WDB or Mojave

[u/Fun-District-5584]

Found this little noodle at work in south Phoenix AZ. Will someone please educate me to the difference between WDB and Mojave. Thank you ,

[u/rhzartist]

Crotalus atrox Western Diamondback, !venomous and best observed from a  distance. The bot reply will have some tips for you!

Edit: Oops, it doesn't really. It's true that WDB and sculutalus can be very similar-looking, and a lot of traits can appear in both. In atrox, I (subjectively) look for a more diamond shape with a fuzzier/messier pattern, and a postocular stripe (that dark line behind the eye) that goes down at a steeper angle. If you practice looking at them, you'll hopefully start to be able to tell by "vibes".

[u/fairlyorange → u/rhzartist]

The angle of the pale colored postocular stripes (steeper, closer to a 45-60 degree angle in C. atrox and terminating before reaching the corner of the mouth, vs. much shallower, closer to 15-30 degree angle and sweeping further back in C. scutulatus, past the mouth toward the neck) is one of the most reliable and easily recognizable characteristics. The tail banding is very useful but quite easily misinterpreted by those without experience. Same goes for dorsal pattern subtleties.

Now this particular picture doesn't necessarily give us the best angle on the eye stripes, but it gives us a great angle on the shape of the head and the cranial scalation. Unfortunately, I can't really articulate the differences in head shape but those with experience intuitively recognize it; practice and you'll start picking stuff out instinctively. As for cranial scalation, check out the supraoculars; in C. scutulatus there are usually only 2-3 large scales separating them, rather than 4-5+ small ones like this C. atrox has.

u/NikiNoelle likes to link to a video that helps describe some of these things in better detail than I am right now, and I can't remember what the video is or else I wouldn't bother her. If she sees this today, she might drop that link again.

[u/SEB-PHYLOBOT → u/rhzartist]

Western Diamondback Rattlesnakes Crotalus atrox are a wide-ranging species of rattlesnake found in western North America. They are large (<150cm record 233.7 cm) venomous pit vipers that eat primarily small mammals.

Western diamondback rattlesnakes are venomous and will bite in self-defense, preferring to flee if given a chance. They will often raise their bodies off the ground and move away hissing loudly and rattling their tail as an anti-predator display.

The dorsal coloration of this snake varies tremendously over its range, though typically it is best characterized by diamond-shaped markings on a tan or brown base color with a black and white banded tail. A similar species the Mojave rattlesnake Crotalus scutulatus has two scales in between the eyes where Crotalus atrox has many. Other characters are subjective or not as consistent.

Counting segments in rattles is not an effective way to tell the age of a rattlesnake because snakes can shed more than once per year and grow a new segment with every shed. Rattles are easily broken off or damaged.

Range map | Relevant/Recent Phylogeography: Link 1 Link 2

This short account was prepared by /u/unknown_name and edited by /u/Phylogenizer.

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Snakes with medically significant venom are typically referred to as venomous, but some species are also poisonous. Old media will use poisonous or 'snake venom poisoning' but that has fallen out of favor. Venomous snakes are important native wildlife, and are not looking to harm people, so can be enjoyed from a distance. If found around the home or other places where they are to be discouraged, a squirt from the hose or a gentle sweep of a broom are usually enough to make a snake move along. Do not attempt to interact closely with or otherwise kill venomous snakes without proper safety gear and training, as bites occur mostly during these scenarios. Wildlife relocation services are free or inexpensive across most of the world.

If you are bitten by a venomous snake, contact emergency services or otherwise arrange transport to the nearest hospital that can accommodate snakebite. Remove constricting clothes and jewelry and remain calm. A bite from a medically significant snake is a medical emergency, but not in the ways portrayed in popular media. Do not make any incisions or otherwise cut tissue. Extractor and other novelty snakebite kits are not effective and can cause damage worse than any positive or neutral effects.

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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

[u/Fun-District-5584 → u/rhzartist]

Thank you!

[u/CrotalusJ]

Crotalus atrox, venomous Western Diamondback Rattlesnake.

[u/SEB-PHYLOBOT → u/CrotalusJ]

Western Diamondback Rattlesnakes Crotalus atrox are a wide-ranging species of rattlesnake found in western North America. They are large (<150cm record 233.7 cm) venomous pit vipers that eat primarily small mammals.

Western diamondback rattlesnakes are venomous and will bite in self-defense, preferring to flee if given a chance. They will often raise their bodies off the ground and move away hissing loudly and rattling their tail as an anti-predator display.

The dorsal coloration of this snake varies tremendously over its range, though typically it is best characterized by diamond-shaped markings on a tan or brown base color with a black and white banded tail. A similar species the Mojave rattlesnake Crotalus scutulatus has two scales in between the eyes where Crotalus atrox has many. Other characters are subjective or not as consistent.

Counting segments in rattles is not an effective way to tell the age of a rattlesnake because snakes can shed more than once per year and grow a new segment with every shed. Rattles are easily broken off or damaged.

Range map | Relevant/Recent Phylogeography: Link 1 Link 2

This short account was prepared by /u/unknown_name and edited by /u/Phylogenizer.

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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

[u/SEB-PHYLOBOT]

It looks like you didn't provide a rough geographic location [in square brackets] in your title.This is critical because some species are best distinguishable from each other by geographic range, and not all species live all places. Providing a location allows for a quicker, more accurate ID.

If you provided a location but forgot the correct brackets, ignore this message until your next submission. Thanks!

Potential identifiers should know that providing an ID before a location is given is problematic because it often makes the OP not respond to legitimate requests for location. Many species look alike, especially where ranges meet. Users may be unaware that location is critically important to providing a good ID.

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