Ficopomatus enigmaticus



Conservation status

Not Assessed

First reported in the wild



Invasive species - risk of Medium Impact

Irish status


Introduction pathways - 1

Transport Stowaway

Introduction pathways subclass - 1

Ship/boat hull fouling

Invasive score


NAPRA Ireland risk assessed


Species Biology


Serpulid polychaete that forms white calcareous tubes, 1.85-2mm in diameter and 20-40mm in length (Shumka et al., 2014). In Argentina it forms circular reefs up to 4m in diameter and up to 0.5 m in height (Obenat & Pezzani, 1994) but in South African colonies may form dense aggregations, on walls but typically are up to 50 cm across (Mead et al., 2011).


As a filter feeding reef building polychaete it has the potential to act as an ecosystem engineer but the exact mechanisms will depend on the form and level of invasion. For example, in the Zandvlei system on the Cape Peninsula, South Africa, F. enigmaticus is estimated to remove up to 130 kg of suspended material per hour, "effectively filtering the entire water volume every 26 hours" (Mead et al., 2011). Similarly in an Argentinean lagoon, F. enigmaticus removes material from the water column and deposits it as organic matter in the sediment, with a 45% decrease in phytoplankton biomass and a 50% decrease in turbidity (Bruschetti et al., 2011). Where the form dense reefs they provide a refuge for crab species lowering the density of the free-living soft-bottom polychaetes (Schwindt et al., 2001) and may facilitate the spread of digenean parasites (Etchegoin et al., 2012).




Annual iteroparous (multiple reproductive cycles), 1 to 2 batches of small eggs per female during each cycle producing planktotrophic larva which then settle as sedentary suspension-feeders (Obenat & Pezzani, 1994). Two periods of spawning and recruitment were observed at a lagoon in Argentina, in November-December and April-May, when water temperature is above 18°C (Obenat & Pezzani, 1994), though water temperature was not considered a cue for spawning, though oogenesis (egg production and growth) may be impeded below these temperatures (Obenat & Pezzani, 1994). As these temperatures are rarely realised in Ireland, similar to Britain one spawning would be more likely, which begins in June, with peak activity coinciding with the period of high water temperature in August and early September (Dixon, 1981).

Pathway and vector description

Probably introduced as a fouling organism on the hull of ferry's from the UK, possibly originating from Swansea (Kilty & Guiry,1973).

Mechanism of impact

Competition, Predation, Bio-fouling, Other

Broad environment


Habitat description

Generally found in lagoons and estuaries or areas with an influx of freshwater (Dixon, 1981; Obenat & Pezzani, 1994; Shumka et al., 2014).

Species group


Native region



World distribution(GBIF)

Irish distribution

Established - Locally abundant (Minchin, 2007a), found in Arklow and Dublin Bay (2007b), with one historic record from Cork Harbour (Kilty & Guiry, 1973).

Native distribution

Native to Australia but has widely colonised various parts of the world, including Britain, (Dixon, 1981), New Zealand (Read & Gordon, 1991), Argentina (Obenat & Pezzani, 1994), the Mediterranean (Shumka et al., 2014) and South Africa (Mead et al., 2011).

Temporal change

Date of first record category


Fifty year date category


Records submitted to Data Centre in 2019

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How can you help

Report any sightings to the National Biodiversity Data Centre.

Further information

Delivering Alien Invasive Species In Europe (DAISIE) project list this species as one of the 100 Worst Invaders in Europe.



Minchin, D. (2007a). A checklist of alien and cryptogenic aquatic species in Ireland. Aquatic Invasions, 2(4), 341-366. Minchin, D. (2007b). Rapid coastal survey for targeted alien species associated with floating pontoons in Ireland. Aquatic Invasions, 2(1), 63-70. Kilty, G. M., & Guiry, M. D. (1973). Mercierella enigmatica Fauvel (Polychaeta Serpulidae) from Cork Harbour. The Irish Naturalists' Journal, 379-381. Obenat, S. M., & Pezzani, S. E. (1994). Life cycle and population structure of the polychaete Ficopomatus enigmaticus (Serpulidae) in Mar Chiquita coastal lagoon, Argentina. Estuaries, 17(1), 263-270. Mead, A., Carlton, J. T., Griffiths, C. L., & Rius, M. (2011). Introduced and cryptogenic Marine and estuarine species of South Africa. Journal of Natural History, 45(39-40), 2463-2524. Schwindt, E., Bortolus, A., & Iribarne, O. O. (2001). Invasion of a reef-builder polychaete: direct and indirect impacts on the native benthic community structure. Biological Invasions, 3(2), 137-149. Etchegoin, J. A., Merlo, M. J., & Parietti, M. (2012). The role of the invasive polychaete Ficopomatus enigmaticus (Fauvel, 1923)(Serpulidae) as facilitator of parasite transmission in Mar Chiquita coastal lagoon (Buenos Aires, Argentina). Parasitology, 139(11), 1506-1512. Shumka, S., Kashta, L., & Cake, A. (2014). Occurrence of the nonindigenous tubeworm Ficopomatus enigmaticus (Fauvel, 1923)(Polychaeta: Serpulidae) on the Albanian coast of the Adriatic Sea. Turkish Journal of Zoology, 38(4), 519-521. Read, G. B., & Gordon, D. P. (1991). Adventive occurrence of the fouling serpulid Ficopomatus enigmaticus (Polychaeta) in New Zealand. New Zealand journal of Marine and Freshwater research, 25(3), 269-273. Dixon, D. R. (1981). Reproductive biology of the serpulid Ficopomatus (Mercierella) enigmaticus in the Thames Estuary, SE England. Journal of the Marine Biological Association of the United Kingdom, 61(03), 805-815. Bruschetti, M., Bazterrica, C., Fanjul, E., Luppi, T., & Iribarne, O. (2011). Effect of biodeposition of an invasive polychaete on organic matter content and productivity of the sediment in a coastal lagoon. Journal of Sea Research, 66(1), 20-28.

Global Invasive Species Database

DAISIE Factsheet

CABI Datasheet