Syllidae | |
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Syllis gracilis micrograph, showing the distinctive barrel-shaped proventricle | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Annelida |
Clade: | Pleistoannelida |
Subclass: | Errantia |
Order: | Phyllodocida |
Suborder: | Nereidiformia |
Family: | Syllidae Grube 1850 [1] |
Synonyms | |
Levidoridae |
Syllidae, commonly known as the necklace worms, [2] is a family of small to medium-sized polychaete worms. Syllids are distinguished from other polychaetes by the presence of a muscular region of the anterior digestive tract known as the proventricle. [3] [4]
Syllid worms range in size from 2–3 mm (0.08–0.12 in) to 14 centimetres (5.5 in). Most syllids are benthic organisms that transition to a pelagic epitoke for reproduction. They are found in all regions of the ocean, from the intertidal zone to the deep sea, and are especially abundant in shallow water. [3] [5]
They are found in a range of habitats, moving actively on rock and sandy substrates, hiding in crevices and among seaweeds, and climbing on sponges, corals, hydrozoans, seagrasses and mangroves. They are generalist feeders. [6] A young Syllid was one of the first worms to be found with pollen from seagrass in its stomach, making it a possible pollinator. [7]
The proventricle, Syllid worm's most distinctive anatomical feature, allows the worm to feed by sucking due to its pumping action. It also plays a role in hormone production, and thus the worm's sexual development. [4] The proventricle is composed of strirated muscle cells with the longest known sacromeres among animals. [8] The proventricle is usually visible through the body wall. [9]
Syllis ramosa was the first polychaete discovered to have a branching body plan. [10] Later, two species of Ramisyllis were discovered to have a branching body plan.
The genus Glycera is a group of polychaetes commonly known as bloodworms. They are typically found on the bottom of shallow marine waters, and some species can grow up to 35 cm (14 in) in length.
Nereis is a genus of polychaete worms in the family Nereididae. It comprises many species, most of which are marine. Nereis possess setae and parapodia for locomotion and gas exchange. They may have two types of setae, which are found on the parapodia. Acicular setae provide support. Locomotor setae are for crawling, and are the bristles that are visible on the exterior of the Polychaeta. They are cylindrical in shape, found not only in sandy areas, and they are adapted to burrow. They often cling to seagrass (posidonia) or other grass on rocks and sometimes gather in large groups.
Salvatoria is a genus of polychaetes belonging to the family Syllidae.
Nephtys is a genus of marine catworms. Some species are halotolerant to a degree in that they can survive in estuaries and estuarine lagoons down to a salinity of 20 psu.
Harmothoe is a genus of marine Polychaete worms belonging to the family Polynoidae. Species of Harmothoe are found world-wide to depths of at least 5,000 m but are more common in shallower water.
Ampharetinae are a subfamily of terebellid "bristle worm". They are the largest subfamily of the Ampharetidae, of which they contain the great majority of the described genera.
Phyllodoce is a genus of polychaete worms, which contains about 200 species. The prostomium bears eyes, two pairs of antennae and a pair of large retractile nuchal organs. The eversible proboscis is clearly divided into two parts.
Amphinomidae, also known as the bristle worms or sea mice, are a family of marine polychaetes, many species of which bear chaetae mineralized with carbonate. The best-known amphinomids are the fireworms, which can cause great pain if their toxin-coated chaetae are touched or trodden on. Their relationship to other polychaete groups is somewhat poorly resolved.
Salvatoria pilkena is a species belonging to the phylum Annelida, a group known as the segmented worms. The species name comes from an Aboriginal word, pilkena, meaning "different", due to its characteristic features. Salvatoria pilkena belongs to a reduced group of species that possess rugose dorsal cirri, contrary to the typical spindle-shaped cirri found in its genus. It also lacks dorsal cirri on chaetiger 2. It resembles Salvatoria swedmarki and S. celiae, differing from pilkena in that the latter has significantly longer proventricles, while its compound chaetae are short and unidentate. At the same time, S. opisthodentata has a similar body and compound chaetae but appears to possess dorsal cirri on its chaetiger 2.
Erinaceusyllis hartmannschroederae is a species belonging to the phylum Annelida, a group known as the segmented worms. This species was previously described in Australia as Sphaerosyllis erinaceus and S. erinaceus erinaceus, a species distributed throughout the globe. These species appear to be a species complex. Previous descriptions stated that the two aforementioned species possess compound chaetae blades which are long and slender. Several subspecies of S. erinaceus were described on the basis of differences in shapes and sizes of their compound chaetae; such differences are enough to consider them as distinct species. The species is named in honour of Gesa Hartmann-Schröder, an expert on syllid species.
Sphaerosyllis bardukaciculata is a species belonging to the phylum Annelida, a group known as the segmented worms. Sphaerosyllis bardukaciculatan is similar to Sphaerosyllis aciculata from Florida; its chaetae are almost identical; the former, however, differs by having longer antennae and anal cirri, as well as parapodial glands with granular material. The animal's name is derived from the Aboriginal word barduk, meaning "near", alluding to the aforementioned likeness with S. aciculata.
Terebellides is a genus of polychaete worms in the family Trichobranchidae.
Chrysopetalidae is a family of polychaete worms. The body is short or elongated, with few or numerous segments. All segments bear on their dorsal side a fan or a transverse row of paleae. The cephalic lobe has tentacles and eyes and the buccal segment has two or four tentacular cirri on each side. The parapodia are uniramous or biramous, with dorsal cirri upon all segments. The ventral bristles are compound.
Ramisyllis multicaudata is a species of polychaete worm in the family Syllidae. It was found in Darwin Harbour, Australia, where it was living within the tissues of a sponge of the genus Petrosia. It was the second branching species of polychaete worm to have been discovered, the first having been Syllis ramosa, a deep water species, more than a century earlier. In 2022, a second species in R. multicaudata's genus, Ramisyllis kingghidorahi, was described from specimens taken off the coast of Sado Island, Japan.
Oxydromus is a genus of annelids belonging to the family Hesionidae.
Prosphaerosyllis is a genus of polychaetes belonging to the family Syllidae.
Odontosyllis is a genus of annelids belonging to the family Syllidae.
Haplosyllis is a genus of annelids belonging to the family Syllidae.
Lumbrineris is a genus of polychaetes belonging to the family Lumbrineridae.
Pionosyllis is a genus of polychaetes belonging to the family Syllidae.