In summer, tamarack looks like it would be one of the evergreens, because it bears needles. But this conifer is a deciduous tree. Likewise, not all evergreens are conifers. Holly shrubs are evergreen, but they are not conifers because they reproduce via flowers, not cones.
Fossil conifers included many diverse forms, the most dramatically distinct from modern conifers being some herbaceous conifers with no woody stems. Major fossil orders of conifers or conifer-like plants include the Cordaitales, Vojnovskyales, Voltziales and perhaps also the Czekanowskiales (possibly more closely related to the Ginkgophyta).
In conifer: Annotated classification †Class Cordaitopsida Paleozoic; strap-shaped leaves, up to 1 metre (3 feet) long, much larger than those of true conifers; both pollen and seed cones were compound and open, each bract with an axillary branch bearing numerous scale leaves surrounding pollen sacs or ovules; generally considered the…. Read More
The Pinophyta, also known as Coniferophyta or Coniferae, or commonly as conifers, are a division of vascular land plants containing a single extant class, Pinopsida. They are gymnosperms, cone-bearing seed plants. All extant conifers are perennial woody plants with secondary growth. The great majority are trees, though a few are shrubs.