There are THREE main catagories according to reptoid.com
Draco have wings. These wings are made of long, thin bony spines or ribs that protrude out of their backs. The ribs are adjoined by flaps of leathery, blackish-brown skin. The wings are usually in a retracted position. In some instances, such as reported by author John Keel (‘MothMan Prophecies), the beings matching descriptions of the Draco have been seen to actually fly by use of their wings. (With the beings neck cranked downwards upon spectators, the glowing red reflective eyes of a flying Draco would appear to be placed in the middle of their chest as described by eyewitnesses.)
They have scaled skin that is usually greenish-brown in color. Some also have coffee colored scales that have dark green colored rims. The scales (or scutes) on their backs, thighs and upper arms are usually large. Their hands, abdomen and face are covered with smaller scales, allowing more flexibility. They have wide lipless mouths and the majority of them are reported to have differentiated types of dentition (teeth,) including canines (fangs.)
In addition to the Draco and Reptoids, the various crossbreed types that many people claim to have encountered share the following physical characteristics.
Most of the reptilian-grey crossbreeds are rather diminutive in size. They are four to four and a half feet in height. They have oversized craniums, large black eyes with vertical slit pupils, no ears, slight torsos, arms and legs.
There have been reports of these creatures as having either three fingers with a fourth opposable or only three long fingers and no opposable fourth. They have been seen to have short claws and in some cases, no claws at all. Their feet are usually covered by the material of their suite, but some experiencers have described their feet as short and stubby, with no toes.
Amidst the various reptilian-grey types, there is also a species that has greenish-tan skin, large almond-shaped eyes that are golden in color with a dark, metallic green vertical slit pupil. They share the same basic physical construct as a grey entity and are usually seen wearing a one piece suite that is the same color as their skin.
Reptoids range from five and a half to 9 feet in height. They have lean, firm bodies with powerful arms and legs. They have long arms with three long fingers and an opposable thumb. Their feet have three toes and one recessed fourth that is toward the back side of their ankle. The claws are short and blunt. They do not have teats on their upper torso nor do they have a navel.
Reptoids have either large black eyes with vertical slit pupils or eyes that are white with flame colored vertical slit pupils. Their heads are slightly conical in shape and have two bony ridges riding from their brow, across their back sloping skull, toward the back of their head.