Invasion History

First Non-native North American Tidal Record: 1936
First Non-native West Coast Tidal Record: 1936
First Non-native East/Gulf Coast Tidal Record:

General Invasion History:

Heteromastus filiformis was described by Claparede in 1864 from Port-Vendres, on the Mediterranean coast of France, and later re-examined by Eisig, near Genoa, Italy in 1887. It was subsequently found on the East Coast of the US from Maine to North Carolina in the 1870s-80s (Hutchings and Rainier 1982). This worm has been reported in muddy-silty sediments on the coasts of every continent, except Antarctica. It spans Arctic and tropical waters, from the upper intertidal to the abyssal zone and from 5-40 PSU (Hartman 1947; Wolff 1973; Hartmann-Schroder 1980; Dean 2011; Weslawski et al. 2012; de Kluijver et al. 2014). Very likely 'H. filiformis’ represents a complex of cryptic species, similar to those found in its cosmopolitan relative, Capitella capitata (Eckelbarger and Grassle 1987).

However, the relatively recent collections and apparent spread of Heteromastus filiformis on the West Coast of North America, well after the onset of invertebrate collections, suggests that this polychaete has been introduced. It was first collected in San Francisco Bay in 1936, and found in harbors and bays from British Columbia (1st record 1962, Berkeley 1966) to Morro Bay (1st record 1960, Reish and Barnard 1967). Possible vectors include transport of larvae, or suspended adults in ballast water, and transport with plantings of Eastern Oysters (Crassostrea virginica). Occurrences in Prince William Sound, Alaska, may be the result of transport by shipping (1st record 1972, Hines et al. 2000), while deep water collections in the Bering Sea probably represent native Arctic cryptic species (US National Museum of Natural History 2015).

North American Invasion History:

Invasion History on the West Coast:

Heteromastus filiformis was first collected on the West Coast in San Francisco Bay, California (CA) in 1936 (Hartman 1947). It occurs at high densities in the central, South, and San Pablo Bays, and inland as far as Pittsburg, Suisun and Grizzly Bay (Carlton 1979; Nichols and Thompson 1985a; Nichols and Thompson 1985b; Peterson and Vayssieres 2010; California Academy of Sciences 2015). In 1962, this polychaete was collected at 24 m depth off Comox, Vancouver Island, in the Strait of Georgia (Berkeley 1966). Subsequent collections were made at Grays Harbor, Washington (1st record 1977, Albright and Smith 1977, cited by Carlton 1979); the Columbia River estuary (before 2002, Systsma et al. 2004); Coos Bay, Oregon (1st record 1970, Carlton 1989; Wonham and Carlton 2005); and Humboldt Bay, CA (2000, Boyd et al. 2002). More recently, it was collected in Southern California (Mission Bay and /Los Angeles-Long Beach Harbor in 2011 (California Department of Fish and Wildlife 2014).

However, specimens of 'Heteromastus filiformis' were collected in Alaskan offshore waters in the Bering Sea, near the Pribilof Islands at 135 m in 1976 (USNM 63505-63509, US National Museum of Natural History 2015), and in deep waters (524 m) off California (1988, USNM 123124, US National Museum of Natural History 2015). These deep water specimens presumably represent native Arctic or deep water members of the H. filiformis species complex. Specimens identified as H. filiformis occur in the Arctic Ocean, off Svalbard, down to 900m (Weslawski et al. 2012).

Invasion History Elsewhere in the World:

Heteromastus filiformis has been considered native or cryptogenic over much of its range. Introductions in ballast water, fouling, dry ballast, or with oysters are possible; however, given its small size, burrowing habitat, and paucity of distinguishing morphological features, it is likely that a number of cryptic species occupy its nominal range. Early records for Australia and New Zealand are 1969 in Port Philip Bay, Victoria (Hutchings and Rainier 1982) and 1976 in Hawke Bay, New Zealand (Knox and Fenwick 1981).


Description

Heteromastus filiformis is probably a complex of cryptic species belonging to the Capitellidae family. They lack protostomial or peristomial appendages, with branchiae absent or greatly reduced. The body has a distinct protostome, a thoracic version with a fixed number of segments, and a variable number of abdominal segments. Capitellids as a group are among the most abundant polychaetes in soft-bottom communities (Hartman 1947; Blake and Ruff 2007).

The body of H. filiformis is slender and fragile. The prostomium is small and conical, without eyespots or appendages. The thorax consists of 11 chaetigers and is slightly inflated anteriorly. Chaetigers 1-5 have capillary chaetae, while 6-11 have hooded hooks. The abdominal chaetae are all hooded hooks. From chaetigers 90-100, posteriorly, there are pairs of small, single, finger-like branchiae on each segment. The pygidium has a long, pointed terminal process. Specimens from the UK reach about 100 mm and have 140 segments (Hayward and Ryland 1990); specimens from the North Sea are about 180 mm with 150 segments; and specimens from the US East Coast are about 40 mm with 230 segments (Hutchings and Rainier 1982). Some of this size variation could be due to effects of preservation. The anterior region is dull red, while the posterior is reddish-yellow or greenish. Description based on: Hartman 1947, Hutchings and Rainier 1982, Hayward and Ryland 1990, Blake and Ruff 2007, and de Kluijver et al. 2014.

Limited comparative studies looking at the morphology, life history and genetics of H. filiformis populations have been conducted, to our knowledge. Hutchings and Rainier (1982) compared some populations and found no consistent morphological differences between specimens from Europe, the US East Coast, and Australia. Given the wide climate, habitat, and salinity range of records of H. filiformis, sibling speciation is likely. Molecular studies are needed to untangle the taxonomy, biogeography, and invasion history of the H. filiformis complex.

Morphology and development of H. filiformis larvae from Passamaquoddy Bay, New Brunswick are illustrated by Lacalli (1980).


Taxonomy

Taxonomic Tree

Kingdom:   Animalia
Phylum:   Annelida
Class:   Polychaeta
Order:   Capitellida
Family:   Capitellidae
Genus:   Heteromastus
Species:   filiformis complex

Synonyms

Capitella filiformis (Claparede, 1864)
Notomastus filiformis (Verrill, 1873)
Areniella filiformis (Verrill, 1874)
Ancistria minima. (Webster, 1879)
Notomastus laevis (Webster, 1886)
Heteromastus filiformis (Eisig, 1887)

Potentially Misidentified Species

Heteromastus filobranchus
This capitlellid has multiple fine branchiae radiating out from its abdominal chaetifgers (Hartman 1947).

Mediomastus ambiseta
Juvenile Heteromastus filiformis have hooded hooks on chaetigers 4 and 5, and can be confused with Mediomastus spp. The hooded hooks are later replaced by capillary chaetae (Fredette 1982).

Mediomastus californiensis
Juvenile Heteromastus filiformis have hooded hox on chaetigers 4 and 5, and can be confused with Mediomastus spp. The hooded hooks are later replaced by capillary chaetae (Fredette 1982).

Ecology

General:

'Heteromastus filiformis' is a complex of cryptic species, found over a wide range of depth, climate, and salinity. Different populations are likely to vary in life history and environmental tolerances (Nygren 2014). Caution is advisable in generalizing information across regions. In European and Gulf of Maine populations, eggs are laid in gelatinous capsules on the sediment surface. Larvae are planktonic and planktotrophic (Lacalli 1980; Shaffer 1983). Larvae from Passamaquoddy Bay (Gulf of Maine) settled in ~17-18 days after hatching with ~11 setigers, at 400 μm length (Lacalli 1980).  Adults in populations in North Inlet, South Carolina, lived for at least 2 years (Shaffer 1983).

'Heteromastus filiformis has been reported from Arctic, temperate, subtropical and tropical seas. West Coast populations are known from shallow estuaries and mudflats, and probably tolerate a wide temperature range (Nichols and Thompson 1985b; Hopkins 1986). In the Rhine Delta, Netherlands, 'H. filiformis' occurs at salinities as low as 5 PSU, but is much more common at salinities above 18 PSU (Wolff 1973). In the San Francisco estuary, this worm is common as far upstream as Grizzly Bay in dry years, at 5-10 PSU, but is more abundant in San Pablo Bay (Peterson and Vaysieres 2010). 'Heteromastus filiformis' is a head-down burrower, preferring muddy sediments, though it also occurs in fine and median sand (Wolff 1973; Quintana et al, 2007). It is a deposit-feeder, and can burrow up to 15 cm beneath the sediment surface. The worm ventilates its burrow, and the oxygenated water in the burrow allows the worms to penetrate for some distance into anoxic sediments. Feeding is believed to be non-selective, on microalgae, detritus, and other organic particles (Wolff 1973). Fecal pellets are deposited on the sediment surface (Quintana et al. 2007). 'Heteromastus filiformis' often reaches high abundances, and is potentially an important food item for benthic invertebrates and fishes. However, caging experiments, in North Inlet, South Carolina, suggested that excluding large predators had no effect on this species density (Shaffer 1982).

Food:

Detritus

Trophic Status:

Deposit Feeder

DepFed

Habitats

General HabitatGrass BedNone
General HabitatUnstructured BottomNone
General HabitatSalt-brackish marshNone
Salinity RangeMesohaline5-18 PSU
Salinity RangePolyhaline18-30 PSU
Salinity RangeEuhaline30-40 PSU
Tidal RangeSubtidalNone
Tidal RangeLow IntertidalNone
Vertical HabitatEndobenthicNone


Tolerances and Life History Parameters

Minimum Salinity (‰)5Field, But uncommon, below 18 PSU, Netherlands (Wolff 1973)
Maximum Salinity (‰)40average Red Sea salinity (Wehe and Fiege 2002)
Maximum Duration18 Larvae from Passamaquoddy Bay (Gulf of Maine) settled in ~17-18 days after hatching (Lacalli 190). Wolff (1973) gave an estimated planktonic larval duration of 10 days for worms from the Netherlands, based on filed data.
Maximum Length (mm)180Hutchings and Rainer (1982). The pygidium has a long, pointed terminal process. Specimens from the UK reach about 100 mm and have 140 segments (Hayward and Ryland 1990); specimens from the North Sea are about 180 mm with 150 segments; and specimens from the US East Coast are about 40 mm with 230 segments (Hutchings and Rainier 1982). Some of this size variation could be due to effects of preservation.
Broad Temperature RangeNoneCold temperate-Tropical
Broad Salinity RangeNoneOligohaline-Euhaline

General Impacts

Capitellid polychaetes, including Heteromastus filiformis, are an important component of infaunal communities, burrowing and reworking sediments, and increasing the oxygen penetration (Wolff 1973; Quintna et al. 2007). They are a potentially important food source for benthic predators. However, the specific impacts of H. filiformis are difficult to determine, since it coexists with many other native and cryptogenic capitellid polychaetes (Hartman 1947; Blake and Ruff 2007).

Regional Distribution Map

Bioregion Region Name Year Invasion Status Population Status
NEP-VI Pt. Conception to Southern Baja California 2011 Non-native Established
P030 Mission Bay 2011 Non-native Established
P050 San Pedro Bay 2011 Non-native Established
P130 Humboldt Bay 2000 Non-native Established
P080 Monterey Bay 1977 Non-native Established
NEP-IV Puget Sound to Northern California 1970 Non-native Established
P095 _CDA_P095 (Tomales-Drakes Bay) 1969 Non-native Established
P070 Morro Bay 1960 Non-native Established
P093 _CDA_P093 (San Pablo Bay) 1936 Non-native Established
NEP-V Northern California to Mid Channel Islands 1936 Non-native Established
P090 San Francisco Bay 1936 Non-native Established

Occurrence Map

OCC_ID Author Year Date Locality Status Latitude Longitude
755700 Introduced Species Study 2003 2003-08-27 Corinthian Marina 2 Non-native 37.8720 -122.4556
755701 Introduced Species Study 2003 2003-08-27 Loch Lomond 2 Non-native 37.9717 -122.4811
755702 Introduced Species Study 2005 2005-06-07 Oakland Inner Harbor - Small marinas Non-native 37.7847 -122.2669
755703 Introduced Species Study 2005 2005-06-07 Port of Oakland Office Non-native 37.7954 -122.2804
755704 Introduced Species Study 2005 2005-06-08 Oakland Outer Harbor Non-native 37.8217 -122.3145
755705 Introduced Species Study 2005 2005-06-08 Sea Plane Lagoon Non-native 37.7761 -122.2998
755706 Introduced Species Study 2005 2005-06-09 Paradise Area Non-native 37.9062 -122.4768
755707 Introduced Species Study 2005 2005-06-09 Richardson Bay Non-native 37.8588 -122.4798
755708 Introduced Species Study 2005 2005-06-10 Hayward Landing Non-native 37.6447 -122.1543
755709 Introduced Species Study 2005 2005-06-10 Toll Plaza Non-native 37.8266 -122.3166
755710 Introduced Species Study 2005 2005-08-25 Ferry Terminal Pier Non-native 37.7945 -122.3917
755711 Introduced Species Study 2005 2005-09-07 Redwood Creek - Marina Non-native 37.5021 -122.2130
755712 Introduced Species Study 2005 2005-09-07 Redwood Creek - Shipping Non-native 37.5120 -122.2109
755713 Introduced Species Study 2005 2005-09-09 Coyote Point Marina Non-native 37.5905 -122.3177
755714 Introduced Species Study 2005 2005-09-09 San Mateo Bridge Non-native 37.5806 -122.2543
755715 Introduced Species Study 2005 2005-09-09 Sierra Point Marina Non-native 37.6740 -122.3792
755716 Introduced Species Study 2005 2005-10-06 Santa Fe Channel - Back Non-native 37.9207 -122.3684
755717 Introduced Species Study 2005 2005-10-19 Hercules Wharf Non-native 38.0231 -122.2928
755718 Introduced Species Study 2005 2005-10-19 Mare Island Strait - Marina Non-native 38.1051 -122.2667
755719 Introduced Species Study 2005 2005-10-20 Port Sonoma/Petaluma R. Non-native 38.1157 -122.5026
755720 Introduced Species Study 2005 2005-10-20 San Pablo Bay Pumphouse Non-native 38.0446 -122.4326
755721 Introduced Species Study 2005 2005-10-21 Ayala Cove Non-native 37.8680 -122.4350
755722 Introduced Species Study 2010 2010-06-13 Hayward Landing Non-native 37.6447 -122.1543
755723 Introduced Species Study 2010 2010-07-01 Corinthian Marina Non-native 37.8726 -122.4563
755724 Introduced Species Study 2011 2011-04-20 Slip D-50 Non-native 33.7165 -118.2801
755725 Introduced Species Study 2011 2011-05-04 Seaforth Non-native 32.7621 -117.2365
758921 Hartman 1947 1936 San Francisco Bay Non-native 37.8494 -122.3681
758922 Hartman 1954 1954 San Pablo Channel Non-native 37.9698 -122.4385
758923 Reish and Barnard 1967 1960 1960-08-25 Morro Bay Non-native 35.3500 -120.8500
758924 Jones 1961 1955 Point Richmond, Station A Non-native 37.9211 -122.3881
758925 Jones 1961 1955 Point Richmond, Station B Non-native 37.9114 -122.3889
758926 Jones 1961 1955 Point Richmond, Station C Non-native 37.9036 -122.3853
758927 Light 1969 1967 Bolinas Lagoon Non-native 37.9189 -122.6816
758928 Chapman and Dorman 1975 1972 1972-03-19 Tubbs Island, NE side Non-native 38.1256 -122.4367
758929 Nybakken et al. 1977 1974 Station N-2, offshore of Moss Landing Harbor Non-native 36.8144 -121.7992
758930 Nybakken et al. 1977 1975 1975-09-16 Station N-2, offshore of Moss Landing Harbor Non-native 36.8144 -121.7992
758931 Nybakken et al. 1977 1975 1975-04-02 Station N-4, offshore of Moss Landing Harbor Non-native 36.8099 -121.8094
758932 Nybakken et al. 1977 1976 1976-06-15 Beach in front of original Moss Landing Marine Laboratories site (Station 11-1B) Non-native 36.8002 -121.7897
758933 Nichols and Thompson 1985a 1985 San Pablo Bay Non-native 38.0600 -122.3900
758934 Nichols and Thompson 1985a, 1985b 1985 Sand Point, Palo Alto Non-native 37.4630 -122.1011
758935 Boyd et al. 2002 (Humboldt Bay Report) 2002 Bracut Non-native 40.8313 -124.0845
758936 Boyd et al. 2002 (Humboldt Bay Report) 2002 Eureka Channel HB, St. 21 Non-native 40.8063 -124.1666
758937 Boyd et al. 2002 (Humboldt Bay Report) 2002 Hilfiker Road Non-native 40.7720 -124.1960
758938 Boyd et al. 2002 (Humboldt Bay Report) 2002 Jacoby Creek Non-native 40.8435 -124.0838
758939 Boyd et al. 2002 (Humboldt Bay Report) 2002 Klopp Lake Non-native 40.8553 -124.0919
758940 Boyd et al. 2002 (Humboldt Bay Report) 2002 Mad River Slough - Samoa Blvd. Bridge Non-native 40.8652 -124.1505
758941 Cohen et al. 2005 (SF Bay Area RAS) 2004 2004-05-28 Rodeo Marina, San Pablo Bay Non-native 38.0391 -122.2711
758942 Heiman and Micheli 2010; Hobbs et al. 2015 2002 Elkhorn Slough (Upper) Non-native 36.8547 -121.7600

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