I had a tie for this. The runner up is the Surinam Toad, who I might write about someday, but the winner is the Caucasian rock lizard, Darevskia (or Lacerta, the nomenclature is confusing) rostombekovi.
Now these gals are parthenogenetic, which isn’t particularly weird for a herp. There’s several species that do this. Some, like whiptails in the genus Cnemidophorus, are neat in that they actually practice female-female courting behavior and require stimulation to reproduce. Another species, the mourning gecko (Lepidodactylus lugubris), is fascinating because sometimes physical males do crop up that produce sperm… that’s completely useless. They can’t impregnate a female. But the Caucasian rock lizard is something else entirely.
Also called Rostombekov’s Lizard, this creature is unique because it’s monoclonal, meaning there’s only one genetic lineage. There never was a male. Literally every single member of this species is genetically identical to her sisters.
There are several parthenogenetic species in the genus Darevskia, but the rest of them have multiple lineages and so there’s some genetic diversity. That is absolutely not true of this particular lizard. How did this happen? What kind of speciation event led to a single clonal line for an entire species? We do know that the other Caucasian rock lizards that are strictly parthenogenetic have wider ranges than their bisexual ancestors, but this species is shamefully under-studied; we know very little about them, other than that they’re threatened by land development and they’re all genetically identical. That is unheard of in vertebrates.
So here’s to you, weird identical lizard ladies. Science can’t tell me what the hell happened to you, but you do you.
Literally. Because you’re all clones of each other.
