A histological atlas for the Palinuridae (Crustacea: Decapoda: Achelata): A guide to parasite discovery and spotting the abnormal in spiny lobsters

Crustaceans suffer from diseases that can alter their survival and ecology with additional economic consequences
for fisheries and aquaculture. Many parasites have been described from crustaceans and with the advent of novel
technologies such as next generation sequencing, the discovery of novel parasites has become increasingly efficient.
Molecular techniques are beginning to surpass more conventional tools for parasite discovery, but they
typically do not provide information on pathology. Histopathology remains one of the least expensive methods
for parasite discovery and allows for both detection of parasites and descriptions of the pathology they cause.
When used in concert with modern molecular and electron microscopy techniques, the approach is powerful;
however, there are few informational tools for the interpretation of histological slides from crustaceans. Those
available do not provide comprehensive images of all organs and early works were limited to lower resolution
than currently available. More recent texts provide in-depth details of infection in histological section, but few
provide images of healthy material or describe a baseline from which to compare. Here, we provide a series of
image plates derived from histologically processed tissues from three palinurid lobsters: Panulirus argus,
Palinurus elephas and Panulirus guttatus. Histology from these lobsters shows high visual similarity in all tissue
types. We provide a histological atlas of healthy tissue that can be used as a baseline resource for pathobiologists
working on these common species (and related crustaceans) and we discuss how disease may result in visual
aberrations to these tissues.