Eteone Lighti Order: Phyllodocida, Phyllodociformia
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Phylum: Annelida Class: Polychaeta, Errantia Eteone lighti Order: Phyllodocida, Phyllodociformia A paddleworm Family: Phyllodocidae, Eteoninae Taxonomy: The genus Eteone was revised tentacular cirri (Fig. 2). into three genera (Eteone, Hypereteone, Parapodia: Uniramous with neuropodia only. Mysta) by Wilson (1988) based on anal cirri All but first segment with a flat triangular dor- morphology and the presence and location sal cirrus, about as wide as long (Fig. 3), of proboscis papillae. Thus, E. lighti is these become longer and narrower posterior- sometimes referred to as Hypereteone lighti. ly. The ventral cirrus has a broad base taper- While the presence of three major groups ing to a blunt tip and is shorter than the neu- are apparent, splitting Eteone into these ropodial lobe (Fig. 3). Note: parapodium genera has not been recognized by most should be examined in side view to check for authors and E. lighti is the name most com- flatness, inflatedness, etc. monly seen (Pleijel 1991; Blake 1992; Blake Setae (chaetae): Setae are compound 1997; Blake and Ruff 2007). (Phyllodocidae, Blake 1975b) and consist of long, fine, colorless spinigers (Hartman 1968) Description (Figs. 4a,b). Size: Individuals to 30 mm in length and 1– Eyes/Eyespots: Two eyespots are present 1.5 mm in width (Hartman 1968). A 25-mm on posterior third of the prostomium (Fig. 2a). long Coos Bay specimen weighed 0.17 g Anterior Appendages: Prostomium bears (wet weight, Baker et al. 1970). two pairs of short, conical antennae and ap- Color: Pale or white, deep yellow dorsal pendages on the first segment include two transverse stripes (Hartman 1968) and dor- pairs of short and slender tentacular cirri sal cirri with deep yellow tips. (Eteone) (Fig. 2a). General Morphology: Body long and slen- Branchiae: der that gradually tapers posteriorly in the Burrow/Tube: illustrated specimen (Fig. 1) and is recog- Pharynx: Pharynx bears proboscis that can nizable by trapezoidal prostomium and trian- be smooth or wrinkled, but lacks papillae gular dorsal cirri (Blake and Ruff 2007). (Hartman 1968) (Fig. 1). Body: 75-100 total body segments (Fig. 1) Genitalia: where first segment incomplete dorsally Nephridia: (Eteone) and expands into tentacular cirri (Fig. 2a). Possible Misidentifications Anterior: Prostomium wider than Phyllodocids can have flattened, glob- long and with a median longitudinal groove ular, leaf- or paddle-like parapodial cirri (Fig. 2a). Anterior bears several paired (Blake 1975b). The family Phyllodocidae is appendages (see Anterior appendages) characterized by individuals that are long and but no nuchal papilla. slender and a prostomium that usually bears Trunk: four antennae (and occasionally a medial Posterior: A single pair of cirriform one). Additionally, they have 2–4 pairs of anal cirri are attached laterally (Figs. 1, 5) tentacular cirri, uniramous parapodia and and are approximately twice as large as compound setae. Other polychaete families 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. 2014. Eteone lighti. 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. with similar morphology are Syllidae and Ruff 2007). E. balboaensis is a rare and Nereidae, although neither has uniramous eyeless species from southern California parapodia. Phyllodocid genera are differ- (Hartman 1936). E. longa, found in the Pu- entiable by a “tentacular formula” which get Sound literature, but not in guides from combines important taxonomic characters California and Oregon (Blake and Ruff 2007), including the arrangement of tentacular cir- has a long, symmetrical conical dorsal cirrus, ri, the fusion of tentaculate segments and and a ventral cirrus almost as long as the pa- the occurrence of setae on those segments rapodial lobe; its anal cirri are broad and (Blake and Ruff 2007). The genus Eteone spheroidal (Banse and Hobson 1974; Kozloff has only two pairs of short tentacular cirri 1974). and short prostomial antennae (Fauchald Ecological Information 1977) (Fig. 2a). Range: Type locality is San Francisco Bay, The species most similar to E. lighti California. Known range includes central and in our area is E. pacifica, which has no (or southern California extending into Oregon, but inconspicuous) eyes, a prostomium longer probably not to Washington (Hartman 1968; than wide, flat broadly rounded asymmetri- Blake and Ruff 2007). cal dorsal cirri and irregularly spaced black Local Distribution: Coos Bay sites include spots on its yellowish body. Individuals are South Slough, particularly northern sites large and can be more than 100 mm in len- (Porch 1970). gth (Blake and Ruff 2007). A variety, E. p. Habitat: Mudflats, preferring muddy sand (in spetsbergensis, has parapodial setae with Coos Bay, Porch 1970; Blake and Ruff 2007). two large, equal teeth at the end of the Salinity: Collected in Coos Bay in South shaft (E. pacifica sensu stricto has setae Slough at salinities ranging from 20–30 with two unequal teeth at the end of the (Baker et al 1970). shaft) (Banse and Hobson 1974). Temperature: Other species of Eteone include E. cali- Tidal Level: fornica, which also has a broad truncate Associates: Common amongst eelgrass. prostomium, but has a nuchal papilla be- Abundance: E. lighti can be one of the most tween its dark red eyes, and wide, dorsal common and widespread mudflat worms in parapodial cirri. Its ventral cirri are very the upper Coos Bay. Specifically in South short in the posterior parapodia, it has small Slough, abundances were measured at up to brown pigment spots on its body (Banse several hundred individuals/m2 (Porch 1970). and Hobson 1974), which comprises 80-95 total segments. E. californica is slightly Life-History Information smaller than E. lighti at 20 mm in length, on Reproduction: Many benthic polychaetes, average, and the setae in E. californica including phyllodocids, can reproduce via have a pair of large teeth with 4–5 denticles epitoky, where all or a portion of the worm on shaft tip (Blake 1997). E. dilatae is a transforms into a pelagic form (called an long, slender worm with up to 250 seg- epitoke) that releases gametes (Pleijel and ments and is found on sandy beaches of Rouse 2006). Reproductive modes among the outer coasts in central and southern phyllodocids range from broadcast spawning California (Hartman 1936; Blake and Ruff to internal fertilization or pseudocopulation 2007). E. dilatae is pale green in body co- where females deposit eggs into gelatinous lor and characterized by a long prostomium benthic masses. Although the reproduction and sub-rectangular dorsal cirri (Blake and and development of E. lighti is not known, E. 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] viridis females deposit eggs (100 µm in di- Smith, and J. T. Carlton (eds.). University ameter) into gelatinous masses under rocks of California Press, Berkeley. and amongst algae, but this has not been 4. —. 1975b. The Larval development of pol- observed in E. longa (eggs 80 µm in ychaeta from the northern California diameter) (Fernald et al. 1987; Crumrine Coast. III. Eighteen species of Errantia. 2001). Ophelia. 14:23-84. Larva: The development of other known 5. —. 1992. New species and records of Eteone species proceeds through trocho- Phyllodocidae (Polychaeta) from the conti- phore and nectochaete stages where ad- nental shelf and slope off California. Pro- vanced larvae are large and predatory and ceedings of the Biological Society of usually collected near the bottom of plankton Washington. 105:693-708. samples (Lacalli 1981; Fernald et al. 1987; 6. —. 1997. Family Phyllodocidae, p. 109- Crumrine 2001). Of the local Eteone spe- 178. In: Taxonomic atlas of the benthic cies, only the larvae of E. longa are known fauna of the Santa Maria Basin and the and can be identified from plankton samples Western Santa Barbara Channel. Vol. 4. J. (Thorson 1946; Blake 1975a; Crumrine A. Blake, B. Hilbig, and P. H. Scott (eds.). 2001). Santa Barbara Museum of Natural History, Juvenile: Sexual maturity in another Eteone Santa Barbara, CA. species, E. longa, is reached at 20–30 mm 7. BLAKE, J. A., and E. R. RUFF. 2007. Pol- in length (females reaching maturity at long- ychaeta, p. 309-410. In: Light and Smith er lengths) (Rasmussen 1956 in Fernald et manual: intertidal invertebrates from cen- al. 1987). tral California to Oregon. J. Carlton (ed.). Longevity: University of California Press, Berkeley, Growth Rate: CA. Food: 8. CRUMRINE, L. 2001. Polychaeta, p. 39- Predators: In Tillamook Bay, predators of 77. In: Identification guide to larval marine Eteone species include Hypomesus pre- invertebrates of the Pacific Northwest. A. tiosus (surf smelt) in the lower bay and Pa- Shanks (ed.). Oregon State University rophrys vetulus (English Sole) in mid-bay Press, Corvallis, OR. (Forsberg et al 1977). 9. FAUCHALD, K. 1977. The polychaete Behavior: E. lighti swim by utilizing their worms: definitions and keys to the orders, paddle-shaped parapodia. families, and genera. Natural History Mu- seum of Los Angeles County Science Se- Bibliography ries. 28:1-190. 1. BAKER, D., R. RUTOWSKI, and A. 10. FERNALD, R. L., C. O. HERMANS, T. C. TALLMAN. 1970. Coos Bay Estuary LACALLI, W. H. WILSON, JR, and S. A. Study Area B-4, B-5. WOODIN. 1987. Phylum Annelida, Class 2. BANSE, K., and K. D. HOBSON. 1974. Polychaeta, p. 138-195. In: Reproduction Benthic errantiate polychaetes of British and development of marine invertebrates Columbia and Washington.