SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '08aa2d5b726761083fbddcd726ce20af132cce1317d91aa4e2b72b1a82e5c577' 
  AND token = 'xEh2MjrfUkwMnSAQe1cWcQdFZvYWIU9Ljo6JWNnaNco=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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