Boa imperator "longicauda"

[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heard about it was they would not be undergoing reclassification because the studies were using a clade system that was out of date.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heard about it was they would not be undergoing reclassification because the studies were using a clade system that was out of date.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.