Boa imperator "longicauda"

[Nightflight99]

Even though these are probably not a true subspecies of Boa imperator (following the recent reclassification into B. constrictor and B. imperator), the longtail boas from the Tumbes region of northern Peru are absolutely gorgeous and fascinating animals.

I was trigger happy with the camera today, so I figured I would share some recent shots of the longtail boas from my collection.

Top left: Female, Meltzer line. Probably my favorite "longicauda" in my collection.
Top right: Male, Meltzer line.

Center left: Male, produced by Vin Russo.
Center right: Female, produced by Eugene Bessette.

Bottom left: Male, also produced by Eugene Bessette.

[bigsnakegirl785]

Gorgeous animals!

And yeah, longicauda is Boa constrictor longicauda. Boa imperator is not a species, it's a subspecies Boa constrictor imperator.

[Nightflight99]

Originally Posted by bigsnakegirl785

Gorgeous animals!

And yeah, longicauda is Boa constrictor longicauda. Boa imperator is not a species, it's a subspecies Boa constrictor imperator.

Thank you!

Actually, not anymore. The original study by Hynková et al. (2009), which suggested that taxonomic reclassification, has since been corroborated by additional evidence (see Suárez‐Atilano et al. 2014, Reynolds et al. 2013, and Reynolds et al. 2014) and has been adopted by a number of authors (e.g., Sunyer 2014, Solis et al. 2014, McCranie 2015).

As a result, there are two species--Boa constrictor in South America east of the Andes, and Boa imperator, which includes the populations in Central American and South America west of the Andes, such as the longtail boas of northern Peru. I have an article in the works that explains the results of some of those studies--I'll reference that when its up.

[Tsubaki]

Gorgeous animals!, and nightflight i would love to read that.

[bigsnakegirl785]

Originally Posted by Nightflight99

Thank you!

Actually, not anymore. The original study by Hynková et al. (2009), which suggested that taxonomic reclassification, has since been corroborated by additional evidence (see Suárez‐Atilano et al. 2014, Reynolds et al. 2013, and Reynolds et al. 2014) and has been adopted by a number of authors (e.g., Sunyer 2014, Solis et al. 2014, McCranie 2015).

As a result, there are two species--Boa constrictor in South America east of the Andes, and Boa imperator, which includes the populations in Central American and South America west of the Andes, such as the longtail boas of northern Peru. I have an article in the works that explains the results of some of those studies--I'll reference that when its up.

It would be interesting to read those, because the last I heard about it was they would not be undergoing reclassification because the studies were using a clade system that was out of date.

I also only heard about Boa constrictor imperator becoming Boa imperator, not all the subspecies becoming either Boa constrictor or Boa imperator. It doesn't really make sense to me to put B.c.l or B.c.o under either of these new classifications.

[Nightflight99]

Originally Posted by bigsnakegirl785

It would be interesting to read those, because the last I heard about it was they would not be undergoing reclassification because the studies were using a clade system that was out of date.

No, that is incorrect. Hynková et al. (2009) used a standard phylogenetic framework to investigate those relationship. The troublesome aspects of that study was that it used a lot of captive specimens for tissue samples, and it utilized a single-gene approach, which is somewhat poor methodology for 2009. The other studies I quoted used solid methodologies, including multiple genes and more reliable samples, and were able to corroborate the split into B. constrictor and B. imperator.

Originally Posted by bigsnakegirl785

I also only heard about Boa constrictor imperator becoming Boa imperator, not all the subspecies becoming either Boa constrictor or Boa imperator. It doesn't really make sense to me to put B.c.l or B.c.o under either of these new classifications.

Yes, Boa c. imperator was elevated to species status, making it B. imperator. However, the subspecific epithet is a dying one--most practicing systematists have moved away from that concept, although that is a different topic for another day. The bottom line is that subspecies are typically either on a distinct evolutionary trajectory (in which case they are elevated to species status) or they are not (in which case they are synonymized). Either way, the subspecies status goes away.

Thus far, the evidence regarding the "longicauda" boas puts them square into the B. imperator group, without any indication that they are evolutionarily distinct from other B. imperator. The jury is still out on Boa c. occidentalis, as the sampling used by Hynková et al. (2009) was insufficient to make that call.

A lot of people have trouble wrapping their heads around changing taxonomy, mostly because they don't understand what it is meant to represent. People are always naturally focused on physical appearance, but taxonomy reflects evolutionary relationships, not degree of morphological similarity.

[bigsnakegirl785]

It certainly doesn't surprise me B.c.c and B.c.i becoming their own species, the only surprising bit for me is where they put B.c.o and B.c.l. I would have expected both of them to become their own species as well. Not so much from a physical perspective, because I couldn't look at the variety in imperator and say they don't belong in x or y group because of their appearance, but more because of the difference in the way they seem to metabolize food, and the significant difference in body structure from imperator or constrictor.

[Nightflight99]

I agree--there are lots of interesting aspects of the various localities and proposed subspecies of boas that make many of them distinct in some way. From a phylogenetics perspective, the island (and other isolated) forms are especially of interest, yet most of them were not included in any of the aforementioned studies, meaning that the jury is still out on Boa c. nebulosa, Boa c. orophias, Boa c. sigma, etc.

Thus far, the results have not really been surprising: many widespread species show a tremendous amount of (clinal) morphological variation, which is typically due to local conditions that the populations have adapted to. This also includes the physiological factors that you mentioned.

I'm working on a series of articles that aim to explain modern systematics and taxonomy to the average person, and one of the case studies in that series is Boa constrictor. Hopefully people will find that it helps them understand some of the recent taxonomic changes.

[Nightflight99]

This is another male from my B. i. "longicauda" group. He is a proven CB09 specimen, Denton/Dyer lineage.

[Lefitte]

I absolutely love longicaudas! A friend of mine breeds them and introduced me to them, though not in person unfortunately. I think that whenever I decide I want a larger snake (my biggest will be my male brb who is many times slimmer than a longi) that I really want a longi. I've often said that if I bred any snake, it would probably be brb or longi. Yours are gorgeous!

The taxonomy talk is interesting. I'm not well versed in it myself and I dont follow studies but I recently did an essay about the different subspecies of Epicrates in South America and came across a study that was calling for a change to make each one distict species instead of E.c. subspecies. (I.e. making Epicrates cenchria cenchria just Epicrates cenchria and, say, Epicrates cenchria assisi to Epicrates assisi). So I completely understand what you mean about the new trend being a move away from subspecies and into distinct species, I didn't realize that it was bigger than just Epicrates though. Interesting!

[AlexCrazy]

I'm not a Boa super lover.. but I like them.. and since you are talking about tipes of Boas.. these pictures were taken by a friend who lives on the north side of Paraguay.. very dry and hostile place.. And a photo of him with his girl Rosa (wild caught) hope to own one some day

[Nightflight99]

Originally Posted by Lefitte

The taxonomy talk is interesting. I'm not well versed in it myself and I dont follow studies but I recently did an essay about the different subspecies of Epicrates in South America and came across a study that was calling for a change to make each one distict species instead of E.c. subspecies. (I.e. making Epicrates cenchria cenchria just Epicrates cenchria and, say, Epicrates cenchria assisi to Epicrates assisi).

Yes, there is a strong trend among systematists to move away from the concept of subspecies (i.e., geographical variants). The rationale is that these "subspecies" are either evolving distinctly (in which case they are actually a separate species, rather than a subspecies) or they are not (in which case they are the same species). Either way, the subspecific epithet disappears. The genus Epicrates is a neat example of that, and I'm glad you came across that for your essay.

[Nightflight99]

A close-up shot of the head of the last specimen. The facial coloration of these boas is difficult to beat. They remind me a bit of the beautiful facial markings of Mexican cantils (Agkistrodon bilineatus) and Taylor's cantils (Agkistrodon taylori).