diff --git a/gallery_dl/extractor/gelbooru_v02.py b/gallery_dl/extractor/gelbooru_v02.py
index 0baad2fa..aad5752c 100644
--- a/gallery_dl/extractor/gelbooru_v02.py
+++ b/gallery_dl/extractor/gelbooru_v02.py
@@ -22,14 +22,14 @@ class GelbooruV02Extractor(booru.BooruExtractor):
     def _init(self):
         self.api_key = self.config("api-key")
         self.user_id = self.config("user-id")
-        self.api_root = self.config_instance("api_root") or self.root
+        self.root_api = self.config_instance("root-api") or self.root
 
         if self.category == "realbooru":
             self.items = self._items_realbooru
             self._tags = self._tags_realbooru
 
     def _api_request(self, params):
-        url = self.api_root + "/index.php?page=dapi&s=post&q=index"
+        url = self.root_api + "/index.php?page=dapi&s=post&q=index"
         return ElementTree.fromstring(self.request(url, params=params).text)
 
     def _pagination(self, params):
@@ -191,8 +191,8 @@ BASE_PATTERN = GelbooruV02Extractor.update({
     },
     "rule34": {
         "root": "https://rule34.xxx",
+        "root-api": "https://api.rule34.xxx",
         "pattern": r"(?:www\.)?rule34\.xxx",
-        "api_root": "https://api.rule34.xxx",
     },
     "safebooru": {
         "root": "https://safebooru.org",
diff --git a/gallery_dl/extractor/piczel.py b/gallery_dl/extractor/piczel.py
index 422325ff..fe267042 100644
--- a/gallery_dl/extractor/piczel.py
+++ b/gallery_dl/extractor/piczel.py
@@ -19,7 +19,7 @@ class PiczelExtractor(Extractor):
     filename_fmt = "{category}_{id}_{title}_{num:>02}.{extension}"
     archive_fmt = "{id}_{num}"
     root = "https://piczel.tv"
-    api_root = root
+    root_api = root
 
     def items(self):
         for post in self.posts():
@@ -75,7 +75,7 @@ class PiczelUserExtractor(PiczelExtractor):
         self.user = match.group(1)
 
     def posts(self):
-        url = "{}/api/users/{}/gallery".format(self.api_root, self.user)
+        url = "{}/api/users/{}/gallery".format(self.root_api, self.user)
         return self._pagination(url)
 
 
@@ -93,7 +93,7 @@ class PiczelFolderExtractor(PiczelExtractor):
         self.user, self.folder_id = match.groups()
 
     def posts(self):
-        url = "{}/api/users/{}/gallery".format(self.api_root, self.user)
+        url = "{}/api/users/{}/gallery".format(self.root_api, self.user)
         return self._pagination(url, int(self.folder_id))
 
 
@@ -108,5 +108,5 @@ class PiczelImageExtractor(PiczelExtractor):
         self.image_id = match.group(1)
 
     def posts(self):
-        url = "{}/api/gallery/{}".format(self.api_root, self.image_id)
+        url = "{}/api/gallery/{}".format(self.root_api, self.image_id)
         return (self.request(url).json(),)