Sternaspis affinis

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Sendall K, Salazar-Vallejo S (2013) Revision of Sternaspis Otto, 1821 (Polychaeta, Sternaspidae). ZooKeys 286 : 1–74, doi. Versioned wiki page: 2013-04-08, version 33073, , contributors (alphabetical order): Pensoft Publishers.

Citation formats to copy and paste


author = {Sendall, Kelly AND Salazar-Vallejo, Sergio I.},
journal = {ZooKeys},
publisher = {Pensoft Publishers},
title = {Revision of Sternaspis Otto, 1821 (Polychaeta, Sternaspidae)},
year = {2013},
volume = {286},
issue = {},
pages = {1--74},
doi = {10.3897/zookeys.286.4438},
url = {},
note = {Versioned wiki page: 2013-04-08, version 33073, , contributors (alphabetical order): Pensoft Publishers.}


RIS/ Endnote:

T1 - Revision of Sternaspis Otto, 1821 (Polychaeta, Sternaspidae)
A1 - Sendall K
A1 - Salazar-Vallejo S
Y1 - 2013
JF - ZooKeys
JA -
VL - 286
IS -
UR -
SP - 1
EP - 74
PB - Pensoft Publishers
M1 - Versioned wiki page: 2013-04-08, version 33073, , contributors (alphabetical order): Pensoft Publishers.

M3 - doi:10.3897/zookeys.286.4438

Wikipedia/ Citizendium:

<ref name="Sendall2013ZooKeys286">{{Citation
| author = Sendall K, Salazar-Vallejo S
| title = Revision of Sternaspis Otto, 1821 (Polychaeta, Sternaspidae)
| journal = ZooKeys
| year = 2013
| volume = 286
| issue =
| pages = 1--74
| pmid =
| publisher = Pensoft Publishers
| doi = 10.3897/zookeys.286.4438
| url =
| pmc =
| accessdate = 2019-07-17

}} Versioned wiki page: 2013-04-08, version 33073, , contributors (alphabetical order): Pensoft Publishers.</ref>

See also the citation download page at the journal.


Ordo: Canalipalpata
Familia: Sternaspidae
Genus: Sternaspis


Sternaspis affinis Stimpson, 1864, emendedWikispecies linkPensoft Profile

  • Sternaspis affinis Stimpson, 1864: 159; von Marenzeller 1890[1]: 5–8, Pl. 1, fig. 7.
  • Sternaspis fossor: Treadwell 1914[2]: 215; Chamberlin 1919[3]: 405–406; Moore 1923[4]: 21; Berkeley 1930[5]: 69; Berkeley and Berkeley 1941[6]: 19 (list), 51; 1952[7]: 59–60, fig. 123; Hartman 1963[8]: 59, 1969[9]: 351–352, fig. 1; Fauchald 1972: 238–239 (partim); Bilyard and Carey 1979[10]: fig. 2, Tab. 2, 1980[11]: 22; Fauchald and Hancock 1981[12]: 35 (non Stimpson 1853[13]).
  • Sternaspis fossor? : Moore 1908[14]: 358.
  • Sternaspis scutata: Hartman and Reish 1950[15]: 38; Pettibone 1954[16]: 309–310, fig. 35 a, b (partim); Fauchald 1077[17]: 113, fig. 33C, D; Hobson and Banse 1981[18]: 18, 19, 63, Tab. 3, fig. F (non Ranzani 1817[19]).

Type material

Canada, British Columbia, Strait of Georgia. Neotype (RBCM 005-138-001), and 15 paraneotypes (RBCM 005-138-002), 49°10'47"N, 123°18'02"W, 80 m, 13-III-2003.
Additional material. Canada, British Columbia. 2 spec. (LACM n2939), Departure Bay, mud and rocks, 18-VII-1940, G.E. & N. MacGinitie, coll. 1 spec. (NHMW 1565), Vancouver Island, 1875. 34 spec. (RBCM 987-254-023), Vancouver Island, southwest of Cape Beale, 48°35'54"N, 125°08'24"W, 104 m, 23-VII-1987. 17 spec. (RBCM 002-148-001), Vancouver Island, Trevor Channel, Helby Island, 48°50'00"N, 125°10'00"W, 19-VI-2002. 1 spec. (RBCM 996-148-004), Vancouver Island, Nanoose Bay, 49°15'30"N, 124°08'30"W, 28 m, 4-VI-1996. 3 spec. (RBCM 991-924-006), Vancouver Island, Saanich Inlet, 48°42'36"N, 123°31'00"W, 60–70 m, 16-II-1987. 24 spec. (RBCM 988-9-032), Dixon Entrance, west of Dundas Island, 54°29'40"N, 131°11'01"W, 143 m, 23-I-1988. Four spec. (RBCM 990-320-043), Vancouver Island, southwest of Nootka Sound, 49°25'14"N, 127°21'55"W, 1000–1166 m, 3-II-1990. U.S.A., Alaska. 2 spec. (CAS 151054), Boca de Quadra Inlet, III-1981. 12 spec. (CAS 17805), Gulf of Alaska, Cook Inlet, 59°34'54"N, 151°30'24"W, 99 m, 22-X-1976. 4 spec. (CAS 18987), Chukchi Sea, 67°15'N, 165°25'W, 33 m, 11-IX-1907. 2 spec. (USNM 63142), Gulf of Alaska, 59°51'30"N, 142°06'50"W, 53–100 m, 11-VII-1976. Washington. 4 spec. (RBCM 985-474-001), west of Cape Flattery, 48°25'24"N, 125°14'00"W, 168 m, 18-VI-1985. Oregon. 8 spec. (USNM 74917), mouth of Columbia River, 91 m, 15-IX-1961. California. 20 spec. (ANSP 3315), Monterey Bay, 66 m, 13-V-1904. Mexico, Gulf of California. 2 spec. (SIO A838), Isla Angel de Ia Guarda, 562–642 m, 18-I-1968. 16 spec. (SIO A839), Isla Angel de Ia Guarda, 1474 m, 18-I-1968.


Neotype (RBCM 005-138-001), with body cream to light tan, sometimes greyish (Fig. 5A, B). First six segments smooth with a few minute cuticular papillae widely and evenly spaced. Remaining segments more papillate and opaque in appearance. Segments seven and eight slightly more opaque and dense than preceding ones, with stout cuticular papillae especially near genital papillae, some cuticular papillae with small grains of sediment adhered to bases. Body 15.5 mm long, 5.0 mm wide (other specimens up to 22 mm long, 7 mm wide), about 29 segments.
Prostomium hemispherical, opalescent, translucent, sometimes with crescent shaped red eyespots laterally on smaller individuals (Fig. 5C, insert). Peristomium round, without papillae. Mouth oval, covered by papillae, extending from base of prostomium to anterior edge of second segment.
First three chaetigers with 8–14 light bronze, widely separated, slightly falcate introvert hooks per bundle, each with subdistal dark areas (Fig. 5C). Genital papillae protrude ventrolaterally from intersegmental groove between segments 7 and 8.
Pre-shield region with 7 segments, with papillae evenly spaced, slightly denser than on anterior segments, although less so ventrally, and in single rows of clusters of short filaments closer to ventro-caudal shield, especially on dorsal surface, rarely showing delicate short capillary chaetae protruding laterally from body wall.
Ventro-caudal shield with concentric lines, slightly ribbed; suture extended throughout shield (restricted to the anterior region in larger specimens). Anterior margins rounded; anterior depression deep; anterior keels not exposed (Figs 1B, 2, 5B, D). Lateral margins gently rounded (straighter in larger specimens), not expanding posteriorly. Fan truncate, almost straight in juveniles, sometimes with median notch, becoming crenulated in larger specimens.
Marginal chaetal fascicles include 10 lateral ones (Fig. 5E), chaetae ovally arranged, and five posterior fascicles, chaetae in a linear arrangement. Peg chaetae on conical extensions emerging under most prominent oblique rib of the shield. Peg chaetae with stout base in cross section; a small fascicle of delicate capillary chaetae (peg-associated capillary chaetae) between peg chaetae and first fascicle of posterior chaetae.
Branchiae numerous, thick, coiled, slender, long, protruding from two oval plates, separated by a wide angle, on either side of anus. Additional fine, long filamentous papillae extending to lateral and posterior margins of shield.

Neotype locality

British Columbia, Canada, Strait of Georgia.


It appears that Sternaspis affinis has not been reported since 1875. However, many collections hold specimens collected over the last hundred years of what appears to be the only species present along the northeast Pacific coast of North America, from the Beaufort Sea to California, and into the Gulf of California. These have been labelled either as Sternaspis scutata or Sternaspis fossor.
The original description by Stimpson is brief and only includes a scant comparison of the cuticle with the Atlantic species, Sternaspis fossor. As Stimpson’s description agrees with the characters of the specimens found along the northeast Pacific coast, we propose the emendation above with the designation of a neotype.
The taxonomic status of Sternaspis affinis Stimpson, 1864 needs clarification because it has been regarded as a junior synonym of a Northwestern Atlantic species, Sternaspis fossor Stimpson, 1853, or of the Mediterranean species, Sternaspis scutata (Ranzani, 1817). The proposal of a neotype together with the above description and illustrations will clarify the current situation (ICZN 1999[20], Art. 75.3.1–75.3.3). The original material was deposited in the Smithsonian and later transferred to Chicago when William Stimpson was appointed director of the local Academy of Sciences in 1866, but they were destroyed in 1871 during the great Chicago fire (; ICZN 1999[20], Art. 75.3.4). Despite the fact that the original description was brief, Sternaspis affinis seems to be the only species living in the type locality region, and we are confident that the neotype corresponds to the species (ICZN 1999[20], Art. 75.3.5). The proposed neotype was collected in the type locality (ICZN 1999[20], Art. 75.3.6), and it has been deposited in the Royal British Columbia Museum (ICZN 1999[20], Art. 75.3.7).
Sternaspis affinis resembles Sternaspis fossor, Sternaspis maior and Sternaspis islandica as they all have shields with rounded anterior margins, lateral margins slightly rounded, and posterior margins reaching or slightly expanded beyond the posterolateral corners. However, Sternaspis islandica differs by having a very shallow anterior depression, whereas the two other species have deep anterior depressions. The remaining three species differ because in Sternaspis affinis and Sternaspis maior the radiating ribs and posterior corners are often distinct, whereas they are barely developed, or not at all in Sternaspis fossor. Therefore, Sternaspis affinis is very similar to Sternaspis maior but their main difference lies in the relative development of concentric lines which are distinct in Sternaspis affinis and not visible or barely visible in Sternaspis maior.


Alaska, USA (in the Gulf of Alaska) south along the coast and inland waters to Monterey, California, USA, and into the Gulf of California. This species, identified as Sternaspis fossor, has been regarded as one of the most abundant ones along the coast in the East Sound of the San Juan Islands (Weese and Macnab 1930[21]), and along the Washington coast in 95–154 m with sediment having 50–68% mud (Lie and Kisker 1970[22]). Moore (1923[4]: 218) reported two species from Southern California, based upon the number of chaetal fascicles along the shield margins; one with 16 total bundles found in 441–492 m, and the other, smaller in size, with 15 total bundles and collected in sediments at 92–1190 m.

Taxon Treatment

  • Sendall, K; Salazar-Vallejo, S; 2013: Revision of Sternaspis Otto, 1821 (Polychaeta, Sternaspidae) ZooKeys, 286: 1-74. doi


Other References

  1. 1.0 1.1 von Marenzeller E (1890) Annulaten des Beringmeeres. Annalen des Kaiserliche Naturhistorische Hofmusem, Wien 5: 1-18.
  2. Treadwell A (1914) Polychaetous annelids of the Pacific coast in the collection of the Zoological Museum of the University of California. University of California Publications in Zoology 13 (8): 175-234.
  3. Chamberlin R (1919) The Annelida Polychaeta. Memoirs of the Museum of Comparative Zoology, Harvard College 48: 1–514 + 80 pls.
  4. 4.0 4.1 Moore J (1923) The polychaetous annelids dredged by the USS “Albatross” off the coast of southern California in 1904: 4. Spionidae to Sabellariidae. Proceedings of the Academy of Natural Sciences of Philadelphia 75: 179-259.
  5. Berkeley E (1930) Polychaetous annelids from the Nanaimo District, Part 5. Ammocharidae to Myzostomidae. Contributions to Canadian Biology and Fisheries 6 (5): 67-77.
  6. Berkeley E, Berkeley C (1941) On a collection of Polychaeta from southern California. Bulletin of the Southern California Academy of Sciences 40 (1): 16-60.
  7. Berkeley E, Berkeley E (1952) Canadian Pacific Fauna, 9. Annelida, 9b(2). Polychaeta Sedentaria. Univeristy of Toronto Press, 139 pp.
  8. Hartman O (1963) Submarine Canyons of Southern California, 3. Systematics: Polychaetes. Allan Hancock Pacific Expeditions 27 (3): 1-93.
  9. Hartman O (1969) Atlas of the sedentariate polychaetous annelids from California. Los Angeles, California, Allan Hancock Foundation, University of Southern California, Los Angeles, 812 ppp.
  10. Bilyard G, Carey A (1979) Distribution of western Beaufort Sea polychaetous annelids. Marine Biology 54: 329-339. doi: /10.1007/BF00395439
  11. Bilyard G, Carey A (1980) Zoogeography of western Beaufort Sea Polychaeta (Annelida). Sarsia 65: 19-26.
  12. Fauchald K, Hancock D (1981) Deep-water polychaetes from a transect off central Oregon. Allan Hancock Foundation Monographs 11: 1-73.
  13. Stimpson W (1853) Synopsis of the marine Invertebrata of Grand Manan: or the region abou the mouth of the Bay of Fundy. Smithsonian Contributions to Knowledge 6: 5–67. [printed and distributed in March, 1853]
  14. Moore J (1908) Some polychaetous annelids of the northern Pacific coast of North America. Proceedings of the Academy ofNatural Sciences of Philadelphia 60: 321-364.
  15. Hartman O, Reish D (1950) The marine annelids of Oregon. Oregon State College Monographs, Studies in Zoology 6: 1-64.
  16. Pettibone M (1954) Marine polychaete worms from Point Barrow, Alaska, with additional records from the Atlantic and North Pacific. Proceedings of the United States National Museum 103: 203-356. doi: 10.5479/si.00963801.103-3324.203
  17. Fauchald K (1977) The Polychaete Worms. Definitions and keys to the orders, families and genera, Natural History Museum of Los Angeles County Science Series 28: 1-190.
  18. Hobson K, Banse K (1981) Sedentariate and archiannelid polychaetes of British Columbia and Washington.Canadian Bulletin of Fisheries and Aquatic Sciences 209: 8 + 144.
  19. Ranzani C (1817) Descrizione di una nuova specie del genere Thalassema. Opuscoli scientifica 2, 112, Oken’s Isis 12–13(183): 1457–1461. [transl. German with additional comments in 1817]
  20. 20.0 20.1 20.2 20.3 20.4 ICZN ( (1999) International Code of Zoological Nomenclature, 4th ed. International Trust for Zoological Nomenclature (The Natural History Museum), London, 306 pp. []
  21. Weese A, Macnab J (1930) Seral communities of a muddy sea bottom. Proceedings of the Oklahoma Academy of Sciences 10: 26-28.
  22. Lie U, Kisker D (1970) Species composition and structure of benthic infauna communities off the coast of Washington. Journal of the Fisheries Research Board of Canada 27: 2273–2285. doi: 10.1139/f70-255
  23. Uschakov P (1955) Polychaeta of the Far Eastern Seas of the USSR. Israel Program for Scientific Translations, Jerusalem (transl. 1965), 26 + 419.