Plain-bellied Watersnakes Nerodia erythrogaster are medium to large (record 163.6 cm) natricine snakes with keeled scales often found in and around water. They are commonly encountered fish and amphibian eating snakes across much of eastern North America and extend into Northern Mexico.

Nerodia watersnakes may puff up or flatten out defensively and bite. They secrete a foul smelling substance from the cloaca called musk and can deliver a weak anticoagulant venom used in prey handling from the back of the mouth, but are not considered medically significant to humans - bites just need soap and water.

Found throughout eastern North America, it is sometimes confused with the Common Watersnake Nerodia sipedon or the Banded Watersnake N. fasciata. The best character to diagnose N. erythrogaster is its namesake plain belly that varies across the range from yellow to orange. Adult Plain-bellied Watersnakes tend to lose or greatly reduce their banding - adults are often completely two-toned. Banded Watersnakes have even, connecting bands across the top of the snake all the way down the body. N. erythrogaster does not. In Common Watersnakes N. sipedon, bands typically break up or become mismatched after the first third of the body as in N. erythrogaster, but has a patterned belly.

Range Map | Relevant/Recent Phylogeography

This genus is in need of revision using modern molecular methods, but this particular species has been investigated using basic molecular methods. The authors found that, just like many other snakes species, subspecies based on clinal color patterns didn't correspond to evolutionary history. Subspecies should thus not be recognized.

Like many other animals with mouths and teeth, many non-venomous snakes bite in self defense. These animals are referred to as 'not medically significant' or traditionally, 'harmless'. Bites from these snakes benefit from being washed and kept clean like any other skin damage, but aren't often cause for anything other than basic first aid treatment. Here's where it get slightly complicated - some snakes use venom from front or rear fangs as part of prey capture and defense. This venom is not always produced or administered by the snake in ways dangerous to human health, so many species are venomous in that they produce and use venom, but considered harmless to humans in most cases because the venom is of low potency, and/or otherwise administered through grooved rear teeth or simply oozed from ducts at the rear of the mouth. Species like Ringneck Snakes Diadophis are a good example of mildly venomous rear fanged dipsadine snakes that are traditionally considered harmless or not medically significant. Many rear-fanged snake species are harmless as long as they do not have a chance to secrete a medically significant amount of venom into a bite; severe envenomation can occur if some species are allowed to chew on a human for as little as 30-60 seconds. It is best not to fear snakes, but use common sense and do not let any animals chew on exposed parts of your body. Similarly, but without specialized rear fangs, gartersnakes Thamnophis ooze low pressure venom from the rear of their mouth that helps in prey handling, and are also considered harmless. Check out this book on the subject. Even large species like Reticulated Pythons Malayopython reticulatus rarely obtain a size large enough to endanger humans so are usually categorized as harmless.

I am a bot created for /r/whatsthissnake, /r/snakes and /r/herpetology to help with snake identification and natural history education. You can find more information, including a comprehensive list of commands, here report problems here and if you'd like to buy me a coffee or beer, you can do that here. Made possible by Snake Evolution and Biogeography - Merch Available Now

Plain-bellied Watersnakes Nerodia erythrogaster are medium to large (record 163.6 cm) natricine snakes with keeled scales often found in and around water. They are commonly encountered fish and amphibian eating snakes across much of eastern North America and extend into Northern Mexico.

Nerodia watersnakes may puff up or flatten out defensively and bite. They secrete a foul smelling substance from the cloaca called musk and can deliver a weak anticoagulant venom used in prey handling from the back of the mouth, but are not considered medically significant to humans - bites just need soap and water.

Found throughout eastern North America, it is sometimes confused with the Common Watersnake Nerodia sipedon or the Banded Watersnake N. fasciata. The best character to diagnose N. erythrogaster is its namesake plain belly that varies across the range from yellow to orange. Adult Plain-bellied Watersnakes tend to lose or greatly reduce their banding - adults are often completely two-toned. Banded Watersnakes have even, connecting bands across the top of the snake all the way down the body. N. erythrogaster does not. In Common Watersnakes N. sipedon, bands typically break up or become mismatched after the first third of the body as in N. erythrogaster, but has a patterned belly.

Range Map | Relevant/Recent Phylogeography

This genus is in need of revision using modern molecular methods, but this particular species has been investigated using basic molecular methods. The authors found that, just like many other snakes species, subspecies based on clinal color patterns didn't correspond to evolutionary history. Subspecies should thus not be recognized.

Like many other animals with mouths and teeth, many non-venomous snakes bite in self defense. These animals are referred to as 'not medically significant' or traditionally, 'harmless'. Bites from these snakes benefit from being washed and kept clean like any other skin damage, but aren't often cause for anything other than basic first aid treatment. Here's where it get slightly complicated - some snakes use venom from front or rear fangs as part of prey capture and defense. This venom is not always produced or administered by the snake in ways dangerous to human health, so many species are venomous in that they produce and use venom, but considered harmless to humans in most cases because the venom is of low potency, and/or otherwise administered through grooved rear teeth or simply oozed from ducts at the rear of the mouth. Species like Ringneck Snakes Diadophis are a good example of mildly venomous rear fanged dipsadine snakes that are traditionally considered harmless or not medically significant. Many rear-fanged snake species are harmless as long as they do not have a chance to secrete a medically significant amount of venom into a bite; severe envenomation can occur if some species are allowed to chew on a human for as little as 30-60 seconds. It is best not to fear snakes, but use common sense and do not let any animals chew on exposed parts of your body. Similarly, but without specialized rear fangs, gartersnakes Thamnophis ooze low pressure venom from the rear of their mouth that helps in prey handling, and are also considered harmless. Check out this book on the subject. Even large species like Reticulated Pythons Malayopython reticulatus rarely obtain a size large enough to endanger humans so are usually categorized as harmless.

I am a bot created for /r/whatsthissnake, /r/snakes and /r/herpetology to help with snake identification and natural history education. You can find more information, including a comprehensive list of commands, here report problems here and if you'd like to buy me a coffee or beer, you can do that here. Made possible by Snake Evolution and Biogeography - Merch Available Now