Hydroides gairacensis

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:

None

North American Invasion History:

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Description

Hydroides gairacensis 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 The radioles can be folded and withdrawn into the tube.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 tne 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 isne the neuropodium. Chaetae in the two branches and along the body can vary greatly in their morphology, which can be critical in the taxon. Some tubes have transverse and 3 longitudinal ridges, and lack a peristome (flared opening). The branchial (gill) crown consists of about 14 radioles each on the left and right sides of the mouth. The peduncle is cylindrical. The opercular funnel has 31 radii with pointed tips. The verticil has 10 yellowish spines, all bending ventrally. The verticil lacks a central tooth. The collar chaetae:are bayonet chaetae, with two blunt-rounded to short teeth at their base, and a smooth distal blade. The thorax has six chaetigers bearing short, rasp-like setae, called uncinae, and limbate chaetae. The abdomen has about 89 segments (69-119, n=4). The overall length is about 16.5 mm (8-30, n=54. The worm is yellow to light brown. (Description from Bastida-Zavala and ten Hove 2002; Bastida-Zavala 2017).

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Taxonomy

Ecology

Food:

Phytoplankton, detritus

Trophic Status:

Suspension Feeder

SusFed

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Habitats

General Habitat	Coarse Woody Debris	None
General Habitat	Oyster Reef	None
General Habitat	Marinas & Docks	None
General Habitat	Rocky	None
General Habitat	Coral reef	None
General Habitat	Mangroves	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)	None	39
Broad Temperature Range	None	Subtropical-Tropical
Broad Salinity Range	None	Polyhaline-Euhaline

General Impacts

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References

Bastida-Zavala, J. Rolando; McCann, Linda D.; Keppel; Erica; Ruiz, Gregory M. (2017) The fouling serpulids (Polychaeta: Serpulidae) from United States coastal waters: an overview, European Journal of Taxonomy 344: 1-76

Bastida-Zavala, J. Rolando; Ten Hove, Harry A. (2002) Revision of Hydroides Gunnerus, 1768 (Polychaeta: Serpulidae) from the Western Atlantic region., Beaufortia 52(9): 103-178

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

Bastida-Zavala, Jose Rolando; Salazar-Vallejo, Sergio (2000) Serpulidos (Polychaeta: Serpulidae) del Caribe norocidental: Hydroides Y Serpula, Revista de Biologia Tropical 48(4): 841-858

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

Zibrowius, Helmut W. (1969) Hydroldes gairacensis Augener, 1934, a little known serpulid polychaete from Central and South America, Bulletin of Marine Science 19(2): 366-376

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