Stephanotheca monoecensis ( Calvet, 1927 ) Calvet, 1927

Reverter-Gil, Oscar, Souto, Javier & Fernández-Pulpeiro, Eugenio, 2012, A new genus of Lanceoporidae (Bryozoa, Cheilostomata), Zootaxa 3339, pp. 1-29 : 19-22

Stephanotheca monoecensis ( Calvet, 1927) n. comb.

( Figs 5, 8 , 40–49 ; Table 6 )

Schizoporella ambita var. monoecensis Calvet, 1927: 503 , fig. 3.

Schizomavella monoecensis (Calvet) : Gautier 1962: 145; Zabala 1986: 477, figs. 163, 164b; Zabala & Maluquer 1988: 132, fig. 298.

Schizomavella ochracea (Hincks) : Hayward & Ryland 1999, fig. 132 B.

Not Schizomavella monoecensis (Calvet) : Poluzzi & Rosso 1988: 91, pl. 4, fig. 3.

Material examined. Lectotype (designated here): MOM 42-1421: St. 140, Cap d’Ail, 30–40 m; Coll. Calvet. Paralectotypes (designated here): MOM 42-1515: St. I, environs de Monaco; Coll. Calvet; MOM 42-1276: St. 60, near Cap Martin, 50–60 m; Coll. Calvet; MNHN 5946: Cap d’Ail, 30–40 m; Coll. Calvet. Other Material Examined: MNHN 2356 (part: two small colonies): Bonifacio Travailleur, 1881, D.24 (2ª ser.) 55– 77 m. Coll. Calvet; MNHN 2378: Nice. Travailleur, 11/7/ 1881, 49 m. Coll. Jullien; MNHN 2383: Marseille, Coll. Jullien; MNHN 4103: no other data, Coll. Calvet; MNHN 11143, MNHN 11151, MNHN 11153, MNHN 11192, MNHN 11216 (part): Marseille, Coll. Gautier; MNHN 11190: Villefranche, Coll. Gautier; NHMUK 1888.11.9.29: Capri (figured by Hayward & Ryland, 1999, fig. 132 B).

Description. Colony forming broad irregular crusts, multilaminar, often large, orange. Autozooids in regular series in basal layer, losing orientation in successive layers. Rectangular to irregularly shaped in successive layers, separated by fine raised sutures. Frontal shield flat, covered by small rounded nodules, those near the orifice forming a weak proximolateral peristomial ridge. Frontal shield evenly perforated by small, circular pseudopores; marginal pores elongate and more conspicuous in older zooids. Uniporous septula. Primary orifice with the same characters as S. ochracea but larger. Large central avicularium, semielliptical to rounded-rectangular or subtriangular, in almost every zooid; placed in a central depression; crossbar complete, oval palatal foramen; mandible proximally directed. Gigantic avicularia lacking. Ovicell globular, frontally flattened, subimmersed. A wide, flat, circular area of ectooecium with rounded, elongate or irregular pseudopores, these larger at the periphery; secondary calcification of distal zooid forming a crown of prominent conical nodules encircling the exposed ectooecial area, frequently interrupted just over the orifice, showing a fine longitudinal suture; ovicell can also become covered by secondary calcification encroaching from adjacent zooids. Primary orifice of ovicellate zooids dimorphic, wider than orifice in non-ovicellate zooids and with smaller sinus; concealed by the concave proximal margin of the ovicell that extends to the proximolateral corners of the orifice; ovicell cleithral. Ancestrula unknown.

SD, Standard deviation; N, number of measurements.

Remarks. Stephanotheca monoecensis was described by Calvet (1927) as a variety of Schizoporella ambita (= S. watersi ), from material collected off Monaco. The original label has ‘ var. monaecensis ’, which would be the logical name; however, when published, it appeared as monoecensis , which is therefore the valid spelling. Later, Gautier (1962) raised the variety to species level, placing it in the genus Schizomavella . This author also added new data characterizing the species, but considered that its orifice is similar to S. rudis (= S. watersi ) and could instead be a variety of this species. We have revised Calvet’s (1927) original material held in MOM and MNHN and have chosen a lectotype and paralectotypes. SEM proves that the primary orifice of S. monoecensis and S. watersi are actually very different. In contrast, the primary orifice of the type material of S. monoecensis is similar that observed in the type material of S. ochracea , except for its larger size. However, the position, shape and size of the suboral avicularium are different in both species. In the holotype of S. ochracea it is small, oval to lanceolate and placed near the orifice, and is sometimes substituted by a gigantic avicularium; in the type material of S. monoecensis it is larger, subrectangular, placed in a depression in the centre of the zooid, and never gigantic. However, the shape of the avicularium in this species seems to vary considerably, from that exhibited in the types to others that are subtriangular, rounded or even oval. In a photograph of material collected in the area of Marseille ( Fig. 47 ), sent to us by J.-G. Harmelin, two avicularia of a noticeably different size in two contiguous zooids can be seen, one of them being closer to the type of monoecensis and another more similar to the type of ochracea . Also, in the record by Zabala (1986) the avicularia are noticeably smaller than in the type material. Finally, in the material illustrated in the Synopsis of the British Fauna ( Hayward & Ryland 1999), actually from Capri (P.J. Hayward, pers. comm.), the avicularium is smaller and oval. Ovicell characters are equivocal. The holotype of S. ochracea has only one ovicell, globular and prominent, while in the material cited by López de la Cuadra (1991) the ovicell is rather immersed. Similar variation also appears in different material of S. monoecensis . Finally, zooids and primary orifices are clearly larger in S. monoecensis .

Stephanotheca barrosoi , a species also exhibiting multilaminar colonies, differs from S. monoecensis in its oval primary orifice, the small avicularium close to the orifice, and the sporadic presence of vicarious avicularia.

Figures

FIGURES 1 – 8. Ovicell development in Stephanotheca. 1, communication pore between the ooecium-producing zooid and the coelomic cavity of the ooecium (arrow) (S. barrosoi n. sp.). 2, calcification of ectooecium and beginning of the calcification of entooecium (S. watersi n. sp.). 3, calcified ooecial floor (S. ochracea n. comb.). 4, developing ooecia (S. watersi n. sp.). 5, developing ooecium (S. monoecensis n. comb.). 6, central suture of the ectooecium (arrow) (S. barrosoi n. sp.). 7, complete ovicell, ooecial floor, and a partially broken ovicell showing ectooecial pseudopores (S. watersi n. sp.). 8, secondary calcification growing over the central porous area (S. monoecensis n. comb.).

FIGURES 40 – 44. Stephanotheca monoecensis (Calvet, 1927) n. comb. (lectotype: MOM 42 - 1421). 40, view of the colony; 41, primary orifice; 42, primary orifice and central avicularium; 43, ovicellate zooid. 44, view of the colony with autozooids and ovicellate zooid.

FIGURES 45 – 49. Stephanotheca monoecensis (Calvet, 1927) n. comb. 45, view of a colony (MNHN 2378); 46, developing ovicell and subtriangular avicularia (MNHN 11192); 47, ovicellate and non-ovicellate zooids with two different avicularia (photo by J. - G. Harmelin); 48, primary orifice (MNHN 11151); 49, primary orifice (MNHN 2378).

Tables

TABLE 6. Measurements (in mm) of Stephanotheca monoecensis (Calvet, 1927) n. comb. (lectotype and three other colonies).

	Mean	SD	Minimum	Maximum	N
Autozooid length	0.577	0.0549	0.454	0.694	40
Autozooid width	0.434	0.0535	0.325	0.569	40
Orifice length	0.141	0.0088	0.122	0.156	40
Orifice width	0.138	0.0072	0.125	0.152	40
Adventitious avicularium length	0.141	0.0124	0.119	0.182	40
Adventitious avicularium width	0.116	0.0141	0.084	0.143	40
Ovicell length	0.307	0.0180	0.277	0.325	8
Ovicell width	0.385	0.0167	0.366	0.411	8
Ovicell orifice length	0.140	0.0021	0.138	0.142	4
Ovicell orifice width	0.164	0.0042	0.161	0.169	4
Pseudorous area length	0.200	0.0359	0.150	0.245	8
Pseudorous area width	0.246	0.0186	0.219	0.277	8