Description: Family Glyceridae (bloodworms) is a distinctive family of benthic polychaetes with a prostomium that is shaped like a cone (as if the face of the animal is covered by a funnel), tapered to a point (often with annulated rings), and with 4 tiny antennae (sometimes damaged or hard to see) at the tip (photo). Sometimes eyes are apparent. Their pharynx, when everted into a proboscis, has 4 hook-like jaws and can be up to 1/3 the length of the animal. Glycera americana has biramous parapodia (except for the first 2 pairs), which have 2 presetal and 2 postsetal lobes. It also has long, branched, fingerlike, retractile gills on the posteriodorsal surfaces of the parapodia (if the gills are partly retracted it may not be evident that they are branched, and if fully retracted they may appear only as a thin, loose patch of epidermis on the parapodium). The notosetae are simple but the neurosetae are compound (composed of more than one section). Segments are clearly wider than long. Nearly all body segments except the first two are similar, but the body tapers gradually toward the posterior end. Total length to 35 cm, not c Glycera_americana.html ounting the everted pharynx. Color usually iridescent pink or greenish-blue. How to Distinguish from Similar Species: The shape and location of the gills is characteristic for this species. Several other Glycera species have no gills, have globular or blister-shaped gills, or the gills arise from the anterior or dorsal part of the parapodia. Family Goniadidae also have a funnel-shaped prostomium with 4 small antennae but have only 2 large jaws and 2 groups of smaller jaws on their everted pharynx. Their bodies are also divided into 2-3 distinct regions while most segments except the first two of Glycerids are similar. Geographical Range: Pacific coast of North and South America from British Columbia to Chile; also Japan, Australia, and New Zealand. On the Atlantic coast from Canada to Brazil. Depth Range: Intertidal to 315 m depth Habitat: Burrows through mixed sand/mud ; sometimes under rocks or among the roots of eelgrass. Biology/Natural History: This worm is a rapid burrowing predator and readily everts its long, cylindrical, fanged pharynx both to capture prey and to pull itself through soft sediment. The jaws on the pharynx are venemous with a neurotoxin that includes serotonin and proteolytic enzymes and can cause inflammation in humans. Its main prey is other polychaetes. Since its anus appears to be nonfunctional, after a meal it regurgitates the undigested portion through the pharynx. When sexually mature (in summer) the animal loses its pharynx and its body fills with gametes. It then swarms up into the water column as an epitoke in a breeding swarm with other epitoke individuals of its species. It releases its gametes through its mouth or bursting out through the skin, then dies. Members of Famuily Glyceridae are called bloodworms because if they
are cut they often release large quantities of bright-red blood or coelomic
fluid. The red color of the fluid is due to hemoglobin which is contained
within red corpuscles.
References:Dichotomous Keys:Carlton, 2007 Kozloff, 1987, 1996 General References:
Scientific Articles:
Web sites:
General Notes and Observations: Locations, abundances, unusual behaviors:
Authors and Editors of Page:
Salish Sea Invertebrates web site provided courtesy of Walla
Walla University
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