Reed frogs are some of Africa’s most diverse groups of frogs and as their name suggests, usually hang out on reeds overhanging ponds and ditches. A peculiarity of this group of frogs is that many of them don’t lay their eggs in water (like most frogs), but instead attach them to said reeds. Once the tadpoles are ready to hatch, they just drop into the water below! The reason for this strategy is most likely to avoid aquatic egg predators, a big risk for frogs (but check out this cool video of snakes feeding on such leave-bound eggs in the famous red-eyed tree frog in Central America: https://www.youtube.com/watch?v=dNHC4OciQJw).

The two biggest groups (or ‘genera’) of reed frogs are Hyperolius and Afrixalus. The latter are sometimes referred to as the “spiny reed frogs” due to their rough, sandpaper-like skin and both are fairly wide-spread across the African subcontinent. Besides their spiny skin, Afrixalus has one more peculiarity up its sleeve… as day breaks and they search for places to rest (most frogs are nocturnal), they dramatically change their colour with some going completely white! Although most (if not all) frogs are able to change color to some extent (usually limited to different shades or intensities of the same colour), reed frogs like this Afrixalus uluguruensis are literally like night and day!

Although this oddity is fairly well known, and other species of frogs do it too, surprisingly little is known about the exact function of this colour change. Dramatically paler day time colourations are often seen in those species that also rest in fairly exposed places and so it might serve as some sort of UV protection or to keep cool and prevent dehydration during the sunniest parts of the day, but these hypotheses are yet to be formally tested.

-Christoph Liedtke

     One of the most exciting parts of working in biologically diverse and understudied areas such at the Eastern Arc Mountains of Tanzania is finding new species! However, it can often be a very confusing process to decide if something is truly new. In reality, we often end up listing these as "cf. somethingsomething" which comes from the Latin word "conferre" meaning “compare to” or “confer.” For instance, this little guy is currently listed as Hyperolius cf. pusillus. While these frogs look something like H. pusillus, their call is different and they are found in the wrong habitat and in the wrong region of the country - thus we think they aren't really H. pusillus at all! Now begins the long hard work of describing a new species.
     The first step of describing a new species is figuring out what it ISN'T. Figuring out what it isn't requires us to compare this frog to other similar frogs to determine if we can rule them out. In modern herpetology, we employ a wide variety of techniques to characterize a species and sample a number of individuals in order to understand within-species variation in relation to between-species variation. We take morphological measurements of every aspect of these little frogs, we document coloration and variation (some species are hyper-variable even within a single clutch of eggs), we record calls, we sample DNA, and we document habitat type and distribution. Finally, we take all of this information into account and compare to all other similar species - noting ways in which they are similar and ways in which the differ.

Other species have incredible variation within single populations and throughout their ranges, such as Hyperolius substriatus found throughout mid-elevation forests in East Africa (right). Though challenging when doing biodiversity surveys, new species are incredibly exciting and incredibly valuable for conservation planning. When formulating a plan for conservation, if scientists can clarify that three species with small ranges exist instead of one broadly distributed species, for instance, then conservation biologists can create more targeted action plans for these vulnerable species.

-Lucinda Lawson