Schizomavella noronhai ( Norman, 1909 ) Norman, 1909

Berning, Björn, 2012, Taxonomic notes on some Cheilostomata (Bryozoa) from Madeira, Zootaxa 3236, pp. 36-54 : 38-39

Schizomavella noronhai ( Norman, 1909) n. comb.

( Figs 2–5 , Table 1 )

Schizoporella noronhai Norman, 1909: 303 , pl. 41, fig. 1.

Material examined. Holotype: NHMUK 1911.10.1.1110, by monotypy, Norman collection (collected by A. C. de Noronha), Madeira, encrusting a telegraphic cable (no further information provided as regards depth and location).

Description. Colony encrusting, unilaminar, multiserial. Zooids quadrangular to polygonal, broad, separated by sutures on slightly raised, thin rims. Vertical walls with about 4 round communication pores per neighbouring zooid. Frontal shield only slightly convex proximally, gently rising towards the elevated orifice distally, entirely covered by polygonal pits separated by raised ridges and irregularly perforated centrally by several distinct pseudopores plus a series of marginal areolar pores. Primary orifice semi-elliptical to broadly horseshoe-shaped, slightly longer than wide, proximal margin straight with a broadly U-shaped sinus occupying almost half of total proximal width, condyles fairly narrow and gently sloping towards edges of sinus, distolateral autozooidal margin with 8 or rarely 9 oral spines, 4 in ovicellate zooids.

ZL ZW OL OW OvL OvW AL AW mean 671 550 122 105 207 230 73 44 Ovicell prominent, globular, flattened frontally, slightly broader than long, ooecium formed by distal zooid, the secondary calcification of which later marginally covers the calcified ectooecium; surface smooth, perforated by numerous suborbicular and rimmed pseudopores of approximately similar size, the proximal margin usually slightly raised, with elongated or fused pseudopores; ovicell opening transversely elongated and situated above primary orifice, not closed by the operculum.

Avicularia adventitious, monomorphic, elongate-elliptical with almost parallel lateral sides, usually paired or occasionally single, most often situated between orifice and lateral walls at some distance to distal zooecial border (directed laterally or proximolaterally), commonly with one or both avicularia in a more proximolateral (directed proximolaterally) or even central position (directed proximally); rostrum elongate D-shaped, distal uncalcified area rounded triangular, distolaterally demarcated by a rim of crenellate calcification, proximal area elliptical or Dshaped; crossbar complete, without columella.

Ancestrula not observed.

Remarks. The great number of spines, the surface topography of the frontal shield with its large pseudopores, and the large area of exposed ectooecium, again with numerous round pseudopores, distinguishes this species from most other recently described and figured Schizomavella species from the eastern Atlantic (e.g. Harmelin & d'Hondt 1992; Hayward & Thorpe 1995; Reverter-Gil & Fernández-Pulpeiro 1995, 1997; Hayward & Ryland 1999). The sister species of S. noronhai is certainly Schizomavella neptuni ( Jullien, 1883) , which also has 8–10 spines and the same avicularian and frontal-shield surface structure, and which occurs from the Bay of Biscay to the Gulf of Cádiz and the western Mediterranean and possibly also in the Azores. However, S. neptuni lacks the conspicuous frontal-wall pores, and the orificial sinus is distinctly narrower ( Jullien 1883: 511, pl. 14, fig. 34; Harmelin & d'Hondt 1992: 46, pl. 6, fig. C; Zabala et al. 1993: 75, figs 19–20). Schizomavella noronhai has hitherto been recorded only from Madeira.

Figures

FIGURES 2 – 5. Schizomavella noronhai (Norman, 1909) n. comb., holotype, NHMUK 1911.10.1.1110. 2, surface of mature colony with ovicellate zooids and adventitious avicularia. 3, close-up of ovicellate zooid. 4, zooids at the colony margin. 5, primary orifice. Scale bars: Figs 2, 4 = 200 µm; Fig. 3 = 100 µm; Fig. 5 = 20 µm.

Tables

TABLE 1. Measurements (in µm) of Schizomavella noronhai n. comb. For acronyms and abbreviations see Material and Methods.

SD min.	100 521	84 431	5 115	5 95	11 187	26 185	6 58	5 36
max.	887	764	130	112	219	267	80	52
n	20	20	20	20	8	8	20	20