Levinsenia gracilis (Tauber, 1879)

Lovell, Lawrence L. & Fitzhugh, Kirk, 2020, Taking a closer look: an SEM review of Levinsenia species (Polychaeta: Paraonidae) reported from California, Zootaxa 4751 (2), pp. 257-275 : 259-262

Levinsenia gracilis (Tauber, 1879)

Figures 1 A–D; 2A–D, 7A, B

Aonides gracilis Tauber, 1879: 115 .

Levinsenia gracilis .–Mesnil & Caullery, 1898: 136–138, Pl. 6, Fig. 10.— Blake 1996: 33–44, Fig. 2.1.

Paraonis (Paraonis) gracilis . Cerruti, 1909: 468, 498, 504.—Pettibone, 1963: 301–302, Fig. 79a–d.

Paraonis gracilis . —Eliason, 1920: 55–56, Fig. 16a-e. Wesenberg-Lund, 1950: 32, Pl. 7, Fig. 34.—Uschakov, 1955: 286, Fig. 103a–b. Hartman, 1957: 330–331, Pl. 22, Figs 4–5 (synonymy); 1969: 75–76, Figs 1–3 .

Paraonis gracilis gracilis . —Day, 1967: 566, Fig. 24.4a–b.

Paraonis gracilis minuta . Hartmann-Schröder, 1965: 197–198, Figs 181–182. Fide Strelzov, 1973.

Paraonis (Paraonides) gracilis .—Monro, 1930: 150–152, Fig. 58.

Paraonis filiformis —Hartman, 1953: 39–40, Fig. 12B–C. Fide Hartman, 1957.

Paraonis (Paraonis) ivanovi .—Banse & Hobson, 1968: 23, Fig. 5f . Fide Strelzov, 1973.

Tauberia gracilis .— Strelzov, 1973: 127–133, Figs 14, 54–57 (synonymy).

Material examined. Denmark, Samsø, Kattegat, coll. Winther, syntype ( NHMD 108749 (prev. ZMUC CRU- 966 )), as Aonides gracilis Tauber ; Kattegat, Frederikshavn, Hirsholmene, July 23, 1949, coll. P.L. Kramp , det. E. Wesenberg-Lund, 1 specimen ( LACM-AHF 12549 ) .— Sweden, Kattegat, Värö, Ringhals Sund, 19 m depth, Sta. L7, 57°16.1’N, 12° 4.8’E, 0.1 m ² Smith-McIntyre grab, 11 March 1975, coll. KMS Kristineberg, sample 2, det. M.E. Petersen, 1 specimen on SEM stub ( LACM-AHF 12548 ), 9 specimens in ethanol ( NHMD 644302 ) .— Iceland, Danish Ingolf Expedition, Sta. 138, 63°26’N, 7°56’W, 887 m depth, 10 August 1896 , det. E. Wesenberg-Lund, 2 specimens (1 in ethanol, 1 mounted on SEM stub) ( LACM-AHF 12550 ); NE of Iceland, 65°45’N, 12°10’W, 107 m depth, 13 June 1925, coll. Fisheries Board of Scotland , det. E. Wesenberg-Lund, 1 specimen ( NHMD 644303 ) .— Greenland, SW Greenland, Bankeundersøgelserne, Sta. 37 B, April 1975, 1 specimen ( NHMD 644314 ); SW Greenland, Bankeundersøgelserne, Sta. 31-B, April 1975, 1 specimen ( NHMD 644315 ); SW Greenland, Bankeundersøgelserne, Sta. 3C, April 1975, 5 specimens ( NHMD 644316 ); SW Greenland, Bankeundersøgelserne , Sta. 81A, April 1975, 1 specimen ( NHMD 644318 ) .— USA, California, Santa Barbara County, Santa Barbara Channel, 12.7 miles bearing 86.6° True from Pt. Conception Light, 34°27’25’’N, 120°12’55’’W, 17.4 m depth, Hayward orange peel grab, R / V Velero IV, Sta. 4938-57, coll. Allan Hancock Foundation, 09 April 1957, 25+ specimens (1 specimen on SEM stub, other specimens in ethanol ( LACM-AHF 12551 ); Northern Channel Islands, north of Santa Cruz Island, Bight 2008, Sta. 7556, 92 m depth, 34.08°N, 119.71°W, 0.1 m ² Van Veen , 1.0 mm sieve, 09 September 2008, 2 specimens ( LACM-AHF 12560 ).— San Diego County, Carlsbad , Encina , National Pollution Discharge Elimination System ( NPDES) 9232, Sta. G 1, replicate 4, 45 m depth, 33°06.42’N, 117°20.75’W, 0.1 m ² Van Veen grab, February 1992, 3 specimens (1 specimen on SEM stub, 2 in ethanol) ( LACM-AHF 12552 ); San Onofre , San Onofre Nuclear Generating Station ( SONGS) D6700-60 , Sta. XXXI, replicate 1, 33.32°N, 117.51°W, 18.3 m deep, 0.008 m ² diver core, 0.5 mm sieve, 16 September 1981, 1 specimen ( LACM-AHF 12553 )— Orange County, Huntington Beach, Orange County Sanitation District ( OCSD) Survey 8501, Sta. 13, rep. 3, 33°35.31’N, 118°2.94’W, 60 m depth, 0.1 m ² Van Veen grab, 18 August 1985, 1.0 mm sieve, 1 specimen ( LACM-AHF 12554 ); Huntington Beach , OCSD Survey 8501, Sta. 30, rep. 1, 33°35.49’N, 118°2.89’W, 30 m depth, 0.1 m ² Van Veen grab, 20 August 1985, 1.0 mm sieve, 1 specimen ( LACM-AHF 12555 ); Huntington Beach , OCSD Survey 9276, Sta. Control, rep. 5, 33°36.04’N, 118°5.39’W, 60 m depth, 0.1 m ² box core, 1 specimen ( LACM-AHF 12556 ); Huntington Beach , OCSD Survey 9382, Sta. LA3, rep. 1, 33°31.72’N, 117°54.73’’W, 436 m depth, 0.3mm sieve, 25 January 1993, 0.1m ² Van Veen grab, 4 specimens ( LACM-AHF 12557 ); Dana Point , SCWD NPDES Sta. A, rep. 3, ~ 33.45°N, 117.68°W, 39.6 m depth, 0.1m ² Van Veen grab, 1.0 mm sieve, 16 December 1981, 1 specimen ( LACM-AHF12558 ). — Los Angeles County, Southern California Coastal Water Research Project ( SCCWRP) Los Angeles County Stormwater, survey 1914, Sta. MBD25, rep. 1, Van Veen grab, 1 specimen ( LACM-AHF 12559 )— Monterey County, Monterey Canyon , MBARI sample V3147 – C17, 1004 m depth, 7 January 2008, 36.74°N, 122.28°W, ROV Ventana , 1 specimen ( LACM-AHF 12561 ); MBARI sample V3124 ─ C24, 1004 m depth, 7 January 2008, 36.74°N, 122.28°W, ROV Ventana , 1 specimen ( LACM-AHF 12562 ); MBARI sample V3147 ─ C27, 1004 m depth, 7 January 2008, 36.74°N, 122.28°W, ROV Ventana , 1 specimen ( LACM-AHF 12563 ).— Washington, Puget Sound, Seattle Metro, Publically Owned Treatment Works ( POTW), West Point , METRO / TPPS Sta. XIII-100, 47.66°N, 122.46°W, 30.5 m depth, 28 September 1981, 0.1 m ² Van Veen grab, 1.0 mm sieve, 7 specimens ( LACM-AHF 12564 ) .

Description. Specimens up to 30 mm long, 0.2–0.3 mm wide. Body thin, dorsally flattened in prebranchial region, thereafter round in cross section, uniformly wide. Body tan, gut visible in posterior chaetigers. Prostomium triangular, slightly longer than wide; terminal sensory organ present; eyes absent; nuchal organs ciliated slits; median antenna absent ( Fig. 1A ). Prebranchial region 5–7 segments, followed by 7–16 branchial pairs (size dependent) ( Figs 1B , 2A ); branchiae distally tapered, blunt tipped, ciliated laterally, with dorsal transverse ciliary bands between branchiae ( Figs 1C , 2B ). Notopodial post-chaetal lobes as low mounds in prebranchial chaetigers, digitate in branchial region, shorter in post-branchial region; neuropodial post-chaetal lobes absent. Notopodial sensory pores present along entire body ( Figs 1D , 2C ), may have projecting filament (mucous strand?). Notochaetae capillary throughout; neurochaetae capillary only for anterior segments, post-branchially an anterior capillary row and posterior row of slightly curved, tapering acicular chaetae with fringe of fibrils along distal convex side, usually 3–7 acicular chaetae per fascicle ( Figs 1D , 2D ). Pygidium with pair of anal cirri.

Methyl green stain. Ventral banding in branchial region, no MG spots in post-branchial region ( Fig. 7 A–B). Specimens from Sweden and California with similar staining patterns.

Remarks. Several species of Paraonidae are reported with broad geographic and depth ranges. SEM images of Levinsenia gracilis from near the type locality (Baltic Sea) and Southern California Bight were compared and found to be indistinguishable morphologically. Ciliary bands dorsally connecting the branchiae are newly described for the species and consistent in material from both locations. Methyl green staining has not been previously published with paraonid specimens, but the same pattern is present in all L. gracilis specimens stained. For information on diagnostic character differences, see the dichotomous key below and table of character distributions ( Table 2).

Levinsenia gracilis has a reported cosmopolitan distribution with a broad bathymetric range ( Strelzov 1973, Blake 1996). Material examined from Denmark, Sweden, Iceland, Greenland, Washington, USA, and California, USA, were all collected within the reported (very wide) depth range, are morphologically similar, and represent occurrences indicating a broad geographic distribution. The specimen from the Zoological Museum, Natural History Museum of Denmark, is noted as the only surviving syntype and is in four pieces, but the characters match the published description of L. gracilis .

It cannot be assumed that all literature reports of Levinsenia gracilis from other locations are correctly identified. Nine species of Levinsenia ( Table 1) have been described since Strelzov (1973) reviewed the family. Several of these new species were originally identified as L. gracilis , but later re-examined and determined to be new (see WoRMS).

Type locality. Denmark .

Distribution. Cosmopolitan, subtidal to 3000+ m.

Figures

FIGURE 1. Levinsenia gracilis (Tauber, 1879), adult, California specimen: (A) prostomium with palpode, nuchal organs, dorsal view; (B) anterior body with branchiae, lateral view; (C) transverse ciliary bands between branchiae, dorsal view; (D) notopodial glandular pores, acicular neurochaetae with fibrils, lateral view. Abbreviations: ci, cilia; no, nuchal organ; pl, post-chaetal lobe; so, palpode sensory organ; sp, sensory pores. Scale bars: A, 50 µm; B, 300 µm; C, 100 µm; D, 15 µm.

FIGURE 2. Levinsenia gracilis (Tauber, 1879), adult, Sweden specimen: (A) anterior body with branchiae, lateral view; (B) transverse ciliary bands between branchiae, dorsal view; (C) notopodial glandular pores, lateral view; (D) acicular neurochaetae with fibrils, lateral view. Abbreviations: ci, cilia; pl, post-chaetal lobe; sp, sensory pores. Scale bars: A, 500 µm; B, 100 µm; C, 10 µm; D, 10 µm.

FIGURE 3. Levinsenia kirbyorum Lovell, 2002, adult: (A) prostomium with palpode, nuchal organs, dorsal view; (B) transverse ciliary bands between branchiae, dorsal view; (C) notopodial glandular pores, lateral view; (D) posterior chaetal fascicle showing multiple rows of acicular spines, lateral view. Abbreviations: ci, cilia; no, nuchal organ; pl, post-chaetal lobe; so, palpode sensory organ; sp, sensory pores. Scale bars: A, 200 µm; B, 200 µm; C, 20 µm; D, 50 µm.

FIGURE 4. Levinsenia multibranchiata (Hartman, 1957), paratype AHF-LACM POLY 648, adult: (A) prostomium with palpode, nuchal organs, dorsal view; (B) branchial region, dorsal view; (C) notopodial glandular pores, lateral view; (D) acicular neurochaetae with fibrils, lateral view. Abbreviations: no, nuchal organ; pa, palpode; pl, post-chaetal lobe; sp, sensory pores. Scale bars: A, 100 µm; B, 300 µm; C, 20 µm; D, 30 µm.

FIGURE 5. Levinsenia oculata (Hartman, 1957), adult: (A) prostomium with palpode, nuchal organs, dorsal view; B) anterior body with branchiae, dorso-lateral view; (C) low transverse ciliary bands between branchiae, dorso-lateral view; (D) notopodial glandular pores, lateral view; (E) posterior chaetal fascicle showing capillary and acicular spines, lateral view. Abbreviations: no, nuchal organ; sp, sensory pores. Scale bars: A, 200 µm; B, 300 µm; C, 50 µm; D, 10 µm; E, 20 µm.

FIGURE 7. A–G, Levinsenia spp. methyl green staining patterns: A, L. gracilis California specimen; B, L. gracilis Sweden specimen; C, L. kirbyorum; D, L. multibranchiata; E, F, L. oculata; G, L. barwicki n. sp.; H, L. kirbyorum, posterior neuropodial fascicle.