Tegula Funebralis Class: Gastropoda, Vetigastropoda
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Phylum: Mollusca Tegula funebralis Class: Gastropoda, Vetigastropoda Order: Trochida The black turban or top shell snail Family: Trochoidea, Tegulidae Description without sculpture (fig. 3). Size: to 50 mm or more high (Carlton and Operculum: thin; round, numerous Roth 1975), usually less than 25 mm (Keep spiral lines; horny, not calcareous (fig. 4). 1935); this specimen 20 mm diameter, 17 Body: mm high. Radula: with a single central tooth; 5-7 Color: exterior purplish-black, not shiny; pointed lateral teeth, 8-10 marginal teeth (fig. with white eroded apex. Gray when dry. In- 6). terior white with a black margin; a pearly or Foot: long, relatively narrow; with "rainbow" deep interior patch. White around epipodal tentacles along sides: family Tro- columella (McLean 1969) (fig. 1) chidae (4 on each side: species funebralis Shell: (fig. 5). Shape: strong; 4 inflated whorls; ra- Possible Misidentifications ther top-shaped, (conical) with a flat base; The Trochidae are herbivorous, conical round aperture, nearly round, horny opercu- snails, pearly within, with round, entire aper- lum: family Trochidae (Griffith 1975). Small tures and thin horny circular opercula (Griffith snails are about as high as wide (figs. 1, 2); 1975). The Turbinidae, a similar family, are older ones become higher than wide (Frank also conical, but they have a calcareous oper- 1965b). culum, and are represented here only by Sculpture: below the suture is an im- Astraea, a large subtidal and offshore spe- pressed line (Oldroyd 1924), or a scaly band cies. (Carlton and Roth 1975): "foliaceous incre- The other common genus of the Tro- mental lamellae" (Oldroyd 1924) (figs. 1. 2). chidae is Calliostoma, a conical top shell, Whorls "spirally lirate," i.e. having up to 17 which is distinguished from Chlorostoma thread-like spiral lines (figs. 1, 2); sometimes chiefly by its lack of denticles or nodes on the smooth except for base, or strongly sculp- columella. Its whorls are not inflated like tured above (fig. 2). Chlorostoma's. Calliostoma is found on the Columella: spirally twisted (Oldroyd outer shores, not in bays; it has many spiral 1924), with 2 denticles (nodes) near base ribs, no umbilicus, and various distinctive col- (fig. 3), lower node worn or indistinct. orations. Umbilicus: covered by a callus, Snails of the genus Chlorostoma have nearly always closed (Carlton and Roth strong columellar nodes, a round, thin, horny 1975) (fig. 3). Specimens with an open um- operculum with many spiral lines, and a bilicus do not have a flange between umbili- pearly interior. They sometimes have a peri- cus and aperture. ostracum. The 3 other species of Chlorosto- Aperture: round, complete; no anteri- ma found on the Pacific coast are not known or notch or canal (fig. 3): aperture length 3 to be estuarine: less than /4 shell length. Tegula montereyi probably does not Outer Lip: smooth, black-rimmed, 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] Tegula funebralis Unknown. 1979. Tegula funebralis. In: Oregon Estuarine Invertebrates: Rudys' Illustrated Guide to 140 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. occur above Bolinas Bay, north of San Fran- marine portions of estuaries in rocky situa- cisco; it occupies the low intertidal off-shore tions amongst seaweed (Griffith 1975). zone, often in kelp beds. This species is Strongly built: can withstand surf. Females brown, with a strong, open umbilicus and a found in more exposed places than males at strictly conical (not inflated) profile. low tide (Frank 1975). Species is negatively Tegula pulligo, the dusky turban, oc- phototactic: seeks the light (Morris et al 1980). curs in the low intertidal in California; it is the Salinity: collected at 30 ‰ salt. Cannot with- dominant Tegula in Puget Sound (Griffith stand continued exposure to low salinity. 1975), where it occurs in open coasts and in Temperature: found in temperate waters on- protected situations (Kozloff 1974a). T. pulli- ly. With black color can get quite warm during go has an open umbilicus with the inner lip exposure to sun at low tides. produced into a flange (it is closed in T. fu- Tidal Level: on outer shores, most common nebralis). It has a brown (not purple or at high inter-tidal (2-0 m) (Frank 1975); found black) periostracum; its basic color is brown in midintertidal as well." In estuary found at 0- or gray, sometimes with orange, white or +1 ft. Small snails settle high, live there 5-6 brown spots on the edge. Its habitat is open years, then migrate to lower levels (to +0.6- - rocky beaches (Griffith 1975). 0.2 m) (Paine 1979). Chlorostoma brunnea, the brown tur- Associates: on outer coast: slipper shell ban, is the closest to C. funebralis in Ore- Crepidula and several limpets (Collisella), gon; it does not seem to occur in Puget which can be predatory. Empty shells used by Sound (Kozloff 1974a), and is very common hermit crabs. on the outer shores in Oregon and around Abundance: most abundant mid-intertidal San Francisco (Packard 1918). It has only grazer (Frank 1975). one node on the columella, as opposed to Weight: this specimen 4g wet, with shell. C. funebralis' two; its shell is brown or or- Life-History Information ange brown, and it lacks the scaly subsutur- Reproduction: dioecious; eggs and sperm al band of funebralis (Carlton and Roth exuded into water. Sexes can be determined 1975). C. brunnea is found lower in the inter- by color of foot sole: males are light, females tidal than funebralis, or in off-shore kelp darker; female gonad bright green from egg beds near the surface; probably never in es- yolk. Egg masses gelatinous, about 3 mm di- tuaries. ameter; several hundred eggs, about 0.19 Tegula gallina, the speckled tegula, is mm diameter. Breeding probably once a year gray to green, lacks the scaly subsutural (Paine 1979); reproductive size of snails 14 band, and is found south of Santa Barbara. mm (Paine 1971). Planktonic veliger larvae It is closely related to C. funebralis; the radu- emerge on 7th day, settle 12th day. Long life of lae are quite similar (Merriman 1967). T. funebralis ensures increased lifetime repro- Ecological Information ductive effort (Frank 1975). Range: Vancouver, B.C., to central Baja Larva: California (McLean 1969). Juvenile: Local Distribution: marine portions of large Longevity: lives up to 30 years; average age Oregon. estuaries; Coos Bay: Pigeon Point. may be 10 years (Frank 1975). Habitat: avoids exposed outer coast situa- Growth Rate: young snails grow rapidly: from tions although it is found in rocky protected 4-5.6 mm and 27 mg average weight (June) outer tidepools (Carlton and Roth 1975); to 5.6-9.8 mm. 177.3 mg (following March) 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] (Morris et al 1980). California snails do not Tegula funebralis. Growth. 29:395-403. show growth rings of Oregon snails, which in 4. ——. 1975. Latitudinal variation in the life older animals reveal an annual winter cessa- history features of Tegula funebralis tion of growth (Frank 1975). (Prosobranchia: Trochidae). Marine Biolo- Food: “a catholic feeder" (Frank 1975): al- gy. 31:181-192. most any common alga. Prefers Macrocystis 5. FRITCHMAN, H. K. 1965. The radulae of integrifolia, Nereocystis luetkeana, Rhodo- Tegula species from the west coast of glossum affine, Gigartina canaliculata: i.e. North America and suggested intrageneric fleshy forms. If not available, will eat en- relationship. The Veliger. 8:11-14. crusting green alga, Ralfsia pacifica, detritus 6. GRIFFITH, L. M. 1975. The intertidal uni- (Abbott et al 1964). valves of Britsh Columbia. British Columbi- Predators: Pisaster ochraceus in low inter- an Provincial Museum Handbook. 26:1- tidal. Although Chlorostoma is not its pre- 101. ferred prey, Pisaster can consume over ¼ 7. KEEP, J., J. Longstreth (eds). 1935. West the available snails (Frank 1965b). Possi- coast shells; a description in familiar terms bly limpet Collisella; carnivorous snail Nucel- of principal marine, fresh-water, and land la; crab Cancer antennarius. mollusks of the United States, British Co- Behavior: larger animals migrate to lower lumbia, and Alaska, found west of the Si- intertidal. Species is sedentary, aggregates erra. Calif., Stanford University Press; at low tide, moves up to rock tops at London, H. Milford, Oxford University nighttime high tides (not diurnal ones) Press, Stanford University. (Morris et al 1980). Territory: tends to live in 8. KOZLOFF, E. N. 1974a. Keys to the ma- a radius of about 1.5 m for months; a daily rine invertebrates of Puget Sound, the San movement of about 1m (Frank 1975). Snails Juan Archipelago, and adjacent regions. move well on rocks, are clumsy on sand. University of Washington Press, Seattle & They place pebbles on the foot to alter bal- London. ance (Morris et al 1980). Escape predators 9. MCLEAN, J. H. 1969. Marine shells of by sensory perception (seastars), or by southern California. [Los Angeles] Los An- crawling onto top of predator's shell geles County Museum of Natural History. (carnivorous snails). 10. MERRIMAN, J. A. 1967. Systematic impli- cations of radular structures of west cost Bibliography species of Tegula. The Veliger. 9:399-403. 1. ABBOTT, D. P., L. R. BLINKS, J. H. 11. MORRIS, R. H., D. P. ABBOTT, and E. C.