Sabellariidae from Lizard Island, Great Barrier Reef, including a new species of Lygdamis and notes on external morphology of the median organ Author Capa, María Author Faroni-Perez, Larisse Author Hutchings, Pat text Zootaxa 2015 4019 1 184 206 journal article 10.11646/zootaxa.4019.1.10 52ee815e-9e7e-40c3-b900-e0e03f07c8ae 1175-5326 245139 28811FA6-340B-42AE-9D3A-12BA3BFC7EF6 Sabellaria lungalla Hutchings, Capa & Peart, 2012 Sabellaria lungalla Hutchings et al. 2012: 44 –46. Material examined. AM W.47552, MI QLD 2194, Lizard Island, Watson’s Bay, 14°39'41"S , 145°22'27"E , in amongst Halimeda on coral rubble, 4.6 m, 28 Aug 2010 . Comparative material examined. Holotype of Sabellaria lungalla Hutchings, Capa & Peart, 2012 , NTM W16893, Northern Territory, McArthur River, 15°23'S , 136°30'E , 17 Mar 1993 . Paratypes : NTM W16896, Drimmie Arm, Melville Bay, Gove, 12°14'S , 136°42'E ; NTM W10043, Darwin Harbour, 12°29'31"S , 130°50'10"E , 7 m , 14 Jul 1993 . Remarks. The single well preserved specimen collected lacked pigmentation at the base of the opercular lobes (unlike the types ). The morphological traits observed in the specimen mostly match the description of the species (Hutchings et al . 2012). The median ridge, pigmented at its proximal end, is thin and elongated, with a free terminal portion, the median organ, extending to base of the paleae. Sabellaria lungalla is characterised by the morphology of the paleae, bearing outer paleae with serrated distal margin, a midline plume, a single type of middle paleae, geniculate and with smooth pointed tips, and asymmetrical inner paleae with short blunt tips, two pairs of nuchal spines and one pair of lateral lobes on segment 2. The specimen from Lizard Island reported herein bears middle paleae with notable longer distal tips than those described previously (Hutchings et al. 2012), similar to the intraspecific variation observed in other congeners ( Lezzi et al. 2015 ). This new record expands its known distribution range within tropical Australia . Habitat. Intertidal in sheltered bays from intertidal to 15 m , often associated with Halimeda beds. Distribution. Tropical Australia (Northern Territory, north Western Australia and northern Queensland).