SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1da0bbc3936fc51b8bf77395276e1f4bf4e10c04639917426a7288170f57a00' 
  AND token = '/gg8h/TNZLZhK6SWBlYfHzFZuuKhCkbDZXC8C9I1m0Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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