Xerobdellidae are a small family of jawed leeches in the order Arhynchobdellida. Xerobdellidae have three jaws and five pairs of eyes, the fourth and fifth being separated by one or two eyeless segments. The genera placed herein occur in Chile (Mesobdella), Europe (Xerobdella) and Diestecostoma is found in Central and northern South America. This peculiar distribution strongly suggests they are a relict Pangaean group, which had already been present by the start of the Jurassic 250 million years ago.

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