Syllis beneliahuae ( Campoy & Alquézar, 1982 )

Martín, Guillermo San, Lucas, Yolanda & Hutchings, Pat, 2023, The genus Syllis Savigny in Lamarck, 1881 (Annelida: Syllidae: Syllinae) from Australia (Part 3): new species and redescription of previously described species, Zootaxa 5230 (3), pp. 251-295 : 257-259

Syllis beneliahuae ( Campoy & Alquézar, 1982)

Figure 3

Langerhansia beneliahui Campoy & Alquézar, 1982: 124 , fig. 3a, b.—Campoy 1982: 389, pls. 39, 40.

Syllis beneliahuae .—San Martín 1984: 360, pls. 90, 91; 1992: 183, fig. 1K–M; 2003: 405, Figs 222, 223.

Syllis (Ehlersia) cerina .— Augener 1913: 209, pl. 3, fig. 40 a, textfig. 25. Non Syllis cerina Grube, 1878 .

Typosyllis (Langerhansia) cornuta .— Hartmann-Schröder 1979: 88; 1980: 52; 1981: 29.— Hutchings & Murray 1984: 104. Non Rathke, 1843.

Typosyllis beneliahuae .— Licher 1999: 47, fig. 22.

Material examined. AUSTRALIA, QUEENSLAND: Liz 52-2, Outer Yonge Reef, Great Barrier Reef , 14° 36’ S, 145° 38’ E, coll. 24 Jan 1977, hand collected coral rubble, 30 m, AM W.53779, 1 specimen . WESTERN AUSTRALIA: WA 536, Houtman Abrolhos Islands, Beacon Island, northeast entrance to Goss Passage , 28° 27’ 54” S, 113° 46’ 42” E, coll. 25 May 1994, hand collected on SCUBA underneath boulders embedded in coral sand, 33 m, AM W.53778, 1 specimen . WA 518, Houtman Abrolhos Islands, Beacon Island, Goss Passage , 28° 25’ 30” S, 113° 47’, E, coll. 22 May 1994, hand collected on SCUBA, dead coral plates covered in coralline algae, 8 m, AM W.53776, 1 specimen . WA 524, Goss Passage, south east of Long Island , 28° 28’ 48” S, 113° 46’ 30” E, coll. 22 May 1994, 30 m, hand collected in calcareous substrate, AM W.53777, 3 specimens . WA 521, Goss Passage, north end of Long Island , 28° 28’ 18” S, 113° 46’ 18” E, coll. 22 May 1994, 8 m, hand collected dead coral covered in coralline algae, AM W.53775, 4 specimens . Site 70, Kimberley region, Descartes Island , 14° 11’ S, 125° 40’ E, coll. 20 July 1988, P. Hutchings, intertidal sand flats and mangroves, AM W.29542, several specimens. St. 115, Kimberley region, Shirley Island , St. 115, 16° 17’ S, 123° 26’ E, coll. 26 July 1988, coll. P. Hutchings, intertidal, in mangroves, sand and reef, AM W.29544, 1 specimen .

Diagnosis. Body slender. Midbody dorsal cirri moderately long, alternating long and short; antennae tentacular and anterior dorsal cirri markedly longer. Compound chaetae of two kinds, few dorsal ones with bidentate spinigerlike blades and remaining chaetae with distinctly shorter, finely bidentate blades. Posterior aciculae acuminate.

Description. Complete specimens, 8–9 mm long, 0.2 mm wide, with 81–91 chaetigers. Body relatively small, slender, filiform, without colour pattern. Prostomium rounded; four small eyes in trapezoidal arrangement. Palps elongated, longer than prostomium ( Fig. 3A ). Median antenna arising between posterior eyes, with about 16–22 articles, almost twice as long as combined length of prostomium and palps together; lateral antennae shorter than median one, with about 13–15 articles. Peristomium dorsally markedly shorter than subsequent segments ( Fig. 3A ). Dorsal tentacular cirri longer than lateral antennae and similar in length or shorter than median antenna, with about 18–20 articles; ventral tentacular cirri about half of length of dorsal ones, with 10–12 articles. Dorsal parapodial cirri of chaetigers 1 and 4 distinctly long, with about 25–27 articles, those of chaetiger 2 and 3 shorter, with 14–15 articles, remaining dorsal cirri alternating long and short; in midbody, long ones with about 20–22 articles, longer than body width; short ones with 10–11 articles, shorter than body width ( Fig. 3B ); articles of dorsal cirri with distinct, spiralized inclusions inside, especially from proventricular segments onwards ( Fig. 3A, B ). Parapodia conical. Ventral parapodial cirri digitiform, slightly longer than parapodial lobes. Compound chaetae of each parapodium with pseudospinigers and falcigers; one (sometimes two on most anterior parapodia) dorsalmost chaetae provided with distinctly longer and slender blades, pseudospinigers, distally bidentate, proximal tooth smaller than distal one, and straight, moderate spines on margins ( Fig. 3C, E, G ), 38 μm on anterior parapodia ( Fig. 3C ), 60 µm on midbody ( Fig. 3E ) and longer from midbody onwards, 80 μm long ( Fig. 3G ). Falcigers short, bidentate, proximal tooth shorter than distal one, and moderately long, straight spines on margin ( Fig. 3D, F, H ); anterior parapodia with 6–8 falcigers, 20–12 µm long ( Fig. 3D ); midbody and posterior parapodia each with four falcigers, with longer spines on margin, slightly distally curved on most dorsal ones, of similar length than those of anterior parapodia ( Fig. 3F, H ). Dorsal simple chaetae only seen in last parapodia of some specimens, minute, distally pointed and finely bidentate. Ventral simple chaetae only on most posterior segments of some specimens, similar to dorsal ones, smooth.Anterior parapodia with three slender aciculae each, distally pointed ( Fig. 3I ), reducing to two in each midbody parapodia, one acuminate and the other straight ( Fig. 3J ); solitary on posterior parapodia, acuminate ( Fig. 3K ). Pharynx long, extending through about 8–9 segments; pharyngeal tooth conical, on anterior margin of pharynx ( Fig. 3A ), usually located on chaetiger 3. Proventricle slightly shorter than pharynx, through 4–5 segments, with about 33–35 muscle cell rows. Pygidium with two anal cirri, and a median stylus.

Remarks. Licher (1999) pointed that the Australian specimens reported as Syllis (Ehlersia) cerina by Augener (1913), Typosyllis (Langerhansia) cornuta by Hartmann-Schröder (1979, 1980, 1981) and Langerhansia cornuta by Hutchings & Murray (1984);are all similar but differ from the original description of Syllis cerina ; the pseudospinigers are longer and unidentate in S. cerina from the Philippines, the falcigers have a smaller proximal tooth and shorter spines on their margin. We have followed Licher (1999) in our list of synonymies.

Syllis cornuta Rathke, 1843 , from Northern Europe, has longer dorsal cirri, straight acicula in posterior parapodia, and the falcigers are more elongated, with shorter spines on margin than those of S. beneliahuae (see Licher 1999).

Habitat. Dead coral, vermetid reefs, calcareous algae, among mussels, coralline algae, sand. Intertidal to more than 30 m.

Distribution. Mediterranean, East Atlantic (Canary Islands), West Atlantic (Caribbean Sea, Cuba), Pacific coast of Panamá. New record for Australia (NSW, WA, QLD). This widespread distribution should be confirmed by molecular studies, as may represent a suite of cryptic species.

Figures

FIGURE 3. Syllis beneliahuae (Campoy & Alquézar, 1982). AM W.29542. A, anterior end, dorsal view. B, long and short dorsal cirri, midbody. C, pseudospiniger, most anterior parapodia. D, falcigers, most anterior parapodia. E, pseudospiniger, midbody. F, falcigers, midbody. G, pseudospiniger, mid-posterior parapodia. H, falcigers, mid-posterior parapodia. I, aciculae, anterior parapodia. J, aciculae, midbody. K, acicula, posterior parapodium. Scale. A, B: 0.2 mm. C–K: 20 µm.