Invasion History

First Non-native North American Tidal Record: 1986
First Non-native West Coast Tidal Record:
First Non-native East/Gulf Coast Tidal Record: 1986

General Invasion History:

Mytella charruana is native to the tropical Western Atlantic from Colon, Panama (Ruiz et al., unpublished data) to Argentina (Lee 2001; Boudreaux and Walter 2006; Gillis et al. 2009). This mussel is also reportedly present in the tropical East Pacific, from Sonora, California to Ecuador, and the Galapagos Islands. However, Ecuadoran specimens were genetically distinct from Colombian (Caribbean Sea) or southeast US specimens, and showed no genetic overlap at the examined DNA sites (Gillis et al. 2009). Pacific M. charruana could represent a distinct cryptic species from the Atlantic form.

North American Invasion History:

Invasion History on the West Coast:

Invasion History on the East Coast:

In 1986, a heavy infestation of small mussels, later identified as Mytella charruana clogged the intakes of the Blount Island electrical generating plant in Jacksonville, Florida (FL). The mussels disappeared in the winter of 1987, but reappeared in the St. Johns estuary in 2006 (Lee 2008). In 2006 and 2007, they were found in small numbers, and in 2008, they again clogged the Blount Island Power plant (Lee 2008). It is not clear whether small, undetected populations persisted after the die-off, or whether the initial population was completely extirpated, and one or more subsequent invasions occurred. Genetic studies have found high genetic diversity, exceeding that in native Colombian populations (Gillis et al. 2009). In 2004, Mytella charruana was discovered in Mosquito Lagoon, FL part of the Indian River Lagoon system (Boudreau and Walters 2006). After 2006, they were found along the coast north to South Carolina, and appear to be established from central Florida to the central Georgia coast (Lee 2008; USGS Nonindigenous Species Program 2008; Gillis et al. 2009; Spinuzzi et al. 2012). Sporadic records have occurred north to Charleston, South Carolina (Pam Fuller, USGS, personal communication). However, severe winter weather in 2010 and 2011 has affected the abundance of other warm-water invaders in the region (Perna viridis, Green Mussel; Petrolisthes armatus, Green Porcelain Crab; Canning-Clode and Fowler, unpublished data), and has also reduced the range or abundance of M. charruana (Spinuzzi et al. 2012).

Invasion History on the Gulf Coast:

Invasion History in Hawaii:

Invasion History Elsewhere in the World:

In 2014, Mytella charruana was genetically identified in the port of Manila, Philippines, and found to be established in Manila Bay (Vallejo et al. 2017).


Description

Mytella strigata is small, thin-shelled, and lacks exterior ribs on its shell surface. On the interior of the shell the byssal retractor scar is nearly circular, and located further from the back than the more elongated, irregular scar in Mytilus edulis. The outside of the shell is light-green to black, and may be uniform or banded in a crisscross pattern. The internal surface of the shell is purple. The largest reported specimen of M. strigata is 48.7 mm, but a more typical size is 20-25 mm. (Description from: Lee 2001; Boudreaux and Walters 2006; Stenyakina et al. 2010)

Ecuadoran populations were genetically distinct, and did not overlap with Colombian (Caribbean) or introduced Florida and Georgia populations. Specimens of M. strigata were also genetically distinct from specimens of Mytella guyanensis from Brazil (Gillis et al. 2009).

This mussel was widely known under the name M. charruensis (d'Orbigny, 1846). Lim et al. (2018) and other recent authors (Sampanich and Wells 2019) and Tay et al. (2019) use the name Mytella strigata for this mussel, based on a detailed examination of 19th century publication dates (Lim et al. 2018). The World Registry of Marine Species now uses uses M. charruana (Appeltans et al. 2019).


Taxonomy

Taxonomic Tree

Kingdom:   Animalia
Phylum:   Mollusca
Class:   Bivalvia
Subclass:   Pteriomorphia
Order:   Mytiloida
Family:   Mytilidae
Genus:   Mytella
Species:   strigata

Synonyms

Mytilus strigatus (Hanley, 1843)
Mytilus charruanus (d'Orbigny, 1842)
Modiola strigata (Reeve, 1857)
Mytilus falcatus (d'Orbigny, 1846)
Mytilus sinuatus (Reeve, 1857)
Mytella charruana ((d'Orbigny), 1842)

Potentially Misidentified Species

Brachidontes exustus
None

Geukensia demissa
None

Mytella guyanensis
A closely related species, also known from the Caribbean-Brazil and tropical East Pacific (Mexico-Peru) (Gillis et al. 2009).

Mytilus edulis
None

Ecology

General:

Mytella strigata maintains separate sexes under conditions of steady food supply, but starvation results in a change of many individuals from female to male (Stenyakina et al. 2010). Eggs and sperm are released into the water. Development is planktotrophic with eggs developing into planktotrophic larvae and veligers, settling after about 14days at 29 C (Tan et al. 2018).

Mytella strigata is especially common in estuarine and lagoon environments. In Brazil, it is known from mangrove, mudflat, and rocky habitats (de Oliveira et al. 2005). In its introduced range, in the southeast US, it has been found on oyster beds, disarticulated shells, wood, roots, etc., but adult mussels were more common on artificial substrates, such as docks and power plants (Gilg et al. 2010; Lee 2001-2011). This mussel tolerates a wide range of salinities from 2 to 40 PSU (Yuan et al. 2010), but tolerance of low temperatures is limited. N the St. Johns River estuary, Florida, M. charruana was found at sites with average salinities ranging from 13 to 33 PSU, and highest densities at a mean salinity of 21 PSU). The upper temperature limit is at least 31?C, and likely to be higher (Brodsky et al. 2009- http://www.sicb.org/meetings/2009/schedule/abstractdetails.php3?id=413). I

Food:

Phytoplankton, detritus

Trophic Status:

Suspension Feeder

SusFed

Habitats

General HabitatCoarse Woody DebrisNone
General HabitatMangrovesNone
General HabitatMarinas & DocksNone
General HabitatRockyNone
General HabitatUnstructured BottomNone
Salinity RangeMesohaline5-18 PSU
Salinity RangePolyhaline18-30 PSU
Salinity RangeEuhaline30-40 PSU
Tidal RangeSubtidalNone
Tidal RangeLow IntertidalNone
Vertical HabitatEpibenthicNone

Life History


Tolerances and Life History Parameters

None4.9Maximum size at maturity (12.5 mm, Stenyakina et al. 2010)
Minimum Temperature (ºC)6Experimental data, stepwise transfers (Brodsky et al. 2009) http://www.sicb.org/meetings/2009/schedule/abstractdetails.php3?id=413
Maximum Temperature (ºC)31Experimental data, stepwise transfers (Brodsky et al. 2009) http://www.sicb.org/meetings/2009/schedule/abstractdetails.php3?id=413
Minimum Salinity (‰)2Experimental data, Yuan et al. 2010
Maximum Salinity (‰)40Experimental data, Yuan et al. 2010
Maximum Duration14Larval duration, 29 C (Tay et al. 2018)
Minimum Length (mm)4.9Stenyakina et al. 2010
Maximum Length (mm)12.5Minimum size at maturity (12.5 mm, Stenyakina et al. 2010)
Broad Temperature RangeNoneWarm temperate-Tropical
Broad Salinity RangeNoneMesohaline-Euhaline

General Impacts

In its introduced range in the southeastern US, Mytella charruana has shown a preference for settlement on natural substrates, such as disarticulated shells, wood, roots, etc., but survival was much greater on artificial substrates, such as docks and power plants (Gilg et al. 2010; Lee 2001-2011). Consequently, strong ecological impacts have not been reported in natural environments. This mussel is a local food resource in Brazil (de Oliveira et al. 2005), but is too small and rare to be utilized in the US.

In Thailand, extensive invasion by Mytilopsis sallei and Mytlella strigata (Charru Mussel) has coiverted soft-bottom lagoon communities to hard-bottom systems, resulting in the appearance and spread of some species requiring hard substrate, and the disappearance of others.  However, overall changes in species richness were not seen (Wangkulangkul et al. 2022).

Economic Impacts

Industry- Heavy settlements of M. charruana in 1986 clogged the intakes of the Blount Island electrical generating plant in Jacksonville, Florida. The mussels disappeared in the winter of 1987, but reappeared in the St. Johns estuary in 2006 (Lee 2008), and in 2008 they again clogged the Blount Island Power plant (Lee 2008).


Regional Impacts

S180St. Johns RiverEconomic ImpactIndustry
In 1986, a heavy infestation of Mytella strigata clogged the intakes of the Blount Island electrical generating plant. The mussels disappeared in the winter of 1987, and did not reappear in the St. Johns estuary until 2006 (Lee 2008). In 2006 and 2007, they were found in small numbers, but in 2008, they again clogged the Blount Island Power plant (Lee 2008).
CAR-VIICape Hatteras to Mid-East FloridaEconomic ImpactIndustry
In 1986, a heavy infestation of Mytella strigata clogged the intakes of the Blount Island electrical generating plant, in Jacksonville, Florida. The mussels disappeared in the winter of 1987, and did not reappear in the St. Johns estuary until 2006 (Lee 2008). In 2006 and 2007, they were found in small numbers, but in 2008, they again clogged the Blount Island Power plant (Lee 2008).
S190Indian RiverEcological ImpactCompetition
In experiments in Mosquito Lagoon, Florida, Mytella charruana, on fouling plates, did not affect the settlement of larvae of Eastern Oyster (Crassostrea virginica), but did reduce growth of oyster spat (Yuan et al. 2016). Feeding experiments show an overlap between M. charruana and the native oysters, and also a higher clearance rate for the mussels (Galimany et al. 2016).
CAR-INorthern Yucatan, Gulf of Mexico, Florida Straits, to Middle Eastern FloridaEcological ImpactCompetition
In experiments in Mosquito Lagoon, Florida, Mytella strigata, on fouling plates, did not affect the settlement of larvae of Eastern Oyster (Crassostrea virginica), but did reduce growth of oyster spat (Yuan et al. 2016). Feeding experiments show an overlap between M. strigataa and the native oysters, and also a higher clearance rate for the mussels (Galimany et al. 2016).
EAS-INoneEconomic ImpactFisheries
Negative impacts on commerical mussel culture of Perna perna, but a resource for local, informal shellfish gathering and aquaculturie (Fuertes et al. 2021).
EAS-INoneEcological ImpactHabitat Change

In Thailand, extensive invasion by Mytilopsis sallei and Mytlella strigata (Charru Mussel) has coiverted soft-bottom lagoon communities to hard-bottom systems, resulting in the appearance and spread of some species requiring hard substrate, and the disappearance of others.  However, overall changes in species richness were not seen (Wangkulangkul et al. 2022)

Regional Distribution Map

Bioregion Region Name Year Invasion Status Population Status
SA-IV None 0 Native Estab
SA-III None 0 Native Estab
SA-II None 0 Native Estab
CAR-III None 0 Native Estab
CAR-VI None 0 Native Estab
CAR-VII Cape Hatteras to Mid-East Florida 1986 Def Estab
CAR-I Northern Yucatan, Gulf of Mexico, Florida Straits, to Middle Eastern Florida 2004 Def Estab
S180 St. Johns River 1986 Def Estab
S190 Indian River 2004 Def Estab
S140 St. Catherines/Sapelo Sounds 2006 Def Estab
S090 Stono/North Edisto Rivers 2008 Def Unk
S183 _CDA_S183 (Daytona-St. Augustine) 2006 Def Estab
S170 St. Marys River/Cumberland Sound 2007 Def Estab
S110 Broad River 2009 Def Unk
SEP-I None 0 Crypto Estab
SEP-Z None 0 Crypto Estab
NEP-VII None 0 Crypto Estab
NEP-VIII None 0 Crypto Estab
NEP-IX None 0 Crypto Estab
SEP-H None 0 Crypto Estab
S160 St. Andrew/St. Simons Sounds 2007 Def Estab
S150 Altamaha River 2009 Def Estab
S120 Savannah River 2008 Def Estab
S080 Charleston Harbor 2016 Def Unk
S070 North/South Santee Rivers 2016 Def Unk
EAS-I None 2014 Def Estab
PAN_CAR Panama Caribbean Coast 0 Native Estab
EAS-VI None 2016 Def Estab
CIO-I None 2019 Def Estab
NWP-3a None 2019 Def Estab

Occurrence Map

OCC_ID Author Year Date Locality Status Latitude Longitude

References

2011-2015 World Registry of Marine Species. http://www.marinespecies.org/index.php

Boudreaux, Michelle L.; Stiner, Jennifer L.; Walters, Linda J. (2006) Biodiversity of sessile and motile macrofauna on intertidal oyster reefs in Mosquito Lagoon, Florida., Journal of Shellfish Research 25(3): 1079-1089

Boudreaux, Michelle L.; Walters, Linda (2006) Mytella charruana (Bivalvia: Mytilidae): a new invasive bivalve in Mosquito Lagoon, FL, Nautilus 120(1): 34-36

Calazans, Savio H.; Walters, Linda J.;; Fernandes, Flavio C. , Ferreira, Carlos E. L. ; Hoffman, Eric; A. (2017) Genetic structure provides insights into the geographic origins and temporal change in the invasive charru mussel (Sururu) in the southeastern United States, PLOS ONE 12(7): e0180619

de Oliveira, Miguel E.G.C.; Russo, Claudia A.M.; Lazoski, Cristiano Vianna, Paulo Roberto F.G.; Solé-Cava, Antonio M. (2005) Genetic variation and population structure of two species of neo-tropical mud-mussels (Mytella spp), Genetics and Molecular Research 4(2): 197-202

de Souza, Thainara Oliveira and 6 authors (2015) Population structure and identification of two matrilinear and one patrilinear mitochondrial lineages in the mussel Mytella charruana, Estuarine, Coastal and Shelf Science 156: 165-174

Gilg, Matthew R. and 5 authors (2010) Recruitment preferences of non-native mussels: Interaction between marine invasions and land-use changes, Journal of Molluscan Studies 76: 333-339

Gillis, Nancy K.; Walters, Linda J.; Fernandes, Flavio C.; Hoffman, Eric A. (2009) Higher genetic diversity in introduced than in native populations of the mussel Mytella charruana: evidence of population admixture at introduction sites, Diversity and Distributions 15: 784-795

2001-2015 Harry Lee's Florida Mollusca Checklists. http://www.jaxshells.org/florida.htm

Lodeiros, César; Hernández-Reyes, Dailos; Salazar, José Miguel; Rey-Méndez, Manuel; González-Henríquez, Nieves (2021) First report of the mussel Mytella strigata (Hanley, 1843) in the Venezuelan Caribbean from an invasion in a shrimp farm, Latin American Journal of Aquatic Research 49(3): 531-537

Madrid, Maycol; Collin, Rachel (2021) A checklist of the mollusks from the Miraflores and Pedro Miguel locks, Panama canal, panama, Technociencia 23(2): 125-150

Puyana, Mónica;; Prato, Julián; Día, Juan Manuel (2012) Mytella charruana (d’Orbigny) (Mollusca: Bivalvia: Mytilidae) en aa Bahía de Cartagena, Colombia, Boletín de Investigaciones Marinas y Costeras 41(1): 213-217

2007-2022 Indian River Species Inventory. http://www.sms.si.edu/irlspec/scylla_serrata.htm [Report by J. Masterson]

Spinuzzi, Samantha and 5 authors (2012) <missing title>, University of Central Florida, Orlando FL. Pp. unpaged

Stenyakina, A.; Walters, L. J.; Hoffmam, E. A.; Calestani, C. (2010) Food availability and sex reversal in Mytella charruana, an invasive bivalve in the southern United States., Molecular Reproduction and Development 77: 222-230

2003-2015 Nonindigenous Aquatic Species Database. Gainesville, FL. http://nas.er.usgs.gov

Wangkulangkul, Kringpaka; Hayeewachi, Lutfee; Rodcharoen, Eknarin (2022) Changes in benthic macro-invertebrate assemblages in an estuary in southern Thailand after invasion by non-native bivalves Mytilopsis sallei and Mytella strigata, Plankton & Benthos Research 17(2): 137–146

Yuan, W. Samantha; Hoffman, Eric A.; Walters, Linda J. (2016) <missing title>, 18 <missing publisher>, <missing place>. Pp. 689-701

Yuan, Wei; Walters, Linda J.; Schneider, Kimberly R.; Hoffman, Eric A. (2010) Exploring the survival threshold: a study of salinity tolerance of the nonnative mussel Mytella charruana, Journal of Shellfish Research 29(2): 415-422