Parkermaijella corrugata, Branch & Hayward, 2005

Branch, M. L. & Hayward, P. J., 2005, New species of cheilostomatous Bryozoa from subantarctic Marion and Prince Edward Islands, Journal of Natural History 39 (29), pp. 2671-2704 : 2690-2693

ParkermaIJella corrugata sp. nov.

( Figure 9 A–D)

Material

Holotype: St. 38 Marion Island (46 ° 58 9 S, 37 ° 59 9 E), 190–210 m, SAM A27559 . Paratype: St. 17 Marion Island (46 ° 41 9 S, 37 ° 49 9 E), 335–375 m, SAM A27558 .

Other material. St. 25 Marion Island (46 ° 50 9 S, 37 ° 54 9 E), 140 m, SAM A27500 ; St. 53 Marion Island (46 ° 55 9 S, 37 ° 33 9 E), 606–775 m, SAM A27570 .

Description

Colony unilaminar, forming partly attached curled sheets. Autozooids in regular, spreading rows, broad, rectangular to irregularly polygonal; 0.5–0.7X 0.35–0.45 mm; frontal shield flat to slightly convex, coarsely granular, with a corrugated, reticulate surface; large circular marginal pores only, occasionally two rows distally. Primary orifice about as wide as long, 0.13 mm, with a broad, shallow sinus occupying about two-thirds of its proximal width; condyles small, blunt. Four distal, oral spines present, usually lost in later ontogeny, and obscured in ovicelled autozooids. Each autozooid with one small adventitious avicularium medio-proximal to the orifice, on a low prominence, the rostrum elongate oval, slightly acute to distal plane, directed proximally; crossbar slender, palate with an extensive foramen; dimorphic avicularia, as long as the orifice and with a lingulate rostrum, replacing the small type in some autozooids; both types of avicularia present in a single colony. Ovicell globose, slightly wider than long; 0.25X 0.20 mm; smoothly calcified, perforated by about 24 small, thick-rimmed pores. Basal pore chambers and mural septula present.

Etymology

Latin, corrugatus, wrinkled, with reference to the frontal shield calcification of the zooids.

Remarks

Parkermaυella was introduced by Gordon and d’Hondt (1997) for two new species from New Caledonia, and for a suite of species from the Australian region variously attributed to Hippomenella , Schizoporella , and Schizomaυella. The morphology of Parkermaυella corrugata sp. nov. recalls those south-west Pacific species formerly attributed to the northern hemisphere genus Schizomaυella (which has an evenly perforated frontal shield, and is most similar to P. punctigera (MacGillivray) (see Gordon 1984)). It differs from that species in its larger, flatter autozooids, and broader, shallower sinus, and in possessing four rather than six, distal oral spines. The holotype colony was encrusting the bryozoan ‘‘ Myriozoum ’’ marionense Busk, 1884, while other specimens grew on shell (SAM A27500 ) or formed thick, white patches on rock (SAM A27558, A27570).

Superfamily SCHIZOPORELLOIDEA Jullien, 1883 Family BUFFONELLODIDAE Gordon and d’Hondt, 1987 Genus Ipsibuffonella Gordon and d’Hondt, 1997 Ipsibuffonella hyalina sp. nov.

( Figure 9E, F )

Material

Holotype: St. 53 Marion Island (46 ° 55 9 S, 37 ° 33 9 E), 606–775 m, SAM A27563.

Description

Colony encrusting, unilaminar. Autozooids oval to hexagonal; large, 0.88–1.0X 0.65– 0.8 mm; frontal shield convex, finely granular, imperforate, except for a few minute peripheral pores. Primary orifice wider than long, 0.24X 0.17 mm; the proximal border shallowly arcuate; a low peristomial rim developed laterally and proximally, forming a short, blunt umbo mid-proximally; oral spines absent. Avicularia absent. Ovicell prominent, globose, as wide as long, 0.67 mm; ectooecium entirely membranous, except for a very reduced area of smooth calcification proximo-laterally, on each side of the aperture; endooecium finely granular, imperforate; not closed by autozooidal operculum. Multiporous septula present.

Etymology

Greek, hyalinos, glassy, with reference to the calcification of the zooid frontal shield. Remarks

Ipsibuffonella was introduced by Gordon and d’Hondt (1997) for I. repens , recorded from 675 m on the northern Norfolk Ridge, New Caledonia. This new species resembles I. repens in its imperforate cryptocystal frontal shield, the shape of the primary orifice, and lack of spines, and in the ovicell, which in I. hyalina is almost completely composed of endooecial calcification. While the lateral walls of I. hyalina are low, they do not form the smooth slope continuous with the frontal shield, seen in I. repens , and the colony consists of a coherent sheet, without the tendency to uniserial growth seen in the latter. Avicularia have not been found in this new species, but they are present medio-proximal to the orifice in I. repens .

Figures

Figure 9. (A–D) Parkermaυella corrugata sp. nov., SAM A27559 (A, C), SAM A27558 (B, D): (A) autozooid and ovicelled autozooids, X75; (B) autozooids showing the two types of avicularia, X100; (C) detail of primary orifice and small avicularium, X150; (D) detail of primary orifice and large dimorphic avicularium, X150. (E, F) Ipsibuffonella hyalina sp. nov., SAM A27563: (E) group of autozooids, X35; (F) ovicelled autozooid, X45.