The

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

''Glycera'' is a group of

polychaetes Polychaeta () is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are m ...

(bristle worms) commonly known as bloodworms. They are typically found on the bottom of shallow marine waters, and some species (e.g. common bloodworms) can grow up to in length. Although both are visually-similar and commonly-used as

fishing bait Fishing bait is any bait (luring substance), luring substance used specifically to attract and fishing, catch fish, typically when angling with a fish hook, hook and fishing line, line. There are generally two types of baits used in angling: '' ...

, bloodworms are biologically-distinct from

lugworm ''Arenicola'', also known as sandworms, is a genus of capitellid annelid worms comprising the lugworms and black lugs. ''A.cristata'' is the dominant warm-water lugworm on the shores of North America and Humboldt Bay, California. ''A. caroledna' ...

Anatomy

Bloodworms have a creamy pink color, as their pale skin allows their red body fluids that contain

haemoglobin Hemoglobin (haemoglobin, Hb or Hgb) is a protein containing iron that facilitates the transportation of oxygen in red blood cells. Almost all vertebrates contain hemoglobin, with the sole exception of the fish family Channichthyidae. Hemoglobi ...

to show through. This is the origin of the name "bloodworm". At the 'head', bloodworms have four small antennae and small fleshy projections called

parapodia In invertebrates, the term parapodium ( Gr. ''para'', beyond or beside + ''podia'', feet; : parapodia) refers to lateral outgrowths or protrusions from the body. Parapodia are predominantly found in annelids, where they are paired, unjointed late ...

running down their bodies. Bloodworms can grow up to in length. Bloodworms are carnivorous. They feed by extending a large

proboscis A proboscis () is an elongated appendage from the head of an animal, either a vertebrate or an invertebrate. In invertebrates, the term usually refers to tubular arthropod mouthparts, mouthparts used for feeding and sucking. In vertebrates, a pr ...

that bears four hollow jaws. The jaws are connected to glands that supply venom which they use to kill their prey, and their bite is painful even to a human. They are preyed on by other worms, bottom-feeding

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

crustacea Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthrop ...

, and

gull Gulls, or colloquially seagulls, are seabirds of the subfamily Larinae. They are most closely related to terns and skimmers, distantly related to auks, and even more distantly related to waders. Until the 21st century, most gulls were placed ...

s. Reproduction occurs in midsummer, when the warmer water temperature and lunar cycle among other factors triggers sexually mature worms to transform into a non-feeding stage called the epitoke. With enlarged

, they swim to the surface of the water where both sexes release

gamete A gamete ( ) is a Ploidy#Haploid and monoploid, haploid cell that fuses with another haploid cell during fertilization in organisms that Sexual reproduction, reproduce sexually. Gametes are an organism's reproductive cells, also referred to as s ...

s, and then die. The first stage in many forms of bloodworm is a zooplanktonic stage followed by the

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from the Ancient Greek word (), meaning "the depths". ...

instar An instar (, from the Latin '' īnstar'' 'form, likeness') is a developmental stage of arthropods, such as insects, which occurs between each moult (''ecdysis'') until sexual maturity is reached. Arthropods must shed the exoskeleton in order to ...

where the familiar segmented red larvae develop protected by silk tubes made in the bottom silt. These larvae progress from tiny pale opaque worms to the larger red larvae of in length or longer over a period as short as 2–3 weeks in optimum conditions. These animals are unique in that they contain a lot of copper without being poisoned. Their jaws are unusually strong since they too contain the metal in the form of a copper-based chloride biomineral, known as atacamite, in crystalline form. It is theorized that this copper is used as a catalyst for its venomous bite. In ''Glycera dibranchiata'', the jaws are a composite of melanin and 10% copper.

Systematics

''Glycera'' is the

type genus In biological taxonomy, the type genus (''genus typica'') is the genus which defines a biological family and the root of the family name. Zoological nomenclature According to the International Code of Zoological Nomenclature, "The name-bearin ...

of the family Glyceridae. It contains the following species as of October 2023: *'' Glycera africana'' Arwidsson, 1899 *'' Glycera alba'' (O.F. Müller, 1776) *'' Glycera amadaiba'' Imajima, 2003 *'' Glycera amboinensis'' McIntosh, 1885 *'' Glycera americana'' Leidy, 1855 *'' Glycera asymmetrica'' Day, 1973 *'' Glycera baltica'' (Eisenack, 1939) † *'' Glycera bassensis'' Böggemann & Fiege, 2001 *'' Glycera benguellana'' Augener, 1931 *'' Glycera benhami'' Böggemann & Fiege, 2001 *'' Glycera branchiopoda'' Moore, 1911 *'' Glycera brevicirris'' Grube, 1870 *'' Glycera calbucoensis'' Hartmann-Schröder, 1962 *'' Glycera capitata'' Örsted, 1842 *'' Glycera carnea'' Blanchard in Gay, 1849 *'' Glycera celtica'' O'Connor, 1987 *'' Glycera chirori'' Izuka, 1912 *'' Glycera cinnamomea'' Grube, 1874 *'' Glycera decipiens'' Marenzeller, 1879 *'' Glycera dentribranchia'' Lee, 1985 *'' Glycera derbyensis'' Hartmann-Schröder, 1979 *'' Glycera dibranchiata'' Ehlers, 1868 *'' Glycera diva'' Böggemann, 2009 *'' Glycera dubia'' (Blainville, 1825) *'' Glycera ehlersi'' Arwidsson, 1899 *'' Glycera fallax'' Quatrefages, 1850 *'' Glycera fundicola'' Chamberlin, 1919 *'' Glycera gilbertae'' Böggemann & Fiege, 2001 *'' Glycera glaucopsammensis'' Charletta & Boyer, 1974 † *'' Glycera guatemalensis'' Böggemann & Fiege, 2001 *'' Glycera guinensis'' Augener, 1918 *'' Glycera hasidatensis'' Izuka, 1912 *'' Glycera heteropoda'' Hartmann-Schröder, 1962 *'' Glycera incerta'' Hansen, 1882 *'' Glycera juliae'' Magalhães & Rizzo, 2012 *'' Glycera kerguelensis'' McIntosh, 1885 *'' Glycera knoxi'' Kirkegaard, 1995 *'' Glycera lamelliformis'' McIntosh, 1885 *'' Glycera lancadivae'' Schmarda, 1861 *'' Glycera lapidum'' Quatrefages, 1866 *'' Glycera longipinnis'' Grube, 1878 *'' Glycera macintoshi'' Grube, 1877 *'' Glycera macrobranchia'' Moore, 1911 *'' Glycera madagascariensis'' Böggemann & Fiege, 2001 *'' Glycera mauritiana'' Grube, 1870 *'' Glycera mexicana'' (Chamberlin, 1919) *'' Glycera micrognatha'' Schmarda, 1861 *'' Glycera nana'' Johnson, 1901 *'' Glycera natalensis'' Day, 1957 *'' Glycera neorobusta'' Imajima, 2009 *'' Glycera nicobarica'' Grube, 1866 *'' Glycera noelae'' Böggemann, Bienhold & Gaudron, 2012 *'' Glycera okai'' Imajima, 2009 *'' Glycera onomichiensis'' Izuka, 1912 *'' Glycera ovigera'' Schmarda, 1861 *'' Glycera oxycephala'' Ehlers, 1887 *'' Glycera pacifica'' Kinberg, 1866 *'' Glycera papillosa'' Grube, 1857 *'' Glycera pilicae'' Szaniawski, 1974 † *'' Glycera polygona'' Risso, 1826 *'' Glycera posterobranchia'' Hoagland, 1920 *'' Glycera profundi'' Chamberlin, 1919 *'' Glycera prosobranchia'' Böggemann & Fiege, 2001 *'' Glycera pseudorobusta'' Böggemann & Fiege, 2001 *'' Glycera robusta'' Ehlers, 1868 *'' Glycera russa'' Grube, 1870 *'' Glycera rutilans'' Grube in McIntosh, 1885 *'' Glycera sagittariae'' McIntosh, 1885 *'' Glycera semibranchiopoda'' Imajima, 2009 *'' Glycera sheikhmujibi'' Hossain & Hutchings, 2020 *'' Glycera southeastatlantica'' Böggemann, 2009 *'' Glycera sphyrabrancha'' Schmarda, 1861 *'' Glycera subaenea'' Grube, 1878 *'' Glycera taurica'' Czerniavsky, 1881 *'' Glycera tenuis'' Hartman, 1944 *'' Glycera tesselata'' Grube, 1863 *'' Glycera tridactyla'' Schmarda, 1861 *'' Glycera unicornis'' Lamarck, 1818

Use by humans

''Glycera'' worms are sold commercially in tackle shops as bait for saltwater fishing.

References

"Fishing for Allergens: Bloodworm-Induced Asthma" study at the Allergy, Asthma & Clinical Immunology (AACI) site {{DEFAULTSORT:Glycera (annelid) Polychaete genera Phyllodocida ru:Glycera alba