Scientific name: Moxostoma congestum
Taxonomy
- Kingdom: Animalia
- Phylum: Chordata
- Class: Actinopterygii (ray‑finned fishes)
- Order: Cypriniformes
- Family: Catostomidae (suckers)
- Genus: Moxostoma
- Species: M. congestum
Common names
- Gray redhorse
- Gray shiner (regional usage)
Physical description
- Size: Adults typically reach 30–45 cm (12–18 in) in total length; maximum recorded lengths approach 60 cm (24 in).
- Weight: Up to approximately 1.5 kg (3.3 lb).
- Body shape: Elongated and laterally compressed, with a slightly arched back.
- Coloration: Dorsal surface gray to brownish‑gray; sides exhibit a subtle silver or pale hue; ventral surface lighter. A characteristic dark lateral stripe may be present, and fins are generally transparent to pale.
- Mouth: Subterminal, adapted for bottom feeding; lips are fleshy, and the mouth contains small, conical teeth.
- Scales: Cycloid scales covering the body; lateral line complete.
Distribution and habitat
- Geographic range: Native to the central United States, primarily within the Mississippi River basin, including the Missouri, Arkansas, and Ohio River drainages. Its range extends from southern Minnesota and Wisconsin southward to Texas and northern Louisiana.
- Habitat: Prefers medium‑ to large‑size rivers and streams with moderate to swift currents. Typically found over sand, gravel, or mixed substrate, often near riffles and runs. tolerates a range of water temperatures but prefers clear, well‑oxygenated waters.
Diet
- Primarily benthic macroinvertebrates, including insect larvae (e.g., mayflies, caddisflies), crustaceans, and small mollusks.
- Occasionally consumes detritus and filamentous algae, especially when invertebrate prey is scarce.
Reproductive biology
- Spawning season: Late winter to early spring (February–April), varying with latitude and water temperature.
- Reproductive strategy: Broadcast spawner; females release eggs over gravel substrates while males release sperm simultaneously. No parental care is provided.
- Fecundity: A mature female can produce several thousand to over ten thousand eggs, depending on size and condition.
Life history
- Age at maturity: Typically 3–5 years.
- Longevity: Recorded ages up to 12–15 years in the wild.
- Growth: Moderate, with rapid growth during the first three years, slowing thereafter.
Conservation status
- The International Union for Conservation of Nature (IUCN) has not assessed Moxostoma congestum separately; regional assessments generally categorize it as a species of “Least Concern” due to its relatively broad distribution and stable populations in many parts of its range.
- Threats: Habitat alteration (dam construction, channelization), water pollution, sedimentation, and competition with invasive species (e.g., Asian carp). Localized declines have been noted in heavily modified river systems.
Human interactions
- Fisheries: Not a primary target for commercial fisheries but is occasionally caught by anglers using baited hooks; valued as a sport or “catch‑and‑release” species in some regions.
- Ecological role: Functions as a benthic forager, helping to control invertebrate populations and contributing to nutrient cycling in riverine ecosystems.
References
- Page, L. M., & Burr, B. M. (2011). A Field Guide to Freshwater Fishes of North America. Houghton Mifflin Harcourt.
- NatureServe Explorer. (2023). Moxostoma congestum – Gray Redhorse. https://explorer.natureserve.org
- FishBase. (2023). Moxostoma congestum summary page. https://www.fishbase.de
This entry reflects the current consensus of peer‑reviewed scientific literature and reputable taxonomic databases.
