Paleontology can be divided into more than the study of fossils, for paleontology is much more. It's a rich field. It has been around for a long time and will be around even longer. Micropaleontology is the general study of microscopic fossils. No matter which group they belong to.
Paleobotany is where plant fossils are studied.
In addition to land plants, fossil algae and fungi are traditionally studied. Palynologists study pollen and spores from both living and fossilized specimens. These are usually produced by land plants and protists. Vertebrate paleontology studies vertabrate fossils. From primitive fish to mammals.