diff --git a/skimage/io/_io.py b/skimage/io/_io.py
index ce718742..1a938408 100644
--- a/skimage/io/_io.py
+++ b/skimage/io/_io.py
@@ -1,3 +1,4 @@
+import os
 from io import BytesIO
 
 import numpy as np
@@ -5,7 +6,6 @@ import six
 
 from skimage.io._plugins import call_plugin
 from skimage.color import rgb2grey
-from skimage._shared import six
 from .util import file_or_url_context
 
 
@@ -95,7 +95,14 @@ def imread(fname, as_grey=False, plugin=None, flatten=None,
         as_grey = flatten
 
     with file_or_url_context(fname) as fname:
-        img = call_plugin('imread', fname, plugin=plugin, **plugin_args)
+        function = 'imread'
+        # TODO: This should probably use imghdr to get the image format.
+        try:
+            _, extension = os.path.splitext(fname)
+            function = function + extension
+        except AttributeError:  # Buffers don't work with splitext
+            pass
+        img = call_plugin(function, fname, plugin=plugin, **plugin_args)
 
     if as_grey and getattr(img, 'ndim', 0) >= 3:
         img = rgb2grey(img)
diff --git a/skimage/io/inherited_config.py b/skimage/io/inherited_config.py
index 446e6db7..9cbc7857 100644
--- a/skimage/io/inherited_config.py
+++ b/skimage/io/inherited_config.py
@@ -32,7 +32,10 @@ class InheritedConfig(dict):
 
         super(InheritedConfig, self).__init__(config_values, **kwargs)
 
-    def get(self, key, default=None, _prev=None):
+    def __getitem__(self, key):
+        return self.get(key, _raise=True)
+
+    def get(self, key, default=None, _raise=False):
         """Return best matching config value for `key`.
 
         Get value from configuration. The search for `key` is in the following
@@ -94,11 +97,13 @@ class InheritedConfig(dict):
         1
         """
         if key in self.keys():
-            return self[key]
+            return super(InheritedConfig, self).__getitem__(key)
         elif default is not None:
             return default
         elif self._separator in key:
             return self.get(self._parent(key))
+        elif _raise:
+            raise KeyError('%r not in %s' % (key, self.__class__.__name__))
         else:
             return None
 
diff --git a/skimage/io/tests/test_inherited_config.py b/skimage/io/tests/test_inherited_config.py
index 5521da0b..207d3cf1 100644
--- a/skimage/io/tests/test_inherited_config.py
+++ b/skimage/io/tests/test_inherited_config.py
@@ -36,6 +36,12 @@ def test_contains():
     assert 'imread.jpg' in config
 
 
+def test_getitem():
+    config = InheritedConfig({'imread': 'a'})
+    assert config['imread'] == 'a'
+    assert config['imread.png'] == 'a'
+
+
 if __name__ == '__main__':
     from numpy import testing
     testing.run_module_suite()