This fantastic photo is of one of the fragile little fungi that used to be all lumped together under Coprinus 'Ink Caps'. This Genus has been divided into Coprinus, Coprinopsis, Coprinellus and Parasola. Parasola tend to have a distinctive central 'eye' darker than the rest of the cap. These delicate fungi will appear overnight after rain and will usually completely disappear within 24 hours or less. They are black spored decomposers. Different species have different gill attachments so useful if a photo of gills.
Not to worry. In future, if you don't want to disturb the specimen, try experimenting with using a mirror to show the under surface. It takes a little practice but you can get some really good results.