Carinoma Mutabilis Phylum: Nemertea Class: Anopla Order: Paleonemertea a Ribbon Worm Family: Carinomidae

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Carinoma mutabilis Phylum: Nemertea Class: Anopla Order: Paleonemertea A ribbon worm Family: Carinomidae

Taxonomy: Originally described as cephalic grooves (order Carinoma griffini by Griffin (1898), this Paleonemertea). species was re-described by Coe (1904) as Trunk: Carinoma mutabilis. Initially, two varieties Posterior: No caudal cirrus. were described (C. mutabilis argillina and C. Eyes/Eyespots: No ocelli. mutabilis vasculosa) based on size and degree of muscle development but these Mouth: Just behind brain (class Anopla). differences were determined to be Proboscis: Eversible (phylum Nemertea) intraspecific variation (Gibson 1995). and, when not everted, coiled inside rhynchocoel (cavity). No stylets and Description proboscis pore (opening to rhynchocoel) Size: Great size variation is reported for this almost terminal. species, from 2.5 to 50 cm, although few are Tube/Burrow: Individuals are commonly over 20 cm on the California coast. The surrounded by thin sandy mucous tube and largest width is 3–5 mm with average sizes worms are happiest in the lab if allowed to much less (Coe 1901, 1905; Kozloff 1974). burrow in sand. Specimens are approximately 14 cm in length and 1 mm in width when preserved (Griffin Possible Misidentifications 1898). The Genus Carinoma is small and Color: Homogeneous (no variation dorso- comprises seven described species ventrally). Anterior and head milk white, not worldwide including (Gibson 1995): C. translucent, sometimes with brownish mottling patagonia, intertidal from southern Chile (Coe 1901). Intestinal region cream or (Magellan Straits); C. patriciae, an Australian brownish where internal organs show as species found in silty sand, mud and shell transverse dark lines. Males dark yellow or mix; C. tremaphoros, intertidal and sublittoral orange, females reddish (Griffin 1898; Kozloff in sand and mud from the Atlantic and Gulf 1974) (Fig. 1). Posterior-most region white coasts; C. hamanako occurs in sand and (Griffin 1898). mudflats near Honshu, Japan (Kajihara et al. General Morphology: Soft, elongate (but not 2011); C. armandi occurs in the low intertidal stretchy) non-segmented (phylum Nemertea). and is found among polychaete tubes in the Body: Thickened and rounded anteriorly, British Isles; C. crabica from the Venezuelan slightly compressed dorso-ventrally from coast in Curaçao (Gibson 1995). behind head and very flattened posteriorly C. mutabilis is believed to be the (Fig. 1). Individuals tend to coil from the sides only carinomid species on the Pacific coast, posteriorly (Coe 1905). but research suggests that there are likely Anterior: Anterior shape changes at least four other species in the genus constantly and can be rounded or Carinoma in Coos Bay, alone (2008-2014, T. elongate. Head is wider than neck Hiebert and S. Maslakova, unpublished). and not distinctly marked from the Differentiating these five species based on body (Coe 1901). When crawling, morphology alone is currently very head is narrower than body with slight challenging. One local heteronemertean, narrowing at neck (Griffin 1898). No which might cause confusion is Baseodiscus punnetti which has many very

A publication of the University of Oregon Libraries and the Oregon Institute of Marine Biology Individual species: http://hdl.handle.net/1794/12647 and full 3rd edition: http://hdl.handle.net/1794/18839 Email corrections to: [email protected] minute eyespots, and slight, oblique mutabilis larvae from ripe adults collected in cephalic grooves. Although both species January and February (Friday Harbor, WA) flatten posteriorly, they can be differentiated have been reared in the lab and the from one another by the fact that B. punnetti development of their protonephridia can retract its head and Carinoma cannot. documented (Bartolomaeus et al. 2014). Other palaeonemerteans that are Larva: Planktonic larvae of C. tremaphorus superficially similar to C. mutabilis are are uniformly ciliated, possess both apical tuft Carinomella lactea and Tubulanus and posterior cirrus and are 150 µm in length pellucidus. They by possess lateral or (Coe 1943; Maslakova et al. 2004a, 2004b). cerebral sensory organs (Roe et al. 2007). Larvae of the genus Carinoma are distinct in It is sometimes very difficult to having a single, mid-ventral eye that is distinguish among nemerteans without anterior to the mouth (Norenburg and Stricker dissecting them because many 2002; Maslakova et al. 2004a, 2004b; identifying characteristics are internal Bartolomaeus et al. 2014). and not visible. Ways in which the Juvenile: worms flatten, contract, and coil are Longevity: useful as aids to identification of live Growth Rate: specimens. Food: A predator, C. mutabilis captures prey with its sticky, eversible proboscis. Ecological Information Predators: Range: Described by Griffin from specimens Behavior: collected in Puget Sound, Washington (Griffin 1898). Known range includes the pacific Bibliography coast of North America, from British Columbia to Gulf of California (Gibson 1995). 1. BARTOLOMAEUS, T., S. Local Distribution: Coos Bay sites include MASLAKOVA, and J. VON DOHREN. South Slough, Pony Slough and North Spit. 2014. Protonephridia in the larvae of Habitat: Most commonly encountered in the paleonemertean species Carinoma sand and sandy mud. Also found in clay mutabilis (Carinomidae, Nemertea) (Haderlie 1975) and amongst wharf pilings and Cephalothrix (Procephalothrix) (Griffin 1898). filiformis (Cephalothricidae, Salinity: Estuarine. Nemertea). Zoomorphology. 133:43- Temperature: Latitudinal range would 57. indicate a wide temperature tolerance. 2. COE, W. R. 1901. Papers from the Tidal Level: Intertidal and below (to 40 m) Harriman Alaska Expedition xx. The (Corrêa 1964). Nemerteans. Proceedings of the Associates: Washington Academy. iii:pp. 1-110. Abundance: Regularly encountered in South 3. COE, W. R. 1905. Nemerteans of the Slough, common in San Pedro Harbor, west and northwest coasts of America. California but less abundant in San Diego, Museum of Comparative Zoology, California (Coe 1905). Cambridge, MA. 4. —. 1943. Biology of the nemerteans of Life-History Information the Atlantic coast of North America. Reproduction: Sexually mature in August Transactions of the Connecticut (California and Puget Sound, Coe 1901, Academy of Arts and Sciences. 1905). Dioecious (separate sexes), with many 35:129-328. gametes released at once. Fertilization occurs 5. CORRÊA, D. D. 1964. Nemerteans in the water column. Development has been from California and Oregon. described for C. tremaphorus where eggs are Proceedings of the California 90–110 µm and surrounded by a chorion Academy of Sciences (series 4). (Maslakova et al. 2004a, 2004b). Carinoma 31:515-558.

Hiebert, T.C. 2015. Carinoma mutabilis. 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. 6. GIBSON, R. 1995. Nemertean genera and species of the world: an annotated checklist of original names and description citation, synonyms, current taxonomic status, habitats and recorded zoogeographic distribution. Journal of Natural History. 29:271-562. 7. GRIFFIN, B. B. 1898. Description of some marine nemerteans of Puget Sound and Alaska. Annals of the New York Academy of Sciences. xi:pp. 193- 218. 8. HADERLIE, E. C. 1975. Phylum Nemertea (Rhynchocoela), p. 112- 120. In: Light's manual; intertidal invertebrates of the central California coast. S. F. Light, R. I. Smith, and J. T. Carlton (eds.). University of California Press, Berkeley. 9. KAJIHARA, H., H. YAMASAKI, and S. ANDRADE. 2011. Carinoma hamanako sp. nov.(Nemertea: Palaeonemertea), the first representative of the genus from the northwest Pacific. Species Diversity. 16:149-165. 10. KOZLOFF, E. N. 1974. Keys to the marine invertebrates of Puget Sound, the San Juan Archipelago, and adjacent Regions. University of Washington Press, Seattle. 11. MASLAKOVA, S., and J. NORENBURG. 2001. Trochophore larva is plesiomorphic for nemerteans: evidence for prototroch in a basal nemertean Carinoma tremaphoros (Phylum Nemertea, Palaeonemertea). American Zoologist. 41: 1515-1516. 12. MASLAKOVA, S. A., M. Q. MARTINDALE, and J. L. NORENBURG. 2004. Vestigial prototroch in a basal nemertean, Carinoma tremaphoros (Nemertea; Palaeonemertea). Evolution & Development. 6:219-226. 13. ROE, P., J. L. NORENBURG, and S. MASLAKOVA. 2007. Nemertea, p. 221-233. In: Light and Smith manual: intertidal invertebrates from central California to Oregon. J. Carlton (ed.). University of California Press, Berkeley, CA.