Nereis Vexillosa Class: Polychaeta Order: Phyllodocida the Large Mussel Worm Family: Nereidae

Home , Nereididae, Nereis, Nereis vexillosa

Phylum: Annelida Nereis vexillosa Class: Polychaeta Order: Phyllodocida The large mussel worm Family: Nereidae

Taxonomy: One may find several subjective individuals are modified for swimming and are synonyms for Nereis vexillosa, but none are wide and plate-like (Kozloff 1993). widely used currently. Setae (chaetae): Notopodia bear homogomph spinigers anteriorly (Fig. 8d) that Description gradually transition to few short homogomph Size: Individuals living in gravel are larger falcigers posteriorly (Fig. 8a). Both anterior than those on pilings and sizes range from and posterior neuropodia have homo- and 150–300 mm in length (Johnson 1943; heterogomph spinigers (Fig. 8c, d) and Ricketts and Calvin 1971; Kozloff 1993) and heterogomph falcigers (Fig. 8b) (Nereis, Hilbig up to 12 mm in width (Hartman 1968). 1997). Acicula, or heavy internal black Epitokous adults are much larger than spines, are found on all noto- and neuropodia sexually immature individuals. For example, (Figs. 6). one year old heteronereids were at least 560 Eyes/Eyespots: Two pairs of small ocelli are mm in length (Johnson 1943). present on the prostomium (Fig. 2). Color: Body color grey and iridescent green, Anterior Appendages: Prostomium bears blue and red body color. Females have more two small antennae and two massive palps a reddish posterior than males (Kozloff 1993). each with small styles. Four pairs of General Morphology: Thick worms that are tentacular cirri are also present and the two rather wide for their length (Fig. 1). dorsal pairs are longest (Fig. 2). Body: More than 100 body segments are Branchiae: Absent (Blake and Ruff 2007). normal for this species (Hartman 1968), the Burrow/Tube: Newly hatched animals build illustrated specimen has 105 segments (Fig. flimsy mucus and sand tubes (Johnson 1943). 1). Nereids are recognizable by their anterior Adult worm to tube length ratio is 1.65:1 (Roe appendages including two prostomial palps 1975). and four peristomial tentacular cirri (see Pharynx: The pharynx bears a distinct Anterior appendages) (Fig. 2) (Blake and eversible proboscis. The everted proboscis Ruff 2007). has two rings, oral (or proximal) and distal (or Anterior: Prostomium pyriform and maxillary) and terminates with two fang- widest posteriorly (Fig 2). shaped jaws, with 6–8 teeth (Fig. 3, 4). The Trunk: Thick segments that are wider oral ring is used largely in burrowing, while than they are long, gently tapers to the distal ring is used in feeding (Barnes and posterior (Fig. 1). Head 1977). Each ring is equipped with Posterior: Pygidium bears a posterior many papillae and conical paragnaths and cirrus with four, fine, accessory lobes their patterns are taxonomically relevant. (Fig. 1) that are often broken during Paragnaths (conical teeth) on both oral and collection. maxillary rings are arranged as follows: Area I Parapodia: Parapodia are of typical nereid has several small cones in tandem; Area II biramous structure (Figs. 5, 6, 7) from the has an oblique, small transverse patch (Fig. third setiger (Hilbig 1997). Posterior 3); Area III has a circular patch; Area IV notopodial lobes gradually change into long (paired) with an oblique patch of several rows, strap-like ligules (Fig. 6), with dorsal cirrus both are ventral; Area V has no paragnaths; inserted terminally (most important species Area VI with a mass of 6–9 or more and both characteristic). The parapodia of epitokous are dorsal (Fig. 3); Areas VII and VIII both

A publication of the University of Oregon Libraries and the Oregon Institute of Marine Biology Individual species: http://hdl.handle.net/1794/12674 and full 3rd edition: http://hdl.handle.net/1794/18839 Email corrections to: [email protected] have continuous bands of many paragnaths, Other morphologically similar those anterior being largest and both are species include those in the genus ventral (Fig. 4). Neanthes. Neanthes limnicola individuals Genitalia: are usually pale and translucent, not Nephridia: distinctly green as in N. vexillosa. Neanthes brandti has been at times considered a Possible Misidentifications subspecies or a synonym of N. virens, The prostomia of nereid worms are (Breton et al. 2004) and is large, sand- quite alike, with four eyes, a pair of frontal dwelling and green in color like N. vexillosa. antennae and biarticulate palps, and 3–4 However, N. brandti is usually paler pairs of tentacular cirri. Common local nereids are those in the genera Neanthes and Nereis. ventrally and, in contrast to N. vexillosa, it Neanthes species have only homogomph has many teeth on all areas of the spinigerous setae in the posterior notopodia. proboscis, its posterior parapodial lobes are The genus Neanthes is further distinguished leaf-like, not long and strap-like. N. brandti by having only conical paragnaths on both also has no falcigers in the posterior proboscis rings, and biramous parapodia with notopodia and its ecological niche is composite setae (Hartman and Reish 1950). different, it does not live in mussel beds or Neanthes have spinigerous notosetae only on pilings. Neanthes succinea is one of the (Hilbig 1997). The morphologically similar most common nereids in the Northeast genus, Nereis sensu stricto, is characterized Pacific and has a very enlarged posterior by species with spinigerous notosetae in the notopodial lobes, with a small distal dorsal anterior half of the body and falcigerous cirrus attached at the end of the lobe (Blake notosetae posteriorly (Smith 1959; Pettibone and Ruff 2007). N. succinea is thought to 1963). be a more southern form (although it has Common local Nereis species been reported from Netarts Bay). include 6–7 species (Blake and Ruff 2007). Nereis eakini, from rocky habitats, that has Ecological Information a long prostomium and proboscis rings Range: Type localities are Alaska and covered with small round paragnaths. The Siberia. Known range includes eastern bright green Nereis grubei has greatly Siberia to Alaska and south to central expanded posterior notopodial parapodial California (Hartman 1968). lobes and no paragnaths in area V of the Local Distribution: Coos Bay distribution proboscis. Nereis procera is subtidal in includes many sites and, within Oregon, N. sand, has tiny eyes, a very long body, and vexillosa has also been found in Yaquina Bay. unusually inconspicuous paragnaths on its Habitat: Individuals occur among heavy proboscis (Hartman 1968). Nereis algae cover, eelgrass, bark, and under rocks latescens is common amongst algal or cobblestones. Their preferred substrate is holdfasts and their dorsum bears transverse sand or mud mixed with sand. N. vexillosa lines of brown pigment (Blake and Ruff also occurs in mussel beds and barnacle 2007). Nereis pelagica is an intertidal to clusters on intertidal pilings along the open subtidal species with dark parapodial lobes. coast (Blake and Ruff 2007). The common and abundant Nereis Salinity: Nereis vexillosa is strictly a marine vexillosa, can be differentiated from the species. above species by its olive green to brown Temperature: Cold water to temperate color where it is found in many diverse (Johnson 1943). marine environments, especially in mussel Tidal Level: Intertidal and shallow water beds. Furthermore, it has distinct greatly (Johnson 1943). elongated, strap-like notopodial lobes in the Associates: Occurs with Neanthes virens, in posterior parapodia. mussel beds and with the scaleworm

Hiebert, T.C. 2015. Nereis vexillosa. In: Oregon Estuarine Invertebrates: Rudys' Illustrated Guide to Common Species, 3rd ed. T.C. Hiebert, B.A. Butler and A.L. Shanks (eds.). University of Oregon Libraries and Oregon Institute of Marine Biology, Charleston, OR. Halosydna, porcelain crab Petrolisthes, and Longevity: Two-year life-span (Roe 1975). isopod Cirolana. Growth Rate: Varies greatly. At 4–12 Abundance: Ubiquitous (Ricketts and Calvin months and 60 segments, adult species 1971). The most abundant large annelid of characteristics are conspicuous, including the Pacific Northwest (Johnson 1943), but strap-like parapodial lobes (Johnson 1943). varies in abundance throughout wide Food: N. vexillosa is omnivorous and prefers geographical range (Ricketts and Calvin fresh animal food, and will reject dead food. 1971). About 22 individuals/m2 were reported This species is not a scavenger by preference in Mitchell Bay, Washington (Roe 1975). (Johnson 1943). Nereids use their jaws to tear apart and eat pieces of algae (Kozloff Life-History Information 1993). Young build flimsy mucus and sand Reproduction: Nereis vexillosa has tubes, and rarely leave them completely to heteronereid a form (called an epitoke) feed. characterized by modified parapodia (Fig. 7). Predators: Sometimes preyed upon by These epitokes swarm at night in summer nemertean Paranemertes peregrina (Roe months (June in Coos Bay and March-August 1970). Widely used by man for fish bait. in Washington, Fernald et al. 1987). Males Behavior: Very active worm that can bite appear first near water's surface, then human collector. females. Large (200–250 µm in diameter) oocytes are released from the females in a Bibliography gelatinous mass and both female and egg mass sink to the benthos. Both adults usually 1. BARNES, R. S. K., and S. M. HEAD. die shortly thereafter (Fernald et al. 1987). 1977. Variation in paragnath number Eggs are found in a firm, irregular, gelatinous in some British populations of mass, 2.5–7.5 cm in diameter, translucent estuarine polychaete Nereis and blue green, green or brown when freshly diversicolor. Estuarine and Coastal laid. Eggs can withstand strong wave action. Marine Science. 5:771-781. N. vexillosa is the only nereid with a solid egg 2. BLAKE, J. A., and R. E. RUFF. 2007. mass. Polychaeta, p. 309-410. In: The Light Larva: Larval development was described by and Smith manual: intertidal Johnson (1943). Pelagic and lecithotrophic invertebrates from central California to larvae hatch from the gelatinous egg mass Oregon. J. T. Carlton (ed.). University between 3–5 setiger stages. Survivorship of of California Press, Berkeley, CA. larvae is reduced due to ingestion by the co- 3. BRETON, S., F. DUFRESNE, G. occuring terebellid polychaete Eupolymnia DESROSIERS, and P. BLIER. 2004. heterobranchia (Wilson 1980). When larvae Morphological variation in Nereis are 1–2 weeks old (4–6 setiger stages), they (Neanthes) virens (Polychaeta : build mucus tubes and begin to feed (Roe Nereididae) populations. Journal of the 1975; Fernald et al. 1987). Marine Biological Association of the Juvenile: In the field, juveniles have 8–25 United Kingdom. 84:983-985. setigers from 3–5 weeks, are one half adult 4. FERNALD, R. L., C. O. HERMANS, T. size after one year and are fully grown and C. LACALLI, W. H. WILSON, JR, and sexually mature the following year (Roe S. A. WOODIN. 1987. Phylum 1975). Juveniles can grow quickly in the lab, Annelida, Class Polychaeta, p. 138- on a diet of other polychaetes (Johnson 195. In: Reproduction and 1943). In the field, they can be territorial two development of marine invertebrates weeks after hatching (Roe 1975). of the northern Pacific coast. M. F. Researchers have shown that N. vexillosa is Strathmann (ed.). University of less likely to burrow into sediment that has Washington Press, Seattle, WA. been recently disturbed (e.g., by erosion, 5. HARTMAN, O. 1968. Atlas of the mixing, fresh feces, burrow trails and feeding errantiate polychaetous annelids from tracks) (Woodin et al. 1995). California. Allan Hancock Foundation,

A publication of the University of Oregon Libraries and the Oregon Institute of Marine Biology Individual species: http://hdl.handle.net/1794/12674 and full 3rd edition: http://hdl.handle.net/1794/18839 Email corrections to: [email protected] University of Southern California, Los 11. RICKETTS, E. F., and J. CALVIN. Angeles. 1971. Between Pacific tides. Stanford 6. HARTMAN, O., and D. J. REISH. University Press, Stanford, California. 1950. The Marine annelids of Oregon. 12. ROE, P. 1975. Aspects of life-history Oregon State College, Corvallis, and of territorial behavior in young Oregon. individuals of Platynereis 7. HILBIG, B. 1997. Family Nereididae, bicanaliculata and Nereis vexillosa p. 291-316. In: Taxonomic atlas of the (Annelida: Polychaeta). Pacific benthic fauna of the Santa Maria Science. 29:341-348. Basin and Western Santa Barbara 13. ROE, P., and R. GIBSON. 1970. The Channel. Vol. 4. J. A. Blake, B. Hilbig, Nutrition of Paranemertes peregrina and P. H. Scott (eds.). Santa Barbara (Rhynchocoela: Hoplonemertea). Museum of Natural History, Santa Biological Bulletin. 139:80-91. Barbara, CA. 14. SMITH, R. I. 1959. The synonymy of 8. JOHNSON, M. W. 1943. Studies on the viviparous polychaete Neanthes the life history of the marine annelid lighti Hartman (1938) with Nereis Nereis vexillosa. Biological Bulletin. limnicola Johnson (1903). Pacific 84:106-14. Science. 13:349-350. 9. KOZLOFF, E. N. 1993. Seashore life 15. WILSON, W. H. 1980. A Laboratory of the northern Pacific coast: an investigation of the effect of a illustrated guide to northern California, terebellid polychaete on the Oregon, Washington, and British survivorship of nereid polychaete Columbia. University of Washington larvae. Journal of Experimental Marine Press, Seattle, WA. Biology and Ecology. 46:73-80. 10. PETTIBONE, M. 1963. Aphroditidae 16. WOODIN, S. A., S. M. LINDSAY, and through Trochochaetidae. In: Marine D. S. WETHEY. 1995. Process- polychaete worms of the New England specific recruitment cues in marine Region. Vol. 1. Smithsonian Institution, sedimentary systems. Biological Washington, D.C. Bulletin. 189:49-58.