SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7225b4b8d4fd671400352fb94f974aa345a96aa290da561da7eba8df5c31cbe5' 
  AND token = 'Z4hVGsBhXl6rGmzQeJgBvncIH9zIUUpEyrsHludGIDA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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