0304.42.00.00 - Trout (Salmo trutta, Oncorhynchus mykiss, Oncorhynchus clarki, Oncorhynchus aguabonita, Oncorhynchus gilae Oncorhynchus apache, and Oncorhynchus chrysogaster)

This HTS category, 0304.42.00.00, specifically covers fresh or chilled fillets of trout. This includes a variety of trout species such as *Salmo trutta*, *Oncorhynchus mykiss* (Rainbow Trout), *Oncorhynchus clarki* (Cutthroat Trout), *Oncorhynchus aguabonita* (Golden Trout), *Oncorhynchus gilae*, *Oncorhynchus apache*, and *Oncorhynchus chrysogaster*. The key characteristic for this classification is that the fish are presented in fillet form and are either fresh or have been chilled.

Distinguishing this category from its siblings is crucial for accurate classification. For instance, sibling 0304.41.00 classifies fillets of Pacific and Atlantic salmon, as well as Danube salmon, which are distinct species from the trout covered here. Similarly, 0304.43.00 covers flatfish, and 0304.44.00 covers fish from specific families like Gadidae (cod), all of which are morphologically and taxonomically different from trout. This category is specifically for trout species, differentiating it from broader or other fish fillet classifications.

As this HTS code represents a leaf node, there are no further subcategories within 0304.42.00.00. Therefore, the focus remains on the precise identification of trout fillets in a fresh or chilled state. Classification into this specific code relies on the accurate identification of the species of trout and confirmation that the product is in fillet form and has not been frozen, distinguishing it from frozen fillets of the same species which would be classified elsewhere.