Pseudofabriciola Fitzhugh, 1990b

Fitzhugh, K., 2002, New species of Fabricinuda Fitzhugh and Pseudofabriciola Fitzhugh (Polychaeta: Sabellidae: Fabriciinae), with an emendation of Pseudofabriciola australiensis (Hartmann-SchroÈder), Journal of Natural History 36 (8), pp. 893-925 : 900-903

Pseudofabriciola Fitzhugh, 1990b

Pseudofabriciol a australiensis (Hartmann-Schr oÈder, 1981), emended (®gure 3; tables 4, 6) Fabriciola australiensis Hartmann-SchroÈder, 1981: 60±61, ®gures 138±145; 1984: 47; 1985: 89. Pseudofabriciola australiensis (Hartmann-SchroÈder, 1981). Fitzhugh, 1990b: 2 ±3.

Material examined. Indian Ocean, Western Australia, Shark Bay , Denham. One specimen ( GWR), sta. 96, 200±300 m oOE Denham beach, south of jetty, scrapings of Laurencia from various bivalve shells on sandy bottom, depth less than 2 m, 17 April 1995, coll. G. W. Rouse.

Additions to description. Specimen a complete, sexually mature female with eight thoracic and three abdominal setigers. Branchial crown length 1.30 mm, remainder of body 1.70 mm long, maximum width 0.20 mm. Body slender, slightly tapering anteriorly and posteriorly. Branchial crown with three pairs of radioles, distal ends ®lamentous, same width as pinnules. Radioles each with nine pairs of pinnules, all terminating at about same height as ends of radioles. Dorsal lips erect, distally rounded, distinct from dorsalmost radioles (®gure 3). Low, distally rounded, ventral lip-like process present at base of proximalmost pinnule of ventralmost radioles. Branchial hearts present. Vascularized, ventral ®lamentous appendage s present; surfaces with minute wrinkles; about one-third length of radioles and about two times wider than pinnules; narrow blood vessel originating from branchial heart extends through most of ®lament length. Dorsal margins of branchial lobes not fused to one another; lobes narrow proximally, each terminating as short, peduncle-like stalk. Ventral ®lamentous appendages light golden brown, remainder of crown lacking pigmentation; posterior peristomial ring and setigers 1±4 with diOEuse, light brown pigmentation over body surface. Oocytes present in setiger 4. Tube absent. No brooding of young.

Remarks. In his redescription of the species, Fitzhugh (1990b) noted that the type series for Pseudofabriciola australiensis only consists of the holotype and three paratypes, all of which lack a branchial crown. The present specimen is the ®rst complete one of this species. It largely conforms to the original description of P. australiensis provided by Hartmann-SchroÈder (1981) and the redescription by Fitzhugh (1990b). The type specimens and the present specimen have an identical collar form, with a pair of dorsolateral, V-shaped notches and a mid-dorsal U-shape d notch on the collar margin, as well as the main fang of thoracic uncini having a swollen appearance (cf. Fitzhugh, 1990b: ®gure 3C). The most notable diOEerence is that the type specimens do not have body wall pigmentation, whereas the present specimen has light brown pigmentation in the anterior thorax. Without additional specimens on which to judge pigment variability, I am not certain whether this feature denotes separate species or just regional variation. The type locality is Horrocks, Western Australia, which is about 300 km south of the location where the complete specimen was collected. The present specimen of P. australiensis occurs in the same locality as P. rousei n. sp., described below.

The presence of well-developed dorsal lips and vascularized, ventral ®lamentous appendages in Pseudofabriciola australiensis con®rms the prediction by Fitzhugh (1990b: 3, see also Fitzhugh and Simboura, 1995: 9 ±10) that these features would

1. Dorsal lips: (0) well-developed, triangular lobe; (1) low, narrow ridge.

2. Ventral margins of branchial lobes: (0) as vascularized, ventral ®lamentous appendages; (1) as narrow shelf-like processes.

3. Mid-dorsal surface of collars that are entire mid-dorsally: (0) smooth; (2) longitudinally grooved.

4. Mid-dorsal collar margin: (0) entire; (2) notched or incised.

5. Dorsolateral collar margins: (0) entire; (1) notched or incised.

6. Thoracic uncini main fang: (0) slender; (1) swollen.

7. Thoracic uncini dentition: (0) series of subequal teeth above main fang; (1) large tooth above main fang.

8. Abdominal uncini manubrium: (0) same length as dentate region; (1) 1.5 times longer than dentate region; (2) two times longer than dentate region.

be found in this species. This prediction was based on the overall similarities of P. australiensis to P. incisura Fitzhugh, 1990b . It was on the basis of this prediction that Fitzhugh (1991a, 1991b, 1992) considered P. australiensis to have well-developed dorsal lips and ventral ®lamentous appendages for the purposes of determining cladistic relationships within the genus and between Fabriciinae genera. As well, Fitzhugh et al. (1994) and Fitzhugh and Simboura (1995) investigated possible cladistic relationships among Pseudofabriciola species based on diOEerent combinations of states for dorsal lips and ®lamentous appendages in P. australiensis . The relationship of P. australiensis to other species in the genus is presented in the cladistic analysis below.

On the basis of general similarities ( table 4), Pseudofabriciola australiensis is most similar to P. incisura and P. quasiincisura Fitzhugh, 1996 . These are the only species in the genus with ventral ®lamentous appendages (e.g. ®gure 3), and the margin of the collar has a mid-dorsal U-shaped notch and a pair of dorsolateral V-shaped notches.