclopora gen. nov. are evenly distributed around the orifice in non-reproducing zooids, whereas a central gap exists only in potentially maternal zooids (not all of these zooids necessarily produce an ovicell). Moreover, the ooecium in Bathycyclopora gen. nov. is not a kenozooid produced by the maternal zooid as in Atlantisina gen. nov. but is formed by the zooid distal to the maternal one. The distal septular pore in Bathycyclopora gen. nov. is not as raised as in Atlantisina gen. nov. and is involved in budding a distal zooid or interzooidal avicularium, whereas in Atlantisina gen. nov. only an ooecium may be produced from this pore and it remains visible above the level of the frontal shield of the distal zooid throughout ontogeny in case no ovicell is formed. The structure of the ooecium is, however, very similar in both genera, although the ectooecium is less well developed in Bathycyclopora gen. nov.

The only two species in the genus are geographically restricted to central Atlantic islands (Azores) and seamounts (Atlantis). They have been recorded from the upper bathyal slope (400–600 m).