Sense Sonnet - Pumper

Horseshoe Crab

The horseshoe crab, researchers say,
Is really not a crab at all.
Horseshoe shaped shell it does display,
But an arachnid is the call,
Related to spiders on land,
Genomic sequencing does tell.
As some researchers understand,
A water spider in a shell.
The research shows that long ago
Some arachnids crawled from the sea,
Becoming spiders that we know.
The horseshoe crab stayed where it be.

The horse shoe arachnid - a new name?
Maybe a change, maybe the same.