Ancient filet crochet books are often a source of inspiration for potential knits.
Archive.org offers one search method for historical results.
The site is free to use; small donations are optional.
I have seen many references from this site and from https://mkmanuals.com/ downloaded and being sold online.
I live on the East Coast of the US, where crustaceans of all types are easily available in seafood sections of markets and restaurants.
This plate from a 1912 pub 
initially caught my eye.
The first repeat tested was knit in DBJ with birdseye backing,
I was not happy with the swatch, measuring 8.75 X 8 inches, and got distracted, as often happens, by other rabbit holes.
The present 76X76 PNG 
was used to test knit in DBJ with striper backing; the result was definitely more square, measuring 11X11 inches.
Although the two swatches share the same color way, they are knit using different yarns.
Plied yarns were problematic with feeding evenly and getting hung up on gate pegs, a first in my many years of knitting DBJ. 
After several stubborn starts and switching to a different single ply shade of white, knitting went smoothly.
Each lobster occupies less than a quarter of the full repeat, 19 stitches, illustrating some of the limitations in detail when reducing identifiable images to 8-bit small designs. 
Not to be left out, the crab in the lower border, on the same page, 30X25
Inspired by the above and other filet crochet references:
an army of frogs that began with a border chart; 
the 27X83 PNG
in half drop, 81X83
a punchcard version, 24X56
Other design repeats from the same and similar other sources to play with in electronic DIY:
ladybug, 27X27
bunnies:
30X29
103X37
squirrels
41X1
roosters
39X39
39X41
59X59
fictional
30X29
31X31
50X51
61X52
75X76
Bordered, larger-scale tiles
57X57
87X85
87X87
87X87
87X87
92X91
93X93
95X95
previously shared 165X230 
to trim, edit, and make your own, 202X134.
A touch of mythology, 152X81.
For an updated list of links to previous posts, please see the blog index, new listing DESIGN REPEAT COLLECTIONS