SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c44fc4885b76539eff12396b23437f51eefb4426380d66e59ce819fb229210fb' 
  AND token = 'dMt1VqNxoFiBBDIak1jQO4u9wmhkcN/WLJbqG7Jc5/w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}