Pseudochitinopoma occidentalis ( Bush, 1905 )

Kupriyanova, Elena K., Ten, Harry A. & Nishi, Ejiroh, 2012, A taxonomic revision of Pseudochitinopoma Zibrowius, 1969 (Annelida, Serpulidae) with description of two new species, Zootaxa 3507, pp. 57-78 : 68-72

Pseudochitinopoma occidentalis ( Bush, 1905)

( Figs 7 A–E, 8A–E)

Hyalopomatopsis occidentalis Bush, 1905: 229 –230, pl. 40: fig. 3, 22, pl. 44: figs 2, 4, 8, 9; Moore 1908: 362; 1923: 254; Hartman 1942: 89 –90.

Chitinopoma greenlandica [sic] – Pixell 1912: 790 –792, pl. 88: fig. 6a-c; Nelson-Smith 1967: 37, fig. 29 (in part).

Chitinopoma groenlandica – Berkeley 1930: 74; Berkeley & Berkeley 1942: 207; 1952: 129–130, 1961: 663; Haderlie 1971: 253, 256, Table 1 ; 1974: 11, figs 4, 7, 36 (fouling); Hartman 1969: 749 –750, 4 figs; Gavin & Macdonald 1977: Appendix A, p.2 (checklist); Haderlie & Donat 1978: 58.

Not Chitinopoma groenlandica ( Mörch, 1863) confused, fide Zibrowius 1969: 6.

Chitinopoma occidentalis – Hartman 1948: 49 –51, fig. 12; 1961: 44; Haderlie 1969: 186–189 (fouling); Smith & Haderlie 1969: 448 –449 (life history).

Pseudochitinopoma occidentalis – Zibrowius 1969: 7 –9 (redescription, synonymy); Long 1972: 54 –56; Bornhold & Milliman 1973: 371; Kozloff 1974: 115 (name in key); Hobson & Banse 1981: 108, 111, figs 27l, m; ten Hove & Jansen-Jacobs 1984: 166 (see below); Kozloff & Price 1987: 164 (name in key); Duggins & Eckman 1997; Duggins et al. 1990 (name only, ecology); Eckman & Duggins 1991, 1993, 1998 (name only, ecology); Hess 1993 (name only, reproduction); Anonymous 2001: 81 (name in checklist); Kupriyanova et al. 2006: 423, 427, 439 (phylogenetic position); Lehrke et al. 2007: 198, 199 (phylogenetic position), 203; Bastida-Zavala 2008: 38 –39; ten Hove & Kupriyanova 2009: 85.

Material studied. In the list below, all material in the collections of the USNM, unless otherwise mentioned, is from the USA, Alaska, Alaska King Crab Inventory, USFC and was (re-)identified by H.A. ten Hove 1981; likewise, material in the collections of the LACM-AHF was identified by H.A. ten Hove 1972, and all from the USA, California, unless stated otherwise.

Scale: A, B—0.5 mm, C— 1 mm, D—0.5 mm, E— 1 mm.

USA, Alaska, Cold Bay, approximately 55°12'N, 162°32'W (Google Earth), 27–59 m, Alaska King Crab Inventory #70–40, USFC, 17 October 1940, from tubes of Crucigera zygophora , det. O. Hartman 1948 ( USNM 21295, 7 specs, 14 tubes); Canoe Bay, approx. 55°34'N, 161°17'W (Google Earth), 110 m, Stn 160–41, 8 June 1941, removed from USNM 21297, tubes of Crucigera zygophora , det. O. Hartman 1948 ( USNM 81973, 1 spec., 3 tubes); Canoe Bay, 27–73 m, Stn 20–40 to 22–40, 21 September 1940 ( USNM 21296, several specs); off SW shore of Big Koniuji Island, approx. 54°N, 159°W, 46–55 m, Stn 82–40, 22 October 1940, ( USNM 21294, 40 specs, many juvenile, recently settled); Nagai Island, Mist Harbor, approx. 55°06'N, 159°48'W, 55 m, 27 October 1940, removed from USNM 21302, tubes of Crucigera zygophora , det. O. Hartman 1948 ( USNM 21302, ZMA V.Pol. 3483, 7 respectively 3 specs); Chignik Bay, Tuliumnit Point, approx. 56°15'N, 158°03'W, 55–75 m, R/V “ Albatross ” Stn 4283, 10 August 1903, det. M.H. Pettibone Chitinopoma groenlandica ( USNM 5584, 1 spec.); Kodiak, 57°42'N, 152°26'W, from fouling panels U.S. Naval Oceanographic Office, don. J.R. de Palma, det. H.A. ten Hove 1985 ( ZMA V.Pol. 3548, 3 specs); Kupreanof Strait, South side, 2 mi NW of Bare Island, approx. 57°58'N, 153°06'W, 24–27 m, L18–41, 2 April 1941, tubes of Crucigera zygophora , det. O. Hartman 1948 ( USNM 21300, ZMA V.Pol. 3482, 1 specimen with chain of eggs on posterior abdomen, 8 respectively 2 specs).

Canada, British Columbia, Strait of Georgia, Lasqueti Island, approximately 49°N, 124°W, 55 m, dredged, legit Th. Mortensen, 21 July 1915, from tube of Crucigera irregularis , det. H.A. ten Hove 1988 ( ZMUC -POL- 2154, 1 spec.); Barkley Sound, Grapper Inlet, Bamfield Marine Station, approx. 48°49'N, 125°07'W, legit T.A. Macdonald, 18 February 2004, det. E. Kupriyanova ( SAM E3501, 2 specs, one prepared for SEM).

USA, Washington State, San Juan Island, Friday Harbor Labs, approximately 48°N, 123°W, dredging, legit N. Budaeva, det. E. Kupriyanova (AM W38664, 1 spec.); same (AM W38665, 1 spec.); Indian Island, approx. 48°N, 122°W, from fouling panels, U.S. Naval Oceanographic Office, don. J.R. de Palma, det. H. A. ten Hove 1983–1985 ( ZMA V.Pol. 3547, 4 specs, tubes); California, Mendocino county, Fort Bragg, 39°26'31''N, 123°48'31''W, deep shaded channel with Crucigera and Serpula , intertidal, legit O. Hartman 29 June 1934, #N1898 [in her private catalogue Hartman crossed out Metavermilia and wrote in Vermiliopsis . She also noted that the animal in life was coloured bright vermilion; coordinates from Google Earth (Leslie H. Harris)] (LACM-AHF Poly 2915, 1 spec.); San Mateo County, Moss Beach, 37°31'29''N, 122°31' 0 3''W, intertidal, legit O. Hartman, July 1933, #N1899, det. Vermiliopsis [in her private catalogue Hartman noted “operculum vesicular, with a horny conical tip. Large thoracic collar. About 12 feathery tentacles. About 15 mm long. 6 prs. uncinig. tori. Tube white.” Hartman collected in many localities off Moss Beach; coordinates from Google Earth (LHH)] (LACM-AHF Poly 2916, 1 spec.); Monterey County, Monterey Bay, approx. 36°38'N, 121°52'W, on shale, 7.5 m, legit T. & E. Burch with A.G. Smith, Stn 3711, 20 August 1937, det. “ Eupomatus spec.”, n8831, redet. H.A. ten Hove 1989 (LACM-AHF Poly 2911, 8 specs); Carmel canyon(?, approx. 36°N, 121°W), legit J.H. McLean, April 1961, removed from USNM 41128 Vermiliopsis infundibulum det. E. & C. Berkeley [HAtH: thus presumably from Carmel Canyon] ( USNM 81974, 1 spec.); south side of Santa Cruz Island, 33°58'10''N, 119°37'40''W to 33°57'50''N, 119°38'10''W, grey sand, 73– 71 m, biological dredge, R/V “ Velero III” Stn 1191-40 D-1, 30 October 1930 (as Vermiliopsis , LACM- AHF Poly 2914, 3+ specs, 30 tubes); Los Angeles County, El Segundo, 6.25 mi off Hyperion Treatment Plant Exhaust Stack bearing 236° from true north, 33°52'30''N, 118°32'20''W -> 33°52' 0 0''N, 118°31'35''W, rocks & coarse sand, gravel, 62 m, biological dredge, R/V “ Velero IV “ Stn 5714–58, 18 April 1958, on tube of Vermiliopsis infundibulum , det. O. Hartman [HAtH: presently we would identify this as Vermiliopsis multiannulata (Moore, 1923) ] (LACM-AHF Poly 2924, 1 spec. in tube; complete set of compound microscope photographs of chaetae and uncini made by HAtH); L.A. Cty, 4.5 mi ESE of Point Fermin bearing 118° from true north, 33°40' 0 6''N, 118°12'45''W -> 33°39'58''N, 118°12'48''W, rock, tunicate, burrowing clams, 19–20 m, biological dredge, R/V “ Velero IV ” Stn 2032–51, 19 May 1951 (as? Vermiliopsis , LACM-AHF Poly 2925, 1 spec.); L.A. Cty, San Pedro, 5.5 miles from breakwater with Los Angeles Harbor lighthouse bearing 174° from true north, 33°37' 0 3''N, 118°14'21''W, fine mud & shaley rubble, on Laqueus californianus , 53 m, orange-peel grab, R/V “ Velero IV ” Stn 2125–52, 25 June 1952 (as Vermiliopsis , LACM-AHF Poly 2920, 1 spec., 2 tubes); L.A. Cty, Santa Catalina Island, off Long Point, 33°24'35''N, 118°21'15''W, rock, brachiopods, sponges, 73 m, R/V “ Velero II I ” Stn 900–38, 18 November 1938 (as Vermiliopsis , LACM-AHF Poly 2918, 4 specs; same, leeward side, 0.3 miles off Long Point, bearing 90° from true north, 33°24'30''N, 118°21'33''W -> 33°24'15''N, 118°21'35''W, sand, Laqueus californianus , alcyonaria and solitary corals, 77–123 m, biological dredge, R/V “ Velero IV ” Stn 2128–52, 25 June 1952, separated from Hyalopomatus [as Vermiliopsis ] biformis, [ AHF 002735] (LACM-AHF Poly 2912, 5 specs); same, 0.5 miles east of Long Point bearing 86° from true north, 33°24'24''N, 118°21'39''W, broken shell and Laqueus californianus bottom, 82 m, grab, R/V “Velero IV” Stn 2153–52, 27 September 1952, separated from Hyalopomatus [as Vermiliopsis ] biformis (LACM-AHF Poly 2913, 1 spec., sperms in tube); same, ½ mi W off Long Point bearing 360° from true north, ¼ mi off shore, 33°24' 0 0''N, 118°21'15''W, sand, brachiopods, 38–73 m, trawl, R/V “ Velero IV “ Stn 1426–41, 29 September 1941 (as? Vermiliopsis , LACM-AHF Poly 2919, 1 spec.); same, either 2 miles from Long Point Light bearing 154° from true north, 33°22'34''N, 118°20'52''W, dead Laqueus californianus , large sea stars, solitary corals, 59 m, orange-peel grab, R/V “ Ve l ero I V ” Stn 2121–52, 19 June 1952, or 2.2 miles from Long Point Light bearing 126° from true north, 33°22'29''N, 118°19' 0 8''W to 33°23'44''N, 118°20'23''W, Laqueus californianus and mud, 91–157 m, beam trawl, R/V “ Velero IV ” Stn 2288–53, 19 April 1953 (as Vermiliopsis , LACM-AHF Poly 2921= AHF 0 0 2781 or 0 0 2785, 2 labels in vial, likely samples were combined: 8+ specs, 40 tubes); San Diego County, La Jolla, off Scripps Institution of Oceanography, 32°51'58''N, 117°15'15''W, legit O. Hartman 4 March 1938, #N1900, [Hartman did a lot of collecting in the vicinity of SIO during her visits there. If she did not specify the actual site the above coordinates (taken from Google Earth) were used in the LACM catalogue; they are for the base of the current SIO pier which is at the same site as the old pier was in 1938 (LHH)] (as Vermiliopsis , LACM-AHF Poly 2917, 19 specs).

Mexico, Baja California Norte, Todos Santos Bay, 31°50'54''N, 116°38'05''W, 46– 27 m, legit R.P. Dales #142, 6 February 1951, O. Hartman #N5852 det.? Vermiliopsis [coordinates (taken from Google Earth) are for the bay off Ensenada, which in 1951 would have been the only city along the bay and where Dales probably stayed if he didn’t camp (LHH)] (LACM-AHF Poly 2922, ZMA V. Pol. 3170, 30+ specs, 100 tubes); same, legit R.P. Dales #141, O. Hartman #N5851 det.? Vermiliopsis (LACM-AHF Poly 2923, 10 empty tubes).

Description. TUBE: white, opaque, up to 50 mm long, 2.5 mm wide, with lumen of about 0.7 mm (max. 0.8 mm). Tubes more or less triangular in cross-section, longitudinal (median) keel sharp, but non-denticulate; sometimes forming sharp tooth above the aperture ( Fig. 7 E). Orifice, when attached, often with scooped lateral parts ( Fig. 7 D), occasionally former peristomes present as transverse ridges. Free, erect parts if present subtriangular, almost circular in cross-section with three very faint longitudinal keels. Outer hyaline granular layer absent.

BRANCHIAE: each lobe with 5–7 radioles arranged in semicircles to pectinately, not connected by interradiolar membrane. Pinnules spaced out, at least 1.5 their own width apart, radioles ending with long terminal filaments tips, 1.5–3 times longer than normal pinnules ( Fig. 7 E). Mouth structures, prostomial and branchial eyes not observed.

OPERCULUM: with semi-transparent to yellowish or brownish slightly convex endplate to conical cap, proximally mostly gradually merging into ampulla ( Fig. 7 B–C, E). Endplate rarely with distal thickened edge, almost a circular ridge. Ampulla and cap together 0.6 mm long, 0.35 mm wide.

PEDUNCLE: smooth, circular in cross-section, only slightly thicker than radioles; inserted almost near median line. At most a faint constriction present below ampulla.

COLLAR AND THORACIC MEMBRANES: collar with a large ventral lobe, well separated from two laterodorsal ones; very high, covering up to half of branchiae, with entire edge ( Fig. 7 C). Thoracic membranes wide, ending at chaetiger 2, but projecting as rounded lobes to chaetiger 3.

THORAX: with collar chaetiger, and six uncinigerous chaetigers. Collar chaetae of two types: special fin-andblade ( Fig. 8 A) with proximal denticulate fin not separated from distal limbate blade (however, under a compound microscope seemingly with small gap between fin and blade) and narrowly limbate, almost capillary. Subsequent chaetae limbate, of two sizes ( Fig. 8 B). Apomatus chaetae absent. Thoracic tori of similar size along thorax, positioned close to each other, located almost on lateral line of mid-thorax, triangular depression absent. Uncini along entire thorax saw-shaped, with 10–12 teeth, anterior peg of uncini flat blunt, slightly gouged underneath (dental formula P:1:1:1:1:1:1:1:1:1:1:1, Fig. 8 C).

ABDOMEN: up to 60 abdominal chaetigers. Chaetae true-trumpet-shaped, with narrow and long denticulate tip of about 30 teeth arranged in two rows ( Fig. 8 E). Capillary chaetae absent posteriorly. Abdominal uncini raspshaped, with 3–4 rows of teeth and 9–10 teeth in profile view anteriorly (dental formula P:4:3:3:3:3:3:3:3:3:?3), up to six rows of teeth and about 12 in profile view posteriorly; anterior peg of uncini flat, slightly gouged ( Fig. 8 D). Pygidium bilobed.

SIZE: length up to 20 mm, width of thorax 0.7 mm. Branchiae and operculum, accounting for 1/7th of entire length.

COLOUR: Body whiteish, radioles and peduncle with reddish bands ( Fig. 7 B).

Distribution. Pacific coast of North America: from southern coast of Alaskan Peninsula to Baja California, Mexico.

Reproduction. Unfertilized eggs are stored within the tube in a depression of the abdomen ( Kupriyanova et al. 2001), also see Fig. 7 A. Fertilization is apparently external, at least, no spermatophores have been reported, but the sperm morphology is unknown either. Egg diameter is approximately 60 μm, after artificial fertilization in the lab zygotes easily develop into planktotrophic trochophores ( Hess 1993; Kupriyanova, unpubl.). Kupriyanova et al. (2001) mentioned large spoon-shaped leaflets near orifice were found on tubes of Pseudochitinopoma occidentalis based on unpublished data of ten Hove. They stated that whether these leaflets are also used for brooding is unclear. Tubes with such leaflets were re-examined (see Fig. 7 D) and we conclude that they are too shallow to be used for incubation.

Remarks. Zibrowius (1969) does not mention distinctly large and high collar of P. occidentalis , though he unraveled the confused history and use of the name Chitinopoma groenlandica , (alternative spelling greenlandica ), which partly is indeterminable, but otherwise a mix-up of P. occidentalis and C. serrula ( Stimpson, 1854) . Attention is drawn here to an as yet to our knowledge unexploited character, the spacing of the pinnules on the radioles. In many taxa, the bases of pinnules are almost touching, but here they are spaced out.

Figures

FIGURE 7. Pseudochitinopoma occidentalis, AM W 38664, A—a string of unfertilized eggs from opened tube, B—intact live animal in the tube, (photos N. Budaeva); AM W 38665, C—dorsolateral view of animal removed from the tube, stained with methyl blue; D—SEM of scoops (or leaflets) outside the tube entrance (indicated by arrows); AM W 38664, E—view of animal in the tube.

FIGURE 8. Pseudochitinopoma occidentalis. SAM E 3501, SEM, A—fin-and-blade collar chaetae, B—thoracic chaetae, C—thoracic uncini, D—abdominal uncini, E—abdominal chaeta with a hollow tip. Scale: A— 10 µm, B—E— 5 µm.