Another possible development in the Nancy Guthrie abduction case today ... investigators have found a black glove in the area where she was last seen that could bring them one step closer to nabbing the masked suspect who allegedly took her.

An FBI agent plucked the glove from the side of a road about 1.5 miles from Nancy's Tucson-area house ... The Post was the first to report the discovery.

Yesterday, the FBI released images and video of the alleged kidnapper, wearing a ski mask, a backpack, and gloves ... which appeared to be black. The person also had what looked like a holstered gun on the front of their waist.

As you know ... authorities have not identified any suspects in the ongoing search for Savannah Guthrie's mother, who was reported missing on February 1 ... the culprit is believed to be from the Tucson area.

When examined closely, the images appear to reveal that the individual has prominent facial hair.

Anyone with information is asked to contact 1-800-CALL-FBI or visit tips.fbi.gov ... a $50,000 reward is being offered "for information leading to the recovery of Nancy Guthrie and/or the arrest and conviction of anyone involved in her disappearance."