Phylum:

Nucella ostrina Class: , Prosobranchia Order: The rock-dwelling emarginated dogwinkle Family: Thaisidae

Taxonomy: was previously called Sutures: Not deep (Fig. 1). Thais. Thais is now reserved for subtropical Anterior (Siphonal) Canal: Short: less than and tropical . For a more detailed 1/4 aperture length: species ostrina (Kozloff review of gastropod , see Keen and 1974) (Fig. 1); canal narrow, slot-like, not Coan (1974) and McLean (2007). Nucella. spout-like; not separated from large whorl by ostrina has mistakenly been called N. revolving groove. emarginata though it has now been found that Aperture: Wide; length more than 1/2 shell the two species diverged in the late length (Oldroyd 1924). Ovate in outline, with a Pleistocene epoch (Marko et al. 2003) short anterior canal but no posterior notch (Fig. 1). Description Umbilicus: Closed (McLean 2007). Size: Rarely over 30 mm (Kozloff 1974), : Dark brown with nucleus on one usually up to 20 mm (Puget Sound); up to 40 side (Fig. 2). mm, but rarely over 30 mm (California) Eggs: Pale yellow, vase-shaped, about 6 (Abbott and Haderlie 1980); illustrated mm high, in clusters of up to 300 capsules specimen (Coos Bay) 20 mm. Females (Abbott and Haderlie 1980) (Fig. 4). Each slightly larger than males (average 18.9 and capsule with 500-600 eggs. Each capsule 17.8) (Houston 1971). with a longitudinal suture and a hard clear Color: Exterior brown and dingy white, dirty escape aperture. gray, yellow or almost black (if diet of Veliger: Four distinct stages: advanced shell ); yellow, black or gray periostracum measures 775µ long (LeBoeuf 1971) (Fig. 5). in grooves between ridges; ridges sometimes white (black in this specimen). Interior: Possible Misidentifications aperture and chestnut brown or Snails of the Nucella can be purple. distinguished from other carnivorous Shell Shape: Fusiform; short , estuarine gastropods by their sculpture (the expanded whorl. Shell thin, not heavy. 3-4 same on both spire and whorls), by the large whorls; nuclear whorl inconspicuous. body whorl and by the large ovate aperture. Sculpture: Spire relatively high, partial nub Other genera with a siphonal notch, and of aperture lacking (McLean 2007); generally fusiform shape include: alternating large and small spiral ridges over Olivella and , which have most of shell, can be nodulose; sometimes columellar folds; ridges are obscure and surface is fairly Ocenebra and Ceratostoma which have a smooth. Axial sculpture wrinkled, not spout-like , not a narrow-slot- prominent. like one as in Nucella; Outer : Thin, crenulate, not thick and reticulata and dirum layered (Oldroyd 1924). No denticles or anal which have a distinct revolving furrow or fossa notch on posterior (upper) end, no single setting off the anterior canal from the body strong tooth near anterior canal. No row(s) or denticles within lip. whorl; (Lirabuccinum has spiral sculpture only Columella: Sunken and concave, arched and on the body whorl; the spire has both spiral flattened below: species ostrina; no folds, and axial ribs); (Fig. 1).

Bering, N., T. Hext and E. Parker. 2017. . 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.

A publication of the University of Oregon Libraries and the Oregon Institute of Marine Biology Individual species: http://hdl.handle.net/1794/12914 and full 3rd edition: http://hdl.handle.net/1794/18839 Email corrections to: [email protected] Acanthina (also from the family Thaisidae), they are morphologically cryptic. See Marko which has a strong tooth on the anterior end et al. (2003) for a more detailed discussion. of the outer lip. There are three other species of Nucella in Ecological Information our area. Two are not typically found in Range: Bering Sea south to northern Baja estuarine conditions, but they do look quite a California, but rare below Pt. Conception bit like N. ostrina: (Abbott and Haderlie 1980). , the file dogwinkle, is subtidal, Local Distribution: Coos Bay: marine short-spired, and fairly rare. It is whitish to portions, i.e. near bay mouth up to Fossil brown, with about 15 alternating large and Point. small file-like spiral ridges on the large whorl. Habitat: Almost entirely on rocky shores; in It can be up to 43 mm, somewhat larger than fairly heavy surf (Ricketts and Calvin 1971); N. ostrina. also in semi-protected areas (Houston 1971). , the channeled Outer shores in beds, on jetties. dogwhelk, has a high spire and a prominent Salinity: Full seawater; collected at 30. shoulder below the deep suture. It is light Temperature: Cold to temperate waters: (white to orange), and sometimes banded. Its small high in tidal range show great 14-16 spiral ridges are very evenly shaped thermal resistance, active at range of 0-30°C and spaced. It is an inhabitant of outer shore (Bertness and Schneider 1976). mussel beds. Larger than N. ostrina, it Tidal Level: Ubiquitous intertidal predators, averages 26.5 mm (male) and 24.8 mm found from mid to high intertidal zones (Moran (female) (California) (Houston 1971). and Emlet 2001). The third species, (see Associates: Primary prey is , description in this guide), is the most common especially Balanus; mussel Mytilus; Pisaster dogwinkle in the northwest, quite common in ochraceus. Commensal flatworm Nexilis bays and estuaries, and one of its many epichitonius found in specimens on Coos Bay variations is very like N. ostrina. N. lamellosa entrance jetty (Holliman and Hand 1962). can have strong axial ruffles, be quite smooth, Weight: 1.5 gm (wet). or have strong horizontal ribs. In this last Abundance: Common to abundant (McLean case, it is difficult to distinguish from N. 2007); much less common in inner bay than ostrina. N. lamellosa has a higher spire N. lamellosa (Coos Bay). (usually 5-7 whorls, including the tiny nuclear whorl); it is heavy, with a thick-layered lip, not Life History Information a thin crenulated one. There is usually at least Reproduction: Found to spawn year-round in one row of denticles inside the lip in N. Bodega Bay, Calif. and throughout Oregon, lamellosa; its anterior canal is longer than that but most activity is in November-February. of N. ostrina (more than 1/4 aperture length). Little hermaphroditism (Houston 1971). While N. lamellosa can have strong spiral Spawning is not salinity, photoperiod or ridges, the body whorl in this species is then temperature-related (Houston 1971). Females often flattened and angled, not expanded as gregarious (groups to 20), deposit egg in N. ostrina, and the horizontal ridges capsules in clusters. Each female lays 8-9 themselves are not alternating large and capsules; stalked capsules have about 200- small (compare Fig. 2, N. lamellosa in this 300 eggs each (ibid), many of which may be guide)