SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '96d4d249a35fcf69a6a9620e73bfac6f1f6625ee99fb133e7ad9eef486cec857' 
  AND token = 'rRy5mzlNb3XdIJDLpt/QEbZODVj/3lMvNzdokbjW9A4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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