Crucigera websteri

Invasion History

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

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General Invasion History:

The serpulid polychaete Crucigera websteri was first described from Apalachicola Bay, Florida. Its native range is in the Western Atlantic from South Carolina to northeast Brazil (ten Hove and Wolf 1984; US National Museum of Natural History 2008). It occasionally occurs in fouling communities on floats and pilings (ten Hove and Wolf 1984; Bastida-Zavala 2008). It has been introduced to the Eastern Pacific from California to Colombia, and was probably transported from the Atlantic by ships (Carlton 1979).

We currently regard C. websteri as an introduction to the Pacific, although future genetic analysis could alter this conclusion. Carlton (1979) considered C. websteri to be an Atlantic species introduced by fouling or ballast water to the Pacific. Ten Hove and Jansen-Jacobs (1984) found that Atlantic and Pacific specimens were morphologically indistinguishable and Bastida-Zavala (2008) calls this species 'Amphi-American'.

North American Invasion History:

Invasion History on the West Coast:

A specimen at the American Museum of Natural History was collected from 'California' in 1910 (Carlton 1979). In the 1940s, collections of C. websteri were made in southern California waters, at Santa Barbara Island and Newport Bay (Reish 1972, cited by Carlton 1979). An undated specimen was collected from San Pedro Bay and it was also found in Alamitos Bay (Reish 1972, cited by Carlton 1979). In fouling plate surveys in 2000-2003, only one specimen was found in California waters, in Humboldt Bay, the northernmost record for this species (Ruiz et al., unpublished data). We do not know of any other records from California waters since the 1970s.

Invasion History Elsewhere in the World:

Crucigera websteri is well-established on the Pacific Coast of Mexico, south to Ecuador.  There are recent records from the Gulf of California; the Pacific coast of Baja California; Puerto Escondido, Mexico; the Gulf of Panama; Colombia; and Ecuador (ten Hove and Wolf 1984; de Leon-Gonzalez 1990; Bastida-Zavala 2008; US National Museum of Natural History 2008).

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Description

Crucigera websteri secretes a calcareous tube, as do other serpulid polychaetes. Serpulids have a feathery crown of modified prostomial palps, called radioles (the prostomium is the first segment, projecting above the mouth). The radioles can be folded and withdrawn into the tube. One of the radioles is modified to form an operculum, which acts as a plug when the animal contracts. The peristomium (segment behind the mouth) is folded back to form a collar, which bears uniramous parapodia, with a distinctive set of collar chaetae, with spines or serrations. The collar is the first of seven thoracic chaeta-bearing segments (chaetigers). The subsequent segments have biramous parapodia. The dorsal branch of the parapodium is called the notopodium; the ventral is the neuropodium. Chaetae in the two branches, and along the body can vary greatly in their morphology, which can be critical in the taxonomy of serpulids (Description from: Barnes 1983; ten Hove and Jansen-Jacobs 1984; Blake and Ruff, in Carlton 2007; Bastida-Zavala 2008)

The tube of C. websteri is smooth, thin, and circular in cross-section. The tube may have meandering longitudinal keels (ten Hove and Jansen-Jacobs 1984), or can lack them (Bastida-Zavala 2008). The tubes lack peristomes (flared mouth) or alveoli (cavities). The diameter of the tube is usually about 2 mm, but may reach 3 mm. There are 14-26 pairs of branchial radioles, arranged in two nearly complete circles on either side of the mouth. The radioles are usually about 1/4 to 1/3 of the length of the animal, with some of the ventral-most being shorter. The operculum is shaped like a shallow funnel, lacks terminal spines, and is an almost bilaterally symmetrical, with four finger-like knobs below it. The operculum has 43-52 radii extending upwards and outwards, along the sides of the funnel, ending in rounded crenulations at the top. The collar is wide and three-lobed, with the medio-ventral lobe being longer. Some of the collar chaetae are bayonet-like, with 2 or 3 teeth at the base of the blade. Others are hair-like (limbate). Subsequent thoracic segments have hair-like capillary chaetae, and short, rasplike chaetae, called uncinae. The abdomen has up to 105 segments. The overall length of the worm may reach 20 mm. The operculum is white, while the gills are purplish-white, crimson, and orange, near the tips. (Description from: ten Hove and Jansen-Jacobs 1984; Blake and Ruff, in Carlton 2007; Bastida-Zavala 2008).

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Taxonomy

Ecology

General:

The serpulid polychaete Crucigera websteri feeds by extending its feathery gills, and trapping plankton in the water column, which are transported by cilia to the mouth (Barnes 1983). Specific information about the reproduction and life history of C. websteri is not available, but this species, like other serpulids, disperses by means of planktonic larvae. This species appears to be confined to marine salinities and relatively warm temperatures. It secretes a calcareous tube and can be found on hard surfaces such as rocks, pilings, shells, and corals.

Food:

Phtyoplankton, detritus

Trophic Status:

Suspension Feeder

SusFed

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Habitats

General Habitat	Marinas & Docks	None
General Habitat	Vessel Hull	None
General Habitat	Unstructured Bottom	None
General Habitat	Oyster Reef	None
Salinity Range	Polyhaline	18-30 PSU
Salinity Range	Euhaline	30-40 PSU
Tidal Range	Subtidal	None
Vertical Habitat	Epibenthic	None

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Tolerances and Life History Parameters

Maximum Length (mm)	20	ten Hove and Jansen-Jacobs 1984
Broad Temperature Range	None	Warm temperate-Tropical
Broad Salinity Range	None	Polyhaline-Euhaline

General Impacts

No economic or ecological impacts have been reported for Crucigera websteri in its introduced or native range.

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References

Barnes, Robert D. (1983) Invertebrate Zoology, Saunders, Philadelphia. Pp. 883

Bastida-Zavala, J. Rolando. (2008) Serpulids (Annelida: Polychaeta) from the Eastern Pacific, including a brief mention of Hawaiian serpulids., Zootaxa 1722: 1-61

Blake, James A.; Ruff, R. Eugene (2007) The Light and Smith Manual: Intertidal invertebrates from Central California to Oregon (4th edition), University of California, Berkeley CA. Pp. 309-410

Blakeslee, April M. H.; Miller, A. Whitman; Ruiz, Gregory M.; Kerstin Johannesson · Carl André ·Johannsson, Kerstin;· André, Carl; Panova, Marina (2021) Population structure and phylogeography of two North Atlantic Littorina species with contrasting larval development, Marine Biology 168: <missing location>

Carlton, James T. (1979) History, biogeography, and ecology of the introduced marine and estuarine invertebrates of the Pacific Coast of North America., Ph.D. dissertation, University of California, Davis. Pp. 1-904

Carlton, James T. (Ed.) (2007) The Light and Smith Manual: Intertidal Invertebrates from Central California to Oregon Fourth Edition, Completely Revised and Expanded, University of California Press, Berkeley. Pp. <missing location>

de Leon-Gonzalez, Jesus Angel (1990) Dos serpulidos nuevos para el pacifico mexicano y duplicidad opercular en Hydroides crucigerus., Revue Biological Tropicale 38 (2A): 335-338

Dean, Harlan K. (2009) Marine Biodiversity of Costa Rica, on attached CD Springer, Berlin. Pp. Table 13.2

Hartman, Olga (1969) <missing title>, Allan Hancock Foundation, Los Angeles. Pp. <missing location>

Lewis, John A.; Watson, Charlotte; ten Hove, Harry A. (2006) Establishment of the Caribbean serpulid tubeworm Hydroides sanctaecrucis Krøyer [in] Morch, 1863, in northern Australia., Biological Invasions 8: 665-671

ten Hove, H. A.; Jansen-Jacobs, M. J. (1984) Proceedings of the First International Polychaete Conference, Sydney 1983, The Linnean Society of New South Wales, Syndne. Pp. 143-180

Ten Hove, Harry A.; Wolf, P.S. (1984) Family Serpulidae Johnston, 1865. Chapter 55, In: None(Eds.) Taxonomic guide to the polychaetes of the Gulf of Mexico. , Mobile. Pp. 55-1 to 55-34

U.S. National Museum of Natural History 2002-2021 Invertebrate Zoology Collections Database. http://collections.nmnh.si.edu/search/iz/



Wesselingh, Frank P. and 20 authors (2019) Mollusc species from the Pontocaspian region- an expert opinion list, ZooKeys 824: 31-124

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