Answer to Case 611

 Answer to Parasite Case of the Week 611: Female crab louse, Pthirus pubis, with an egg. She's a mom to be!

Florida Fan pointed out that we would be able to tell that this was a female louse, even if she wasn't gravid, due to the somewhat flattened, indented posterior (vs. the rounded posterior of the male).

Dr. Heaton was also kind enough to provide a beautiful egg (nit) from this case. It shows the classic features of a P. pubis nit, with a raised operculum:

This is in comparison to the flattened operculum of Pediculus humanus eggs:

Be sure to read the comments for some fun and helpful information, including an explanation from Kosta in why this louse's genus name is spelled Pthirus instead of Phthirus.