Alternans?

[dragonfire1577]

This cannot be subspinipes, it doesn't make sense for an asian centipede to occur naturally in puerto rico. If you look on INaturalist.otg at centipedes on puerto rico you see both this species and more standard alternans so it also isn't alternans. To add to this not being subspinipes the animal in question does show a minimal ring furrow that is barely visible but it is made apparent that it is there when the pedes head moves forward while eating.

 

[dragonfire1577]

Here are photos of the furrow.

 

[Staehilomyces]

I still don't see a ring furrow. However, I will note that sometimes pedes will have a mark on their first tergite that resembles a ring furrow. I saw that on my old S. morsitans, which is a species that lacks a ring furrow.
Still subspinipes to me.

 

[CHLee]

This cannot be subspinipes, it doesn't make sense for an asian centipede to occur naturally in puerto rico. If you look on INaturalist.otg at centipedes on puerto rico you see both this species and more standard alternans so it also isn't alternans. To add to this not being subspinipes the animal in question does show a minimal ring furrow that is barely visible but it is made apparent that it is there when the pedes head moves forward while eating.

Subspinipes are found across the equator (Hawaii, Madagascar, south and Central America, south India, SE Asia etc) that’s not a ringfurrow it’s the forcipular pretergite

 

[dragonfire1577]

There is a small black band right behind the head on the first tergite before the membrane starts.

 

[micheldied]

This cannot be subspinipes, it doesn't make sense for an asian centipede to occur naturally in puerto rico. If you look on INaturalist.otg at centipedes on puerto rico you see both this species and more standard alternans so it also isn't alternans. To add to this not being subspinipes the animal in question does show a minimal ring furrow that is barely visible but it is made apparent that it is there when the pedes head moves forward while eating.

And brown rats aren't naturally found everywhere, but guess what? Singapore's waters are filled with Cichla. It's almost as if you can find species in an area they're not native to.

 

[dragonfire1577]

It just doesn't make sense for a species to be so widely distributed, these populations couldn't have easily interacted since at least 40 million years ago with the sheer distance between continents along the equator.

 

[CHLee]

There is a small black band right behind the head on the first tergite before the membrane starts.

Yes the forcipular pretergite

It just doesn't make sense for a species to be so widely distributed, these populations couldn't have easily interacted since at least 40 million years ago with the sheer distance between continents along the equator.

yes they can, examples
Rhysida longipes: originally from Africa, found in Florida, Southeast Asia, east Asia
Scolopendra morsitans: originally and old world species ranging from Africa, India down to australia, now found in some of the Caribbean islands.
With the nature of subspinipes all it takes is one Gravid female to be transported somewhere and they’ll proliferate

 

[Staehilomyces]

Subspinipes are also extremely common in Hawaii. As CH said, all it takes is the accidental transport of a gravid female.

 

[dragonfire1577]

And brown rats aren't naturally found everywhere, but guess what? Singapore's waters are filled with Cichla. It's almost as if you can find species in an area they're not native to.

Yes but looking at a layout of photos people have take of scolopendra in the Caribbean shows these guys on Guadeloupe, Martinique, Barbados, Port Elizabeth, Anguilla, and both Puerto rico and Vieques. Rats transport easily in ships, large scolopendrids don't have that luxury they can't breed aboard a ship and seed on an island as soon as the boat lands. It's hard to assume that human activity brought Scolopendra subspinipes to all these islands when most of them don't even permit import of non native inverts so the pet trade doesn't make sense and it would be hard for stow away pedes to move so evenly over the island chain as established before.

 

[dragonfire1577]

I just question it as similar specimens are found across many islands with no exceptions. It would be relatively hard to get a gravid female to all of those locations or establish enough healthy animals where two would meet and breed eventually populating the island enough for there to be photo reports of animals at every island.

 

[CHLee]

D

I just question it as similar specimens are found across many islands with no exceptions. It would be relatively hard to get a gravid female to all of those locations or establish enough healthy animals where two would meet and breed eventually populating the island enough for there to be photo reports of animals at every island.

During the 1500s, the Columbian Exchange, those ships would provide a suitable habitat for a large centipede that hitchhiked, they can last months without food, and subspinipes are ridiculously common where they’re native to. In HK you can even find them in the middle of the city as long as there are drains with water and no plant life in sight

 

[micheldied]

I just question it as similar specimens are found across many islands with no exceptions. It would be relatively hard to get a gravid female to all of those locations or establish enough healthy animals where two would meet and breed eventually populating the island enough for there to be photo reports of animals at every island.

So what you're saying is that even though they key out as subspinipes in every way, they definitely can't be subspinipes because you can't understand how a species can be so widely distributed.

 

[micheldied]

Yes but looking at a layout of photos people have take of scolopendra in the Caribbean shows these guys on Guadeloupe, Martinique, Barbados, Port Elizabeth, Anguilla, and both Puerto rico and Vieques. Rats transport easily in ships, large scolopendrids don't have that luxury they can't breed aboard a ship and seed on an island as soon as the boat lands. It's hard to assume that human activity brought Scolopendra subspinipes to all these islands when most of them don't even permit import of non native inverts so the pet trade doesn't make sense and it would be hard for stow away pedes to move so evenly over the island chain as established before.

Why can't they breed aboard a ship? You'll find Asian plants on all of those islands. It's not at all inconceivable that there were many stowaways in potted plants. Like CHLee said, go to Asia and you'll find them everywhere.

 

[dragonfire1577]

It just seems like a study on the anatomy and genetics of this specimen would be necessary to confirm or reject it's identity.

 

[Staehilomyces]

Obviously that would be required for a 100% certain I.D. However, from just the pics, I'm at least 90% sure it's a subspinipes.

 

[micheldied]

It just seems like a study on the anatomy and genetics of this specimen would be necessary to confirm or reject it's identity.

Or maybe they're subspinipes, which are found all around the world along the equator. Not sure why you're so adamant about this when you have no idea what a ringfurrow looks like.

 

[dragonfire1577]

Or maybe they're subspinipes, which are found all around the world along the equator. Not sure why you're so adamant about this when you have no idea what a ringfurrow looks like.

Sorry wasn't trying to make anyone angry. Also I'm aware the ring furrow is the suture on the first tergite I just was thinking I saw a very reduced/hidden one though it's not.

 

[Staehilomyces]

I don't think he's angry; he just doesn't understand why you seem so determined for it not to be a subspinipes.

 

[dragonfire1577]

I don't think he's angry; he just doesn't understand why you seem so determined for it not to be a subspinipes.

Yeah I understand how it could be, just seemed odd to me I found similar specimens on so many islands with variation between them and It kinda set the idea in my head this was a native species, though assuming man made establishment was hundreds of years ago it's a little less odd I need to read into subspinipes holotype though before I can judge. I actually just finished reading up on the Scolopendra gigantea/galapagoensis neotypes and distribution (having a solid understanding of those I generally feel white leg isn't gigantea btw).