The Polydiversity of Polychaete Worms

Alexander Semenov, well known underwater photographer from the Russian Federation, has posted a set of stunningly gorgeous worm photos on Bēhance.

Creatures from dreams and nightmares are here. They are real and they are unbelievably beautiful.

From the depths of the cold White Sea to the coral reefs of the Great Barrier Reef in Australia. Some of them were collected recently and they are still undescribed! They’re only a drop in the whole diversity of polychaetes.

SOURCE: Worms Renaissance, 7 March 2014

The word ‘polychaete’

Each body segment of a polychaete worm has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are made of chitin. Polychaetes are sometimes referred to as bristle worms. [WP]


Everyone watch this video about how powerful and capable annelids are or I won’t love you anymore


Christmas Tree Worm (Spirobranchus giganteus)

…a species of tube-building serpulid polychaete worm that is widely distributed throughout tropical oceans worldwide, ranging from the Caribbean to the Indo-Pacific. S. giganteus commonly inhabit the heads of corals and like other serpulids it secrets a calcareous tube around its body which serves as its home and protection. Like other tube-building worms S. giganteus is a filter feed and will use its two brightly colored ‘Christmas trees’ [which are specialized mouth appendages laced with feather-like tentacles called radioles] to filter microorganisms from the water, which are transferred straight into its digestive tract. They are also used in respiration.


Animalia-Annelida-Polychaeta-Canalipalpata-Serpulidae-Spirobranchus-S. giganteus

Video/Image: Bart Shepherd and Nick Hobgood

Chloeia sp. 

This creature may seem like a caterpillar, but it is a marine polychaete annelid, which has no relation to the Lepidoptera. It belongs to the genus Chloeia in the Family Amphinomidae. 

Amphinoids are also known as “fireworms” and they are unusual, compared to other polychaetes, in having such features as calcified setae. Setae are bristle- or hair-like structures on every segment of their bodies.

Fireworms mainly live in the sea; they have been responsible for ‘bristleworm stingings’ and their large setae are reputed to be filled with toxin.

However, an examination of the setae and parapodia of Eurythoe complanata, Chloeia flava and Pherecardia striata using histological and scanning electron microscope techniques, showed no evidence for hypothesized toxin-producing glands communicating with the parapodial setae. Setae were hollow, but empty. It is suggested that these polychaetes are urticating rather than toxic.

References: [1] - [2]

Photo credit: ©Francesco De Marchi

Locality: Tulamben, Bali, Indonesia.

Made with Flickr

Kinabalu Giant Earthworm (Pheretima darnleiensis)

…a species of Megascolecid earthworm that is native to Mount Kinabalu in Borneo, New Guinea and surrounding islands. true to its name P. darnleiensis can grow quite large and can grow to around 70 cm (27 in) long. Like smaller earthworms P. darnleiensis burrows underground and likely feeds on organic waste. P. darnleiensis is one of the main prey items of the Kinabalu Giant Red Leech (Mimobdella buettikofen).


Animalia-Annelida-Clitellata-Oligochaeta-Haplotaxida-Megascolecidae-Pheretima-P. darnleiensis

Images: Ivan Kwan and Ch'ien C. Lee

Golden fireworm  (Golden Bristle Worm)

This is a marine polychaete of the species Chloeia flava commonly referred to as Golden fireworm, which can reach up to 10 cm long and occurs in the  Indo-Pacific. 

These polychaetes have a bad reputation because their bristles (setae) are painfully urticating, hence their common name of fireworm.

[Annelida - Polychaeta - Amphinomida - Amphinomidae]

References: [1]

Photo credit: ©Ben Naden | Locality: Bali, Indonesia

Made with Flickr

The Nereid Worm Alitta virens 
Photography by Alexander Semenov
All rights reserved

Part of a set of macro photographs taken in the lab

WikipediaAlitta virens (sandworm / king ragworm) is an annelid worm that burrows in wet sand and mud. It is classified as a polychaete in the family Nereididae.

  • Sandworms eat seaweed and microorganisms;
  • they often reach great length, sometimes exceeding four feet;
  • they have numerous, highly vascularized parapodia along both sides of their bodies;
  • they have two large pincer teeth which are capable of biting humans.

The parapodia [bottom photo] function both as external gills and as means of locomotion.

An aggregate of methane ice worms (Hesiocaeca methanicola) that inhabit in methane hydrate ice. Studies suggest that these worms eats chemotrophic autotroph bacteria living near the chemicals in the hydrate

Sabellid Worms, Tulamben (Bali, Indonesia) | ©Francesco Ricciardi

Bispira is a genus of tube-dwelling polychaete worms belonging to the family Sabellidae. It lives mainly on rocky substrata and reaches a length of up to 10cm.

Like other sabellid worms, gas exchange is through a crown of tentacles that also serve as a filtration-feeding system. The worm has no mobility outside the confines of the tube, and the filtration mechanism is susceptible to clogging if excessive suspended solids are present [source]. 

Animalia - Annelida - Polychaeta - Canalipalpata - Sabellidae - Bispira


Myzostoma cirriferum

Taxonomy: Animalia, Annelida, Myzostomida, Myzostomatidae, Myzostoma, M. cirriferum

Description: M. cirrifeum are short, squat annelids with translucent bodies and prominent marginal cirri. Their parapodia have evolved into small gripping appendages, with hooks for attaching themselves to their hosts. These polychaetes only reach a few mm in diameter.

Lifestyle: Alongside all other myzostomids, M. cirrifeum is an obligate parasite of echinoderms. This species in particular is found on the crinoid Antedon bifida, which are found on the coasts of north-western Europe. After birth, the larval worm is taken by the crinoid as if it were a food particle, where they attach themselves to the host’s podia. From there, they attach to the abulacral grooves, where they form a cyst-like structure for protection. Males and hermaphoriditic individuals more around on the host crinoids

Photos by Christoph Bleidorn and aphotomarine.

Mediterranean Fanworm (Sabella spallanzanii)

Also known as the European Fanworm or Pencil Worm, the Mediterranean Fanworm is a species of feather duster worm (Sabellidae) that is native to shallow waters in the northeastern Atlantic Ocean and in the Mediterranean Sea, extended from the United Kingdom and Ireland, through France, Spain and Portugal to Italy, Greece, and Turkey. It has also been accidentally been introduced to various other parts of the world. Like other “feather duster worms”, the Mediterranean fanworm is a filter feeder, feeding on bacteria, zooplankton, phytoplankton, and various other organic matter. These food items are collected in its “fan” and brought down towards the mouth. Sabella spallazanii gets its species name in commemoration of the Italian biologist Lazzaro Spallanzani.


Animalia-Annelida-Polychaeta-Canalipalpata-Sabellida-Sabellidae-Sabella-S. spallanzanii

Image: Anders Finn Jorgensen

Bearded fireworm - Hermodice carunculata

Hermodice carunculata (Amphinomida - Amphinomidae) is a marine bristle-worm widespread and abundant infound in reef habitats throughout the Atlantic Ocean, including the Gulf of Mexico, the Caribbean Sea, the South American and African Atlantic coasts, and the Mediterranean and Red Seas.

Bearded fireworms are often strikingly beautiful and very colorful, usually between 5-10 centimeters in length, but can reach up to 35 centimeters. On both sides they are endowed with a group of poisonous white bristles that flare out when the worm is disturbed. The bristles are hollow, venom-filled chaeta which easily penetrate flesh and then break off if this worm is handled. They produce an intense burning irritation in the area of contact, hence the common name of the species. The sting can also lead to nausea and dizziness. This sensation lasts up to a few hours, but a painful tingling can continue to be felt around the area of contact.

They are facultative corallivores, and their destructive feeding behavior is known to stunt the growth of the hydrocoral Millepora complanata in the Caribbean Sea, and in the Mediterranean Sea, Hermodice carunculata acts as a winter reservoir and possibly a vector for the coral-bleaching pathogen Vibrio shiloi

References: [1] - [2]

Photo credit: ©Philippe Guillaume (CC BY-NC-ND 2.0) | Locality: Tenerife, Canary Islands, Spain (2010)

Made with Flickr