SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00a8dd14e9154df3d472aed484381ced167877f8b718e4cc89fb4adacfeae802' 
  AND token = 'FJh5bk/9XrbVVlMFHOFtB32J88wZrhjPSAFcfvY5lMk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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