Fish of the Day

Today's fish of the day is the Olympic mudminnow! 

The Olympic mudminnow, also known by scientific name Novumbra hubbsi, is the last remaining fish of the Novumbra genus. The name comes from Latin, with the genus Novumbra being split into Novus, meaning new, and Umbra, meaning shadow. The species name hubbsi, is named after Carl Levitt Hubbs, a great American Ichthyologist. Despite their common name being mudminnow, these fish are within the pike family, and are not actually minnows. Found only in Washington state, in Southern coastal drainage and lowlands across the Olympic valley and peninsula. Living in areas of low oxygen, slow water, and muddy bottoms; such as streams, ditches, and wetlands. Reside anywhere from 4-35 °C, so long as there is dense vegetation or other aquatic debris. 

The Olympic mudminnow is carnivorous, eating both benthic and aquatic invertebrates. Primarily the diet is made of various crustaceans and insect larvae, although adults also eat full grown insects.  This allows them to reach a maximum size of 8cm, although the most common size in adults is 5.5cm, just between 2-3 inches. Not only the smallest mudminnow, but also the smallest fish in the pike family. This sizing makes them vulnerable to predators,such as largemouth bass. Although it is rare, these fish can hide in sediments, covering themselves in a fine layer to hide from predators. The introduction of many invasive stocked fish, for sport fishing, as well as wetland areas being built on has made the species vulnerable, despite healthy populations, they are significantly reduced from what once was. 

Like all mudminnows, the Olympic mudminnow will breed in the early months of the year, after overwintering. Unlike other mudminnows, the Olympic will begin breeding season in November, and continue it until June. Male and female fish change from the normal olive green colors to a dark iridescent coloration, with females growing noticeably fatter with eggs. Male fish grow incredibly territorial, choosing and protecting a small area, even chasing off the female they spawn with after eggs are fertilized. Spawning must occur multiple times, as these fish will release only 1-2 eggs at a time, carrying very few eggs per season. The fertilized eggs settle into vegetation, and hatch after 10 days, however the fry will remain attached to vegetation until the egg sac is fully absorbed in another week. After this, the juvenile fish are free swimming, and receive no prenatal care. We know little about the Olympic mudminnow lifecycle, although based on the information of other mudminnows, they likely sexually mature after 1-2 years, after which it is unknown how long the fish live. 

(breeding season male and female fish)

That's the olympic mudminnow fish, and have a wonderful day! 

Round 3 - Actinopterygii - Esociformes

(Sources - 1, 2, 3, 4)

Order: Esociformes (or Suborder Esocoidei)

Common Name: “pikes” and “mudminnows”

Families: 2 - Esocidae (“pikes”, “pickerel”, and “mudminnows”) and Umbridae (“Umbra mudminnows”)

Anatomy: broad and flat head; long and slender body; relatively large posterior dorsal fin and anal fins; large, lobed pectoral fins; large caudal fin

Diet: sight-based ambush predators, taking any animal they can fit in their mouth

Habitat: weedy freshwater habitats in North America and northern Eurasia

Evolved in: Late Cretaceous

Originally posted by bethanythebogwitch

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Taxonomy Tournament: Fish

Esociformes. This order is made up of pike and mudminnows, freshwater ambush predators.

Galaxiiformes. This order is made up of mostly small freshwater fish in the Southern Hemisphere, including galaxias and mudfish.