A Mastic Beach teenager arrested for allegedly sexually abusing his family’s dog was also accused of downloading child pornography, according to the Suffolk County Society for the Prevention of Cruelty to Animals. Zachary Carlisle, 19, pleaded not guilty on July 30 at Suffolk County court to a misdemeanor charge of sexual misconduct and 25 counts of possessing a sexual performance by a child. “It was an extremely disturbing case of animal cruelty and sexual misconduct,” Roy Gross, chief of the Suffolk County SCPA, told reporters at the agency’s Smithtown headquarters. The initial video only identified the suspect as Zachary from Mastic Beach, New York. “The Suffolk County Police Department had one of their analysts do a facial recognition social media search.”