Spiophanes norrisi, Blank, Miriam, 2009

Blank, Miriam, 2009, Spiophanes norrisi sp. nov. (Polychaeta: Spionidae) — a new species from the NE Pacific coast, separated from the Spiophanes bombyx complex based on both morphological and genetic studies, Zootaxa 2278, pp. 1-25 : 11-15

Spiophanes norrisi sp. nov.

( Figs 5 –6)

Spiophanes bombyx . – Light, 1978: 60 –62, figs 60–61. – Blake, 1996: 146 –147, figs 4.18.a–e. –Meißner, 2005: 54–58 (in part).

S. chilensis : –Hartmann– Schröder, 1965: 214 –218, figs 208–211 (in part, not holotype = S. duplex , compare Meißner 2005, p. 31).

Type material. HOLOTYPE: NE Pacific Ocean: Mexico: Magdalena Bay: Entrada Point, anchorage, 24°32.7' N, 112°04.083' W, surfgrass & tidepools, R/V Velero IV, station 1962-50, cruise 42, 3-V-1950, collected Allan Hancock Foundation, 1 complete specimen (LACM-AHF V. 1962 -50).

PARATYPES: NE Pacific Ocean: Mexico: Magdalena Bay: Entrada Point, anchorage, 24°32.7' N, 112°04.083' W, surfgrass & tidepools, R/V Velero IV, station 1962-50, cruise 42, 3-V-1950, collected Allan Hancock Foundation, 19 specimens (LACM-AHF V. 1962 -50).

Non– type material. NE Pacific Ocean: Alaska: Chukchi Sea: 67°44.483' N 164°33.750' W, 5.7 m, sand/gravel/peat, 17- VIII-1976, 2 specimens ( CAS 22168), Bering Sea: St. Matthew Basin: 61°14.800' N 167° 08.900 W, 22.4 m, 25- V- 1980, 11 specimens ( CAS 027086), 58°47.000' N 164°15.000' W, 35 m, 23- V-1976, 4 specimens ( CAS 023968), 58°46.000' N 164°14.000' W, 35 m, 23- V-1976, 2 specimens ( CAS 023887), Alaska Peninsula: off Cape Leontovich 55°47.000' N 162°10.000' W, 30 m, VI-1982, 3 specimens ( CAS 027777), Oregon: Coos County: Coos Bay: [43°21.276' N 124° 19.353 W], 200 specimens ( CAS 177200), 800 specimens, ( CAS 153583), California: San Francisco Bay: S.F. County: Alcatraz Island: shoal W of Alcatraz Island: 37°49.450' N 122° 25.917 W, 18.5 m, 24- IX-1973, 2 specimens ( CAS 1915), 37°49.270' N 122°25.550' W, 18,5 m, 04- VI-1974, 1 specimen ( CAS 1914), off Black Point: 37°48.467' N 122° 25.567 W, 7- VII-1972, 2 specimens ( CAS 149355), 37°48.467' N 122°25.567' W, 7- VII-1972, 1 specimen ( CAS 154071), Golden Gate: ship channel off Point Benita 37°48.000' N 122° 32.100 W, 32 m, 14- VIII-1973, 4 specimens ( CAS 123638), off Candlestick Point 37°42.500' N 122° 22.500 W, 7 VII-1972, 12 specimens ( CAS 141784), Monterey Bay: San Mateo County: 37°40.920' N 122°35.286' W, 26 m, fine sand, 13- IX-2007, 1 specimen ( ZMH P- 24845), 5 specimens ( ZMH P- 24846), 1 specimen ( ZMH P- 24847), 2 specimens ( ZMH P- 24848), Gulf of the Farallones 37°36.536' N 122° 32.023 W, 24.7 m, 22- IX-1997, 9 specimens ( CAS 157858), Los Angeles County: 3.35 miles bearing 112° true north from Point Vicente Light, 33°43.250' N 118°20.883' W, 20.1 m, coarse black sand, 24- V-1957, 22 specimens (LACM-AHF V5102), 3 specimens ( ZMH P- 25749); San Diego County: 7.15 miles off Point Loma lighthouse 32°32.750' N 117°15.750' W, 55.8 m, 14- VIII-1957, 2 specimens (LACM-AHF V5191-57), 9.5 miles off Point Loma lighthouse 32° 30.917' N 117°10.750' W, 29 m, 13-VIII-1957, 60 specimens (LACM-AHF V5187-57).

FIGURE 6. Spiophanes norrisi sp. nov.: A. Neuropodial hook with reduced hood from chaetiger 15, dorsal apical view. B. Chaetiger 8–12, lateral view; start of sabre chaetae on chaetiger 10 (indicated by arrow). C. Parapodium 8 and 9 with opening of glandular organ. D. Posteriormost chaetigers with stout, curved notochaeta (indicated by arrow). E. Micrograph of neuropodial chaetae in 14th chaetiger of specimen with body width of 0.42 mm, limbate capillaries together with single hook with reduced hood present. F. Chaetigers 8–12 with dorsal ciliated organs and dorsal ciliated ridges, dorsal view. — 2 specimens from California, Monterey Bay, depth 26 m, leg. D. Norris, Sep 2007 (A, B, D first specimen originally fixed in formalin, F second specimen originally fixed in ethanol). C ZMH –P14946, E LACM – AHF V5102; Scale: in µm.

SE Pacific Ocean: Chile (= part of type material of S. chilensis designated by G. Hartmann-Schröder): Punta Tortuga near Coquimbo [29°57.350' S 71°26.233' W], 120 m, 21- II-1960, 22 specimens ( ZMH P- 14946), Bahia Quillaipe [41°32.469' S 72°44.570' W], 1 m, sand, 21- I-1989, 2 specimens ( ZMH P- 21118).

Description. Holotype complete specimen 0.45 mm wide and about 14 mm in length. Paratypes between 0.2 and 0.6 mm wide.

Prostomium broad anteriorly, subtriangular, with long, digitiform anterolateral horns ( Fig. 5 A). Occipital antenna absent. Usually two pairs of black or red eyes present. Dorsal ciliated organs starting posterior to the prostomium as continuous ciliated bands to the end of chaetiger 2, thereafter as pair of segmental ciliated patches increasing in size, eventually becoming pairs of straight short ciliated bands until about chaetiger 8/9; after chaetiger 9 to about chaetiger 11 or 12 metameric ciliated patches comma-shaped and increasingly oblique in their orientation, from chaetigers 12–13 ciliated patches clearly oblique and almost transverse in chaetigers of the posterior body region; after application of Shirlastain A additional thin transverse cilia bands sometimes observed between metameric ciliated patches, in particular those in the posterior body region; metameric dorsal ciliated organs extending well into the abdominal region but not present on posteriormost chaetigers ( Figs. 5 A, 6F, Tab. 2). Peristomium moderately developed. First parapodium oriented dorsally; postchaetal lamellae subulate with slender tip, slightly longer in the notopodium than in the neuropodium ( Fig. 5 A). Parapodia of chaetigers 2–4 dorsolateral to lateral; postchaetal notopodial lamellae subulate, with slender tip; neuropodial postchaetal lamellae subtriangular ( Fig. 5 C). Chaetigers 5–8 with subulate notopodial and reduced neuropodial postchaetal lamellae ( Fig. 5 D). From chaetiger 9, notopodial postchaetal lamellae subulate with broad base and slender tip; neuropodial lamellae reduced ( Fig. 5 E).

Chaetal spreader of “0+1 type ” with undulate or almost semicircular glandular opening well developed on chaetigers 5, 7, and 8; on chaetiger 6 opening of glandular organ often reduced to a short slit; openings of glandular organs of chaetigers 9–(13)14 as lateral vertical slits, depending on start of neuropodial hooks ( Fig. 5 B, Fig. 6B, C). Ventrolateral intersegmental pouches absent. Dorsal ciliated crests present from chaetiger 3, moderately to well developed ( Figs 5 A, 6F).

Chaetiger 1 usually with one or two stout, crook-like chaetae in the neuropodium; remainder of chaetae all capillaries; notochaetae arranged in a tuft; neurochaetae in two rows. Chaetigers 2–4 with capillaries with narrow sheath ( Fig. 5 K) in the noto- and neuropodium; notochaetae in a tuft; neurochaetae in two rows. Notochaetae of chaetigers 5–14 capillaries with narrow sheaths, in three rows; neurochaetae stout sheathed capillaries, distally pointed ( Fig. 5 H), in 1–2 rows. Neuropodial hooks with partially reduced hood usually first present from chaetiger 14 in smaller individuals (body width <0.4 mm at chaetiger 4), larger specimens with neuropodial hooks from chaetiger 15 ( Fig. 8 right); hooks quadridentate, with main fang surmounted by single unpaired tooth and pair of smaller distal teeth (Fig. 6A), additional small teeth sometimes present; 4–10 hooks arranged in a single row, number depending on specimen size ( Fig. 9 ); notopodia with narrowly sheathed capillaries. Ventral sabre chaetae present from chaetiger 10 (rarely chaetiger 9) to end of body. Stout, curved notochaetae present in five to six posteriormost parapodia.

Pygidium usually with two thin, cirriform anal cirri; sometimes cirri basally split into two or more cirri.

Pigmentation. Orange-brown pigment may be present laterally on chaetigers of the middle body region and first few chaetigers of the posterior body region, usually starting on chaetiger 10, sometimes from chaetiger 9.

Methyl green staining pattern. Inconspicuous.

Biology. Planktonic larvae of Spiophanes cf. bombyx were found in Tomales Bay, California in November ( Blake 2006). The true identity of the observed larvae will remain uncertain but this observation might very well apply to S. norrisi sp. nov.

Remarks. S. norrisi sp. nov. is easily distinguished from all other Spiophanes species known from coastal waters of the eastern Pacific by its strikingly long anterolateral horns; the chaetal spreaders of “0+1 type ” with an undulate to almost semicircular opening well developed on chaetigers 5, 7, and 8; the dorsal ciliated organs starting as two short continuous bands extending to the end of chaetiger 2 followed by metameric patches in a species-specific pattern as described above; the first presence of sabre chaetae not earlier than chaetiger 10 (rarely 9); and the presence of partially hooded hooks in the neuropodia of the posterior body region. S. anoculata , a morphologically similar species, occurs in deep waters of the North Pacific Ocean, off California. S. anoculata is of smaller size, sabre setae start on chaetiger 4, and chaetal spreaders are fully developed on chaetigers 5–8 rather than 5, 7, and 8 as in S. norrisi . In addition, both species exhibit speciesspecific patterns of dorsal ciliated organs (for comparison see Tab. 2).

Differences between morphologically similar species from other geographic regions most importantly concern the orientation of the dorsal ciliated patches on chaetigers of the middle and posterior body region ( Tab. 2). S. norrisi is the only known member of this species complex with oblique orientation of metameric ciliated patches from early in the middle body region (from between chaetigers 9–10).

Intraspecific variation in S. norrisi includes the number of anal cirri and the shape of the opening of chaetal spreaders on chaetigers 5, 7, and 8. Usually two lateral anal cirri are present; however, sometimes the cirri are split into as many as three thin cirri. The presence of chaetal spreaders of “0+1 type ” with either an undulate or almost semicircular opening on anterior chaetigers of the middle body region seemed to depend on preservation: if bacillary fibres were exposed from inside the glandular organs or if the openings of the glandular organs were expanded, the shape of the opening tended to be more rounded (and hence described as rather semicircular than undulate).

The type material of Spiophanes chilensis Hartmann-Schröder, 1965 consisted of a holotype and several paratypes. Based on the holotype the species was found to be a junior synonym of Spiophanes duplex ( Chamberlin, 1919) by Meißner (2005). However, a single paratype of S. chilensis was identified as Spiophanes fimbriata Moore, 1923 whereas all other paratypes were identified as S. bombyx ( Claparède, 1870) by the same author at this time. These latter specimens were now investigated again in the course of this study and were found to belong to the newly described S. norrisi .

Etymology. The species is named after Dorothy Norris from San Francisco, who repeatedly provided specimens for morphological and genetic studies.

Geographical distribution. The species occurs from shallow waters up to subtidal depths waters along the North and South American coast.

Figures

FIGURE 5. Spiophanes norrisi sp. nov.: A. Anterior end, dorsal view; methyl green stained nuchal and dorsal ciliated organs. B. Anterior end, lateral view; methyl green stained openings of glandular organs on chaetigers 5, 7, and 8; arrow indicates simple vertical opening of glandular organ in chaetiger 14. C – F. Parapodium from chaetiger 2, 5, 11, and 19, all anterior view. G. Neuropodial hooks with reduced hood from chaetiger 19. H. Neuropodial chaeta from chaetiger 5. I. Sabre chaeta from chaetiger 11. K. Neuropodial chaeta from chaetiger 2. — B = LACM – AHF V. 1962 – 50 (Paratype); all others LACM – AHF V 5102. Scale: A, B 0.5 mm, C – F 0.1 mm. G – K 5 µm.

FIGURE 8. First presence of neuropodial hooks in relation to body width on chaetiger 4 in both Spiophanes bombyx and S. norrisi sp. nov.

FIGURE 9. Number of neuropodial hooks in relation to body width on chaetiger 4 in both Spiophanes bombyx and S. norrisi sp. nov.