(Photo by Franco Andreone)
Description: Very robust in appearance, Mantella expectata can grow to 30 mm (1.2 inches). As their common name suggests, they exhibit blue legs. Their legs contrast with their dorsum, which is yellow (sometimes with red fading posteriorly), and the sides of their body, which are black. Often the yellow dorsum is instead a darker yellow-green, and their legs a less attractive gray. This color variation seems to have less to do with individual variation, and more to do with the environmental conditions M. expectata are exposed to. In my experience, M. expectata most often display their brighter colors in captivity when temperatures are cool and the humidity level is low. At the start of the simulated wet season, an increase in temperature and humidity seem to encourage the captive M. expectata I have worked with to become dull in appearance, with gray legs and a dark muddy yellow dorsum. Some have also suggested that their colors are an indicator of their health or mood, with excited males or healthy frogs showing brighter colors, and shy or unhealthy frogs expressing those that are dull.
*A new species referred to in literature as M. aff. expectata or “desert mantella” from the far south and southwest has been identified. It appears similar to M. expectata but without blue legs
**The mantella frog commonly called the “blushing mantella” by hobbyists may be a color variant of M. expectata or perhaps, more likely, the new species referred to as M. aff. expectata
Red List Conservation Status: Endangered
Distribution and Habitat: M. expectata inhabits a small arid region of southwest Madagascar, in and around Isalo National Park. Here it lives near wet canyons and seasonal streams. Eggs have been found deposited on top of grassy tufts growing out of limestone walls above small pools of water. In at least a few locations, M. expectata occurs sympatrically with M. betsileo, where the two may hybridize.
Captive Care Notes: Wild-caught M. expectata are made available to North American hobbyists sporadically. Captive breeding is occasionally achieved, but is by no means common, and captive-bred frogs are only infrequently offered for sale. They require slightly different care than other mantella frogs, doing best in a fairly dry terrarium for much of the year. Access to water should be available so that the frogs remain hydrated, but the enclosure does not need to be misted frequently like it does for most other Mantella species. The substrate can remain fairly dry as a result, though moist areas under hide spots should always be available to avoid desiccation. Temperatures can range from 20°C to 28°C (68°F to 82°F), and can climb to 30°C (86°F) during a simulated rainy season. It’s best to time the driest conditions with the coolest temperatures, and the wettest with the warmest temperatures of the year to attempt to recreate similar conditions to what wild M. expectata experience. They eat food as large as 2 - 3 week old crickets, seeming to prefer these over Drosophila.
References
AmphibiaWeb: Information on amphibian biology and conservation. [web application]. 2007. Berkeley, California: AmphibiaWeb. Available: http://amphibiaweb.org/. (Accessed: Feb 21, 2007).
Andreone, Franco, V Mercurio, F Mattioli, and T J. Razafindrabe. 2005. Good News for Three Critically Endangered and Traded Frogs From Madagascar. FROGLOG 72.
Rabemananjara, F. C. E., A. Crottini, Y. Chiari, F. Andreone, F. Glaw, R. Duguet, P. Bora, O. Ravoahangimalala Ramilijaona & M. Vences. 2007. Molecular systematics of Malagasy poison frogs in the Mantella betsileo and M. laevigata species groups. Zootaxa 1501: 31-44.
Vences, M., F. Glaw & W. Böhme. 1999. A review of the genus Mantella (Anura, Ranidae, Mantellinae): taxonomy, distribution and conservation of Malagasy poison frogs. Alytes 17 (1-2): 3-72.
