Xantusia vigilis vigilis

[DallasJolly123]

Nothing special by any means, but a herp none the less. My name is Dallas Jolly and I'm a newbie to the forum, I've made one or two posts in the past but I'd like to make it regular thing this year. Anyway... three of several from today.

Mojave Desert Habitat


Desert Night Lizards (Xantusia vigilis vigilis) in habitat




-Dallas

[Zach_Lim]

Beautiful shots of a wonderful lizard! Great post

[DallasJolly123]

Beautiful shots of a wonderful lizard! Great post

Thank you Zach

[klawnskale]

Xantusia are wonderful little lizards. They are a very interesting Genus and have certain physiological traits unique to them. They are one of the few lizard species which are actually viviparous (or as close to the mammalian definition as you can get). Their body actually develops an organ analogous to the mammalian placenta during gestation and truly "give birth" to live young.

[DallasJolly123]

Xantusia are wonderful little lizards. They are a very interesting Genus and have certain physiological traits unique to them. They are one of the few lizard species which are actually viviparous (or as close to the mammalian definition as you can get). Their body actually develops an organ analogous to the mammalian placenta during gestation and truly "give birth" to live young.

Thanks for the input.
They are very unique little animals. I can remember reading an article on Xantusia vigilis that pointed out their low reproductive potential (possibly the lowest among lizards) based on slow growth rate and late maturity. I also recall reading that individuals can live 9 years and probably even longer. Anyway, I found that to be interesting.

[hellihooks]

They don't actually give birth to live young (implying multiples) they give birth to only ONE live offspring at a time (which is due to the lg size attained through their nearly 'placental' development) and then live in familial groups for several years... also very unique amongst lizards.

[Bryan Hamilton]

I love me some Xantusia. Placental birth and true viviparity is pretty widespread in reptiles.

Really interesting perspectives and contributions from klawnsnake and hellihooks. Thanks for sharing.

[hellihooks]

I love me some Xantusia. Placental birth and true viviparity is pretty widespread in reptiles.

Really interesting perspectives and contributions from klawnsnake and hellihooks. Thanks for sharing.

I've had visitors from all over the world take my guided 'Mojave tour'... and invariable... the first thing they want to see is a night lizard...

[Kyle from Carolina]

Great post. Night lizards would be a top target of mine if I were to ever visit somewhere within their range.

Xantusia are wonderful little lizards. They are a very interesting Genus and have certain physiological traits unique to them. They are one of the few lizard species which are actually viviparous (or as close to the mammalian definition as you can get). Their body actually develops an organ analogous to the mammalian placenta during gestation and truly "give birth" to live young.

^ That's awesome, I never knew that.

I love me some Xantusia. Placental birth and true viviparity is pretty widespread in reptiles.

Really interesting perspectives and contributions from klawnsnake and hellihooks. Thanks for sharing.

Bryan, do you have other examples of squamates that have placental birth? I had thought it was pretty uncommon.

[Fieldnotes]

Pretty cool, reminds me of finding them at Stoddard Ridge decades ago. Also found a juvenile banded gecko, Giant hairy Scorpion, and some chucks that day.

[DallasJolly123]

Thanks again everyone, I had no clue how popular Night Lizards were among herpers! Personally they remind me of a micro sized Varanid... to a certain degree.
Have any of you seen a new born Xantusia? I would love to see how unbelievably small they are.

[klawnskale]

Thanks again everyone, I had no clue how popular Night Lizards were among herpers! Personally they remind me of a micro sized Varanid... to a certain degree.
Have any of you seen a new born Xantusia? I would love to see how unbelievably small they are.

Actually yes. I had a friend who years ago collected some and kept a small group in a nice terrarium set up. One of the females was pregnant and gave birth to this ginormous neonate that was almost as large as her. I don't think you can collect them any longer in LA County. I think CDF&W changed the regs. But they do make cool captives to observe since they are social.

[hellihooks]

They're not hard to find, if you know how, when and where... there's a spot 5 min from my house, where i can flip several dozen an hour... even in 6 inches of snow. no time to look for my 'snowy night' pics right now (gotta go to work) but hopefully this'll do, for now...

[DallasJolly123]

Thanks again everyone, I had no clue how popular Night Lizards were among herpers! Personally they remind me of a micro sized Varanid... to a certain degree.
Have any of you seen a new born Xantusia? I would love to see how unbelievably small they are.

Actually yes. I had a friend who years ago collected some and kept a small group in a nice terrarium set up. One of the females was pregnant and gave birth to this ginormous neonate that was almost as large as her. I don't think you can collect them any longer in LA County. I think CDF&W changed the regs. But they do make cool captives to observe since they are social.

Awesome! I've heard they exhibit diurnal activities in captivity too, that does sound cool to observe.

[DallasJolly123]

They're not hard to find, if you know how, when and where... there's a spot 5 min from my house, where i can flip several dozen an hour... even in 6 inches of snow. no time to look for my 'snowy night' pics right now (gotta go to work) but hopefully this'll do, for now...

I've just never seen a newborn personally yet, thanks for posting that. I gotta see one of those "snowy night" shots. I too can find them nearby and even in my yard. Hell I probably saw a dozen while out earlier today along with a pair of Anniella. My first lifer of 2016!

[klawnskale]

Littlerock is an interesting transitional area ecologically; a mixture of coastal sage scrub and high desert. There are clumped areas of fairly dense Joshua Tree Forest which Xantusia love. Also, there have been reports by some herpers of individual specimens of rattlesnakes which appear to show traits of both Southern Pacific and Mojaves; possibly intergrades. Some of the Forum participants may have photos showing these so called intergrades. I think DNA analysis would be the surefire way to determine whether these animals were truly intergrades.

[DallasJolly123]

Im new to the area but I enjoy it.
I've found Mojaves and Southern Pacifics on the same roads in my area last year. I'm always hoping to see an unusual looking rattler but no such luck. I have seen a couple Gopher Snakes that looked like Great Basin/San Diego intergrades though.

[Bryan Hamilton]

Bryan, do you have other examples of squamates that have placental birth? I had thought it was pretty uncommon.

I just looked at a handful of papers and placental birth in squamates is apparently uncommon....

Skinks have most highly developed placentas. Liolaemis lizards, boas, gartersnakes, and pit vipers apparently have more primitive placentation. I didn't find much about Xantusia, but I didn't spend much time searching.

I found this quote interesting: "The vast majority of viviparous squamates are characterized by simple (type I) placentation (lecithotrophic) in which shell-less eggs are retained in utero, and embryos are sustained largely or wholly by a large nutrient-rich yolk, with little placental nutrient exchange."

I would say that the closer we look at placentation in squamates, the more complex and mammalian like we find it.

Sites, J. W., Jr., T. Reeder, and J. J.Wiens 2011. Phylogenetic Insights on Evolutionary Novelties in Lizards and Snakes: Sex, Birth, Bodies, Niches, and Venom. Annual Review of Ecology and Systematics 42.

[regalringneck]

for those interested in things xantuid, & especially if you want to keep them ... dont overlook the central american giants (pinky eaters i understand) ... & our az beazyii ... i know a mellowfellow who maintained beazii & vigilis in the same vivaria, had neonates produced , but no hybridization ??? same thing w/ henshawii & vigilis ... good clean sps. the one i'd like to take a closer look at is riversiana; channel isla ... but i think theyre paws off : {

[hellihooks]

same thing w/ henshawii & vigilis ... good clean sps. the one i'd like to take a closer look at is riversiana; channel isla ... but i think theyre paws off : {

henshawii is hands off, as well.

[hellihooks]

Im new to the area but I enjoy it.
I've found Mojaves and Southern Pacifics on the same roads in my area last year. I'm always hoping to see an unusual looking rattler but no such luck. I have seen a couple Gopher Snakes that looked like Great Basin/San Diego intergrades though.

Yes... almost certainly SD/GB gopher X's there... I live in the same transitional zone further east, and see many intergrades. Along with night lizards I have side blotch, western fence, yellowback spinys, SAL and coast horned lizards in my backyard. and intergrade night snakes.. along with the gophers and red coaches that pass through.

I seen some of the suspected 'hybrid' So pac/scute from your area... light green helleri... had them tested at LLU by Dr Hayes, who has a good collection of hybrids... no helleri/scute hybrid has ever been proven. your area is rather under-represented in regard to data collection, so i hope you'll consider entering your finds at HERP. also... we could use someone from your area, in our hi desert snake relocation/response team at High Desert Wildlife group on FB. gotta go to work... cyaaaaaaaa

BTW... the facebook wildlife pg is run by Nafha members, including our chapter vice Pres... and you may want to chek out our annual Tejon Ranch surveys coming up... always awesome...

[DallasJolly123]

Im new to the area but I enjoy it.
I've found Mojaves and Southern Pacifics on the same roads in my area last year. I'm always hoping to see an unusual looking rattler but no such luck. I have seen a couple Gopher Snakes that looked like Great Basin/San Diego intergrades though.

Yes... almost certainly SD/GB gopher X's there... I live in the same transitional zone further east, and see many intergrades. Along with night lizards I have side blotch, western fence, yellowback spinys, SAL and coast horned lizards in my backyard. and intergrade night snakes.. along with the gophers and red coaches that pass through.

I seen some of the suspected 'hybrid' So pac/scute from your area... light green helleri... had them tested at LLU by Dr Hayes, who has a good collection of hybrids... no helleri/scute hybrid has ever been proven. your area is rather under-represented in regard to data collection, so i hope you'll consider entering your finds at HERP. also... we could use someone from your area, in our hi desert snake relocation/response team at High Desert Wildlife group on FB. gotta go to work... cyaaaaaaaa

BTW... the facebook wildlife pg is run by Nafha members, including our chapter vice Pres... and you may want to chek out our annual Tejon Ranch surveys coming up... always awesome...

I recently made an account on naherp so I will certainly be entering my finds. Also, in regards to the hi desert relocation/response team I am almost always free to do so if the opportunity does arise. However I don't have an FB so I'll have to make one sometime.

[hellihooks]

https://www.facebook.com/groups/highdes ... =bookmarks

edit (12 hrs later) 'night' lizards is a bit of a misnomer... they are known to be active above ground, at dawn and dusk...