The most common and most likely answer to this crossword clue is the 6 letter word SEPIAS
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More clues leading to the result SEPIAS
Buddy explains!

The straight part
We know that "Some cuttlefishes" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case some cuttlefishes = sepias.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SEPIAS mean?
SEPIAS noun- A dark brown pigment made from the secretions of the cuttlefish.
- A dark, slightly reddish, brown colour.
- (by extension) A sepia-coloured drawing or photograph.
- The cuttlefish.