Description
Mysidopsis almyra, described by Bowman in 1968 (Bowman 1968) was recognized as part of a distinctive northwest Atlantic group of 6 species within the genus Mysidopsis. Price et al. (1994) elevated this group to full genus status as 'Americamysis'. Potentially Misidentified Species- Americamysis bigelowi is the only congeneric mysid reported to occur in Chesapeake Bay (Van Engel and Sandifer 1972). However, A. bahia has been reported from Narragansett Bay, well north of its previously known range in the Gulf of Mexico (Price et al. 1994), and could occur in Chesapeake Bay. Americamysis bahia is much closer to A. almyra in the form of the telson than A. bigelowi (Stuck et al. 1979a).
Taxonomy
| Kingdom | Phylum | Class | Order | Family | Genus |
|---|---|---|---|---|---|
| Animalia | Crustacea | Malacostraca | Mysidacea | Mysidae | Americamysis |
Synonyms
Invasion History
Chesapeake Bay Status
| First Record | Population | Range | Introduction | Residency | Source Region | Native Region | Vectors |
|---|---|---|---|---|---|---|---|
| 1980 | Established | Unknown | Cryptogenic | Regular Resident | Western Atlantic | Western Atlantic | Shipping(Ballast Water) |
History of Spread
The mysid Americamysis almyra was described from specimens collected in Lake Ponchartrain, LA in 1953 (Bowman 1968). Subsequent collecting extended its range in the Gulf of Mexico south to Terminos Lagoon (Mexico) (Escobar-Briones and Soto 1988). Its first Atlantic collection was from the estuary of the St. Johns River FL in 1977 (Price and Vodopich 1979). In 1980, A. almyra was collected in July-September, in the Patapsco River MD, at an average density of ~1/m-3 (Grabe 1981). This is the only published Chesapeake record for this species. However, subsequent collecting has shown A. almyra to be abundant in Currituck Sound NC (Eaton 1994), and in other NC estuaries (Eaton 2000), and in GA and SC (Price 2000). Price considers the species, and its congener A. bahia, to be continously distributed along the Atlantic Coast to Chesapeake Bay and RI, respectively. He believes that it has been overlooked due to confusion with A. bigelowi. However, ballast water transport cannot be ruled out. Mysids of this genus were abundant in ballast water of ships, arriving from the Gulf of Mexico, and sampled in Baltimore (Ruiz et al., unpublished data).
Americamysis almyra has subsequently been recorded from the Patapsco River, but not from other Chesapeake Bay locations (Chesapeake Bay Program Database 2000). This species, and its congener A. bahia, may be common in the Bay, but overlooked due to confusion with A. bigelowi (Price 2000), which has been reported to occur throughout the Bay (Wass 1972).
History Reference - Bowman 1968; Eaton 1994; Escobar-Briones and Soto 1988; Grabe 1981; ; Price and Vodopich 1979; Price 2000
Invasion Comments
Ecology
Environmental Tolerances
| For Survival | For Reproduction | |||
|---|---|---|---|---|
| Minimum | Maximum | Minimum | Maximum | |
| Temperature (ºC) | 34.0 | 20.0 | 30.0 | |
| Salinity (‰) | 0.0 | 55.0 | 2.0 | 30.0 |
| Oxygen | ||||
| pH | 6.9000000000 | 9.0000000000 | ||
| Salinity Range | oligo-poly |
Age and Growth
| Male | Female | |
|---|---|---|
| Minimum Adult Size (mm) | 4.0 | 4.3 |
| Typical Adult Size (mm) | 4.9 | 5.3 |
| Maximum Adult Size (mm) | 5.5 | 9.4 |
| Maximum Longevity (yrs) | ||
| Typical Longevity (yrs | 0.2 | 0.2 |
Reproduction
| Start | Peak | End | |
|---|---|---|---|
| Reproductive Season | |||
| Typical Number of Young Per Reproductive Event |
|||
| Sexuality Mode(s) | |||
| Mode(s) of Asexual Reproduction |
|||
| Fertilization Type(s) | |||
| More than One Reproduction Event per Year |
|||
| Reproductive Startegy | |||
| Egg/Seed Form |
Impacts
Economic Impacts in Chesapeake Bay
Americamysis almyra has no known economic importance in the Chesapeake Bay region.
Economic Impacts Outside of Chesapeake Bay
Americamysis almyra has no direct economic importance in its native Gulf of Mexico, but it is important as a food for a wide range of juvenile and forage fishes (Ictalurus furcatus; Cynoscion arenarius; Micropogon undulatus; Sciaenops ocellatus; Menidia menidia; Bairdiella chrysura) (Bowman 1968).
References- Bowman 1968
Ecological Impacts on Chesapeake Native Species
Americamysis almyra has no known impacts on native Chesapeake biota. It could be a potential competitor with native mysids, especially A. bigelowi and Neomysis americana, but its interactions with these species have not been studied. In Gulf Coast estuaries, it is an important food organism for adult and juvenile fishes (Bowman 1968).
References- Bowman 1968
Ecological Impacts on Other Chesapeake Non-Native Species
Americamysis almyra has no known impacts on introduced Chesapeake biota. It could be a food source for juveniles of some introduced fishes (e.g. Ictalurus punctatus; I. furcatus; Lepomis spp.) (Bowman 1968).
References- Bowman 1968
References
Bowman, Thomas E. (1968) Mysidopsis almyra, a new estuarine mysid crustacean from Lousiana and Florida, Tulane Studies in Zoology 12: 15-18Eaton, Lawrence (1994) Preliminary survey of benthic macroinvertebrates of Currituck Sound, North Carolina, Journal of the Elisha Mitchell Scientific Society 110: 121-129
Escobar-Briones, Elva; Soto, Luis A. (1988) Mysidacea from Terminos lagoon, southern Gulf of Mexico, and description of a new species of Taphromysis, Journal of Crustacean Biology 8: 639-655
Grabe, Stephen A. (1981) Occurence of Mysidopsis almyra Bowman, 1964 (Mysidacea) in the Patapsco River estuary (Upper Chesapeake Bay), Maryland, U.S.A., Proceedings of the Biological Society of Washington 94: 863-865
Modlin, Richard F. (1982) Contributions to the ecology of the mysid crustaceans in the shallow waters of Dauphin Island, Alabama, Northeast Gulf Science 5: 45-49
Price, W. Wayne (1978) Occurrence of Mysdiopsis almyra Bowman, M. bahia Molenock andBowmaniella brasiliensis Bacescu (Crustacea, Mysidacea) from the eastern coast of Mexico., Gulf Research Reports 6: 173-175
2000 Status and distribution of <i>Americamysis</i> sp. on the Atlantic Coast, email.
Price, W. Wayne; Heard, Richard W.; Stuck, Lidia (1994) Observations on the genus Mysidopsis sars 1864, with the desgnation of a new genus, Americamysis, and the descriptions of Americamysis alleni and A. stucki (Peracarida: Mysidacea/Mysidae) from the Gulf of Mexico., Proceedings of the Biological Society of Washington 107: 680-698
Price, W. Wayne; Vodopich, Darrell S. (1979) Occurrence of Mysidopsis almyra (Mysidacea; Mysidae) on the east Coast of Florida, U. S. A., Crustaceana 36: 194-196
Reitsema, Lawrence A.; Neff, Jerry M. (1980) A recirculating system for the laboratory culture of Mysidopsis almyra (Crustacea; Pericaridea), Estuaries 3: 321-323
Stuck, Kenneth C.; Perry, Harriet M.; Heard, Richard W. (1979) Annotated key to the Mysidacea of the North Central Gulf of Mexico, Gulf Research Reports 6: 225-238
Stuck, Kenneth C.; Perry, Harriet M.; Heard, Richard W. (1979) Records and range extensions of Mysidaceae from coastal and shelf waters of the eastern Gulf of Mexico, Gulf Research Reports 6: 249-248
Wigley, Roland L.; Burns, Bruce R. (1971) Distribution and biology of mysids (Crustacea, Mysidacea) from the Atlantic coast of the United States in the NMFS Woods Hole collection, Fishery Bulletin 69: 717-746