Branchiura sowerbyi
Common Name:
A tubificid worm
Synonyms and Other Names:
Identification:
Branchiura sowerbyi is easily differentiated from other tubificids by the presence of gills (Gustafson 1996). It has a dorsal and a ventral gill pair on each segment in the posterior 25% of the body (Barnes 1980). The worm lives with its head buried in the mud and its tail waving actively in the water above. Branchiura sowerbyi is a large, deep red worm, usually 10–15 cm long as an adult (Wang and Matisoff 1997). Dorsal and ventral setae are different with ventral setae bifurcate and the dorsal setae bifurcate or mixture of two or three types. The anterior dorsal bundles contain 6–9 short setae, and 1–3 capillary setae. The ventral bundles contain 7–11 setae. The tips of the anterior ventral bundles are single and they gradually change into bifid setae behind the fifth segment. The clitellym occupies segments 10, 11, 12. Coelomocytes are sparse or absent (Goodnight 1959, Pennak 1978). Branchiura is prone to fragmenting and anterior fragments may be mistaken for Aulodrilus pluriseta (Gustafson 1996).
Size:
20 to 185 mm long
Native Range:
Branchiura sowerbyi is generally thought to be a native of tropical and subtropical Asia (Mills et al. 1993), but some think it is just most conspicuous in these places and is naturally widespread (Gustafson 1996).
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This map only depicts Great Lakes introductions.
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Great Lakes Nonindigenous Occurrences:
This species occurs in California starting in the 1950s. It was first reported in Ohio in 1930. In the Great Lakes system, 1st reported in the Lake Michigan drainage in 1951. Branchiura sowerbyi has also been reported in Lakes Erie, St. Clair, and Huron and the St. Clair and Detroit Rivers (Mills et al. 1993, Spencer and Hudson 2003).
Table 1. Great Lakes region nonindigenous occurrences, the earliest and latest observations in each state/province, and the tally and names of HUCs with observations†. Names and dates are hyperlinked to their relevant specimen records. The list of references for all nonindigenous occurrences of Branchiura sowerbyi are found here.
Table last updated 11/21/2024
† Populations may not be currently present.
Ecology:
Branchiura sowerbyi is a freshwater benthic deposit feeder that prefers rivers and warmer waters.
Means of Introduction:
Branchiura sowerbyi was probably introduced to the United States, as well as globally, with the importation of aquarium specimens. It was first discovered in Ohio in 1930 and since then has been widely distributed throughout North America (Mills et al. 1993). Speculation has been that Branchiura sowerbyi was introduced in the Great Lakes by an accidental release from imported aquatic plants in 1951, and subsequently it has appeared in Lake St. Clair and western Lake Erie (Mills et al.1993, Spencer and Hudson 2003). Alternatively, B. sowerbyi may have been naturally widespread, only more conspicuous in warmer waters (Gustafson 1996).
Status:
Established sporadically and widely around the U.S.
Great Lakes Impacts:
Summary of species impacts derived from literature review. Click on an icon to find out more...
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GLANSIS is currently adding new, standardized Great Lakes-specific impact assessments to species fact sheets. During this period, there may be some redundancy with the "Impact of Introduction" section above. Once all species' Great Lakes impacts have been entered here, this information will replace the original Impact section, which will then appear only on the USGS NAS site. Current research on the environmental impact of Branchiura sowerbyi in the Great Lakes is inadequate to support proper assessment.
Realized:
Branchiura sowerbyi is a conveyor-belt feeder that mixes benthic sediments, bringing deeper sediments to the surface (Matisoff et al. 1999). Branchiura sowerbyi can transport large quantities of sediment particles from deep zones and may enhance solute transport between sediments and overlying water. Due to its larger size, B. sowerbyi can homogenize layers to a greater depth than some other oligochaetes that are abundant in parts of the Great Lakes, including Limnodrilus hoffmeisteri and Tubifex tubifex (Matisoff et al. 1999).
Potential:
Potentially, it can have a large impact on its surroundings as it can make burrows to a depth of 20 cm and after a short period of time move to a new location to build new burrows (Wang and Matisoff 1997).
Branchiura sowerbyi, with other oligochaetes, has been documented as a host of myxosporean parasites which cause fish pathogens such as swim-bladder disease and haemorrhagic thelohanellosis in Asia and Europe, and its presence has been correlated to high levels of infection in fish (Liyanage et al. 2003).
There is little or no evidence to support that Branchiura sowerbyi has significant socio-economic impacts in the Great Lakes.
Current research on the beneficial effect of Branchiura sowerbyi in the Great Lakes is inadequate to support proper assessment.
Potential:
Branchiura sowerbyi has been used in the past as a research organism to determine toxic levels of various chemicals (e.g., Das and Das 2005, Ghosh and Konar 1983, Saha et al. 2006).
Management:
Regulations
There are no known regulations for this species.
Note: Check federal, state/provincial, and local regulations for the most up-to-date information.
Control
Branchiura sowerbyi has not received much attention regarding control studies. The effects of industrial toxicants on Tubificidae species and explorations of their value as an indicator of environmental quality have been explored, but chemicals and heavy metals are not viable methods of control because of unknown and adverse effects on the surrounding environment (Das and Das 2005, Saha et al. 2006). However, there has been investigation into the control of Branchiura sowerbyi as a host of haemorrhagic thelohanellosis, which negatively impacts fish in aquaculture (Liyanage et al. 2003).
Biological
Brown trout, Salmo trutta L., has been shown to prey on oligochaetes; its removal from an experimental environment led to rapid multiplication of benthic fauna (Wahab et al. 1989). However, brown trout is itself an invasive species in the Great Lakes region and across nearly all of the United States (Fuller et al. 2013).
Physical
Researchers found that Branchiura sowerbyi, which is a vector in transmission of Thelohanellus hovorkai (myxozoa) to fish, prefers muddy substrate, while other benthic oligochaetes that are not susceptible to myxozoa prefer sandy substrate, and suggested that replacing bottom substrate from mud to sand would lead to a shift in oligochaete communities from Branchiura sowerbyi to non-susceptible oligochaetes such as Limnodrilus socialus, therefore reducing disease in aquaculture fauna (Liyanage et al. 2003).
Chemical
While there are no known chemical controls specifically for Branchiura sowerbyi, declines in Oligochaeta in southern Lake Michigan were recorded between 1980 and 1993 in correlation with reductions in phosphorus loads (Nalepa et al. 1998), suggesting that reduction of excess nutrients would help to reduce oligochaete populations.
Note: Check state/provincial and local regulations for the most up-to-date information regarding permits for control methods. Follow all label instructions.
References
(click for full reference list)
Author:
Liebig, J., J. Larson, and A. Fusaro
Contributing Agencies:
Revision Date:
9/12/2019
Citation for this information:
Liebig, J., J. Larson, and A. Fusaro, 2024, Branchiura sowerbyi: U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, and NOAA Great Lakes Aquatic Nonindigenous Species Information System, Ann Arbor, MI, https://nas.er.usgs.gov/queries/greatlakes/FactSheet.aspx?Species_ID=1151, Revision Date: 9/12/2019, Access Date: 11/21/2024
This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.