Syllides tam, San Martin & Hutchings, 2006

San Martin, G & Hutchings, PA, 2006, Eusyllinae (Polychaeta: Syllidae) from Australia with the Description of a New Genus and Fifteen New Species, Records of the Australian Museum 58, pp. 257-370 : 363-365

Syllides tam n.sp.

Figs 86A,B, 90A–G

Syllides longocirrata .— Augener, 1913: 229.— Haswell, 1920: 102.—Hutchings & Murray, 1984: 33. Not Örsted, 1845: 11.

Material examined. HOLOTYPE ( AM W28472) AUSTRALIA: NEW SOUTH WALES: 1.5 km SE of Dangar Is., Hawkesbury R., 33°33'S 151°14'E, sandy mud, 7 m, coll. Jones & party, 21 Aug 1980 . PARATYPES. 50 m NE of Green Point, Hawkesbury R., 33°33.5'S 151°14.5'E, sandy mud, 4 m, coll. A.R. Jones & party, 17 May 1982, 1 ( AM W24704) ; 300 m NE of Green Point, Hawkesbury R., 33°34'S 151°13.5'E, sandy mud, 5 m, coll. A.R. Jones & A. Murray, 18 Nov 1980, 1 ( AM W28463) ; 1 km S of E end, Spectacle Is. , Hawkesbury R., 33°32'S 151°07.5'E, muddy sand, 12 m, coll. A.R. Jones & A. Murray, 5 Aug 1983, 1 ( AM W28464) ; 1 km S of E end, Spectacle Is. , Hawkesbury R., 33°32'S 151°07.5'E, muddy sand, 12 m, coll. A.R.Jones & A.Murray, 11 Nov 1983, 1 ( AM W28465) ; 1 km SE of Dangar Is., Hawkesbury R., 33°33'S 151°14'E, shelly mud, 9 m, coll. A.R. Jones & party, 1 Aug 1979, 1 ( AM W28466) ; 1 km SE of Dangar Is., Hawkesbury R., 33°33'S 151°14'E, shelly mud, 9 m, coll. A.R. Jones & party, 21 Aug 1980, 1 ( USNM 1082992 ) ; 30 m SE of Brooklyn boat-channel, Hawkesbury R., 33°33'S 151°14'E, shelly mud, 7 m, coll. A.R. Jones & party, 18 Dec 1979, 1 ( LACM ex AM W28469) ; 30 m SE of Brooklyn boat-channel, Hawkesbury R., 33°33'S 151°14'E, shelly mud, 7 m, coll. A.R. Jones & party, 1 Aug 1979, 1 ( AM W28470) ; 1.5 km SE of Dangar Is., Hawkesbury R., 33°33'S 151°14'E, sandy mud, 7 m, coll. A.R. Jones & party, 1 Aug 1979, 3 ( AM W28471) ; 1.5 km SE of Dangar Is., Hawkesbury R., 33°33'S 151°14'E, sandy mud, 7 m, coll. A.R. Jones & party, 18 Dec 1979, 1 ( AM W28473) ; Brooklyn boat-channel, Hawkesbury R., 33°33'S 151°14'E, fine mud, 3 m, coll. A.R.Jones, 16 May 1980, 1 ( AM W28474) ; Midway between Green Point and Croppy Point, Hawkesbury R., 33°33.5'S 151°14.5'E, mud, 6 m, coll. A.Jones & party, 22 Nov 1980, 1 ( AM W196517 ) ; E end Brooklyn boat channel, 1 ( AM W196518 ) ; Liverpool Reach , Hawkesbury R., 33°25'S 150°56'E, fine sand, 4 m, coll. A. Jones & party, 21 Feb 1980, 1 ( AM W196657 ) ; Liverpool Reach , Hawkesbury R., 33°25'S 150°56'E, coarse sand, 20 m, coll. A.Jones & party, 21 Feb 1980, 3 ( AM W196658 ) ; Liverpool Reach , Hawkesbury R., 33°25'S 150°56'E, coarse sand, 20 m, coll. A. Jones & party, 21 Feb 1980, 21 ( AM W196659 ) .

Additional material examined. QUEENSLAND: At mouth of Althaus Creek, Halifax Bay, 19°10'S 146°36'E, 2 m, coll. Queensland Nickel, Jan 1977, 2 ( AM W28207) . NEW SOUTH WALES: 0.5 km E. of Dangar Is ., Hawkesbury R., 33°33'S 150°14'E, coll. A. Jones & party, 21 Aug 1980, 4 on SEM stub ( AM W196520 ) ; S of airport runway extension, Botany Bay , 33°58.13'S 151°11.16'E, 5 m, coll. Australian Museum party, 7 Apr 1992, 1 ( AM W21631) ; SW of airport runway extension, Botany Bay , 33°58.33'S 151°10.22'E, 7 m, coll. Australian Museum party, 28 July 1992, 1 ( AM W21632) ; E of Marley , 34°08.08'S 151°09.65'E, sand, 60 m, coll. Fisheries Research Institute (NSW), 2 May 1991, 1 ( AM W24377) ; Bass Point , 34°36'S 150°54'E, 50 m, coll. The Ecology Lab for RMI / Pioneer Project, 1 Feb 1990, few ( AM W22994) ; Montagu Roadstead , Jervis Bay, 35°02.2'S 150°46'E, 12 m, coll. P.A. Hutchings & party, 6 Jun 1991, 1 ( AM W27574) . VICTORIA: Port Phillip Bay , 38°09.3'S 144°42.7'E, sand, 3 m, coll. Marine Pollution Studies Group, 11 Jun 1971, 2 ( AM W16236) .

Description. Body about 2.4 mm long, 0.2 mm wide, with 30 chaetigers. Prostomium oval, slightly wider than long; 4 eyes arranged in open trapezoidal pattern and 2 anterior eyespots; median antenna inserted between posterior eyes, about one and half times combined length of prostomium and palps, lateral antennae about two thirds of length of median antenna, inserted near anterior eyes ( Fig. 90A). Palps similar in length to prostomium, without distal papillae. Peristomium slightly shorter than subsequent segments, with hyaline, rounded inclusions; dorsal tentacular cirri similar to median antenna, slightly shorter; ventral tentacular cirri about two thirds length of dorsal ones ( Fig. 90A). Antennae, tentacular, and dorsal cirri of chaetigers 1 and 2, elongate, slender; dorsal cirri of chaetiger 1 longer than median antenna, those of chaetiger 2 shorter than those of chaetiger 1, similar in length to median antenna. Dorsal cirri of subsequent segments alternating irregularly with long cirri, distinctly longer than body width, with about 10–12 articles; short cirri, similar in length to body width, with about 6–7 articles; articles pyriform, usually with 1 dark inclusion ( Fig. 90A). Parapodial lobes elongated, conical, distally bilobed ( Fig. 90C). Ventral cirri digitiform, similar in length to parapodial lobes. Compound chaetae similar throughout, shafts with several, long, fine, subdistal spines, and elongated, bidentate blades, within fascicle 5 pairs of chaetae, each pair similar in shape and length ( Fig. 90D– G). Blades of most dorsal pair of compound chaetae with single long, distinct basal spur, and moderate, thin spines on margin, about 60–62 µm long; blades of second pair similar to those of most dorsal pair, but shorter, about 52 µm long, with shorter spines on margin ( Figs 90D, 86A). Blades of subsequent pairs without basal spur and having short spines on margin ( Fig. 90E–G), 40, 27 and 15 µm in length respectively. Dorsal simple chaetae from chaetiger 1, unidentate, distally blunt, provided with distal hood and short spines on margin (under light microscope) ( Fig. 90H); under SEM, hood consists of several rows of minute spines ( Fig. 86B). Ventral simple chaetae absent. Acicula solitary, distally knobbed ( Fig. 90I). Pharynx through 5–6 segments ( Fig. 83A). Proventricle barrel-shaped, through about 5–6 segments, with 35 muscle cell rows. Pygidium small, semicircular, with 2 short, smooth lateral anal cirri and 1 median, longer cirrus ( Fig. 90B).

Remarks. This species has been reported in Australia as Syllides longocirrata ( Örsted, 1845) , which only occurs in the Northern Atlantic and Northern Pacific areas, and differs from the Australian specimens, which are described as a new species. Syllides longocirrata has dorsal simple chaetae that are pointed and without a hood, and the compound chaetae are unidentate (see Banse, 1972), whereas the compound chaetae of Syllides tam are distally blunt and hooded. Syllides japonicus Imajima, 1966 (see below) and S. floridanus Perkins, 1981 , also have dorsal simple chaetae that are pointed, and without a hood ( Perkins, 1981), which differ from those present in Syllides tam .

Habitat. Occurring in coarse, medium to muddy sand; from intertidal to 60 m.

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

Etymology. The species is named after The Australian Museum.