SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e41a9ae0367f76ea829d131b17fce9c462dc0dbc808ca6f56063e6c5384e7b37' 
  AND token = 'oUwgIX+hPIMUcOopHsAHfpnkKxqDTE6bFZsygZ5ez1w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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