Hemicyclopora multispinata ( Busk, 1861 )

Harmelin, Jean-Georges & Rosso, Antonietta, 2023, On some “ Hemicyclopora ” Norman, 1894 and “ Escharella ” Gray, 1848 species (Bryozoa, Cheilostomatida) from the Atlantic-Mediterranean region. Re-examination of their generic status and description of new species and a new genus, Zoosystema 45 (10), pp. 373-407 : 376

Hemicyclopora multispinata ( Busk, 1861)

( Fig. 1 A-C)

Lepralia multispinata Busk, 1861: 78 , pl. 32, figs 5, 6.

? Hemicyclopora multispinata – Cook 1968: 216. — Hayward & Ryland 1999: 146 (pars). — Ramalho et al. 2020b: 455, 457 (table 2), 459 (table 3).

Not Hemicyclopora multispinata – Norman 1909: 308, pl. 42, figs 6-7. — Nichols 1911: 21. — Harmelin 1976: 230, table 3 (= “E.” massiliana n. sp.). — Zabala 1986: 444. — Boronat Tormo 1987: 107, pl. 10A, B (= H. discrepans (Jullien in Jullien & Calvet, 1903)). — Zabala & Maluquer 1988: 126, fig. 283b (= H. discrepans ). — Rosso 1989: tables 3c, 4c, 6c, pl. 8, fig. A (= H. neatonensis n. sp.); 1996a: 195, 210, pl. 4, fig. A; 1996b: 60 (table 1) (= H. neatonensis n. sp.). — Di Geronimo et al. 1990, table 1. — López de la Cuadra & Garcia Gómez 1994: 11 –– Chimenz & Faraglia 1995: 40, pl. 2, figs A, B (= H. neatonensis n. sp.). — Morri et al. 1999: 733 (table 1). — Hayward & Ryland 1999, figs 46D, 49 (= “ H.” pytheasi n. sp. or H. celtica n. sp). — Chimenz Gusso et al. 2014: 172, fig. 88a-d (= H. neatonensis n. sp.). — Denisenko et al. 2016: 13 & table 1. — Rosso & Di Martino 2016: 579 (table 1).

TYPE LOCALITY. — Madeira.

MATERIAL EXAMINED. — Atlantic, Portugal, Madeira • Type. Dry specimen in slide 99.7.1.1802; NHMUK, Busk collection; labelled “ Mucronella peachii var. multispinata , one small, unfertile colony on a shell fragment, collected by J. Y. Johnson; macrophotos sent by Mary Spencer Jones”; 14.II.2022; here, Fig. 1C ).

REMARKS

The available optical photos of the type of H. multispinata ( Fig. 1C ) reveal a small specimen, in mediocre condition, without ovicells, but with an ancestrula apparently bearing 10 spines.Visible features of the orifices confirm the correctness of Busk’s figures ( Busk 1861, pl. 32, figs 5-6; here, Fig. 1A, B ) and original description (“… orifice arched, with an entire, straight lower lip; peristome raised, thick, forming a cup in front of the orifice; 8-10 marginal spines ”). Busk’s figure 6 shows an autozooid with six spines, but in figure 5 three autozooids bear at least eight spines ( Fig. 1A, B ). In both figures, orifices are slightly longer than broad, with a moderately concave proximal edge and an arched proximal thickening with a moderate vertical elevation. Therefore, the assertion by Hayward & Ryland (1999: 146) that the orifice of H. multispinata is characterized by a “ proximal edge produced medially as a prominent lip ” do not correspond to Busk’s description and figures. Their figures illustrating H. multispinata ( Hayward & Ryland 1999, figs 46D; 49) may actually correspond to one of the species treated below. Consequently, H. multispinata has often been erroneously recorded, particularly from the northern Atlantic and the Mediterranean (see below). The record of H. multispinata by Norman (1909: 308, pl. 42, figs 6-7) at Madeira (70 fathoms depth) is quite puzzling as this specimen is depicted with eight oral spines, an orifice with a proximal edge more ‘pouting’ than in H. polita , and also with large spatulate avicularia ( Norman 1909, pl. 42, fig. 7; here, Fig. 1E ). This latter feature obviously excludes this specimen from the genus Hemicyclopora as it is unlikely that Norman had misinterpreted the occurrence of an adjacent colony belonging to another, very different, species provided with large avicularia. A plausible hypothesis is that this specimen belongs to another family, and quite possibly to a species of the atlantisinid genus Bathycyclopora Berning, Harmelin & Bader, 2017 . This genus “superficially resembles the escharellid genera Hemicyclopora and Escharella ” ( Berning et al. 2017: 31). For example, B. suroiti Berning, Harmelin & Bader, 2017 , from Atlantis Seamount, has eight long oral spines, an orifice with a prominent proximal edge, tiny paired adventitious avicularia, poorly visible without SEM, and large spatulate interzooidal avicularia with a rostrum similar in shape to those illustrated by Norman (here, Fig. 1F, G ). Therefore, one may suppose that a deep-water species close to B. suroiti exists at Madeira and has been confused with H. multispinata by Norman (1909).

Cook (1968: 216) considered that H. multispinata was synonymous with H. canalifera (Busk, 1884) after examination of the types of both species. However, this synonymy was rejected by Berning & Spencer Jones (2023), who designated the specimen figured by Busk (1884: pl. 22, fig. 2) as the lectotype of Mucronella canalifera . The morphological features of an Azorean specimen from the collection of Jullien and Calvet listed as H. multispinata in the MNHN collections (MNHN-IB-2008-2436: Talisman 1883, Dr. 125, 13.VIII.1883, Fayal-Pico, 80-115 m), are visible at https:// www.mnhn.fr/fr/collections/collection-groups/marine-invertebrates/bryozoans-and-brachiopods/hemicyclopora) thanks to 10 SEM photos taken by B. Berning in 2012 (MNHN project RECOLNAT ANR-11-INBS-0004). This specimen, very different from the Busk’s type of H. multispinata , was assigned to H. canalifera by Berning & Spencer Jones (2023, fig. 5). Records of H. multispinata from boreal areas (e.g. Nichols 1911, Denisenko et al. 2016) are doubtful.

Figures

FIG. 1. — A, B, original figures of Lepralia multispinata Busk, 1861, from Madeira; part of colony with eight non-ovicellate zooids (A), distal part of a non-ovicellate zooid (B) illustrating the bases of six spines, the orifice shape and the proximal peristomial thickening; C, part of the type specimen of Lepralia multispinata (Busk collection 99.7.1.1802), with ancestrula and 11 non ovicellate zooids, photo courtesy of Mary Spencer Jones; D, E, Hemicyclopora multispinata (Busk, 1861) from Madeira, figured by Norman (1909, figs 6-7), ovicellate and non-ovicellate zooids, note the long spines and the orifice with a convex proximal edge of two zooids (D), and the large spatulate avicularia (E); F, G, Bathycyclopora suroiti Berning, Harmelin & Bader,2017.Origin: Atlantis Seamount, RV Suroit, Seamount 2, DW258, derivative of figures 12G and 12E (both SEM photos by JGH) in Berning et al. (2017). Scale bars: F, G, 200 µm.