Nooralia bulgannabooyanga San Martín, 2002

Guillermo San Martin, 2005, Exogoninae (Polychaeta: Syllidae) from Australia With the Description of a New Genus and Twenty-two New Species, Records of the Australian Museum 57, pp. 39-152 : 46-48

Nooralia bulgannabooyanga San Martín, 2002

Figs. 1A–D, 2A–G, 3A–F

Nooralia bulgannabooyanga San Martín, 2002: 336, figs. 1–3.

Material examined. AUSTRALIA: NEW SOUTH WALES. HOLOTYPE: 1 specimen, AM W26326, Barrenjoey Head, Broken Bay, 33°35'S 151°20'E, algae on rocky substrate, 5 m, J.K. Lowry, R.T., et al., 22 Apr 1993. Paratype: specimen on SEM stub, AM W27400, Barrenjoey Head, Broken Bay, 33°35'S 151°20'E, algae on rocky substrate, 5 m, J.K. Lowry, R.T., et al., 22 Apr 1993. Paratype: 1 specimen, AM W27399, Barrenjoey Head, Broken Bay, 33°35'S 151°20'E, algae on rocky substrate, 5 m, J.K. Lowry, R.T., et al., 22 Apr 1993. Paratype: 1 specimen,AM W26342, Halfway Reef, 200 m south of Sullivan Reef, Ulladulla, 35°21.42'S 150°29.31'E, airlift over wall of sponges, bryozoa & hydrozoa, 15 m, K. Attwood, et al., 3 May 1997. 1 specimen, AM W28414, Northwest corner of Bowen Island, Jervis Bay, 35°06.8'S 150°46.11'E, dense bryozoans under rock ledge, 13 m, P. Serov & G.D.F. Wilson, 8 Dec 1993. 5 specimens, AM W28405, South ledge, Cook Island, 28°11.65'S 153°34.63'E, rock, 15 m, K.Attwood, 9 Jun 1993. WESTERN AUSTRALIA. 1 specimen. AM W ex 28366, Red Bluff, Kalbarri, 27°42'S 114°9'E, round-leaved seagrass in shallow sand on rocky shore, 3.5 m, R.T. Springthorpe, 10 Jan 1984.

Description. Body small, short, holotype 2.4 mm long, 0.3 mm wide, 31 chaetigers. Prostomium quadrangular to trapezoidal; 4 eyes in trapezoidal arrangement, apparently without anterior eyespots (Fig. 1A,B). Antennae missing on holotype and one paratype; another paratype with lateral antennae but median antenna missing; lateral antennae inserted just in front of anterior eyes, cylindrical, slightly rugose, longer than combined length of prostomium and palps (Fig. 1B); median antenna inserted at same level than lateral antennae, about twice as long. Palps fused at bases (Fig. 1A,B), usually ventrally folded (Fig. 2A). Dorsal tentacular cirri long and thick, laterally directed, similar to lateral antennae but longer, distinctly longer than body width (Fig. 1A,B); ventral tentacular cirri slightly shorter than half length of dorsal tentacular cirri, oblique to laterally directed (Fig. 1A,B). Dorsal cirri of chaetiger 1 long, anteriorly directed, similar to dorsal tentacular cirri. Dorsal cirri present on all parapodia; dorsal cirri of chaetiger 2 much shorter than those of chaetiger 1, similar in length to ventral tentacular cirri, but distinctly longer than remaining dorsal cirri (Fig. 1A,B); dorsal cirri of midbody lanceolate, shorter than half body width, longer than parapodial lobes, slight variation in length (Fig. 1C). Last 2–3 segments with small dorsal cirri but lacking parapodia and chaetae (Fig. 1D). Ventral cirri large, ovate, slightly laminar (Fig. 2A). Parapodial lobes conical, distally bilobed and provided with posterior papilla (Fig. 2A). Parapodia of chaetiger 1 with 1 compound bidentate chaeta, the dorsalmost one, and 6 compound chaetae with unidentate, smooth, curved blades (Fig. 2B); progressively increasing numbers of compound chaetae with bidentate blades, chaetae with only bidentate blades from chaetiger 3–4. Midbody parapodia each with about 8–9 compound chaetae, strongly heterogomph, with spinose to rough shafts, and short, bidentate blades with short, fine marginal spines, inverse dorsoventral gradation in length, about 7–8 µm dorsally, 10 µm ventrally (Figs. 2D, 3E,F); posterior parapodia each with 9 compound chaetae, similar to those of midbody, with greater differences between dorsal and ventral blades (Fig. 2F). Dorsal simple chaetae from chaetiger 1, thin, distally with short, fine marginal spines, similar throughout (Fig. 2C,E). Ventral simple chaetae absent. Acicula solitary, slender, distally rounded, with a short, rounded tip (Fig. 2G). Pharynx long, slender, indistinct, everted or partially everted on all specimens, without pharyngeal tooth, a dark glandular area near proventricle (Fig. 1A,B), a crown of 10 soft papillae on anterior rim and few other, small and rounded, near distal crown. Proventricle small, minute, difficult to see, through 1–2 segments (Fig. 1A,B). Pygidium semicircular, with 2 long, wide, anal cirri (bifid on 1 paratype) (Fig. 1D). Females carrying eggs dorsally (Fig. 3A) by means of compound notochaetae (Fig. 3B–D).

Remarks. This genus and species is unique in the family Syllidae, in having the combination of a minute proventricle, unarmed pharynx, palps separated except basally, antennae, tentacular cirri and dorsal cirri of chaetiger 1 long, distally tapered, and remaining dorsal cirri short, spindle-shaped to oval, and, especially, because mature females brooding by means of compound notochaetae. Strictly, this taxon does not belong to any of the known subfamilies of the Syllidae; Nooralia, however, is placed provisionally in the Exogoninae because of its small, short body, presence of ventral cirri, short dorsal cirri on midbody, and brooding of eggs.

Distribution. Australia (New South Wales, Western Australia).

Habitat. Amongst algae, bryozoans and hydrozoans; 3.5– 15 m depth.