Although the first specimen was collected over 30 years ago, scientists have only now confirmed that a tiny brown bat is indeed a unique species. Named Myotis diminutus for its incredibly small size, the new bat was discovered in the Chocó biodiversity hotspot, amid the moist forests of western Ecuador. "There are more than one hundred species of Myotis, twelve of which in South America and six in Ecuador. Myotis diminutus is the seventh Ecuadorian species, and the smallest of this group yet known in South America, weighing 3.5 grams," lead author of the paper describing the new species, Ricardo Moratelli, told mongabay.com.
The bat is likely gravely endangered according to Moratelli and may already be extinct, since the finding is based on a decades-old specimen. "Until new specimens of this insectivorous bat are caught, we will do not know whether the species is still living in nature. Only by inventory
discover if the species still survives. <…> If field works confirm the species only the moist forests of western Ecuador, it will probably be one of the most endangered South American species of bat."
The bat was found at the Río Palenque Scientific Center (RPSC), a private conservation reserve on the western slope of the Andes, where much of the forest in the region has been lost to agriculture.
"The moist forests of western Ecuador at one time covered a large part of the Pacific Coastal area, blanketing the coastal plain and extending up the relatively steep slopes of the western side of the Andes. These forests undoubtedly harbored an enormous wealth and diversity of species, but exist today as a disrupted series of tiny fragments under continuing threat and facing an uncertain future," explains Moratelli.
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http://news.mongabay.com/2010/1116-hance_tinybat.html