SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e07f527fa59fda2e614f052ce35038302bff21a8963a4c3bea138b843823114c' 
  AND token = 'ig8qv7tXWv0BkIIjMHK/Wob7k0EZdhCkfDPbMIoxfk0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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