Caecum californicum Dall in Orcutt, 1885

Raines, Bret K., 2020, A Rosetta Stone for eastern Pacific Caecidae (Gastropoda: Caenogastropoda), Zootaxa 4827 (1), pp. 1-146 : 99-103

Caecum californicum Dall in Orcutt, 1885

Figures 78 A–F, 79A–L, 80A–B, 127E

Caecum cooperi Carpenter, 1864: 216 , 2 syntypes USNM 15719 , San Diego, California, [non S. Smith, 1862].

Caecum californicum Dall in Orcutt, 1885: 541 , [nomen novum].

Caecum cooperi — Tryon, 1886: 219, pl. 66, fig. 65; Palmer, 1958: 173, pl. 20, figs. 8–9.

Caecum californicum —Abbott, 1974: 91, fig. 871; McLean, 1978: 29, fig. 14.1; Hertz, 1979a: 2; Draper, 1985: 3, fig. 2; Skoglund, 1992: 28; Raines, 2019: 100, figs. 2C–D, [non Cruz, 2007: 134, fig. 4].

Material examined. In addition to the type material the following lots were examined. NHMLAC: LACM 1972 - 98.26 , Pt. Mugu, Ventura Co., California , 3–6 m, 17 sh ; LACM 1962 - 21.32 , Flat Rock Pt., Palos Verdes Peninsula, Los Angeles Co., California , intertidal, 2 sh ; LACM 1970 - 63.9 , Bluff Cove, Palos Verdes Peninsula, Los Angeles Co., California , intertidal, 19 sh ; LACM 1965 - 79.23 , Lunada Bay , Palos Verdes Peninsula, Los Angeles Co., California, intertidal, 80 sh ; LACM 1972 - 96.29 , Royal Palms State Beach, Palos Verdes Peninsula, Los Angeles Co., California , 3–7 m, 55 sh ; LACM 1969 - 72.31 , White Pt, San Pedro, Los Angeles Co., California , intertidal, 75 sh ; LACM 1948 - 5.24 , Bodega Head, Sonoma Co., California , intertidal, 2 sh ; LACM 1965 - 60.12 , Malaga Cove, Palos Verdes Peninsula, Los Angeles Co., California , 3–7 m, 6 sh ; LACM 1974 - 80.16 , Crescent Bay , Laguna Beach, Orange Co., California, 10 m, 90 sh ; LACM 1971 - 100.31 , Mission Bay , San Diego Co., California, 2–7 m, 100 sh ; LACM 1972 - 109.41 , La Jolla, San Diego Co., California , 22–24 m, 30 sh ; LACM 1965 - 29.31 , Point Loma, San Diego Co., California , intertidal, 200 sh ; LACM 1972 - 111.22 , Point Loma, San Diego Co., California , 12 m, 140 sh ; LACM 1960 - 22.33 , Monterey Bay , Monterey Co., California, 20 m, 25 sh ; LACM 1967 - 85.18 , Santa Barbara, Santa Barbara Co., California , 18 m, 3 sh ; LACM 1968 - 35.15 , Santa Cruz Island , Santa Barbara Co., California, 12 m, 3 sh ; LACM 1941 - 338.7 , San Miguel Island , Santa Barbara Co., California, 27 m, 6 sh ; LACM 1938 - 230.5 , Santa Rosa Island , Santa Barbara Co., California, 28 m, 1 sh ; LACM 1971 - 243.15 , Malibu, Los Angeles Co., California , 10–12 m, 25 sh ; LACM 1971 - 242.17 , Malibu, Los Angeles Co., California , 12 m, 7 sh ; LACM 1973 - 11.42 , Santa Cruz Island , Santa Barbara Co., California, 11–12 m, 3 sh ; LACM 1941 - 61.8 , Santa Rosa Island , Santa Barbara Co., California, 7–9 m, 1 sh ; LACM 1967 - 61.40 , Geronimo Island , Baja California, Mexico, 7–8 m, 28 sh ; LACM 1971 - 91.55 , Sacramento Reef , Geronimo Island, Baja California, Mexico, 7–12 m, 55 sh ; LACM 1946 - 1.12 , Punta Rosarito, Baja California, Mexico, intertidal, 20 sh ; LACM 1946 - 2.11 , Millers Landing, Baja California, Mexico, intertidal, 3 sh ; LACM 171 - 151.56 , Cedros Island , Baja California, Mexico, 5–12 m, 120 sh ; LACM 1972 - 113.30 , Cedros Island , Baja California, Mexico, 10 m, 90 sh ; LACM 1972 - 114.35 , Cedros Island , Baja California, Mexico, 14 m, 100 sh ; LACM 1971 - 94.31 , Cedros Island , Baja California, Mexico, 18–31 m, 10 sh ; LACM 1971 - 92.38 , Cedros Village , Cedros Island, Baja California, Mexico, 6–15 m, 120 sh ; LACM 1972 - 115.33 , Piedra Colorado , Baja California, Mexico, 18–20 m, 100 sh ; LACM 1967 - 65.29 , Cedros Village , Cedros Island, Baja California, Mexico, 5–8 m, 100 sh ; LACM 1967 - 64.23 , Cedros Village , Cedros Island, Baja California, Mexico, 18 m, 13 sh ; LACM 1933 - 145.1 , S Bay Landing, Cedros Island , Baja California, Mexico, 7–10 m, 7 sh ; LACM 1933 - 145.10 , 5 fm Bank , 4 miles SW of Cedros Island, Baja California, Mexico, 12–16 m, 80 sh ; LACM 1971 - 3.35 , Abreojos Point , Baja California, Mexico, 7–10 m, 100 sh ; LACM 1941 - 352.5 , NW of Natividad Island , Baja California Sur, Mexico, 55 m, 11 sh ; LACM 1972 - 117.37 , NW of Natividad Island , Baja California Sur, Mexico, 18–24 m, 30 sh ; LACM 1972 - 116.26 , NW of Natividad Island , Baja California Sur, Mexico, 12 m, 15 sh ; LACM 1940 - 2.19 , Turtle Bay , Baja California Sur, Mexico, 50–55 m, 35 sh ; LACM 1971 - 170.46 , Thurloe Head , Baja California Sur, Mexico, 14–18 m, 90 sh ; LACM 1966 - 8.27 , Santa Margarita Island , Baja California Sur, Mexico, intertidal to 2 m, 180 sh ; LACM 1971 - 17.23 , Arroyo Conejo , Baja California Sur, Mexico, 25 m, 1 sh ; LACM 1967 - 69.15 , Hughes Point , Santa Maria Bay, Baja California Sur, Mexico, 2–5 m, 37 sh ; LACM 1940 - 245.2 , Santa Maria Bay , Baja California Sur, Mexico, 90 m, 2 sh ; LACM 1971 - 178.53 , San Pablo Point , Baja California Sur, Mexico, 20–30 m, 110 sh ; LACM 1971 - 177.34 , San Pablo Point , Baja California Sur, Mexico, 21–24 m, 80 sh ; LACM 1971 - 14.62 , Entrada Point , Baja California Sur, Mexico, 3–15 m, 125 sh ; LACM 1971 - 5.28 , Pequena Point , Baja California Sur, Mexico, 3–5 m, 75 sh ; LACM 1967 - 71.12 , Magdalena Island , Magdalena Bay, Baja California Sur, Mexico, 8–10 m, 45 sh ; LACM 1971 - 183.51 , Man-O-War Cove , Magdalena Bay, Baja California Sur, Mexico, intertidal to 11 m, 150 sh ; LACM 1971 - 180.23 , San Juanico Bay , Baja California Sur, Mexico, 10 m, 8 sh ; LACM 1967 - 66.54 , Asuncion Island , Baja California Sur, Mexico, 8–21 m, 300+ sh ; LACM 1966 - 13.32 , Cape San Lucas, Baja California Sur, Mexico, intertidal, 31 sh ; LACM 1967 - 76.11 , Cape San Lucas , Baja California Sur, Mexico, 27–35 m, 6 sh ; LACM 1967 - 75.15 , Cape San Lucas , Baja California Sur, Mexico, 9–24 m, 2 sh ; LACM 1967 - 45.57 , Todos Santos Island , Baja California, Mexico, 10–21 m, 11 sh ; LACM 1964 - 32.38 , N of Ensenada , Baja California, Mexico, intertidal, 360 sh ; LACM 1966 - 5.25 , N of Ensenada , Baja California, Mexico, intertidal, 55 sh ; LACM 1963 - 53.31 , N of Ensenada , Baja California, Mexico, intertidal, 120 sh ; LACM 1966 - 4.25 , Todos Santos Bay , Baja California, Mexico, 10–21 m, 11 sh ; LACM 1963 - 42.38 , Banda Point , Baja California, Mexico, 3–10 m, 9 sh ; LACM 1963 - 54.33 , Banda Point , Baja California, Mexico, intertidal to 7 m, 75 sh ; LACM 1967 - 40.41 , San Martin Island , Baja California, Mexico, 18 m, 3 sh ; LACM 1967 - 2.56 , San Tomas Point , Baja California, Mexico, intertidal, 2 sh ; LACM 1966 - 1.45 , S of San Tomas Point , Baja California, Mexico, intertidal to 7 m, 25 sh . SBMNH: SBMNH 214997 , Point Loma, San Diego County, California, USA, 20 sh ; SBMNH 620546 , Caleta Lalo , Sonora, Mexico, 15 m, 1 sh ; SBMNH 142237 , Fraser Point, Santa Barbara County, California, USA, intertidal, 21 sh ; SBMNH 142248 , West End , Gill Station 73, Santa Barbara County, California, USA, intertidal, 5 sh ; SBMNH 620318 , Cabo San Lucas, Playa Barco Virago, Baja California Sur, Mexico, 25 sh ; SBMNH 141300 , Forney’s Point, Santa Barbara County, California, USA, intertidal, 60 sh ; SBMNH 142097 , Hammonds Point, Santa Barbara County, California, USA, intertidal, 7 sh ; SBMNH 142433 , Hammonds Point, Santa Barbara County, California, USA, intertidal, 1 sh ; SBMNH 33319 , San Pedro, Los Angeles County, California, USA, 6 sh ; SBMNH 142311 , Montana de Oro, San Luis Obispo County, California, USA, intertidal, 1 sh ; SBMNH 620818 , Cabo San Lucas , Baja California Sur, Mexico, 20–50 m, 200 sh ; SBMNH 349187 , Forney’s Cove, Santa Barbara County, California, USA, 8 m, 7 sh ; SBMNH 349195 , Lions Rock, San Luis Obispo County, California, USA, 28 m, 10 sh ; SBMNH 215006 , Point Fermin, Los Angeles County, California, USA, 5 sh ; SBMNH 215000 , La Jolla, Bird Rock, San Diego County, California, USA, intertidal, 1 sh ; SBMNH 214934 , La Jolla, Bird Rock, San Diego County, California, USA, intertidal, 1 sh ; SBMNH 2167 , Malaga Cove, Los Angeles County, California, USA, 8 sh ; SBMNH 10035 , San Diego, San Diego County, California, USA, 7 sh ; SBMNH 15735 , Bahia de los Angeles, Baja California [Norte], Mexico, 45 sh ; SBMNH 127009 , Laguna Guerrero Negro, Baja California [Norte], Mexico, 6 sh ; SBMNH 124932 , Punta San Carlos , 4 mi SW of, Baja California [Norte], Mexico, 25 m, 15 sh ; SBMNH 124392 , Isla Ballena, Baja California Sur, Mexico, 1 sh ; SBMNH 118838 , Santa Barbara Island , Santa Barbara County, California, USA, 16 sh ; SBMNH 114640 , Punta Banda, Baja California [Norte], Mexico, intertidal, 5 sh ; SBMNH 113693 , Laguna Ojo de Liebre , Baja California Sur, Mexico, 2 sh ; SBMNH 124336 , Laguna Ojo de Liebre , Baja California Sur, Mexico, 75 sh ; SBMNH 619733 , Reef Point, Orange County, California, USA, 500 sh ; SBMNH 103777 , Reef Point, Orange County, California, USA, 100 sh ; SBMNH 103660 , La Jolla, San Diego County, California, USA, 1 sh ; SBMNH 100235 , Del Monte, Monterey County, California, USA, 22 m, 20 sh ; SBMNH 6901 , Malaga Cove, Los Angeles County, California, USA, 11 sh ; SBMNH 7399 , Redondo Beach, Los Angeles County, California, USA, 1 sh ; SBMNH 2415 , Palos Verdes, Rocky Point, Los Angeles County, California, USA, 4 m, 10 sh ; SBMNH 214933 , Bahia Magdalena , Baja California Sur, Mexico, intertidal, 1 sh ; SBMNH 215002 , San Diego, San Diego County, California, USA, 50 sh ; SBMNH 215022 , Bahia Magdalena , Baja California Sur, Mexico, intertidal, 1 sh ; SBMNH 214946 , San Diego, San Diego County, California, USA, 17 sh ; SBMNH 6900 , Palos Verdes, Rocky Point, Los Angeles County, California, USA, 51 sh ; SBMNH 18672 , Palos Verdes, Rocky Point, Los Angeles County, California, USA, 31 sh ; SBMNH 100908 , San Pedro Bay, Los Angeles County, California, USA, 3 sh ; SBMNH 149029 , La Jolla, San Diego County, California, USA, 900 sh ; SBMNH 15736 , Puertecitos, Baja California [Norte], Mexico, 6 sh ; SBMNH 127137 , Chacala , Nayarit, Mexico, 3–5 m, 1 sh ; SBMNH 126319 , Puertecitos, 1.5 mi N [Playa Curbina], Baja California [Norte], Mexico, intertidal, 30 sh ; SBMNH 620299 , Flanders Bay , Suffolk County, New York, USA, 20 sh ; SBMNH 619732 , Bahia Magdalena , Baja California Sur, Mexico, intertidal, 4 sh ; SBMNH 129732 , Agua de Chale , Baja California [Norte], Mexico, intertidal, 3 sh ; SBMNH 620181 , Punta Final, Baja California [Norte], Mexico, 11 sh ; SBMNH 620183 , Bahia de los Angeles, Baja California [Norte], Mexico, intertidal, 1 sh ; SBMNH 620186 , San Diego, San Diego County, California, USA, 25 sh ; SBMNH 620323 , Punta Entrada , Baja California Sur, Mexico, 10–13 m, 100 sh ; SBMNH 620325 , San Diego, San Diego County, California, USA, 25 sh ; SBMNH 123193 , Bahia Sebastian Vizcaino , Baja California [Norte], Mexico, 34 m, 25 sh ; SBMNH 114034 , Isla Natividad, opposite Flat Rock, Baja California Sur, Mexico, intertidal, 1 sh ; SBMNH 124371 , Chester Rocks , 12.5 mi E of, Bahia Sebastian Vizcaino, Baja California [Norte], Mexico, 32 m, 7 sh ; SBMNH 116242 , Bahia Tortugas, Baja California Sur, Mexico, 5 m, 100 sh ; SBMNH 131647 , Bahia San Juanico , Baja California Sur, Mexico, 36 m, 20 sh ; SBMNH 131984 , Point Loma, San Diego County, California, USA, 33 m, 1 sh ; SBMNH 110486 , Bathhouse Cliff, Santa Barbara County, California, USA, 30 sh ; SBMNH 123197 , Bahia Sebastian Vizcaino , Baja California [Norte], Mexico, 34 m, 1 sh ; SBMNH 118231 , Punta Hughes, Baja California Sur, Mexico, 8 sh ; SBMNH 114036 , Isla Natividad, opposite Flat Rock, Baja California Sur, Mexico, intertidal, 25 sh ; SBMNH 116333 , Isla Asuncion , Baja California Sur, Mexico, 12 m, 30 sh ; SBMNH 621314 , Bahia Magdalena , Baja California Sur, Mexico, 200 sh ; SBMNH 621315 , Puerto San Carlos , Bahia Magdalena, Baja California Sur, Mexico, 2–10 m, 500 sh ; SBMNH 622327 , Isla Santa Margarita , Baja California Sur, Mexico, 2–3 m, 5 sh ; SBMNH 622383 , Isla Ballena , Baja California Sur, Mexico, 12–17 m, 25 sh ; SBMNH 622523 , San Pedro Los Angeles County, California, USA, 5 sh .

Original diagnosis. “ C. (Anellum) t. parva, satis tereti, alba; annulis crebris acutioribus, angustis, circ. xxxiv – xxxviii, interstitiis subconcavis; septo subungulato; apice obtuso, haud elevato, margine laterali recto; apertura declivi, parum contracto et postice expanso; operculo?” Carpenter (1864: 216).

Description. Protoconch multispiral (about 1.75 whorls), planispiral, smooth ( Fig. 79A ), transition to teleoconch I marked by apertural varix ( Fig. 79A ). Teleoconch I short, smooth with weak axial growth lines ( Fig. 79B ), transition to teleoconch II marked by axial incised line ( Figs. 79A, D ). Teleoconch II about 2.5 times length of teleoconch I, sculptured with axial growth marks, transition to teleoconch III marked by change in sculpture ( Fig. 79D ). Teleoconch III sculptured with low, developing axial ribs ( Fig. 79E ), transition to teleoconch IV marked by change in sculpture ( Figs. 79 F–G). Teleoconch IV sculptured with flattened axial ribs and fine, dense, longitudinal striae in interspaces ( Fig. 79F ), transition to teleoconch V marked by suture, followed by change in sculpture ( Fig. 79H ). Teleoconch V sculptured with numerous, round to flattened ribs ( Figs. 79I, K ), transition to teleoconch VI marked by suture followed by increase in diameter ( Fig. 79K ). Teleoconch VI (last growth stage) average size for genus [Tol 2.50–2.80 mm], tubular, thick, stout, moderately and regularly arched [Larc: 0.80–0.90 mm; Arc: 0.26–0.30 mm], subcylindrical with slight increase in diameter from posterior to aperture, cream to light brown ( Figs. 78 A–B). Axial sculpture of 30–40 closely arranged, round to flattened ribs ( Figs. 79J, L ). Axial interspaces rather deep, vary in width ( Figs. 79J, L ). Surface smooth to glossy, with dense striae in interspaces ( Figs. 79J, L ). Striae easily worn away. Posterior [Dpe: 0.45–0.48 mm] with thick edge, squared shoulder ( Fig. 78C ). Septum mucronate, slightly protruding ( Fig. 78C ). Mucro with rounded point, positioned on dorsal margin ( Fig. 78C ). Aperture [Da: 0.48–0.62 mm] thick, slightly constricted ( Fig. 78C ). No varix. Lip smooth, with deflected peristome ( Fig. 78C ). Periostracum thin, smooth, light brown ( Fig. 78A ). Operculum thin, light brown; exterior surface with 6–7 concentric rings ( Figs. 78 D–E). Conceptual reconstruction of growth stages shown in Fig. 80A .

Distribution and Habitat. Sonoma County, California to Cape San Lucas, Baja California Sur, Mexico. Intertidal to 35 m. Abundant on sand and gravel substrates.

Remarks. Carpenter (1864) named the species Caecum cooperi ( Fig. 78F ), not realizing that the name had been previously used for a western Atlantic caecid. Twenty years later, noting the error and abundance of the species, Dall (1885) renamed it C. californicum .

Cruz (2007) reported Caecum californicum to be found in Ecuador. However, given that the closest confirmed population of C. californicum is nearly 4,800 km away and ocean currents do not support this distribution, the report is considered erroneous. Cruz’s figure is not detailed enough to identify the actual species.

Figures

FIGURE 78. Caecum californicum. A. Profile view with periostracum (LACM 1971-100.31). B. Profile view without periostracum (LACM 1971-100.31). C. Ventral view (SBMNH 33319). D. Operculum, exterior surface (LACM 1971-100.31). E. Operculum, interior surface (LACM 1971-100.31). F. Caecum cooperi holotype, USNM 15719.

FIGURE 79. Caecum californicum shells at different growth stages. A. Protoconch and teleoconchs I to II (LACM 1972- 109.41). B. Surface of teleoconch I (LACM 1972-109.41). C. Surface of teleoconch II (LACM 1972-109.41). D. Teleoconchs I to IV (LACM 1972-109.41). E. Surface of teleoconch III (LACM 1972-109.41). F. Surface of teleoconch IV (SBMNH 33319). G. Teleoconchs III to V (SBMNH 33319). H. Teleoconchs IV to V (LACM 1972-109.41). I. Surface of teleoconch V (LACM 1971-100.31). J. Surface of teleoconch VI (LACM 1971-100.31) K. Teleoconch V (LACM 1971-100.31). L. Teleoconch VI (LACM 1971-100.31).

FIGURE 80. Caecum californicum. A. Conceptual reconstruction of growth stages. B. Species distribution map.