SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a59aa2eee0f3fdd7e0fdfbf601e7c2d4263c8b876ac03acf90266d7344bc6c9' 
  AND token = '+BKJRs2MKqKayjjWzGnFMMnAtw8h9+lGkQIuZix9S9U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}