Gomphidae is an Odonata family that contains about 90 genera and 900 species. They are commonly referred to as clubtail dragonflies. The name refers to the clublike widening of the end of the abdomen (abdominal segments 7 through 9). However, this club is usually less pronounced in females and is entirely absent in some species.
Clubtails have widely separated eyes, a trait they share with the Petaluridae and with damselflies. Adults are usually from 40 to 70 mm in length.Most Gomphids breed in streams or rivers.
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