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Reef Zoobenthos
The eunicids are medium-sized (1-2cm) worms with round-shaped body,
short parapodia and a fringe of gills on their dorsal sides. Most eunicid
species can be found in the cryptofaunal communities, in branches of dead
corals, under stones in holes and trenches of flat rocks. They can also stretch
out their pharynx armed with double mandibles and with rows maxillae.
Several species of this group bore holes in solid lime rocks and even in living
corals (Lyzidice, Palola, Eunice, Schemancephala). The young vorms
wander freely around on the bottom, while the adults build permanent tubes
or live in holes bored and then abandoned by sipunculid worms. Some
species make their own holes is soft or even solid bottom substrate (Day
1967). Many eunicids are commensals of sponges, molluscs, holothurians,
and hydroids. Some (Arabella) are parasites. The eunicids also perform the
wedding dource, the same as the nereids. Among the nereids there are
specialized predators feeding on other worms, on ostracods and other
meiobenthos (E. aphroditois) , and phytophages feeding on coralline algae
and periphyton (E. viridis). But most of the eunicids are omnivores animal
food dominating in their food ration (Day 1967; Fauchald and Jumars 1979).
Most common among the eunicids are: Eunice atra, E. cincta, E. australis,
E. antennata, E. caribbea, Palola siciliensis, Lysidice collaris, L. ninetta,
Nematonereis unicornis, Drilonereis talcata, Lambrinereis etraura, Marphysa
corallina, Arabella mutans, and A. iricolor.
Syllids are small, flat worms with minute, fine parapodia. Their size is 2 to
20 mm. The syllids are recognized as one of the most important component
of the meiobenthos often dominating the communities of flat- of rubblebottom areas and even the soft bottom (Kohn and Lloyd 1973; Hutchings
1974). The extremely poverful outstretched pharynx of some syllids has a
special suction device, the proventriculus. With the aid of it the worms can
suck out the polyps of hydroids. Their mouth is armed with one large tooth
and several smaller ones. Most syllids are predators. They graze hydroids,
bryozoans, ascidians, sponges, zoantharians. But there are among them also
omnivorous worms (genus Eusyllis) , which live in sand and feed on
microphytobenthos, on ostracods and micromolluscs. An important feature
of syllids is their ability for asexual breeding by simple division of the body
into several pieces. Each new piece develops head and tail at its ends and
becomes a new worm. Because of this ability they may quickly colonize the
bottom substrates and their populations attain large numbers and form a
considerable part of the biomass (Hutchings 1974). The most common
species of syllids are: Syllis cornuta, S. alternata, S. spongicola, S. amica, S.
gracilis, S. exilis, Opistosyllis laevis, Tryanosyllis zebra, Exogene longicornis,
E. dispar, E. verugira, Brandia rhopalophera, and Odontosyllis ctenostoma.
Polynoids are relatively large worms. Their body is covered by brightly
colored scales. They live mostly under boulders and stones and are a
remarkable element of the reef cryptofauna. They are predators feeding on
other worms and eggs laid by molluscs. Their mass species are: Hermothoe
indica, H. dictyophora, Lepidonotus carinulatus, L. glaucus, L. jukesi, L.
jachsoni, Dendropoma sp.
Reef Zoobenthos
The eunicids are medium-sized (1-2cm) worms with round-shaped body,
short parapodia and a fringe of gills on their dorsal sides. Most eunicid
species can be found in the cryptofaunal communities, in branches of dead
corals, under stones in holes and trenches of flat rocks. They can also stretch
out their pharynx armed with double mandibles and with rows maxillae.
Several species of this group bore holes in solid lime rocks and even in living
corals (Lyzidice, Palola, Eunice, Schemancephala). The young vorms
wander freely around on the bottom, while the adults build permanent tubes
or live in holes bored and then abandoned by sipunculid worms. Some
species make their own holes is soft or even solid bottom substrate (Day
1967). Many eunicids are commensals of sponges, molluscs, holothurians,
and hydroids. Some (Arabella) are parasites. The eunicids also perform the
wedding dource, the same as the nereids. Among the nereids there are
specialized predators feeding on other worms, on ostracods and other
meiobenthos (E. aphroditois) , and phytophages feeding on coralline algae
and periphyton (E. viridis). But most of the eunicids are omnivores animal
food dominating in their food ration (Day 1967; Fauchald and Jumars 1979).
Most common among the eunicids are: Eunice atra, E. cincta, E. australis,
E. antennata, E. caribbea, Palola siciliensis, Lysidice collaris, L. ninetta,
Nematonereis unicornis, Drilonereis talcata, Lambrinereis etraura, Marphysa
corallina, Arabella mutans, and A. iricolor.
Syllids are small, flat worms with minute, fine parapodia. Their size is 2 to
20 mm. The syllids are recognized as one of the most important component
of the meiobenthos often dominating the communities of flat- of rubblebottom areas and even the soft bottom (Kohn and Lloyd 1973; Hutchings
1974). The extremely poverful outstretched pharynx of some syllids has a
special suction device, the proventriculus. With the aid of it the worms can
suck out the polyps of hydroids. Their mouth is armed with one large tooth
and several smaller ones. Most syllids are predators. They graze hydroids,
bryozoans, ascidians, sponges, zoantharians. But there are among them also
omnivorous worms (genus Eusyllis) , which live in sand and feed on
microphytobenthos, on ostracods and micromolluscs. An important feature
of syllids is their ability for asexual breeding by simple division of the body
into several pieces. Each new piece develops head and tail at its ends and
becomes a new worm. Because of this ability they may quickly colonize the
bottom substrates and their populations attain large numbers and form a
considerable part of the biomass (Hutchings 1974). The most common
species of syllids are: Syllis cornuta, S. alternata, S. spongicola, S. amica, S.
gracilis, S. exilis, Opistosyllis laevis, Tryanosyllis zebra, Exogene longicornis,
E. dispar, E. verugira, Brandia rhopalophera, and Odontosyllis ctenostoma.
Polynoids are relatively large worms. Their body is covered by brightly
colored scales. They live mostly under boulders and stones and are a
remarkable element of the reef cryptofauna. They are predators feeding on
other worms and eggs laid by molluscs. Their mass species are: Hermothoe
indica, H. dictyophora, Lepidonotus carinulatus, L. glaucus, L. jukesi, L.
jachsoni, Dendropoma sp.