I urge everyone to bookmark that blog; it is always a fascinating tour of the weirder and wonderfuller places on our planet. And let me leave you with this simply jaw-dropping video of undulatus asperatus in action.
(A sunscreen with a physical block like titanium dioxide or zinc oxide can be applied last, after a serum or moisturizer.) Apply a serum next and, finally, moisturizer if you need it. Polis also recommends serums or sunscreens with moisturizers built in because they save time.
For tests requiring serum, a blood sample is drawn into a tube containing no anticoagulant. The blood must be allowed to clot for approximately 30 minutes before centrifugation. Clotted blood should then be centrifuged for 10-15 minutes. The serum can then be separated from the cells and transported in an aliquot tube, if necessary. The use of a transfer pipette is the required method, please DO NOT tilt the original tube when separating the serum into an aliquot tube.