Nereis Vexillosa Class: Polychaeta, Errantia

Phylum: Annelida

Nereis vexillosa Class: Polychaeta, Errantia

Order: Phyllodocida, Nereidiformia A large mussel worm Family: Nereididae, Nereidinae

Taxonomy: One may find several subjective third setiger (Hilbig 1997). Posterior notopo- synonyms for Nereis vexillosa, but none are dial lobes gradually change into long strap- widely used currently. like ligules (Fig. 6), with dorsal cirrus inserted terminally (most important species characte- Description ristic). The parapodia of epitokous individuals Size: Individuals living in gravel are larger are modified for swimming and are wide and than those on pilings and sizes range from plate-like (Kozloff 1993). 150–300 mm in length (Johnson 1943; Rick- Setae (chaetae): Notopodia bear ho- etts and Calvin 1971; Kozloff 1993) and up mogomph spinigers anteriorly (Fig. 8d) that to 12 mm in width (Hartman 1968). gradually transition to few short homogomph Epitokous adults are much larger than sex- falcigers posteriorly (Fig. 8a). Both anterior ually immature individuals. For example, and posterior neuropodia have homo- and one year old heteronereids were at least 560 heterogomph spinigers (Fig. 8c, d) and heter- mm in length (Johnson 1943). ogomph falcigers (Fig. 8b) (Nereis, Hilbig Color: Body color grey and iridescent green, 1997). Acicula, or heavy internal black blue and red body color. Females have spines, are found on all noto- and neuropodia more a reddish posterior than males (Kozloff (Figs. 6). 1993). Eyes/Eyespots: Two pairs of small ocelli are General Morphology: Thick worms that are present on the prostomium (Fig. 2). rather wide for their length (Fig. 1). Anterior Appendages: Prostomium bears Body: More than 100 body segments are two small antennae and two massive palps normal for this species (Hartman 1968), the each with small styles. Four pairs of tentacu- illustrated specimen has 105 segments (Fig. lar cirri are also present and the two dorsal 1). Nereids are recognizable by their anteri- pairs are longest (Fig. 2). or appendages including two prostomial Branchiae: Absent (Blake and Ruff 2007). palps and four peristomial tentacular cirri Burrow/Tube: Newly hatched animals build (see Anterior appendages) (Fig. 2) (Blake flimsy mucus and sand tubes (Johnson 1943). and Ruff 2007). Adult worm to tube length ratio is 1.65:1 (Roe Anterior: Prostomium pyriform and 1975). widest posteriorly (Fig 2). Pharynx: The pharynx bears a distinct eversi- Trunk: Thick segments that are wider ble proboscis. The everted proboscis has two than they are long, gently tapers to posterior rings, oral (or proximal) and distal (or maxil- (Fig. 1). lary) and terminates with two fang-shaped Posterior: Pygidium bears a posteri- jaws, with 6–8 teeth (Fig. 3, 4). The oral ring or cirrus with four, fine, accessory lobes is used largely in burrowing, while the distal (Fig. 1) that are often broken during collec- ring is used in feeding (Barnes and Head tion. 1977). Each ring is equipped with many pa- Parapodia: Parapodia are of typical nereid pillae and conical paragnaths and their pat- biramous structure (Figs. 5, 6, 7) from the

A publication of the University of Oregon Libraries and the Oregon Institute of Marine Biology Individual species: https://oimb.uoregon.edu/oregon-estuarine-invertebrates and full 3rd edition: http://hdl.handle.net/1794/18839 Email corrections to: [email protected]

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.

terns are taxonomically relevant. Parag- inconspicuous paragnaths on its proboscis naths (conical teeth) on both oral and maxil- (Hartman 1968). Nereis latescens is common lary rings are arranged as follows: Area I amongst algal holdfasts and their dorsum has several small cones in tandem; Area II bears transverse lines of brown pigment has an oblique, small transverse patch (Fig. (Blake and Ruff 2007). Nereis pelagica is an 3); Area III has a circular patch; Area IV intertidal to subtidal species with dark (paired) with an oblique patch of several parapodial lobes. The common and abundant rows, both are ventral; Area V has no Nereis vexillosa, can be differentiated from paragnaths; Area VI with a mass of 6–9 or the above species by its olive green to brown more and both are dorsal (Fig. 3); Areas VII color where it is found in many diverse marine and VIII both have continuous bands of environments, especially in mussel beds. many paragnaths, those anterior being larg- Furthermore, it has distinct greatly elongated, est and both are ventral (Fig. 4). strap-like notopodial lobes in the posterior Genitalia: parapodia. Nephridia: Other morphologically similar species include those in the genus Neanthes. Nean- Possible Misidentifications thes limnicola individuals are usually pale and The prostomia of nereid worms are translucent, not distinctly green as in N. quite alike, with four eyes, a pair of frontal vexillosa. Neanthes brandti has been at times antennae and biarticulate palps, and 3–4 considered a subspecies or a synonym of N. pairs of tentacular cirri. Common local nere- virens, (Breton et al. 2004) and is large, sand- ids are those in the genera Neanthes and dwelling and green in color like N. vexillosa. Nereis. Neanthes species have only ho- However, N. brandti is usually paler ventrally mogomph spinigerous setae in the posterior and, in contrast to N. vexillosa, it has many notopodia. The genus Neanthes is further teeth on all areas of the proboscis, its poste- distinguished by having only conical parag- rior parapodial lobes are leaf-like, not long naths on both proboscis rings, and biramous and strap-like. N. brandti also has no falcigers parapodia with composite setae (Hartman in the posterior notopodia and its ecological and Reish 1950). Neanthes have spiniger- niche is different, it does not live in mussel ous notosetae only (Hilbig 1997). The mor- beds or on pilings. Neanthes succinea is one phologically similar genus, Nereis sensu of the most common nereids in the Northeast stricto, is characterized by species with Pacific and has a very enlarged posterior no- spinigerous notosetae in the anterior half of topodial lobes, with a small distal dorsal cirrus the body and falcigerous notosetae attached at the end of the lobe (Blake and posteriorly (Smith 1959; Pettibone 1963). Ruff 2007). N. succinea is thought to be a mo- Common local Nereis species include re southern form (although it has been repor- 6–7 species (Blake and Ruff 2007). Nereis ted from Netarts Bay). eakini, from rocky habitats, that has a long prostomium and proboscis rings covered Ecological Information with small round paragnaths. The bright Range: Type localities are Alaska and Sibe- green Nereis grubei has greatly expanded ria. Known range includes eastern Siberia to posterior notopodial parapodial lobes and no Alaska and south to central California paragnaths in area V of the proboscis. (Hartman 1968). Nereis procera is subtidal in sand, has tiny Local Distribution: Coos Bay distribution in- eyes, a very long body, and unusually cludes many sites and, within Oregon, N. ve-

xillosa has also been found in Yaquina Bay. Larva: Larval development was described by Habitat: Individuals occur among heavy al- Johnson (1943). Pelagic and lecithotrophic gae cover, eelgrass, bark, and under rocks larvae hatch from the gelatinous egg mass or cobblestones. Their preferred substrate is between 3–5 setiger stages. Survivorship of sand or mud mixed with sand. N. vexillosa larvae is reduced due to ingestion by the co- also occurs in mussel beds and barnacle occuring terebellid polychaete Eupolymnia clusters on intertidal pilings along the open heterobranchia (Wilson 1980). When larvae coast (Blake and Ruff 2007). are 1–2 weeks old (4–6 setiger stages), they Salinity: Nereis vexillosa is strictly a marine build mucus tubes and begin to feed (Roe species. 1975; Fernald et al. 1987). Temperature: Cold water to temperate Juvenile: In the field, juveniles have 8–25 se- (Johnson 1943). tigers from 3–5 weeks, are one half adult size Tidal Level: Intertidal and shallow water after one year and are fully grown and sexual- (Johnson 1943). ly mature the following year (Roe 1975). Ju- Associates: Occurs with Neanthes virens, veniles can grow quickly in the lab, on a diet in mussel beds and with the scaleworm of other polychaetes (Johnson 1943). In the Halosydna, porcelain crab Petrolisthes, and field, they can be territorial two weeks after isopod Cirolana. hatching (Roe 1975). Researchers have Abundance: Ubiquitous (Ricketts and Cal- shown that N. vexillosa is less likely to burrow vin 1971). The most abundant large annelid into sediment that has been recently disturbed of the Pacific Northwest (Johnson 1943), but (e.g., by erosion, mixing, fresh feces, burrow varies in abundance throughout wide geo- trails and feeding tracks) (Woodin et al. 1995). graphical range (Ricketts and Calvin 1971). Longevity: Two-year life-span (Roe 1975). About 22 individuals/m2 were reported in Growth Rate: Varies greatly. At 4–12 Mitchell Bay, Washington (Roe 1975). months and 60 segments, adult species char- acteristics are conspicuous, including strap- Life-History Information like parapodial lobes (Johnson 1943). Reproduction: Nereis vexillosa has Food: N. vexillosa is omnivorous and prefers heteronereid a form (called an epitoke) fresh animal food, and will reject dead food. characterized by modified parapodia (Fig. This species is not a scavenger by preference 7). These epitokes swarm at night in (Johnson 1943). Nereids use their jaws to summer months (June in Coos Bay and tear apart and eat pieces of algae (Kozloff March-August in Washington, Fernald et al. 1993). Young build flimsy mucus and sand 1987). Males appear first near water's surfa- tubes, and rarely leave them completely to ce, then females. Large (200–250 µm in feed. diameter) oocytes are released from the fe- Predators: Sometimes preyed upon by ne- males in a gelatinous mass and both female mertean Paranemertes peregrina (Roe 1970). and egg mass sink to the benthos. Both Widely used by man for fish bait. adults usually die shortly thereafter (Fernald Behavior: Very active worm that can bite hu- et al. 1987). Eggs are found in a firm, man collector. irregular, gelatinous mass, 2.5–7.5 cm in diameter, translucent and blue green, green Bibliography or brown when freshly laid. Eggs can 1. BARNES, R. S. K., and S. M. HEAD. N. vexillosa withstand strong wave action. is 1977. Variation in paragnath number in the only nereid with a solid egg mass. some British populations of estuarine poly-

chaete Nereis diversicolor. Estuarine and WA. Coastal Marine Science. 5:771-781. 10. PETTIBONE, M. 1963. Aphroditidae 2. BLAKE, J. A., and R. E. RUFF. 2007. through Trochochaetidae. In: Marine poly- Polychaeta, p. 309-410. In: The Light chaete worms of the New England Region. and Smith manual: intertidal inverte- Vol. 1. Smithsonian Institution, Washing- brates from central California to Oregon. ton, D.C. J. T. Carlton (ed.). University of Califor- 11. RICKETTS, E. F., and J. CALVIN. 1971. nia Press, Berkeley, CA. Between Pacific tides. Stanford University 3. BRETON, S., F. DUFRESNE, G. Press, Stanford, California. DESROSIERS, and P. BLIER. 2004. 12. ROE, P. 1975. Aspects of life-history and Morphological variation in Nereis of territorial behavior in young individuals (Neanthes) virens (Polychaeta : Nerei- of Platynereis bicanaliculata and Nereis didae) populations. Journal of the Marine vexillosa (Annelida: Polychaeta). Pacific Biological Association of the United King- Science. 29:341-348. dom. 84:983-985. 13. ROE, P., and R. GIBSON. 1970. The Nu- 4. FERNALD, R. L., C. O. HERMANS, T. C. trition of Paranemertes peregrina LACALLI, W. H. WILSON, JR, and S. A. (Rhynchocoela: Hoplonemertea). Biologi- WOODIN. 1987. Phylum Annelida, Class cal Bulletin. 139:80-91. Polychaeta, p. 138-195. In: Reproduction 14. SMITH, R. I. 1959. The synonymy of the and development of marine invertebrates viviparous polychaete Neanthes lighti of the northern Pacific coast. M. F. Hartman (1938) with Nereis limnicola Strathmann (ed.). University of Washing- Johnson (1903). Pacific Science. 13:349- ton Press, Seattle, WA. 350. 5. HARTMAN, O. 1968. Atlas of the erranti- 15. WILSON, W. H. 1980. A Laboratory inves- ate polychaetous annelids from Califor- tigation of the effect of a terebellid poly- nia. Allan Hancock Foundation, Universi- chaete on the survivorship of nereid poly- ty of Southern California, Los Angeles. chaete larvae. Journal of Experimental 6. HARTMAN, O., and D. J. REISH. 1950. Marine Biology and Ecology. 46:73-80. The Marine annelids of Oregon. Oregon 16. WOODIN, S. A., S. M. LINDSAY, and D. State College, Corvallis, Oregon. S. WETHEY. 1995. Process-specific re- 7. HILBIG, B. 1997. Family Nereididae, p. cruitment cues in marine sedimentary sys- 291-316. In: Taxonomic atlas of the ben- tems. Biological Bulletin. 189:49-58. thic fauna of the Santa Maria Basin and Western Santa Barbara Channel. Vol. 4. Updated 2015 J. A. Blake, B. Hilbig, and P. H. Scott T.C. Hiebert (eds.). Santa Barbara Museum of Natural History, Santa Barbara, CA. 8. JOHNSON, M. W. 1943. Studies on the life history of the marine annelid Nereis vexillosa. Biological Bulletin. 84:106-14. 9. KOZLOFF, E. N. 1993. Seashore life of the northern Pacific coast: an illustrated guide to northern California, Oregon, Washington, and British Columbia. Uni- versity of Washington Press, Seattle,