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Meet today's #FrogOfTheDay #11 Mantella madagascariensis (Grandidier, 1872), the first species of 'poison arrow' frog described from Madagascar! A feat of spectacular #ConvergentEvolution among the #MadagascarFrogs 
Vences&Glaw, CalPhotos
Vences&Glaw, CalPhotos
It's hard to even know where to start to talk about this incredible frog. It's a small species at 20–25 mm adult size, native to the rainforests of central eastern Madagascar. It is strikingly coloured, a form of #aposematism, because it is also poisonous! #MadagascarFrogs
The resemblance between Malagasy dart frogs in the genus Mantella and their American counterparts is so striking that Alfred Grandidier originally described this species in the genus Dendrobates (American poison arrow frogs) #MadagascarFrogs
We know now that #Mantella are, however, not at all closely related to #Dendrobates and other American poison frogs. Instead, they represent one of the most spectacular cases of #ConvergentEvolution of which I am aware. #MadagascarFrogs
Almost every aspect of Mantella frogs has converged on their American counterparts. They hop instead of leaping. They sequester toxin from their prey. They are brightly coloured. They exhibit mimicry among species. The list goes on #MadagascarFrogs
Amazingly, the #ConvergentEvolution around poison sequestration doesn't seem to stop at the frogs—they get their toxins from ants & other arthropods, which have also convergently arrived at the same chemical defence as American arthropods! https://www.pnas.org/content/102/33/11617.short #MadagascarFrogs
This frog (and the one we will meet tomorrow) would only remain in Dendrobates for a decade, before George Albert Boulenger would recognise the degree of differentiation between these groups, and move the Malagasy species to the genus Mantella #MadagascarFrogs Wikimedia
Wikimedia
Today there are 16 recognised Mantella species, just 6.9% of the whole family Mantellidae, but for some reason people often assume that these frogs represent the whole family; to put it plainly, they very much do not. #MadagascarFrogs