A new Papiliolebias killifish
From 1989 to 2009, Papiliolebias was a monotypic (single species) genus. Every couple of years starting 2009, a new species was described. Papiliolebias habluetzeli is newest and is only the fifth valid species of the relatively new genus. It is described in Aqua, the International Journal of Ichthyology.
P.habluetzeli most closely resembles P.francescae, which was only described back in 2014 as we reported. P.francescae also was discovered in Bolivia. As described by the paper, "it differs from Papiliolebias francescae by male flank and anal fin color pattern and different number of branchiostegal rays and pelvic fin rays."
Learn about annual killifishes' amazing life cycles (excerpt from a 2015 article):
[Annual killifish] spend their entire lives living in temporary bodies of water - waters that fill during the rainy season but completely dry out during the dry seasons. This means the fish have a complete life cycle of just one year (hence the name, annual fish, like annual flowers).
For these species to propagate successive generations in such extreme conditions, they've developed equally extreme abilities that include rapid growth rates, very early sexual maturity, and super high reproductivity. Each year, hundreds of eggs are buried into shallow substrate where they spend months during the dry season waiting for the rain to return to flood their patch of water. When the waters return, the eggs hatch and the fry grow extremely quickly, reaching sexual maturity in a matter of weeks. The whole reproductive cycle starts anew before the dry season comes again. Once the rapidly matured fish - fish that hatched only earlier in the year - reproduce, they all die when the dry season reclaims their water.
Wild annual killifish don't live more than a year, but domestically bred annuals can live for two or more years. The unique life cycles of these fish present an unique challenge (and reward) for captive husbandry and breeding.
For a more detailed description of African annual killifish, read this excellent TFH article.