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Wabash Pigtoe

Fusconaia flava

Summary 3

Fusconaia flava is a freshwater mussels in the family Unionidae. Wabash pigtoe is the common name used for Fusconaia flava.

Distribution 4

Global Range: (>2,500,000 square km (greater than 1,000,000 square miles)) This species is distributed along the entire Mississippi drainage from western New York to eastern Kansas, Nebraska, and South Dakota, south to Texas and Louisiana and Tombigbee River in Alabama (Parmalee and Bogan, 1998; Howells et al., 1996). In Canada, it occurs in the Lake Huron, Lek St. Clair, and Lake Erie drainage basins of Ontario, and in the Red River- Nelson River system of Manitoba (Clarke, 1981).

Habitat 5

The Wabash pigtoe is found from creeks to large rivers with moderate current in mud, sand or gravel. However, it is more common in streams than rivers. On the Huron River, it seemed to prefer a firm bottom of sand and fine gravel. In the Clinton it was found on a firm sand bottom.

Habitat Regions: freshwater

Aquatic Biomes: rivers and streams

Habitat 6

Habitat Type: Freshwater

Comments: This species may be found in medium sized rivers as well as big rivers at depts up to 15 feet. A stable substrate composed of coarse sand and gravel appears most suitable but it also tolerates other substrates (Parmalee and Bogan, 1998).

Iucn red list assessment 7


Red List Category
LC
Least Concern

Red List Criteria

Version
3.1

Year Assessed
2011

Assessor/s
Cummings, K. & Cordeiro, J.

Reviewer/s
Bhm, M. & Collen, B.

Contributor/s
Dyer, E., Soulsby, A.-M., Whitton, F., McGuinness, S., De Silva, R., Milligan, H.T., Kasthala, G., Thorley, J., Herdson, R., McMillan, K. & Collins, A.

Justification
Fusconaia flava has been assessed as Least Concern as it is widely distributed along the entire Mississippi drainage from western New York to eastern Kansas, Nebraska, and South Dakota, south to Texas and Louisiana and Tombigbee River in Alabama. In Canada, it occurs in the Lake Huron, Lake St. Clair, and Lake Erie drainage basins of Ontario, and in the Red River- Nelson River system of Manitoba. It is generally considered stable throughout most of its range and is not considered to be affected by any major threats at present.

Morphology 8

The Wabash pigtoe is up to 7.6 cm (3 inches) long , and is triangular to quadrate in shape. The shapes of headwater to river forms vary. Headwater forms are more rounded and river forms have a more prominent posterior ridge. The shell is fairly thick and compressed. The   anterior end is gently rounded, the posterior end bluntly pointed. The dorsal margin is short and straight. The ventral margin is rounded anteriorly and bluntly pointed posteriorly.

Umbos are broad and raised slightly above the hinge line. The beak sculpture has three to four weak concentric bars.

The periostracum (outer shell layer) is smooth, yellowish-brown to dark brown in older individuals. Faint green rays are visible in younger individuals.

On the inner shell, the   left valve has two   pseudocardinal teeth, which are heavy, rough, and serrated. The anterior tooth is narrow and elongate, the posterior one is heavy and triangular. The two lateral teeth are short and straight. The right valve has one large, serrated, pseudocardinal tooth, and one (sometimes two) are short, straight and stout.

The beak cavity is deep and wide. Although the nacre is white, occasionally it is has a pink or salmon tint and is iridescent posteriorly.

In Michigan, identification of F. flava can be easily confused with Pleurobema sintoxia, particularly in upper reaches of river systems. The sulcus of F. flava becomes more prominent in more downstream populations, making it more distinguishable from P. sintoxia. The Wabash pigtoe generally has a deeper beak cavity. When present in females, glochidial packets from the Wabash pigtoe also tend to be orangish while the round pigtoe has white glochidial packets.

Range length: 7.6 (high) cm.

Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry

Sexual Dimorphism: sexes alike

Nature serve conservation status 9

Rounded Global Status Rank: G5 - Secure

Reasons: This species is widely distributed along the entire Mississippi drainage from western New York to eastern Kansas, Nebraska, and South Dakota, south to Texas and Louisiana and Tombigbee River in Alabama. In Canada, it occurs in the Lake Huron, Lake St. Clair, and Lake Erie drainage basins of Ontario, and in the Red River- Nelson River system of Manitoba. It is generally considered stabel throughout most of its range.

Range description 10

This species is distributed along the entire Mississippi drainage from western New York to eastern Kansas, Nebraska, and South Dakota, south to Texas and Louisiana and Tombigbee River in Alabama (Parmalee and Bogan 1998, Howells et al.1996). In Canada, it occurs in the Lake Huron, Lake St. Clair, and Lake Erie drainage basins of Ontario, and in the Red River- Nelson River system of Manitoba (Clarke 1981).

Sources and Credits

  1. (c) Jason Whittle, some rights reserved (CC BY-NC-ND), uploaded by Jason Whittle
  2. (c) USFWSmidwest, some rights reserved (CC BY), http://www.flickr.com/photos/usfwsmidwest/6211980854/
  3. Adapted by rkkessler from a work by (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Fusconaia_flava
  4. (c) NatureServe, some rights reserved (CC BY-NC), http://eol.org/data_objects/28852472
  5. (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/31395256
  6. (c) NatureServe, some rights reserved (CC BY-NC), http://eol.org/data_objects/28852478
  7. (c) International Union for Conservation of Nature and Natural Resources, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/34467116
  8. (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/31395257
  9. (c) NatureServe, some rights reserved (CC BY-NC), http://eol.org/data_objects/28852466
  10. (c) International Union for Conservation of Nature and Natural Resources, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/34467117

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