Family Osmeridae

1. Which fish species is described as having a large mouth, maxillary extending past the middle of the eye, a complete lateral line, striations on gill cover, rough-textured body, anadromous, found from Northern California to Alaska, heavily targeted by commercial fishery, and considered a tribal trust species?

Oncorhynchus mykiss (rainbow trout)

Salvelinus namaycush (lake trout)

Thaleichthys pacificus(eulachon or oil fish)

Oncorhynchus kisutch (coho salmon)

The correct answer is Thaleichthys pacificus, also known as eulachon or oil fish, which exhibits all the described characteristics. Lake trout, coho salmon, and rainbow trout do not match the given description.

Explanation

The correct answer is Thaleichthys pacificus, also known as eulachon or oil fish, which exhibits all the described characteristics. Lake trout, coho salmon, and rainbow trout do not match the given description.

2. Which fish species has the following characteristics: large mouth, maxillary extends past midpoint of eye, lateral line incomplete, large canine teeth on vomer, and is found in marine environments only?

Gadus macrocephalus (Pacific cod)

Allosmerus elongatus(whitebait smelt)

Thaleichthys pacificus (eulachon)

Engraulis mordax (northern anchovy)

Allosmerus elongatus fits the description provided, while the other options have distinct characteristics that do not match those listed in the question.

Explanation

Allosmerus elongatus fits the description provided, while the other options have distinct characteristics that do not match those listed in the question.

3. Which genus is characterized by having; a small mouth, maxillary that does not extend past midpoint of the eye, lateral line incomplete?

Genus Salmo

Genus Hypomesus

Genus Scomber

Genus Acipenser

The correct answer is Genus Hypomesus because it is the only genus among the options that fits the given characteristics of having a small mouth, maxillary that does not extend past midpoint of the eye, and an incomplete lateral line.

Explanation

The correct answer is Genus Hypomesus because it is the only genus among the options that fits the given characteristics of having a small mouth, maxillary that does not extend past midpoint of the eye, and an incomplete lateral line.

4. What species has a head length LESS than 4X the diameter of eye, and LESS than 2.5X the longest anal fin ray, with scales in lateral series 53-60, and can be found in Exotic - Japan, Freshwater lagoons, with Anadromous and Freshwater forms?

Salvelinus fontinalis (Brook trout)

Hypomesus nipponensis(wakasagi)

Oncorhynchus mykiss (Rainbow trout)

Oncorhynchus keta (Chum salmon)

The correct answer, Hypomesus nipponensis (wakasagi), fits all the criteria mentioned in the question. The incorrect answers are commonly found in different habitats and do not match the specific characteristics described in the question.

Explanation

The correct answer, Hypomesus nipponensis (wakasagi), fits all the criteria mentioned in the question. The incorrect answers are commonly found in different habitats and do not match the specific characteristics described in the question.

5. Which fish has a head more than 4 times the diameter of the eye, and more than 2.5 times the longest anal fin ray, scales in lateral series 66-73, and is found in marine and brackish environments?

Salmo salar (Atlantic salmon)

Alosa sapidissima (American shad)

Hypomesus pretiosus(Surf smelt or Day smelt)

Osmerus mordax (Rainbow smelt)

Hypomesus pretiosus meets all the criteria mentioned in the question, including head size, anal fin ray length, scale count, and habitat. The incorrect answers do not meet the specific criteria outlined for the fish described in the question.

Explanation

Hypomesus pretiosus meets all the criteria mentioned in the question, including head size, anal fin ray length, scale count, and habitat. The incorrect answers do not meet the specific criteria outlined for the fish described in the question.

6. Which Genus is characterized by having a large mouth, maxillary that extends past middle of the eye, lateral line absent or obsolete, and no striations on gill cover?

Genus Gadus

Genus Oncorhynchus

Genus Spirinchus

Genus Salvelinus

Genus Spirinchus fits the description provided with its distinct characteristics. Genus Gadus, Genus Oncorhynchus, and Genus Salvelinus do not match all the given criteria.

Explanation

Genus Spirinchus fits the description provided with its distinct characteristics. Genus Gadus, Genus Oncorhynchus, and Genus Salvelinus do not match all the given criteria.

7. What fish species has an angle of jaw measuring 54-65 degrees to the top of the snout, mid-lateral scales numbering between 60-66, and no striations on the operculum?

Spirinchus starksi(night smelt)

Trachidermus fasciatus (rockweed gunnel)

Atherinops affinis (topsmelt)

Clinocottus analis (tidewater goby)

The correct answer is Spirinchus starksi (night smelt) as it matches the given description with the angle of jaw, mid-lateral scales, and absence of striations on the operculum. The incorrect answers are different fish species that do not align with all the characteristics mentioned in the question.

Explanation

The correct answer is Spirinchus starksi (night smelt) as it matches the given description with the angle of jaw, mid-lateral scales, and absence of striations on the operculum. The incorrect answers are different fish species that do not align with all the characteristics mentioned in the question.

8. Which fish species has an angle of jaw of 68-90 degrees to the top of the snout, mid-lateral scales numbering 54-65, no striations on operculum, a long pectoral fin nearly reaching the base of the anal fin, a huge anal fin ray, and is native to Humboldt Bay?

Salmo salar (Atlantic salmon)

Spirinchus thaleichthys(longfin smelt)

Clupea harengus (Atlantic herring)

Oncorhynchus mykiss (Rainbow trout)

The characteristics described in the question match those of Spirinchus thaleichthys, commonly known as the longfin smelt. This fish species is characterized by its specific physical features and habitat, making it the correct answer to the question.

Explanation

The characteristics described in the question match those of Spirinchus thaleichthys, commonly known as the longfin smelt. This fish species is characterized by its specific physical features and habitat, making it the correct answer to the question.