Arthropods do use different opsins in their different eye types, but at least in Limulus the opsins expressed in lateral and in compound eyes are 99% identical and presumably diverged recently.
Limulus | Limulus amebocyte lysate | ''Limulus'' amebocyte lysate |
The organ's development through the lineage can be estimated by comparing groups that branched early, such as the velvet worm and horseshoe crab to the advanced eye condition found in insects and other derived arthropods.
Amebocytes from the blood of L. polyphemus are used to make Limulus amebocyte lysate, which is used for the detection of bacterial endotoxins in medical applications.
In molecular biology, the LCCL domain is a protein domain which has been named after several well-characterised proteins that were found to contain it, namely Limulus clotting factor C, Coch-5b2 (Cochlin) and Lgl1.