Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ff51db5e953d9e80012a9c6699067cd665ce585379574286eccab64066abc0af' 
  AND token = 'tHUdbbTsJ4B+SmQa3CsTdsJLY+ZrTlB8+MKQnZU4eRU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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