Ripe for the picking, straight from the vine, tomatoes frogs are the amphibious ilk to the vegetable that’s synonymous with Italian cuisine—or fruit, whatever set of semantics you’ve adopted.[vc_row][vc_column width=”2/3″][text_output] But, unlike the fruiting bodies of which they’re named after, tomato frogs occupy the world’s second largest island mass, Madagascar. And it’s on this lemur-laden, ocean-enveloped landmass where the tomato frogs evolved in isolation for the past 88 million years, amassing three distinct species. But just like Roma, Grape and Cherry tomatoes—the anurans come in a variety of phenotypic expressions.
Never Too Far From The Spigot
Tomato frogs inhabit the shallow, riparian-like conditions of Madagascar’s low-level topography, never found more than 200 meters above sea-level. Here, the corpulent frogs ambush their invertebrate prey, nestled within the forest floor’s leaf litter. Once the frogs reach sexual maturity at the ripe-young-age of 14 months, it’s not only easier to sex them at a glance, but it’s also evident which sex reigns supreme—it’s a woman’s world. Sexual dimorphism takes front-‘n’-center with females eclipsing their male suitors by a factor of five; adult females can often tip the scales at over 200 grams while the males weigh only a mere 40 grams on average. But “size isn’t everything”—it’s all in the calling-card. Males during the island’s heavy rainy season will emit a low-frequency, resonating croak that, in good hopes, will attract a suitable mate. Should the female be successfully swooned, she will lay around 13,000 eggs in a neighboring body of water, having been externally fertilized by the male’s sperm. And hatching just two days after fertilization, the young, measuring in mere millimeters, are left to “ripen” for themselves.
Tomayto, Tomahto—They’re All Alike
Of the three described species that occupy the genus Dyscophus, all are found within the same riparian habitats, all resembling the plump produce of which they’ve been named after. But, however, that’s not to say a “tomayto” is explicitly identical to a “tomahto”; there are subtle morphological differences. One glaring difference is the dorsal coloring of the lesser-known Antsouhy tomato frog (Dyscophus insularis) compared to that of the other two species, the Madagascar tomato (Dyscophus antongilii) frog and the false tomato frog (Dyscophus guineti). While the latter two species—specifically, the Madagascar tomato frog—exhibit vibrant hues of sun-kissed reds and over-ripened browns, the Antsouhy tomato frog is primarily absent of any vivid coloring. Enveloped with a seemingly permanent, muddied epidermis, these frogs are a far cry from the grocery store staple of which they’ve been named after. However, what may come across as Mother Nature’s day-off, the Antsouhy tomato frog, very likely, evolved that color scheme to more efficiently camouflage against its forest floor backdrop; the other two species seemed to have adopted the “brightly colored, stay away, I’m poisonous” mantra.
An Over Harvested Crop
Beauty may be in the eye of the beholder—but it’s also a marketable aesthetic. The frog’s exploitation in the pet trade has led to steep declines in all three species, specifically the Madagascar tomato frog—the most vibrant, “beautiful” of the three. To preserve these frogs for future generations, the exportation of these anurans must, at the very least, be better regulated. Ensuring that the hobbyist is purchasing only captive bred or farm reared animals is key to mainlining healthy population counts in the wild. Tomato frogs may be “ripe for the picking” in their endemic habitats—but that doesn’t mean they should be bothered.
By Matt Charnock[/text_output][/vc_column][vc_column width=”1/3″][text_output]The Madagascar tomato frog (Dyscophus antongilii) best exemplifies the genus’ red colouring. Photo © Frank Vassen[/text_output]
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