SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa35127ee7045149200a43de8333e896ac512641e930fd413ced200b04ccf86d' 
  AND token = '1ErG+/5iIZX2ITWdLkMUrvJy1/9RvIKc5qulGlZdeLE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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