Syllis warrnamboolensis ( Hartmann-Schröder, 1987 ) Hartmann-Schroder, 1987

Martín, Guillermo San, Álvarez-Campos, Patricia & Hutchings, Pat, 2017, The genus Syllis Savigny in Lamarck, 1818 (Annelida: Syllidae: Syllinae) from Australia (second part): four new species and re-description of twelve previously described species, Zootaxa 4237 (2), pp. 201-243 : 235-238

Syllis warrnamboolensis ( Hartmann-Schröder, 1987) , n. comb.

Figures 21 , 22

Typosyllis (Typosyllis) warrnamboolensis Hartmann-Schröder, 1987: 35 , figs 7‒9; 1989: 21. Typosyllis warrnamboolensis . Licher 1999: 108, fig. 50.

Typosyllis (Typosyllis) geelongensis Hartmann-Schröder 1987: 36 , figs 10‒12; 1989: 20; 1990: 46. Typosyllis (Typosyllis) riseri Hartmann-Schröder, 1989: 22 , figs 24‒27; 1990: 48; 1991: 29.

Material examined. AUSTRALIA. NEW SOUTH WALES. South Head , Lake Macquarie, among algae, 15 January 1976, coll. and id. Hartmann-Schröder , 2 specimens as Typosyllis (Typosyllis) warrnamboolensis , HZM P– 20025. QUEENSLAND: Lizard Island , Creefs Lizard Island Expedition , 2010: Watson Bay, 14° 39' 26" S, 145° 27' 03" E AM W.41722 , 4 specimens, one mounted for SEM AM W.42419.001, coll. coral rubble, 4.5 m, 28 August, 2010; High Rock , 14° 49' 34" S, 145° 33' 08" E, AM W.41704 , 4 specimens, coll. coral rubble, 20.1 m, 11 September 2010. WESTERN AUSTRALIA: Woodside Kimberley Survey , 2009, 15° 56' 40" S, 124° 16' 00" E, AM W.42535 , 3 specimens, intertidal, 22 October, 2009; Adele Island, sublittoral fore-reef slope, 15° 34' 48" S, 123° 9' 26" E, AM W.42537; 1 specimen, coll. 7.5 m, 18 October 2009 ; Montgomery Reef , 15° 52' 35" S, 124° 19' 48" E, AM W.42536, 1 specimen, coll. mid-littoral fore-reef ramp, intertidal, 20 October, 2009.

Comparative material. Typosyllis (Typosyllis) geelongensis Port Lonsdale (South Australia), 24 December 1975, coll. and leg. G. Hartmann-Schröder, 2 Paratypes ( HZM P-18862).

Typosyllis (Typosyllis) riseri . Southheads Lake Macquarie , 15 January 1976, coll. and leg. Hartmann- Schröder, 1 Paratype ( HZM P-19660).

Description. Body elongated, relatively slender, delicate. Largest complete examined specimen 13.5 mm long, 0.1 mm wide, with 92 chaetigers. A thin orange transversal line on anterior part of anterior segments ( Figs 21 A, 22 A, B). Prostomium oval, wider than long, with two pairs of red-orange eyes in trapezoidal arrangement ( Figs 21 A, 22A, B). Median antenna inserted on middle of prostomium, between anterior pair of eyes, longer than combined length of prostomium and palps, with 33–35 articles ( Figs 21 A, 22A); lateral antennae shorter, inserted on anterior margin of prostomium, with 18–20 articles ( Figs 21 A, 22A, B). Palps triangular, longer than prostomium ( Figs 21 A, 22 A, B). Nuchal organs not seen. Peristomium similar in length to subsequent segments ( Figs 21 A, 22B). Dorsal tentacular cirri slightly shorter than median antenna, with 25–28 articles; ventral ones shorter, with 14–16 articles ( Figs 21 A, 22B). Dorsal parapodial cirri relatively slender, elongate, anterior ones with 25‒30 articles, midbody to posterior ones with 18‒22 articles, alternating long and short cirri ( Fig. 21 A); dark inclusions inside articles. Anterior and midbody parapodia each with 8 to 10 compound chaetae each, reducing progressively to 5 chaetae on each posterior parapodium. Blades bidentate, both teeth similar, and short spines on margin; dorsoventral gradation in length, 22 µm long above, 10 µm long below on anterior parapodia; 20‒8 µm long on midbody and posterior parapodia) ( Figs 21 B-D, 22E‒F, H). Dorsal simple chaetae on posterior parapodia only, distally bifid, with short subdistal spines ( Figs 21 E, 22H); ventral simple chaetae on posterior parapodia only, gently bidentate, with few subdistal spines, slightly curved ( Figs 21 F, 22G, H). Three straight aciculae in each anterior parapodium, sometimes 4, one distally curved ( Fig. 21 G). Single acicula in each midbody and posterior parapodium, almost straight, slightly curved distally ( Fig. 21 H, I), tip protruding from parapodial lobe. Pharynx longer than proventricle, extending through 12 segments; conical tooth located on anterior margin. Proventricle through 5 segments with about 38 muscle cell rows ( Fig. 21 A). Pygidium small, with 2 anal cirri with about 20 articles each and a short median stylus. One specimen with a developing Dicerous stolon, with 10 chaetigers ( Fig. 22 C).

Remarks. The specimens agree well with the description of Typosyllis warrnamboolensis of Licher (1999), except in details of the aciculae. S. warramboolensis is a species difficult to identify, since it lacks distinctive characters, except for the colour pattern, which is not very conspicuous and easily lost after fixation. The most similar species are S. variegata Grube, 1860 and S. westheidei San Martín, 1984 . All these three species have similar chaetae, but they have different colour pattern, and the shape of the aciculae. In S. variegata the colour pattern is composed by transversal and strongly marked figures of 8; similar colour pattern is present in S. westheidei , but much less marked, and thin transverse lines on each anterior segment in S. warrnamboolensis . The posterior aciculae are totally straight, thick, distinctly protruding from parapodial lobes in S. variegata , and more acuminate, not protruding in the S. westheidei and S. warrnamboolensis , which also have smaller proximal tooth in the compound chaetae (see San Martín, 2003). This is the first description of the stolon of S. warrnamboolensis .

Habitat. Coral rubble, algae.

Distribution. Australia (Victoria, New South Wales, Queensland, Tasmania, South Australia).

Figures

FIGURE 21. Syllis warrnamboolensis (Hartmann-Schröder, 1987), n. comb. (AM W. 41722). A, anterior end, dorsal view. B, compound chaetae, anterior parapodium. C, compound chaetae, midbody parapodium. D, compound chaetae, posterior parapodium. E, dorsal simple chaeta. F, ventral simple chaeta. G, aciculae, anterior parapodium. H, acicula, midbody. I, acicula, posterior parapodium. Scale bars: A, 0.1 mm. B ‒ I: 20 µm.

FIGURE 22. Syllis warrnamboolensis (Hartmann-Schröder, 1987), n. comb. (AM W. 42419). A, anterior end, dorsal view. B, prostomium. C, dicerous stolon, dorsal view. Scanning Electron Micrographs: D, anterior end, dorsal view. E, compound chaetae, anterior parapodium. F, compound chaetae, midbody parapodium. G, ventral simple chaetae, posterior parapodium. H, compound chaetae and dorsal simple chaetae, posterior parapodium.