Monognathidae

fish family

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June 30, 2026

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The Monognathidae are a family of deep-sea fish, notable for being one of the three families that constitute "gulpers". Unlike other gulpers, which have disproportionately large mouths, the Monognathidae possess mouths of normal proportions. These fish inhabit depths of 2,700 meters (9,000 feet) or more. Gulpers, in general, are characterized by soft bodies, tapered forms, long tails, and highly expandable stomachs capable of accommodating large prey. They are typically black and some species have light-producing organs.1

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gulper
The members of one family, Monognathidae, have mouths of normal proportions, but the other gulpers (Eurypharyngidae and Saccopharyngidae) are noted for their enormous mouths. In the Eurypharyngidae, the mouth is longer than the body. In the Saccopharyngidae, it is somewhat smaller but still huge. Gulpers are soft-bodied fish with tapered…
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The members of one family, Monognathidae, have mouths of normal proportions, but the other gulpers (Eurypharyngidae and Saccopharyngidae) are noted for their enormous mouths. In the Eurypharyngidae, the mouth is longer than the body. In the Saccopharyngidae, it is somewhat smaller but still huge. Gulpers are soft-bodied fish with tapered…
Read More